Characterizing the temporal patterns of avian influenza virus introduction into Japan by migratory birds

PubMed Central

ONUMA, Manabu; KAKOGAWA, Masayoshi; YANAGISAWA, Masae; HAGA, Atsushi; OKANO, Tomomi; NEAGARI, Yasuko; OKANO, Tsukasa; GOKA, Koichi; ASAKAWA, Mitsuhiko

2017-01-01

The objectives of the present study were to observe the temporal pattern of avian influenza virus (AIV) introduction into Japan and to determine which migratory birds play an important role in introducing AIV. In total, 19,407 fecal samples from migratory birds were collected at 52 sites between October 2008 and May 2015. Total nucleic acids extracted from the fecal samples were subjected to reverse transcription loop–mediated isothermal amplification to detect viral RNA. Species identification of host migratory birds was conducted by DNA barcoding for positive fecal samples. The total number of positive samples was 352 (prevalence, 1.8%). The highest prevalence was observed in autumn migration, and a decrease in prevalence was observed. During autumn migration, central to southern Japan showed a prevalence higher than the overall prevalence. Thus, the main AIV entry routes may involve crossing the Sea of Japan and entry through the Korean Peninsula. Species identification was successful in 221 of the 352 positive samples. Two major species sequences were identified: the Mallard/Eastern Spot-billed duck group (115 samples; 52.0%) and the Northern pintail (61 samples; 27.6%). To gain a better understanding of the ecology of AIV in Japan and the introduction pattern of highly pathogenic avian influenza viruses, information regarding AIV prevalence by species, the prevalence of hatch-year migratory birds, migration patterns and viral subtypes in fecal samples using egg inoculation and molecular-based methods in combination is required. PMID:28484128

Migration along orthodromic sun compass routes by arctic birds.

PubMed

Alerstam, T; Gudmundsson, G A; Green, M; Hedenstrom, A

2001-01-12

Flight directions of birds migrating at high geographic and magnetic latitudes can be used to test bird orientation by celestial or geomagnetic compass systems under polar conditions. Migration patterns of arctic shorebirds, revealed by tracking radar studies during an icebreaker expedition along the Northwest Passage in 1999, support predicted sun compass trajectories but cannot be reconciled with orientation along either geographic or magnetic loxodromes (rhumb lines). Sun compass routes are similar to orthodromes (great circle routes) at high latitudes, showing changing geographic courses as the birds traverse longitudes and their internal clock gets out of phase with local time. These routes bring the shorebirds from high arctic Canada to the east coast of North America, from which they make transoceanic flights to South America. The observations are also consistent with a migration link between Siberia and the Beaufort Sea region by way of sun compass routes across the Arctic Ocean.

Development of Matched (migratory Analytical Time Change Easy Detection) Method for Satellite-Tracked Migratory Birds

NASA Astrophysics Data System (ADS)

Doko, Tomoko; Chen, Wenbo; Higuchi, Hiroyoshi

2016-06-01

Satellite tracking technology has been used to reveal the migration patterns and flyways of migratory birds. In general, bird migration can be classified according to migration status. These statuses include the wintering period, spring migration, breeding period, and autumn migration. To determine the migration status, periods of these statuses should be individually determined, but there is no objective method to define 'a threshold date' for when an individual bird changes its status. The research objective is to develop an effective and objective method to determine threshold dates of migration status based on satellite-tracked data. The developed method was named the "MATCHED (Migratory Analytical Time Change Easy Detection) method". In order to demonstrate the method, data acquired from satellite-tracked Tundra Swans were used. MATCHED method is composed by six steps: 1) dataset preparation, 2) time frame creation, 3) automatic identification, 4) visualization of change points, 5) interpretation, and 6) manual correction. Accuracy was tested. In general, MATCHED method was proved powerful to identify the change points between migration status as well as stopovers. Nevertheless, identifying "exact" threshold dates is still challenging. Limitation and application of this method was discussed.

Use of NEXRAD to study shorebird migration in the Prairie Pothole region: A feasibility study

USGS Publications Warehouse

Melcher, Cynthia P.; Skagen, Susan K.; Randall, Lori

2006-01-01

An essential component of shorebird conservation is identifying, protecting, and managing high-priority stopover sites and migration habitats crucial to the long-term persistence of migrating shorebirds. Because of the tremendous variability in migrant shorebird occurrence patterns in the Prairie Pothole Region of the U.S. (Skagen 1997), it is labor- and cost-intensive to locate the majority of sites used heavily by shorebirds in any one migration period. Because WSR-88D (Weather Surveillance Radar – 1988 Doppler) or NEXRAD (NEXt generation weather RADar) has been useful for locating migrating birds and revealing migration patterns and important roosting sites of some species (e.g., Diehl and others 2003, Gauthreaux and Belser 2003), we undertook a pilot field study to determine wheTHER it also might be feasible to use NEXRAD for locating important stopover sites used by migrating shorebirds in the prairie potholes landscape. Coordinated efforts to advance the applicability of radar technology to bird conservation are underway (Ruth and others 2005).

Residency patterns of migrating sandpipers at a midcontinental stopover

USGS Publications Warehouse

Skagen, Susan K.; Knopf, Fritz L.

1994-01-01

Arctic-nesting shorebirds require several refueling stops during their long migrations between breeding grounds and Central and South American wintering areas. The protection of stopover habitats for transcontinental migrants depends on whether birds fly long distances between a few select sites or fly short distances and stop at several wetlands. Although the Great Plains historically provided a vast array of wetlands for use by migrants, wetland loss and conversion have reduced the availability of stopover sites in recent decades. In this study, we examined (1) residency periods, (2) fat dynamics, and (3) migration chronology of two shorebird species, the Semipalmated Sandpiper (Calidris pusilla) and White-rumped Sandpiper (C. fuscicollis) at Quivira National Wildlife Refuge (NWR), Kansas. Semipalmated Sandpipers had prolonged periods of species residency with overlapping arrivals and departures. Individual residency periods were highly variable and were unrelated to lipid reserves upon arrival. In contrast, White-rumped Sandpipers arrived and departed more synchronously. Birds that arrived in poor condition stayed longer than those with more body fat in 1991, but not in 1992. Wind direction did not influence patterns of departures of either species. We hypothesize that Semipalmated Sandpipers are ecologically eurytopic when migrating across the Great Plains in the spring. Highly variable patterns in arrival, residency, and lipid levels indicate that spring migration of this species is relaxed and opportunistic. White-rumped Sandpipers showed a pattern of reduced flexibility. Flight range estimates suggest that most birds require intermediate stopovers before reaching the breeding grounds. Interior wetlands appear to function as migration stopovers rather than staging areas for shorebirds.

A generalizable energetics-based model of avian migration to facilitate continental-scale waterbird conservation

USGS Publications Warehouse

Lonsdorf, Eric V.; Thogmartin, Wayne E.; Jacobi, Sarah; Coppen, Jorge; Davis, Amélie Y.; Fox, Timothy J.; Heglund, Patricia J.; Johnson, Rex; Jones, Tim; Kenow, Kevin P.; Lyons, James E.; Luke, Kirsten E.; Still, Shannon; Tavernia, Brian G.

2016-01-01

Conserving migratory birds is made especially difficult because of movement among spatially disparate locations across the annual cycle. In light of challenges presented by the scale and ecology of migratory birds, successful conservation requires integrating objectives, management, and monitoring across scales, from local management units to ecoregional and flyway administrative boundaries. We present an integrated approach using a spatially explicit energetic-based mechanistic bird migration model useful to conservation decision-making across disparate scales and locations. This model moves a mallard-like bird (Anas platyrhynchos), through spring and fall migration as a function of caloric gains and losses across a continental scale energy landscape. We predicted with this model that fall migration, where birds moved from breeding to wintering habitat, took a mean of 27.5 days of flight with a mean seasonal survivorship of 90.5% (95% CI = 89.2%, 91.9%) whereas spring migration took a mean of 23.5 days of flight with mean seasonal survivorship of 93.6% (95% CI = 92.5%, 94.7%). Sensitivity analyses suggested that survival during migration was sensitive to flight speed, flight cost, the amount of energy the animal could carry and the spatial pattern of energy availability, but generally insensitive to total energy availability per se. Nevertheless, continental patterns in the bird-use days occurred principally in relation to wetland cover and agricultural habitat in the fall. Bird-use days were highest in both spring and fall in the Mississippi Alluvial Valley and along the coast and near-shore environments of South Carolina. Spatial sensitivity analyses suggested that locations nearer to migratory endpoints were less important to survivorship; for instance, removing energy from a 1,036 km2 stopover site at a time from the Atlantic Flyway suggested coastal areas between New Jersey and North Carolina, including Chesapeake Bay and the North Carolina piedmont, are essential locations for efficient migration and increasing survivorship during spring migration but not locations in Ontario and Massachusetts. This sort of spatially explicit information may allow decision-makers to prioritize their conservation actions toward locations most influential to migratory success. Thus, this mechanistic model of avian migration provides a decision-analytic medium integrating the potential consequences of local actions to flyway-scale phenomena.

Patterns in diurnal airspace use by migratory landbirds along an ecological barrier.

PubMed

Peterson, Anna C; Niemi, Gerald J; Johnson, Douglas H

2015-04-01

Migratory bird populations and survival are affected by conditions experienced during migration. While many studies and conservation and management efforts focus on terrestrial stoppage and staging areas, the aerial environment through which migrants move also is subjected to anthropogenic impacts with potential consequences to migratory movement and survival. During autumn migration, the northern coastline of Lake Superior acts as an ecological barrier for many landbirds migrating out of the boreal forests of North America. From 24 observation points, we assessed the diurnal movements of birds throughout autumn migration, 2008-2010, within a 210 × 10 km coastal region along the northern coast of Lake Superior. Several raptor species showed patterns in airspace associated with topographic features such as proximity to the coastline and presence of ridgelines. Funneling movement, commonly used to describe the concentration of raptors along a migratory diversion line that either prevents or enhances migration progress, occurred only for Bald and Golden Eagles. This suggests a "leaky" migration funnel for most migratory raptors (e.g., migrating birds exiting the purported migration corridor). Passerines migrating during the late season showed more spatial and temporal structure in airspace distribution than raptors did, including funneling and an association with airspace near the coast. We conclude that (1) the diurnal use of airspace by many migratory landbirds is patterned in space and time, (2) autumn count sites situated along ecological barriers substantially underestimate the number of raptors due to "leakage" out of these concentration areas, and (3) the magnitude and structure of diurnal passerine movements in airspace have been overlooked. The heavy and structured use of airspace by migratory landbirds, especially the airspace associated with anthropogenic development (e.g., buildings, towers, turbines) necessitates a shift in focus to airspace management and conservation attention for these animals.

Patterns in diurnal airspace use by migratory landbirds along an ecological barrier

USGS Publications Warehouse

Peterson, Anna C.; Niemi, Gerald J.; Johnson, Douglas H.

2015-01-01

Migratory bird populations and survival are affected by conditions experienced during migration. While many studies and conservation and management efforts focus on terrestrial stoppage and staging areas, the aerial environment through which migrants move also is subjected to anthropogenic impacts with potential consequences to migratory movement and survival. During autumn migration, the northern coastline of Lake Superior acts as an ecological barrier for many landbirds migrating out of the boreal forests of North America. From 24 observation points, we assessed the diurnal movements of birds throughout autumn migration, 2008-2010, within a 210 km by 10 km coastal region along the northern coast of Lake Superior. Several raptor species showed patterns in airspace associated with topographic features such as proximity to the coastline and presence of ridgelines. Funneling movement, commonly used to describe the concentration of raptors along a migratory diversion line that either prevents or enhances migration progress, occurred only for Bald and Golden Eagles. This suggests a "leaky" migration funnel for most migratory raptors (e.g., migrating birds exiting the purported migration corridor). Passerines migrating during the late season showed more spatial and temporal structure in airspace distribution than raptors, including funneling and an association with airspace near the coast. We conclude that a) the diurnal use of airspace by many migratory landbirds is patterned in space and time, b) autumn count sites situated along ecological barriers substantially underestimate the number of raptors due to 'leakage' out of these concentration areas, and c) the magnitude and structure of diurnal passerine movements in airspace have been overlooked. The heavy and structured use of airspace by migratory landbirds, especially the airspace associated with anthropogenic development (e.g., buildings, towers, turbines) necessitates a shift in focus to airspace management and conservation attention for these animals.

Birds of Two Oceans? Trans-Andean and Divergent Migration of Black Skimmers (Rynchops niger cinerascens) from the Peruvian Amazon

PubMed Central

Davenport, Lisa C.

2016-01-01

Seasonal flooding compels some birds that breed in aquatic habitats in Amazonia to undertake annual migrations, yet we know little about how the complex landscape of the Amazon region is used seasonally by these species. The possibility of trans-Andes migration for Amazonian breeding birds has largely been discounted given the high geographic barrier posed by the Andean Cordillera and the desert habitat along much of the Pacific Coast. Here we demonstrate a trans-Andes route for Black Skimmers (Rynchops niger cinerascens) breeding on the Manu River (in the lowlands of Manu National Park, Perú), as well as divergent movement patterns both regionally and across the continent. Of eight skimmers tracked with satellite telemetry, three provided data on their outbound migrations, with two crossing the high Peruvian Andes to the Pacific. A third traveled over 1800 km to the southeast before transmissions ended in eastern Paraguay. One of the two trans-Andean migrants demonstrated a full round-trip migration back to its tagging location after traveling down the Pacific Coast from latitude 9° South to latitude 37° S, spending the austral summer in the Gulf of Arauco, Chile. This is the first documentation of a trans-Andes migration observed for any bird breeding in lowland Amazonia. To our knowledge, this research also documents the first example of a tropical-breeding waterbird migrating out of the tropics to spend the non-breeding season in the temperate summer, this being the reverse pattern with respect to seasonality for austral migrants in general. PMID:26760301

Birds of Two Oceans? Trans-Andean and Divergent Migration of Black Skimmers (Rynchops niger cinerascens) from the Peruvian Amazon.

PubMed

Davenport, Lisa C; Goodenough, Katharine S; Haugaasen, Torbjørn

2016-01-01

Seasonal flooding compels some birds that breed in aquatic habitats in Amazonia to undertake annual migrations, yet we know little about how the complex landscape of the Amazon region is used seasonally by these species. The possibility of trans-Andes migration for Amazonian breeding birds has largely been discounted given the high geographic barrier posed by the Andean Cordillera and the desert habitat along much of the Pacific Coast. Here we demonstrate a trans-Andes route for Black Skimmers (Rynchops niger cinerascens) breeding on the Manu River (in the lowlands of Manu National Park, Perú), as well as divergent movement patterns both regionally and across the continent. Of eight skimmers tracked with satellite telemetry, three provided data on their outbound migrations, with two crossing the high Peruvian Andes to the Pacific. A third traveled over 1800 km to the southeast before transmissions ended in eastern Paraguay. One of the two trans-Andean migrants demonstrated a full round-trip migration back to its tagging location after traveling down the Pacific Coast from latitude 9° South to latitude 37° S, spending the austral summer in the Gulf of Arauco, Chile. This is the first documentation of a trans-Andes migration observed for any bird breeding in lowland Amazonia. To our knowledge, this research also documents the first example of a tropical-breeding waterbird migrating out of the tropics to spend the non-breeding season in the temperate summer, this being the reverse pattern with respect to seasonality for austral migrants in general.

Using radar to advance migratory bird management: An interagency collaboration

USGS Publications Warehouse

Sojda, R.; Ruth, J.M.; Barrow, W.C.; Dawson, D.K.; Diehl, R.H.; Manville, A.; Green, M.T.; Krueper, D.J.; Johnston, S.

2005-01-01

Migratory birds face many changes to the landscapes they traverse and the habitats they use. Wind turbines and communications towers, which pose hazards to birds and bats in flight, are being erected across the United States and offshore. Human activities can also destroy or threaten habitats critical to birds during migratory passage, and climate change appears to be altering migratory patterns. The U.S. Fish and Wildlife Service (USFWS) and other agencies are under increasing pressure to identify and evaluate movement patterns and habitats used during migration and other times.

Geography of spring landbird migration through riparian habitats in southwestern North America

Treesearch

Susan K. Skagen; Jeffrey F. Kelly; Charles van Riper III; Richard L. Hutto; Deborah M. Finch; David J. Krueper; Cynthia P. Melcher

2005-01-01

Migration stopover resources, particularly riparian habitats, are critically important to landbirds migrating across the arid southwestern region of North America. To explore the effects of species biogeography and habitat affinity on spring migration patterns, we synthesized existing bird abundance and capture data collected in riparian habitats of the borderlands...

Eco-virological approach for assessing the role of wild birds in the spread of avian influenza H5N1 along the Central Asian Flyway.

PubMed

Newman, Scott H; Hill, Nichola J; Spragens, Kyle A; Janies, Daniel; Voronkin, Igor O; Prosser, Diann J; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M; Butler, Patrick J; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C; Takekawa, John Y

2012-01-01

A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this 'thoroughfare'. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005-2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations.

Space Based Ornithology: On the Wings of Migration and Biophysics

NASA Technical Reports Server (NTRS)

Smith, James A.

2005-01-01

The study of bird migration on a global scale is one of the compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties. Space based technology offers new opportunities to shed understanding on the distribution and migration of organisms on the planet and their sensitivity to human disturbances and environmental changes. Migration is an incredibly diverse and complex behavior. A broad outline of space based research must address three fundamental questions: (1) where could birds be, i.e. what is their fundamental niche constrained by their biophysical limits? (2) where do we actually find birds, i.e. what is their realizable niche as modified by local or regional abiotic and biotic factors, and (3) how do they get there (and how do we know?), that is what are their migration patterns and associated mechanisms? Our working hypothesis is that individual organism biophysical models of energy and water balance, driven by satellite measurements of spatio-temporal gradients in climate and habitat, will help us to explain the variability in avian species richness and distribution. Dynamic state variable modeling provides one tool for studying bird migration across multiple scales and can be linked to mechanistic models describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. Further these models provide an ecological forecasting tool for science and application users to address what are the possible consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration.

Birds, migration and emerging zoonoses: west nile virus, lyme disease, influenza A and enteropathogens.

PubMed

Reed, Kurt D; Meece, Jennifer K; Henkel, James S; Shukla, Sanjay K

2003-01-01

Wild birds are important to public health because they carry emerging zoonotic pathogens, either as a reservoir host or by dispersing infected arthropod vectors. In addition, bird migration provides a mechanism for the establishment of new endemic foci of disease at great distances from where an infection was acquired. Birds are central to the epidemiology of West Nile virus (WNV) because they are the main amplifying host of the virus in nature. The initial spread of WNV in the U.S. along the eastern seaboard coincided with a major bird migration corridor. The subsequent rapid movement of the virus inland could have been facilitated by the elliptical migration routes used by many songbirds. A number of bird species can be infected with Borrelia burgdorferi, the etiologic agent of Lyme disease, but most are not competent to transmit the infection to Ixodes ticks. The major role birds play in the geographic expansion of Lyme disease is as dispersers of B. burgdorferi-infected ticks. Aquatic waterfowl are asymptomatic carriers of essentially all hemagglutinin and neuraminidase combinations of influenza A virus. Avian influenza strains do not usually replicate well in humans, but they can undergo genetic reassortment with human strains that co-infect pigs. This can result in new strains with a marked increase in virulence for humans. Wild birds can acquire enteropathogens, such as Salmonella and Campylobacter spp., by feeding on raw sewage and garbage, and can spread these agents to humans directly or by contaminating commercial poultry operations. Conversely, wild birds can acquire drug-resistant enteropathogens from farms and spread these strains along migration routes. Birds contribute to the global spread of emerging infectious diseases in a manner analogous to humans traveling on aircraft. A better understanding of avian migration patterns and infectious diseases of birds would be useful in helping to predict future outbreaks of infections due to emerging zoonotic pathogens.

Comparative use of riparian corridors and oases by migrating birds in southeast Arizona

USGS Publications Warehouse

Skagen, S.K.; Melcher, Cynthia; Howe, W.H.; Knopf, F.L.

1998-01-01

The relative importance of cottonwood-willow riparian corridors and isolated oases to land birds migrating across southeastern Arizona was evaluated during four spring migrations, 1989 to 1994, based on patterns of species richness, relative abundance, density, and body condition of birds. We surveyed birds in 13 study sites ranging in size and connectivity from small isolated patches to extensive riparian forest, sampled vegetation and insects, and captured birds in mistnets. The continuous band of riparian vegetation along the San Pedro River does not appear to be functioning as a corridor for many migrating species, although it may for a few, namely Yellow-breasted Chats (Icteria virens), Summer Tanagers (Piranga rubra), and Northern Rough-winged Swallows (Steldigopteryx serripennis), which account for fewer than 10% of the individuals migrating through the area. Small, isolated oases hosted more avian species than the corridor sites, and the relative abundances of most migrating birds did not differ between sites relative to size-connectivity. There were few differences in between-year variability in the relative abundances of migrating birds between corridor and oasis sites. Between-year variability decreased with overall abundance of species and was greater for species with breeding ranges that centered north of 50??N latitude. Body condition of birds did not differ relative to the size-connectivity of the capture site, but individuals of species with more northerly breeding ranges had more body fat than species that breed nearby. Peak migration densities of several bird species far exceeded breeding densities reported for the San Pedro River, suggesting that large components of these species were en route migrants. Peak densities of Yellow Warblers (Dendroica petechia) reached 48.0 birds/ha, of Wilson's Warblers (Wilsonia pusilla) 33.7 birds/ha, and of Yellow-rumped Warblers (D. coronata) 30.1 birds/ha. Riparian vegetation is limited in extent in the vicinity of our study sites, covering less than 1% of the landscape. We conclude that all riparian patches in southeastern Arizona are important as stopover sites to en route migrants regardless of their size and degree of isolation or connectivity. In light of potential habitat limitation, the protection of both small, disjunct riparian patches and extensive riverine tracts in western landscapes is imperative.

Complex behaviour in complex terrain - Modelling bird migration in a high resolution wind field across mountainous terrain to simulate observed patterns.

PubMed

Aurbach, Annika; Schmid, Baptiste; Liechti, Felix; Chokani, Ndaona; Abhari, Reza

2018-06-03

Crossing of large ecological barriers, such as mountains, is in terms of energy considered to be a demanding and critical step during bird migration. Besides forming a geographical barrier, mountains have a profound impact on the resulting wind flow. We use a novel framework of mathematical models to investigate the influences of wind and topography on nocturnal passerine bird behaviour, and to assess the energy costs for different flight strategies for crossing the Jura Mountains. The mathematical models include three biological models of bird behaviour: i) wind drift compensation; ii) adaptation of flight height for favourable winds; and, iii) avoidance of obstacles (cross over and/or circumvention of an obstacle following a minimum energy expenditure strategy), which are assessed separately and in combination. Further, we use a mesoscale weather model for high-resolution predictions of the wind fields. We simulate the broad front nocturnal passerine migration for autumn nights with peak migration intensities. The bird densities retrieved from a weather radar are used as the initial intensities and to specify the vertical distributions of the simulated birds. It is shown that migration over complex terrain represents the most expensive flight option in terms of energy expenditure, and wind is seen to be the main factor that influences the energy expenditure in the bird's preferred flight direction. Further, the combined effects of wind and orography lead to a high concentration of migratory birds within the favourable wind conditions of the Swiss lowlands and north of the Jura Mountains. Copyright © 2018 Elsevier Ltd. All rights reserved.

Landbird migration in the American West: Recent progress and future research directions

USGS Publications Warehouse

Carlisle, J.D.; Skagen, S.K.; Kus, B.E.; van Riper, Charles; Paxton, K.L.; Kelly, J.F.

2009-01-01

Our knowledge of avian behaviors during the nonbreeding period still lags behind that of the breeding season, but the last decade has witnessed a proliferation in research that has yielded significant progress in understanding migration patterns of North American birds. And, although historically the great majority of migration research has been conducted in the eastern half of the continent, there has been much recent progress on aspects of avian migration in the West. In particular, expanded use of techniques such as radar, plasma metabolites, mist-netting, count surveys, stable isotopes, genetic data, and animal tracking, coupled with an increase in multi-investigator collaborations, have all contributed to this growth of knowledge. There is increasing recognition that migration is likely the most limiting time of year for migratory birds, increasing the importance of continuing to decipher patterns of stopover ecology, identifying critical stopover habitats, and documenting migration routes in the diverse and changing landscapes of the American West. Here, we review and briefly synthesize the latest findings and advances in avian migration and consider research needs to guide future research on migration in the West. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

Where in the air? Aerial habitat use of nocturnally migrating birds.

PubMed

Horton, Kyle G; Van Doren, Benjamin M; Stepanian, Phillip M; Farnsworth, Andrew; Kelly, Jeffrey F

2016-11-01

The lower atmosphere (i.e. aerosphere) is critical habitat for migrant birds. This habitat is vast and little is known about the spatio-temporal patterns of distribution and abundance of migrants in it. Increased human encroachment into the aerosphere makes understanding where and when migratory birds use this airspace a key to reducing human-wildlife conflicts. We use weather surveillance radar to describe large-scale height distributions of nocturnally migrating birds and interpret these distributions as aggregate habitat selection behaviours of individual birds. As such, we detail wind cues that influence selection of flight heights. Using six radars in the eastern USA during the spring (2013-2015) and autumn (2013 and 2014), we found migrants tended to adjust their heights according to favourable wind profit. We found that migrants' flight altitudes correlated most closely with the altitude of maximum wind profit; however, absolute differences in flight heights and height of maximum wind profit were large. Migrants tended to fly slightly higher at inland sites compared with coastal sites during spring, but not during autumn. Migration activity was greater at coastal sites during autumn, but not during spring. This characterization of bird migration represents a critical advance in our understanding of migrant distributions in flight and a new window into habitat selection behaviours. © 2016 The Author(s).

Where in the air? Aerial habitat use of nocturnally migrating birds

PubMed Central

Van Doren, Benjamin M.; Stepanian, Phillip M.; Farnsworth, Andrew; Kelly, Jeffrey F.

2016-01-01

The lower atmosphere (i.e. aerosphere) is critical habitat for migrant birds. This habitat is vast and little is known about the spatio-temporal patterns of distribution and abundance of migrants in it. Increased human encroachment into the aerosphere makes understanding where and when migratory birds use this airspace a key to reducing human–wildlife conflicts. We use weather surveillance radar to describe large-scale height distributions of nocturnally migrating birds and interpret these distributions as aggregate habitat selection behaviours of individual birds. As such, we detail wind cues that influence selection of flight heights. Using six radars in the eastern USA during the spring (2013–2015) and autumn (2013 and 2014), we found migrants tended to adjust their heights according to favourable wind profit. We found that migrants' flight altitudes correlated most closely with the altitude of maximum wind profit; however, absolute differences in flight heights and height of maximum wind profit were large. Migrants tended to fly slightly higher at inland sites compared with coastal sites during spring, but not during autumn. Migration activity was greater at coastal sites during autumn, but not during spring. This characterization of bird migration represents a critical advance in our understanding of migrant distributions in flight and a new window into habitat selection behaviours. PMID:27881761

Avian influenza H5N1 viral and bird migration networks in Asia

USGS Publications Warehouse

Tian, Huaivu; Zhou, Sen; Dong, Lu; Van Boeckel, Thomas P.; Cui, Yujun; Newman, Scott H.; Takekawa, John Y.; Prosser, Diann J.; Xiao, Xiangming; Wu, Yarong; Cazelles, Bernard; Huang, Shanqian; Yang, Ruifu; Grenfell, Bryan T.; Xu, Bing

2015-01-01

The spatial spread of the highly pathogenic avian influenza virus H5N1 and its long-term persistence in Asia have resulted in avian influenza panzootics and enormous economic losses in the poultry sector. However, an understanding of the regional long-distance transmission and seasonal patterns of the virus is still lacking. In this study, we present a phylogeographic approach to reconstruct the viral migration network. We show that within each wild fowl migratory flyway, the timing of H5N1 outbreaks and viral migrations are closely associated, but little viral transmission was observed between the flyways. The bird migration network is shown to better reflect the observed viral gene sequence data than other networks and contributes to seasonal H5N1 epidemics in local regions and its large-scale transmission along flyways. These findings have potentially far-reaching consequences, improving our understanding of how bird migration drives the periodic reemergence of H5N1 in Asia.

Avian influenza H5N1 viral and bird migration networks in Asia

PubMed Central

Tian, Huaiyu; Zhou, Sen; Dong, Lu; Van Boeckel, Thomas P.; Cui, Yujun; Newman, Scott H.; Takekawa, John Y.; Prosser, Diann J.; Xiao, Xiangming; Wu, Yarong; Cazelles, Bernard; Huang, Shanqian; Yang, Ruifu; Grenfell, Bryan T.; Xu, Bing

2015-01-01

The spatial spread of the highly pathogenic avian influenza virus H5N1 and its long-term persistence in Asia have resulted in avian influenza panzootics and enormous economic losses in the poultry sector. However, an understanding of the regional long-distance transmission and seasonal patterns of the virus is still lacking. In this study, we present a phylogeographic approach to reconstruct the viral migration network. We show that within each wild fowl migratory flyway, the timing of H5N1 outbreaks and viral migrations are closely associated, but little viral transmission was observed between the flyways. The bird migration network is shown to better reflect the observed viral gene sequence data than other networks and contributes to seasonal H5N1 epidemics in local regions and its large-scale transmission along flyways. These findings have potentially far-reaching consequences, improving our understanding of how bird migration drives the periodic reemergence of H5N1 in Asia. PMID:25535385

A preliminary investigation of bird classification by Doppler radar

NASA Technical Reports Server (NTRS)

Martinson, L. W.

1973-01-01

A preliminary study of the application of Doppler radar to the classification of birds is reported. The desirability for improvements in bird classification stems primarily from the hazards they present to jet aircraft in flight and in the vicinity of airports. A secondary need exists in the study of bird migration. The wing body and tail motion of a bird in flight reflect signals which, when analyzed properly present a signature of wing beat pattern which is unique for each bird species. Although the results of this investigation did not validate the feasibility of classifying bird species, they do indicate that a more thorough investigation is warranted. Certain gross characteristics such as wing beat rates, multiple bird patterns, and bird maneuverability, were indicated clearly in the results. Large birds with slow wing beat rates appear to be the most optimum subject for further study with the X-band Doppler radar used in this investigation.

Actogram analysis of free-flying migratory birds: new perspectives based on acceleration logging.

PubMed

Bäckman, Johan; Andersson, Arne; Pedersen, Lykke; Sjöberg, Sissel; Tøttrup, Anders P; Alerstam, Thomas

2017-07-01

The use of accelerometers has become an important part of biologging techniques for large-sized birds with accelerometer data providing information about flight mode, wing-beat pattern, behaviour and energy expenditure. Such data show that birds using much energy-saving soaring/gliding flight like frigatebirds and swifts can stay airborne without landing for several months. Successful accelerometer studies have recently been conducted also for free-flying small songbirds during their entire annual cycle. Here we review the principles and possibilities for accelerometer studies in bird migration. We use the first annual actograms (for red-backed shrike Lanius collurio) to explore new analyses and insights that become possible with accelerometer data. Actogram data allow precise estimates of numbers of flights, flight durations as well as departure/landing times during the annual cycle. Annual and diurnal rhythms of migratory flights, as well as prolonged nocturnal flights across desert barriers are illustrated. The shifting balance between flight, rest and different intensities of activity throughout the year as revealed by actogram data can be used to analyse exertion levels during different phases of the life cycle. Accelerometer recording of the annual activity patterns of individual birds will open up a new dimension in bird migration research.

Individual variation in staging and timing of spring migration of Pacific common eiders in Alaska

USGS Publications Warehouse

Petersen, Margaret R.

2005-01-01

Timing of migration and characterization of migration patterns of birds are usually based on dates of peak migration to and from staging, wintering, and breeding areas used by the bulk of a species. For Pacific common eiders (Somateria mollissima v-nigrum), as well as other species, the timing of migration into and through the Beaufort Sea is based on counts of birds past land or ice-based sites and radar observations, and arrival dates to colonies determined by influxes of birds seen by ground observers. With the continued and proposed development of nearshore and offshore waters of the Beaufort Sea, there is an expanding need to manage local populations. Observations of individual Pacific common eiders can provide a more complete understanding of local populations as well as variability among populations. This study was designed to determine factors influencing migration patterns of individuals nesting in the western Beaufort Sea from their wintering locations along the Chukotka Peninsula, through the eastern Chukchi and western Beaufort seas, until their arrival to their nesting area. The Simpson Lagoon/Maguire Island nesting colonies are 1300-1400 km from the primary winter area. Eiders enter the Beaufort Sea at Point Barrow then move east 300-350 km to their nesting colonies. Nesting adult females were marked with satellite transmitters during summer then followed the next spring and early summer. Transmitters were programmed to provide location data every 3 days (2001, n = 12) or daily (2002 and 2004, n = 7 and 18, respectively) beginning 15 April. I expected the dates of arrival to the colony to vary with weather during migration (Point. Barrow to the colony) and general conditions in spring (early or late year based on differences in temperatures from the long term norm for April, May, and June). All individuals returned to the colony area they were marked the previous year. Data were consistent with other “short” distance migrants. There were no correlations of the dates of arrival to the dates birds left the wintering area, the total days spent staging, wind speed or direction, temperature, weather, or seasonal differences in temperature from the long term average, a plethora of non-significant results. However, two patterns emerged: some birds migrated about 550 km and staged in the eastern Chukchi Sea before migrating to the colonies, while others went directly either to the colony area (1300 km) or elsewhere within the western  Beaufort. I will present preliminary analysis and several hypotheses regarding these two strategies. 

Modeling Bird Migration under Climate Change: A Mechanistic Approach

NASA Technical Reports Server (NTRS)

Smith, James A.

2009-01-01

How will migrating birds respond to changes in the environment under climate change? What are the implications for migratory success under the various accelerated climate change scenarios as forecast by the Intergovernmental Panel on Climate Change? How will reductions or increased variability in the number or quality of wetland stop-over sites affect migratory bird species? The answers to these questions have important ramifications for conservation biology and wildlife management. Here, we describe the use of continental scale simulation modeling to explore how spatio-temporal changes along migratory flyways affect en-route migration success. We use an individually based, biophysical, mechanistic, bird migration model to simulate the movement of shorebirds in North America as a tool to study how such factors as drought and wetland loss may impact migratory success and modify migration patterns. Our model is driven by remote sensing and climate data and incorporates important landscape variables. The energy budget components of the model include resting, foraging, and flight, but presently predation is ignored. Results/Conclusions We illustrate our model by studying the spring migration of sandpipers through the Great Plains to their Arctic breeding grounds. Why many species of shorebirds have shown significant declines remains a puzzle. Shorebirds are sensitive to stop-over quality and spacing because of their need for frequent refueling stops and their opportunistic feeding patterns. We predict bird "hydrographs that is, stop-over frequency with latitude, that are in agreement with the literature. Mean stop-over durations predicted from our model for nominal cases also are consistent with the limited, but available data. For the shorebird species simulated, our model predicts that shorebirds exhibit significant plasticity and are able to shift their migration patterns in response to changing drought conditions. However, the question remains as to whether this behavior can be maintained over increasing and sustained environmental change. Also, the problem is much more complex than described by the current processes captured in our model. We have taken some important and interesting steps, and our model does demonstrate how local scale information about individual stop-over sites can be linked into the migratory flyway as a whole. We are incorporating additional, species specific, mechanistic processes to better reflect different climate change scenarios

Proximate cues for a short-distance migratory species: An application of survival analysis

USGS Publications Warehouse

Meunier, J.; Song, R.; Lutz, R.S.; Andersen, D.E.; Doherty, K.E.; Bruggink, J.G.; Oppelt, E.

2008-01-01

Investigation of bird migration has often highlighted the importance of external factors in determining timing of migration However, little distinction has been made between short- and long-distance migrants and between local and flight birds (passage migrants) in describing migration chronology. In addition, measures of food abundance as a proximate factor influencing timing of migration are lacking in studies of migration chronology. To address the relationship between environmental variables and timing of migration we quantified the relative importance of proximate external factors on migration chronology of local American woodcock (Scolopax minor), a short distance migrant, using event-time analysis methods (survival analysis). We captured 1,094 woodcock local to our study sites in Michigan, Minnesota and Wisconsin (USA) during autumn 2002-2004 and documented 786 departure dates for these birds. Photoperiod appeared to provide an initial proximate cue for timing of departure. Moon phase was important in modifying timing of departure, which may serve as a navigational aid in piloting and possibly orientation. Local synoptic weather variables also contributed to timing of departure by changing the rate of departure from our study sites. We found no evidence that food availability influenced timing of woodcock departure. Our results suggest that woodcock use a conservative photoperiod-controlled strategy with proximate modifiers for timing of migration rather than relying on abundance of their primary food, earthworms. Managing harvest pressure on local birds by adjusting season lengths may be an effective management tool with consistent migration patterns from year to year based on photoperiod.

Temporal changes in the structure of a plant-frugivore network are influenced by bird migration and fruit availability

PubMed Central

Andresen, Ellen; Díaz-Castelazo, Cecilia

2016-01-01

Background. Ecological communities are dynamic collections whose composition and structure change over time, making up complex interspecific interaction networks. Mutualistic plant–animal networks can be approached through complex network analysis; these networks are characterized by a nested structure consisting of a core of generalist species, which endows the network with stability and robustness against disturbance. Those mutualistic network structures can vary as a consequence of seasonal fluctuations and food availability, as well as the arrival of new species into the system that might disorder the mutualistic network structure (e.g., a decrease in nested pattern). However, there is no assessment on how the arrival of migratory species into seasonal tropical systems can modify such patterns. Emergent and fine structural temporal patterns are adressed here for the first time for plant-frugivorous bird networks in a highly seasonal tropical environment. Methods. In a plant-frugivorous bird community, we analyzed the temporal turnover of bird species comprising the network core and periphery of ten temporal interaction networks resulting from different bird migration periods. Additionally, we evaluated how fruit abundance and richness, as well as the arrival of migratory birds into the system, explained the temporal changes in network parameters such as network size, connectance, nestedness, specialization, interaction strength asymmetry and niche overlap. The analysis included data from 10 quantitative plant-frugivorous bird networks registered from November 2013 to November 2014. Results. We registered a total of 319 interactions between 42 plant species and 44 frugivorous bird species; only ten bird species were part of the network core. We witnessed a noteworthy turnover of the species comprising the network periphery during migration periods, as opposed to the network core, which did not show significant temporal changes in species composition. Our results revealed that migration and fruit richness explain the temporal variations in network size, connectance, nestedness and interaction strength asymmetry. On the other hand, fruit abundance only explained connectance and nestedness. Discussion. By means of a fine-resolution temporal analysis, we evidenced for the first time how temporal changes in the interaction network structure respond to the arrival of migratory species into the system and to fruit availability. Additionally, few migratory bird species are important links for structuring networks, while most of them were peripheral species. We showed the relevance of studying bird–plant interactions at fine temporal scales, considering changing scenarios of species composition with a quantitative network approach. PMID:27330852

Eco-virological approach for assessing the role of wild birds in the spread of avian influenza H5N1 along the central Asian flyway

USGS Publications Warehouse

Newman, Scott H.; Hill, Nichola J.; Spragens, Kyle A.; Janies, Daniel; Voronkin, Igor O.; Prosser, Diann J.; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M.; Butler, Patrick J.; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C.; Takekawa, John Y.

2012-01-01

A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this ‘thoroughfare’. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005–2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations.

Eco-Virological Approach for Assessing the Role of Wild Birds in the Spread of Avian Influenza H5N1 along the Central Asian Flyway

PubMed Central

Newman, Scott H.; Hill, Nichola J.; Spragens, Kyle A.; Janies, Daniel; Voronkin, Igor O.; Prosser, Diann J.; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M.; Butler, Patrick J.; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C.; Takekawa, John Y.

2012-01-01

A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this ‘thoroughfare’. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005–2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations. PMID:22347393

Soaring Migratory Birds Avoid Wind Farm in the Isthmus of Tehuantepec, Southern Mexico

PubMed Central

Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A.; Herrera-Alsina, Leonel

2014-01-01

The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region. PMID:24647442

Soaring migratory birds avoid wind farm in the Isthmus of Tehuantepec, southern Mexico.

PubMed

Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A; Herrera-Alsina, Leonel

2014-01-01

The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region.

Intercontinental migratory connectivity and population structuring of Dunlins from western Alaska

USGS Publications Warehouse

Gill, Robert E.; Handel, Colleen M.; Ruthrauff, Daniel R.

2013-01-01

The Dunlin (Calidris alpina) is a polytypic shorebird with complex patterns of distribution and migration throughout its holarctic range. We analyzed mark-re sighting data obtained between 1977 and 2010 from birds captured at two major staging areas in western Alaska to test the hypothesis that the migration patterns of Alaskan populations are a mixture of parallel and chain, similar to those of Dunlin populations in the western Palearctic. Birds marked on the Yukon—Kuskokwim Delta were found wintering in both Asia and North America, which documented the unexpected mixing of C. a. arcticola from northern Alaska and C. a. pacifica from western Alaska and contradicted our initial prediction of parallel migration pathways for these two subspecies. In its North American winter range C. a. pacifica segregated according to location of marking, confirming our prediction of a chain migration pattern within this population. Individuals of C. a. pacifica marked on the delta were resighted significantly farther north, mostly in southern British Columbia and Washington, than birds marked on the second, more southerly staging area on the Alaska Peninsula, which were resighted primarily in the San Francisco Bay area of northern California. We recommend additional studies use a combination of intrinsic and extrinsic markers to quantify the strength of migratory connectivity between breeding, staging, and wintering areas. Such information is needed to guide conservation efforts because the Dunlin and other waterbirds are losing intertidal habitats at an unprecedented rate and scale, particularly in the Yellow Sea and other parts of Asia.

First description of autumn migration of Sooty Falcon Falco concolor from the United Arab Emirates to Madagascar using satellite telemetry

USGS Publications Warehouse

Javed, Sàlim; Douglas, David C.; Khan, Shahid Noor; Nazeer Shah, Junid; Ali Al Hammadi, Abdullah

2012-01-01

The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon's autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

Migratory bird pathways and the Gulf of Mexico: Importance of Louisiana's coast

USGS Publications Warehouse

Smith, Gregory J.; Barrow, Wylie

2005-01-01

Because of its geographic position, Louisiana plays an important role in the hemispheric-scale phenomenon known as the Nearctic-Neotropical bird migration system. Each year millions of landbirds migrate across or near to the coast of the Gulf of Mexico. Birds migrate in large, broad fronts that sometimes exceed 2 million individuals, and there is an advantage for them to take a direct north-south route (the shortest distance).During migration seasons, nearly all of the migratory landbird species of the eastern United States, as well as many western species, use the coastal plains of the western gulf.Spring migrants arrive with depleted energy reserves and depend on Louisiana's coastal habitats to provide food and cover after long gulf crossings.Fall migrants depend on Louisiana’s coastal habitats for food to store fat reserves just prior to gulf crossings in autumn.Mortality during the migratory period can be high. Recent research on the black-throated blue warbler (Dendroica caerulescens) indicates that more than 85% of the annual mortality for the species occurs during migration.Migrants en route tend to concentrate in habitats adjacent to ecological barriers; DOI land managers need to identify key coastal landscape features that are important to these birds.Because of the vastness of the North American continent, it is nearly impossible to delineate movement patterns and migration pathways by using traditional ground-based surveys.

Links between scale and neotropical migratory bird populations

Treesearch

Deborah M. Finch

1994-01-01

Recent concerns about the future for migratory birds, particularly those that migrate to the Tropics, have led to the development of a variety of new research and education initiatives addressing avian population ecology and conservation. Research that focuses on the relationships between migrant population trends, geographical patterns, and spatial and temporal scales...

Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

NASA Astrophysics Data System (ADS)

Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

2016-08-01

The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

Status and migration of the Southwestern willow flycatcher in New Mexico

Treesearch

Deborah M. Finch; Jeffrey F. Kelly

1999-01-01

In the Southwestern United States, recent degradation of riparian habitats has been linked to decline of the Southwestern subspecies of the Willow Flycatcher. During a 2-year banding effort, migration patterns and bird fat content were analyzed. Recommendations for managers, and outlines for conservation plans, are included.

A landscape scale decision support tool for monitoring bird and bat migration across Wisconsin

USGS Publications Warehouse

Suarez, Manuel J.; Heglund, Patricia J.; Kratt, Robert; Kirsch, Eileen

2008-01-01

This project was initiated to begin addressing the question, “Are there patterns in timing, location, and direction among migrating landbirds?” that have been at the forefront of discussion with our Federal, State, and County partners with regard to siting wind energy projects. Our goal was to explore the use of Nexrad weather data to see if examining 5 or more years’ worth of data would provide us with a sense of the general timing, movement patterns and habitat use by migrating landbirds.

Shorebird Migration Patterns in Response to Climate Change: A Modeling Approach

NASA Technical Reports Server (NTRS)

Smith, James A.

2010-01-01

The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies offer new opportunities for the application of mechanistic models to predict how continental scale bird migration patterns may change in response to environmental change. In earlier studies, we explored the phenotypic plasticity of a migratory population of Pectoral sandpipers by simulating the movement patterns of an ensemble of 10,000 individual birds in response to changes in stopover locations as an indicator of the impacts of wetland loss and inter-annual variability on the fitness of migratory shorebirds. We used an individual based, biophysical migration model, driven by remotely sensed land surface data, climate data, and biological field data. Mean stop-over durations and stop-over frequency with latitude predicted from our model for nominal cases were consistent with results reported in the literature and available field data. In this study, we take advantage of new computing capabilities enabled by recent GP-GPU computing paradigms and commodity hardware (general purchase computing on graphics processing units). Several aspects of our individual based (agent modeling) approach lend themselves well to GP-GPU computing. We have been able to allocate compute-intensive tasks to the graphics processing units, and now simulate ensembles of 400,000 birds at varying spatial resolutions along the central North American flyway. We are incorporating additional, species specific, mechanistic processes to better reflect the processes underlying bird phenotypic plasticity responses to different climate change scenarios in the central U.S.

Storms drive altitudinal migration in a tropical bird

PubMed Central

Boyle, W. Alice; Norris, D. Ryan; Guglielmo, Christopher G.

2010-01-01

Although migration is a widespread and taxonomically diverse behaviour, the ecological factors shaping migratory behaviour are poorly understood. Like other montane taxa, many birds migrate along elevational gradients in the tropics. Forty years ago, Alexander Skutch postulated that severe storms could drive birds to migrate downhill. Here, we articulate a novel mechanism that could link storms to mortality risks via reductions in foraging time and provide, to our knowledge, the first tests of this hypothesis in the White-ruffed Manakin (Corapipo altera), a small partially migratory frugivore breeding on the Atlantic slope of Costa Rica. As predicted, variation in rainfall was associated with plasma corticosterone levels, fat stores, plasma metabolites and haematocrit. By collecting data at high and low elevation sites simultaneously, we also found that high-elevation residents were more adversely affected by storms than low elevation migrants. These results, together with striking temporal capture patterns of altitudinal migrants relative to storms, provide, to our knowledge, the first evidence that weather-related risks incurred by species requiring high food intake rates can explain altitudinal migrations of tropical animals. These findings resolve conflicting evidence for and against food limitation being important in the evolution of this behaviour, and highlight how endogenous and exogenous processes influence life-history trade-offs made by individuals in the wild. Because seasonal storms are a defining characteristic of most tropical ecosystems and rainfall patterns will probably change in ensuing decades, these results have important implications for understanding the ecology, evolution and conservation of tropical animals. PMID:20375047

Storms drive altitudinal migration in a tropical bird.

PubMed

Boyle, W Alice; Norris, D Ryan; Guglielmo, Christopher G

2010-08-22

Although migration is a widespread and taxonomically diverse behaviour, the ecological factors shaping migratory behaviour are poorly understood. Like other montane taxa, many birds migrate along elevational gradients in the tropics. Forty years ago, Alexander Skutch postulated that severe storms could drive birds to migrate downhill. Here, we articulate a novel mechanism that could link storms to mortality risks via reductions in foraging time and provide, to our knowledge, the first tests of this hypothesis in the White-ruffed Manakin (Corapipo altera), a small partially migratory frugivore breeding on the Atlantic slope of Costa Rica. As predicted, variation in rainfall was associated with plasma corticosterone levels, fat stores, plasma metabolites and haematocrit. By collecting data at high and low elevation sites simultaneously, we also found that high-elevation residents were more adversely affected by storms than low elevation migrants. These results, together with striking temporal capture patterns of altitudinal migrants relative to storms, provide, to our knowledge, the first evidence that weather-related risks incurred by species requiring high food intake rates can explain altitudinal migrations of tropical animals. These findings resolve conflicting evidence for and against food limitation being important in the evolution of this behaviour, and highlight how endogenous and exogenous processes influence life-history trade-offs made by individuals in the wild. Because seasonal storms are a defining characteristic of most tropical ecosystems and rainfall patterns will probably change in ensuing decades, these results have important implications for understanding the ecology, evolution and conservation of tropical animals.

Quantifying full phenological event distributions reveals simultaneous advances, temporal stability and delays in spring and autumn migration timing in long-distance migratory birds.

PubMed

Miles, Will T S; Bolton, Mark; Davis, Peter; Dennis, Roy; Broad, Roger; Robertson, Iain; Riddiford, Nick J; Harvey, Paul V; Riddington, Roger; Shaw, Deryk N; Parnaby, David; Reid, Jane M

2017-04-01

Phenological changes in key seasonally expressed life-history traits occurring across periods of climatic and environmental change can cause temporal mismatches between interacting species, and thereby impact population and community dynamics. However, studies quantifying long-term phenological changes have commonly only measured variation occurring in spring, measured as the first or mean dates on which focal traits or events were observed. Few studies have considered seasonally paired events spanning spring and autumn or tested the key assumption that single convenient metrics accurately capture entire event distributions. We used 60 years (1955-2014) of daily bird migration census data from Fair Isle, Scotland, to comprehensively quantify the degree to which the full distributions of spring and autumn migration timing of 13 species of long-distance migratory bird changed across a period of substantial climatic and environmental change. In most species, mean spring and autumn migration dates changed little. However, the early migration phase (≤10th percentile date) commonly got earlier, while the late migration phase (≥90th percentile date) commonly got later. Consequently, species' total migration durations typically lengthened across years. Spring and autumn migration phenologies were not consistently correlated within or between years within species and hence were not tightly coupled. Furthermore, different metrics quantifying different aspects of migration phenology within seasons were not strongly cross-correlated, meaning that no single metric adequately described the full pattern of phenological change. These analyses therefore reveal complex patterns of simultaneous advancement, temporal stability and delay in spring and autumn migration phenologies, altering species' life-history structures. Additionally, they demonstrate that this complexity is only revealed if multiple metrics encompassing entire seasonal event distributions, rather than single metrics, are used to quantify phenological change. Existing evidence of long-term phenological changes detected using only one or two metrics should consequently be interpreted cautiously because divergent changes occurring simultaneously could potentially have remained undetected. © 2016 John Wiley & Sons Ltd.

Stripes and belly-spots – a review of pigment cell morphogenesis in vertebrates

PubMed Central

Kelsh, Robert N.; Harris, Melissa L.; Colanesi, Sarah; Erickson, Carol A.

2009-01-01

Pigment patterns in the integument have long-attracted attention from both scientists and non-scientists alike since their natural attractiveness combines with their excellence as models for the general problem of pattern formation. Pigment cells are formed from the neural crest and must migrate to reach their final locations. In this review, we focus on our current understanding of mechanisms underlying the control of pigment cell migration and patterning in diverse vertebrates. The model systems discussed here –chick, mouse, and zebrafish – each provide unique insights into the major morphogenetic events driving pigment pattern formation. In birds and mammals, melanoblasts must be specified before they can migrate on the dorsolateral pathway. Transmembrane receptors involved in guiding them onto this route include EphB2 and Ednrb2 in chick, and Kit in mouse. Terminal migration depends, in part, upon extracellular matrix reorganization by ADAMTS20. Invasion of the ectoderm, especially into the feather germ and hair follicles, requires specific signals that are beginning to be characterized. We summarize our current understanding of the mechanisms regulating melanoblast number and organization in the epidermis. We note the apparent differences in pigment pattern formation in poikilothermic vertebrates when compared with birds and mammals. With more pigment cell types, migration pathways are more complex and largely unexplored; nevertheless, a role for Kit signaling in melanophore migration is clear and indicates that at least some patterning mechanisms may be highly conserved. We summarize the multiple factors thought to contribute to zebrafish embryonic pigment pattern formation, highlighting a recent study identifying Sdf1a as one factor crucial for regulation of melanophore positioning. Finally, we discuss the mechanisms generating a second, metamorphic pigment pattern in adult fish, emphasizing recent studies strengthening the evidence that undifferentiated progenitor cells play a major role in generating adult pigment cells. PMID:18977309

Bird migration patterns in the arid southwest-Final report

USGS Publications Warehouse

Ruth, Janet M.; Felix, Rodney K.; Dieh, Robert H.

2010-01-01

To ensure full life-cycle conservation, we need to understand migrant behavior en route and how migrating species use stopover and migration aerohabitats. In the Southwest, birds traverse arid and mountainous landscapes in migration. Migrants are known to use riparian stopover habitats; we know less about how migrant density varies across the Southwest seasonally and annually, and how migrants use other habitat types during migratory stopover. Furthermore, we lack information about migrant flight altitudes, speeds, and directions of travel, and how these patterns vary seasonally and annually across the Southwest. Using weather surveillance radar data, we identified targets likely dominated by nocturnally migrating birds and determined their flight altitudes, speeds, directions over ground, and variations in abundance. Migrating or foraging bats likely are present across the region in some of these data, particularly in central Texas. We found that migrants flew at significantly lower altitudes and significantly higher speeds in spring than in fall. In all seasons migrants maintained seasonally appropriate directions of movement. We detected significant differences in vertical structure of migrant densities that varied both geographically within seasons and seasonally within sites. We also found that in fall there was a greater and more variable passage of migrants through the central part of the borderlands (New Mexico and west Texas); in spring there was some suggestion of greater and more variable passage of migrants in the eastern borderlands (central and south Texas). Such patterns are consistent with the existence of at least two migration systems through western North America and the use of different migration routes in spring and fall for at least some species. Using radar data and satellite land cover data, we determined the habitats with which migrants are associated during migration stopover. There were significant differences in bird densities among habitat types at all sites in at least one season. Upland forest habitat in parts of Arizona and New Mexico supported high migrant densities, especially in fall. Developed habitats in areas with little upland forest habitat also supported high migrant densities. Scrub/shrub and grassland habitats supported low to intermediate migrant densities, but because these habitat types dominate the region, they may support large numbers of migratory birds. This may be especially true for species that do not use forested habitats during migration. Target identity remains a challenge for radar-based studies. Presence of bats in the data complicates interpretation of some observations, particularly from central Texas. Based on our results it is simplistic to: (1) consider the arid west as a largely inhospitable landscape in which there are only relatively small oases of habitat that provide the resources needed by all migrants; (2) think of western riparian and upland forest habitat as supporting the majority of migrants in all cases; or (3) consider a particular habitat type unimportant migrant stopover habitat based solely on migrant densities.

Intercontinental spread of Asian-origin H5N8 to North America through Beringia by migratory birds

USDA-ARS?s Scientific Manuscript database

Phylogenetic analysis and understanding of the waterfowl migration patterns suggests that Eurasian H5N8 clade 2.3.4.4 viruses moved to the Russian Far East/Beringia via migratory birds in spring 2014, evolved into 2 subgroups and subsequently spread along different flyways during fall 2014 into Euro...

Animal migration and risk of spread of viral infections: Chapter 9

USGS Publications Warehouse

Prosser, Diann J.; Nagel, Jessica; Takekawa, John Y.; Edited by Singh, Sunit K.

2013-01-01

The potential contribution of migration towards the spread of disease is as varied as the ecology of the pathogens themselves and their host populations. This chapter outlines multiple examples of viral diseases in animal populations and their mechanisms of viral spread. Many species of insects, mammals, fish, and birds exhibit migratory behavior and have the potential to disperse diseases over long distances. The majority of studies available on viral zoonoses have focused on birds and bats, due to their highly migratory life histories. A number of studies have reported evidence of changes in the timing of animal migrations in response to climate change. The majority indicate an advancement of spring migration, with few or inconclusive results for fall migration. Predicting the combined effects of climate change on migratory patterns of host species and epidemiology of viral pathogens is complex and not fully realistic.

Navigating north: how body mass and winds shape avian flight behaviours across a North American migratory flyway.

PubMed

Horton, Kyle G; Van Doren, Benjamin M; La Sorte, Frank A; Fink, Daniel; Sheldon, Daniel; Farnsworth, Andrew; Kelly, Jeffrey F

2018-05-07

The migratory patterns of birds have been the focus of ecologists for millennia. What behavioural traits underlie these remarkably consistent movements? Addressing this question is central to advancing our understanding of migratory flight strategies and requires the integration of information across levels of biological organisation, e.g. species to communities. Here, we combine species-specific observations from the eBird citizen-science database with observations aggregated from weather surveillance radars during spring migration in central North America. Our results confirm a core prediction of migration theory at an unprecedented national scale: body mass predicts variation in flight strategies across latitudes, with larger-bodied species flying faster and compensating more for wind drift. We also find evidence that migrants travelling northward earlier in the spring increasingly compensate for wind drift at higher latitudes. This integration of information across biological scales provides new insight into patterns and determinants of broad-scale flight strategies of migratory birds. © 2018 John Wiley & Sons Ltd/CNRS.

Role of wild birds as carriers of multi-drug resistant Escherichia coli and Escherichia vulneris

PubMed Central

Shobrak, Mohammed Y.; Abo-Amer, Aly E.

2014-01-01

Emergence and distribution of multi-drug resistant (MDR) bacteria in environments pose a risk to human and animal health. A total of 82 isolates of Escherichia spp. were recovered from cloacal swabs of migrating and non-migrating wild birds. All bacterial isolates were identified and characterized morphologically and biochemically. 72% and 50% of isolates recovered from non-migrating and migrating birds, respectively, showed positive congo red dye binding (a virulence factor). Also, hemolysin production (a virulence factor) was showed in 8% of isolates recovered from non-migrating birds and 75% of isolates recovered from migrating birds. All isolates recovered from non-migrating birds were found resistant to Oxacillin while all isolates recovered from migrating birds demonstrated resistance to Oxacillin, Chloramphenicol, Oxytetracycline and Lincomycin. Some bacterial isolates recovered from non-migrating birds and migrating birds exhibited MDR phenotype. The MDR isolates were further characterized by API 20E and 16S rRNA as E. coli and E. vulneris. MDR Escherichia isolates contain ~1–5 plasmids of high-molecular weights. Accordingly, wild birds could create a potential threat to human and animal health by transmitting MDR bacteria to water streams and other environmental sources through their faecal residues, and to remote regions by migration. PMID:25763023

Variable detours in long-distance migration across ecological barriers and their relation to habitat availability at ground

PubMed Central

Hahn, Steffen; Emmenegger, Tamara; Lisovski, Simeon; Amrhein, Valentin; Zehtindjiev, Pavel; Liechti, Felix

2014-01-01

Migration detours, the spatial deviation from the shortest route, are a widespread phenomenon in migratory species, especially if barriers must be crossed. Moving longer distances causes additional efforts in energy and time, and to be adaptive, this should be counterbalanced by favorable condition en route. We compared migration patterns of nightingales that travelled along different flyways from their European breeding sites to the African nonbreeding sites. We tested for deviations from shortest routes and related the observed and expected routes to the habitat availability at ground during autumn and spring migration. All individuals flew detours of varying extent. Detours were largest and seasonally consistent in western flyway birds, whereas birds on the central and eastern flyways showed less detours during autumn migration, but large detours during spring migration (eastern flyway birds). Neither migration durations nor the time of arrival at destination were related to the lengths of detours. Arrival at the breeding site was nearly synchronous in birds flying different detours. Flying detours increased the potential availability of suitable broad-scale habitats en route only along the western flyway. Habitat availability on observed routes remained similar or even decreased for individuals flying detours on the central or the eastern flyway as compared to shortest routes. Thus, broad-scale habitat distribution may partially explain detour performance, but the weak detour-habitat association along central and eastern flyways suggests that other factors shape detour extent regionally. Prime candidate factors are the distribution of small suitable habitat patches at local scale as well as winds specific for the region and altitude. PMID:25505540

Wild waterfowl migration and domestic duck density shape the epidemiology of highly pathogenic H5N8 influenza in the Republic of Korea

PubMed Central

Hill, Sarah C.; Lee, Youn-Jeong; Song, Byung-Min; Kang, Hyun-Mi; Lee, Eun-Kyoung; Hanna, Amanda; Gilbert, Marius; Brown, Ian H.; Pybus, Oliver G.

2015-01-01

Highly pathogenic avian influenza (HPAI) viruses threaten human and animal health yet their emergence is poorly understood, partly because sampling of the HPAI Asian-origin H5N1 lineage immediately after its identification in 1996 was comparatively sparse. The discovery of a novel H5N8 virus in 2013 provides a new opportunity to investigate HPAI emergence in greater detail. Here we investigate the origin and transmission of H5N8 in the Republic of Korea, the second country to report the new strain. We reconstruct viral spread using phylogeographic methods and interpret the results in the context of ecological data on poultry density, overwintering wild bird numbers, and bird migration patterns. Our results indicate that wild waterfowl migration and domestic duck density were important to H5N8 epidemiology. Specifically, we infer that H5N8 entered the Republic of Korea via Jeonbuk province, then spread rapidly among western provinces where densities of overwintering waterfowl and domestic ducks are higher, yet rarely persisted in eastern regions. The common ancestor of H5N8 in the Republic of Korea was estimated to have arrived during the peak of inward migration of overwintering birds. Recent virus isolations likely represent re-introductions via bird migration from an as-yet unsampled reservoir. Based on the limited data from outside the Republic of Korea, our data suggest that H5N8 may have entered Europe at least twice, and Asia at least three times from this reservoir, most likely carried by wild migrating birds. PMID:26079277

Wild waterfowl migration and domestic duck density shape the epidemiology of highly pathogenic H5N8 influenza in the Republic of Korea.

PubMed

Hill, Sarah C; Lee, Youn-Jeong; Song, Byung-Min; Kang, Hyun-Mi; Lee, Eun-Kyoung; Hanna, Amanda; Gilbert, Marius; Brown, Ian H; Pybus, Oliver G

2015-08-01

Highly pathogenic avian influenza (HPAI) viruses threaten human and animal health yet their emergence is poorly understood, partly because sampling of the HPAI Asian-origin H5N1 lineage immediately after its identification in 1996 was comparatively sparse. The discovery of a novel H5N8 virus in 2013 provides a new opportunity to investigate HPAI emergence in greater detail. Here we investigate the origin and transmission of H5N8 in the Republic of Korea, the second country to report the new strain. We reconstruct viral spread using phylogeographic methods and interpret the results in the context of ecological data on poultry density, overwintering wild bird numbers, and bird migration patterns. Our results indicate that wild waterfowl migration and domestic duck density were important to H5N8 epidemiology. Specifically, we infer that H5N8 entered the Republic of Korea via Jeonbuk province, then spread rapidly among western provinces where densities of overwintering waterfowl and domestic ducks are higher, yet rarely persisted in eastern regions. The common ancestor of H5N8 in the Republic of Korea was estimated to have arrived during the peak of inward migration of overwintering birds. Recent virus isolations likely represent re-introductions via bird migration from an as-yet unsampled reservoir. Based on the limited data from outside the Republic of Korea, our data suggest that H5N8 may have entered Europe at least twice, and Asia at least three times from this reservoir, most likely carried by wild migrating birds. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Webcams for Bird Detection and Monitoring: A Demonstration Study

PubMed Central

Verstraeten, Willem W.; Vermeulen, Bart; Stuckens, Jan; Lhermitte, Stefaan; Van der Zande, Dimitry; Van Ranst, Marc; Coppin, Pol

2010-01-01

Better insights into bird migration can be a tool for assessing the spread of avian borne infections or ecological/climatologic issues reflected in deviating migration patterns. This paper evaluates whether low budget permanent cameras such as webcams can offer a valuable contribution to the reporting of migratory birds. An experimental design was set up to study the detection capability using objects of different size, color and velocity. The results of the experiment revealed the minimum size, maximum velocity and contrast of the objects required for detection by a standard webcam. Furthermore, a modular processing scheme was proposed to track and follow migratory birds in webcam recordings. Techniques such as motion detection by background subtraction, stereo vision and lens distortion were combined to form the foundation of the bird tracking algorithm. Additional research to integrate webcam networks, however, is needed and future research should enforce the potential of the processing scheme by exploring and testing alternatives of each individual module or processing step. PMID:22319308

Webcams for bird detection and monitoring: a demonstration study.

PubMed

Verstraeten, Willem W; Vermeulen, Bart; Stuckens, Jan; Lhermitte, Stefaan; Van der Zande, Dimitry; Van Ranst, Marc; Coppin, Pol

2010-01-01

Better insights into bird migration can be a tool for assessing the spread of avian borne infections or ecological/climatologic issues reflected in deviating migration patterns. This paper evaluates whether low budget permanent cameras such as webcams can offer a valuable contribution to the reporting of migratory birds. An experimental design was set up to study the detection capability using objects of different size, color and velocity. The results of the experiment revealed the minimum size, maximum velocity and contrast of the objects required for detection by a standard webcam. Furthermore, a modular processing scheme was proposed to track and follow migratory birds in webcam recordings. Techniques such as motion detection by background subtraction, stereo vision and lens distortion were combined to form the foundation of the bird tracking algorithm. Additional research to integrate webcam networks, however, is needed and future research should enforce the potential of the processing scheme by exploring and testing alternatives of each individual module or processing step.

Stopover ecology of neotropical migrants in central Veracruz, México

Treesearch

Ernesto Ruelas Inzunza; Stephen W. Hoffman; Laurie J. Goodrich

2005-01-01

Available information on the ecology of neotropical migrants during the winter season and especially during migration is far behind the existing knowledge of birds during the breeding season. This paper presents a stopover ecology case study. We document the occurrence of species, outline the prevailing weather patterns during spring and fall migration seasons, and...

Potential Impacts of Extended Winter Navigation upon Migratory Birds of the Upper U.S. Great Lakes. Great Lakes-St. Lawrence Seaway Navigation Season Extension Program

DTIC Science & Technology

1982-09-01

pattern in the beaching rate is caused mostly by high mortality of young gulls in late summer and fall before and during migration. Almost no oiling of...Most Frequently Beached Birds From 1978 to 1980 . . . . . . . . . 167 54 Age Composition of Beached Ring-billed Gulls . . . . . . . . . . 168 55 Age... Composition of Beached Herring Gulls . . . . . . . . . . . . 169 ix LIST OF TABLES (continued) B16 Summary of Selected Birds Present on Christmas

The relationship between annual survival rate and migration distance in mallards: an examination of the time-allocation hypothesis for the evolution of migration

USGS Publications Warehouse

Hestbeck, J.B.; Nichols, J.D.; Hines, J.E.

1992-01-01

Predictions of the time-allocation hypothesis were tested with several a posteriori analyses of banding data for the mallard (Anas platyrhynchos). The time-allocation hypothesis states that the critical difference between resident and migrant birds is their allocation of time to reproduction on the breeding grounds and survival on the nonbreeding grounds. Residents have higher reproduction and migrants have higher survival. Survival and recovery rates were estimated by standard band-recovery methods for banding reference areas in the central United States and central Canada. A production-rate index was computed for each reference area with data from the U.S. Fish and Wildlife Service May Breeding Population Survey and July Production Survey. An analysis of covariance was used to test for the effects of migration distance and time period (decade) on survival, recovery, and production rates. Differences in migration chronology were tested by comparing direct-recovery distributions for different populations during the fall migration. Differences in winter locations were tested by comparing distributions of direct recoveries reported during December and January. A strong positive relationship was found between survival rate, and migration distance for 3 of the 4 age and sex classes. A weak negative relationship was found between recovery rate and migration distance. No relationship was found between production rate and migration distance. During the fall migration, birds from the northern breeding populations were located north of birds from the southern breeding populations. No pattern could be found in the relative locations of breeding and wintering areas. Although our finding that survival rate increased with migration distance was consistent with the time-allocation hypothesis, our results on migration chronology and location of wintering areas were not consistent with the mechanism underlying the time-allocation hypothesis. Neither this analysis nor other recent studies of life-history characteristics of migratory and resident birds supported the timeallocation hypothesis.

Bird Migration Under Climate Change - A Mechanistic Approach Using Remote Sensing

NASA Technical Reports Server (NTRS)

Smith, James A.; Blattner, Tim; Messmer, Peter

2010-01-01

The broad-scale reductions and shifts that may be expected under climate change in the availability and quality of stopover habitat for long-distance migrants is an area of increasing concern for conservation biologists. Researchers generally have taken two broad approaches to the modeling of migration behaviour to understand the impact of these changes on migratory bird populations. These include models based on causal processes and their response to environmental stimulation, "mechanistic models", or models that primarily are based on observed animal distribution patterns and the correlation of these patterns with environmental variables, i.e. "data driven" models. Investigators have applied the latter technique to forecast changes in migration patterns with changes in the environment, for example, as might be expected under climate change, by forecasting how the underlying environmental data layers upon which the relationships are built will change over time. The learned geostatstical correlations are then applied to the modified data layers.. However, this is problematic. Even if the projections of how the underlying data layers will change are correct, it is not evident that the statistical relationships will remain the same, i.e. that the animal organism may not adapt its' behaviour to the changing conditions. Mechanistic models that explicitly take into account the physical, biological, and behaviour responses of an organism as well as the underlying changes in the landscape offer an alternative to address these shortcomings. The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies enable the application of the mechanistic models to predict how continental bird migration patterns may change in response to environmental change. In earlier work, we simulated the impact of effects of wetland loss and inter-annual variability on the fitness of migratory shorebirds in the central fly ways of North America. We demonstrated the phenotypic plasticity of a migratory population of Pectoral sandpipers consisting of an ensemble of 10,000 individual birds in response to changes in stopover locations using an individual based migration model driven by remotely sensed land surface data, climate data and biological field data. With the advent of new computing capabilities enabled hy recent GPU-GP computing paradigms and commodity hardware, it now is possible to simulate both larger ensemble populations and to incorporate more realistic mechanistic factors into migration models. Here, we take our first steps use these tools to study the impact of long-term drought variability on shorebird survival.

Using Citizen Science Observations to Model Species Distributions Over Space, Through Time, and Across Scales

NASA Astrophysics Data System (ADS)

Kelling, S.

2017-12-01

The goal of Biodiversity research is to identify, explain, and predict why a species' distribution and abundance vary through time, space, and with features of the environment. Measuring these patterns and predicting their responses to change are not exercises in curiosity. Today, they are essential tasks for understanding the profound effects that humans have on earth's natural systems, and for developing science-based environmental policies. To gain insight about species' distribution patterns requires studying natural systems at appropriate scales, yet studies of ecological processes continue to be compromised by inadequate attention to scale issues. How spatial and temporal patterns in nature change with scale often reflects fundamental laws of physics, chemistry, or biology, and we can identify such basic, governing laws only by comparing patterns over a wide range of scales. This presentation will provide several examples that integrate bird observations made by volunteers, with NASA Earth Imagery using Big Data analysis techniques to analyze the temporal patterns of bird occurrence across scales—from hemisphere-wide views of bird distributions to the impact of powerful city lights on bird migration.

Ocean-wide Drivers of Migration Strategies and Their Influence on Population Breeding Performance in a Declining Seabird.

PubMed

Fayet, Annette L; Freeman, Robin; Anker-Nilssen, Tycho; Diamond, Antony; Erikstad, Kjell E; Fifield, Dave; Fitzsimmons, Michelle G; Hansen, Erpur S; Harris, Mike P; Jessopp, Mark; Kouwenberg, Amy-Lee; Kress, Steve; Mowat, Stephen; Perrins, Chris M; Petersen, Aevar; Petersen, Ib K; Reiertsen, Tone K; Robertson, Gregory J; Shannon, Paula; Sigurðsson, Ingvar A; Shoji, Akiko; Wanless, Sarah; Guilford, Tim

2017-12-18

Which factors shape animals' migration movements across large geographical scales, how different migratory strategies emerge between populations, and how these may affect population dynamics are central questions in the field of animal migration [1] that only large-scale studies of migration patterns across a species' range can answer [2]. To address these questions, we track the migration of 270 Atlantic puffins Fratercula arctica, a red-listed, declining seabird, across their entire breeding range. We investigate the role of demographic, geographical, and environmental variables in driving spatial and behavioral differences on an ocean-basin scale by measuring puffins' among-colony differences in migratory routes and day-to-day behavior (estimated with individual daily activity budgets and energy expenditure). We show that competition and local winter resource availability are important drivers of migratory movements, with birds from larger colonies or with poorer local winter conditions migrating further and visiting less-productive waters; this in turn led to differences in flight activity and energy expenditure. Other behavioral differences emerge with latitude, with foraging effort and energy expenditure increasing when birds winter further north in colder waters. Importantly, these ocean-wide migration patterns can ultimately be linked with breeding performance: colony productivity is negatively associated with wintering latitude, population size, and migration distance, which demonstrates the cost of competition and migration on future breeding and the link between non-breeding and breeding periods. Our results help us to understand the drivers of animal migration and have important implications for population dynamics and the conservation of migratory species. Copyright © 2017 Elsevier Ltd. All rights reserved.

Altitudinal patterns in breeding bird species richness and density in relation to climate, habitat heterogeneity, and migration influence in a temperate montane forest (South Korea).

PubMed

Kim, Jin-Yong; Lee, Sanghun; Shin, Man-Seok; Lee, Chang-Hoon; Seo, Changwan; Eo, Soo Hyung

2018-01-01

Altitudinal patterns in the population ecology of mountain bird species are useful for predicting species occurrence and behavior. Numerous hypotheses about the complex interactions among environmental factors have been proposed; however, these still remain controversial. This study aimed to identify the altitudinal patterns in breeding bird species richness or density and to test the hypotheses that climate, habitat heterogeneity (horizontal and vertical), and heterospecific attraction in a temperate forest, South Korea. We conducted a field survey of 142 plots at altitudes between 200 and 1,400 m a.s.l in the breeding season. A total of 2,771 individuals from 53 breeding bird species were recorded. Altitudinal patterns of species richness and density showed a hump-shaped pattern, indicating that the highest richness and density could be observed at moderate altitudes. Models constructed with 13 combinations of six variables demonstrated that species richness was positively correlated with vertical and horizontal habitat heterogeneity. Density was positively correlated with vertical, but not horizontal habitat heterogeneity, and negatively correlated with migratory bird ratio. No significant relationships were found between spring temperature and species richness or density. Therefore, the observed patterns in species richness support the hypothesis that habitat heterogeneity, rather than climate, is the main driver of species richness. Also, neither habitat heterogeneity nor climate hypotheses fully explains the observed patterns in density. However, vertical habitat heterogeneity does likely help explain observed patterns in density. The heterospecific attraction hypothesis did not apply to the distribution of birds along the altitudinal gradient. Appropriate management of vertical habitat heterogeneity, such as vegetation cover, should be maintained for the conservation of bird diversity in this area.

Energy efficiency drives the global seasonal distribution of birds.

PubMed

Somveille, Marius; Rodrigues, Ana S L; Manica, Andrea

2018-06-01

The uneven distribution of biodiversity on Earth is one of the most general and puzzling patterns in ecology. Many hypotheses have been proposed to explain it, based on evolutionary processes or on constraints related to geography and energy. However, previous studies investigating these hypotheses have been largely descriptive due to the logistical difficulties of conducting controlled experiments on such large geographical scales. Here, we use bird migration-the seasonal redistribution of approximately 15% of bird species across the world-as a natural experiment for testing the species-energy relationship, the hypothesis that animal diversity is driven by energetic constraints. We develop a mechanistic model of bird distributions across the world, and across seasons, based on simple ecological and energetic principles. Using this model, we show that bird species distributions optimize the balance between energy acquisition and energy expenditure while taking into account competition with other species. These findings support, and provide a mechanistic explanation for, the species-energy relationship. The findings also provide a general explanation of migration as a mechanism that allows birds to optimize their energy budget in the face of seasonality and competition. Finally, our mechanistic model provides a tool for predicting how ecosystems will respond to global anthropogenic change.

Age ratios and their possible use in determining autumn routes of passerine migrants

Treesearch

C. John Ralph

1981-01-01

Age ratios and abundance of 61 migrant passerine species comprising more than 42,000 birds were analyzed in an attempt to determine patterns of migration. The data were collected at 10 stations from coastal Massachusetts to inland Pennsylvania. Age ratios are thought to be useful in determining routes of migration. The principal criteria for the edge of a species...

Patterns of testosterone in three Nearctic-Neotropical migratory songbirds during spring passage.

PubMed

Covino, Kristen M; Morris, Sara R; Moore, Frank R

2015-12-01

Preparation for breeding may overlap extensively with vernal migration in long-distance migratory songbirds. Testosterone plays a central role in mediating this transition into breeding condition by facilitating changes to physiology and behavior. While changes in testosterone levels are well studied in captive migrants, these changes are less well known in free-living birds. We examined testosterone levels in free-living Nearctic-Neotropical migrants of three species during their vernal migration. Testosterone levels increased during the migratory period in males of all three species but significantly so in only two. Testosterone levels in females remained the same throughout their migration. Our results support the extensive overlap between vernal migration and breeding preparation in male songbirds. The pattern of testosterone changes during vernal migration is far from clear in females. Copyright © 2015 Elsevier Inc. All rights reserved.

Rice production systems and avian influenza: Interactions between mixed-farming systems, poultry and wild birds

USGS Publications Warehouse

Muzaffar, S.B.; Takekawa, John Y.; Prosser, D.J.; Newman, S.H.; Xiao, X.

2010-01-01

Wild waterfowl are the reservoir for avian influenza viruses (AIVs), a family of RNA viruses that may cause mild sickness in waterbirds. Emergence of H5N1, a highly pathogenic avian influenza (HPAI) strain, causing severe disease and mortality in wild birds, poultry and humans, had raised concerns about the role of wild birds in possible transmission of the disease. In this review, the link between rice production systems, poultry production systems, and wild bird ecology is examined to assess the extent to which these interactions could contribute towards the persistence and evolution of HPAI H5N1. The rice (Oryza sativa) and poultry production systems in Asia described, and then migration and movements of wild birds discussed. Mixed farming systems in Asia and wild bird movement and migration patterns create opportunities for the persistence of low pathogenic AIVs in these systems. Nonetheless, there is no evidence of long-term persistence of HPAI viruses (including the H5N1 subtype) in the wild. There are still significant gaps in the understanding of how AIVs circulate in rice systems. A better understanding of persistence of AIVs in rice farms, particularly of poultry origins, is essential in limiting exchange of AIVs between mixed-farming systems, poultry and wild birds.

Effects of weather on the abundance and distribution on populations of 103 breeding bird species across the United States

NASA Astrophysics Data System (ADS)

Allstadt, A. J.; Gorzo, J.; Bateman, B. L.; Heglund, P. J.; Pidgeon, A. M.; Thogmartin, W.; Vavrus, S. J.; Radeloff, V.

2016-12-01

Often, fewer birds are often observed in an area experiencing extreme weather, as local populations tend to leave an area (via out-migration or concentration in refugia) or experience a change in population size (via mortality or reduced fecundity). Further, weather patterns are often coherent over large areas so unsuitable weather may threaten large portions of an entire species range simultaneously. However, beyond a few iconic irruptive species, rarely have studies applied both the necessary scale and sensitivity required to assess avian population responses over entire species range. Here, we examined the effects of pre-breeding season weather on the distribution and abundances of 103 North American bird species from the late 1966-2010 using observed abundance records from the Breeding Bird Survey. We compared abundances with measures of drought and temperature over each species' range, and with three atmospheric teleconnections that describe large-scale circulation patterns influencing conditions on the ground. More than 90% of the species responded to at least one of our five weather variables. Grassland bird species tended to be most responsive to weather conditions and forest birds the least, though we found relations among all habitat types. For most species, the response was movement rather than large effects on the overall population size. Maps of these responses indicate that concentration and out-migration are both common strategies for coping with challenging weather conditions across a species range. The dynamic distribution of many bird species makes clear the need to account for temporal variability in conservation planning, as areas that are less important for a species' breeding success in most years may be very important in years with abnormal weather conditions.

Methods of quantitative and qualitative analysis of bird migration with a tracking radar

NASA Technical Reports Server (NTRS)

Bruderer, B.; Steidinger, P.

1972-01-01

Methods of analyzing bird migration by using tracking radar are discussed. The procedure for assessing the rate of bird passage is described. Three topics are presented concerning the grouping of nocturnal migrants, the velocity of migratory flight, and identification of species by radar echoes. The height and volume of migration under different weather conditions are examined. The methods for studying the directions of migration and the correlation between winds and the height and direction of migrating birds are presented.

Bird species migration ratio in East Asia, Australia, and surrounding islands.

PubMed

Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

2013-08-01

Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

Bird species migration ratio in East Asia, Australia, and surrounding islands

NASA Astrophysics Data System (ADS)

Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

2013-08-01

Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

Linking animals aloft with the terrestrial landscape

USGS Publications Warehouse

Buler, Jeffrey J.; Barrow, Wylie; Boone, Matthew; Dawson, Deanna K.; Diehl, Robert H.; Moore, Frank R.; Randall, Lori A.; Schreckengost, Timothy; Smolinsky, Jaclyn A.

2018-01-01

Despite using the aerosphere for many facets of their life, most flying animals (i.e., birds, bats, some insects) are still bound to terrestrial habitats for resting, feeding, and reproduction. Comprehensive broad-scale observations by weather surveillance radars of animals as they leave terrestrial habitats for migration or feeding flights can be used to map their terrestrial distributions either as point locations (e.g., communal roosts) or as continuous surface layers (e.g., animal densities in habitats across a landscape). We discuss some of the technical challenges to reducing measurement biases related to how radars sample the aerosphere and the flight behavior of animals. We highlight a recently developed methodological approach that precisely and quantitatively links the horizontal spatial structure of birds aloft to their terrestrial distributions and provides novel insights into avian ecology and conservation across broad landscapes. Specifically, we present case studies that (1) elucidate how migrating birds contend with crossing ecological barriers and extreme weather events, (2) identify important stopover areas and habitat use patterns of birds along their migration routes, and (3) assess waterfowl response to wetland habitat management and restoration. These studies aid our understanding of how anthropogenic modification of the terrestrial landscape (e.g., urbanization, habitat management), natural geographic features, and weather (e.g., hurricanes) can affect the terrestrial distributions of flying animals.

Mass dynamics of wintering Pacific Black Brant: Body, adipose tissue, organ, and muscle masses vary with location

USGS Publications Warehouse

Mason, D.D.; Barboza, P.S.; Ward, D.H.

2007-01-01

We compared body size and mass of the whole body, organs, adipose tissue, and muscles of adult Pacific Black Brant (Branta bernicla nigricans (Lawrence, 1846)) collected concurrently in Alaska and Baja California during the fall, winter, and spring of 2002–2003. Head and tarsal lengths of males were similar between sites and slightly larger for females in Alaska than in Baja California. Brant appear to operate under similar physiological bounds, but patterns of nutrient allocation differ between sites. Birds wintering in Alaska lost similar amounts of adipose tissue during early winter as birds in Baja California gained during late winter before migration. Masses of the body, adipose tissue, and flight muscles during mid-winter were similar between sites. Seasonal adipose tissue deposition may, therefore, equally favor winter residency or long-distance migration. Gonad and liver masses increased in late winter for birds in Alaska but not for those in Baja California, suggesting birds wintering in Baja may delay reproductive development in favor of allocating reserves needed for migration. Phenotypic flexibility allows Brant to use widely divergent wintering sites. The wintering location of Brant likely depends more upon changes in environmental conditions and food availability, than upon physiological differences between the two wintering populations.

Bioacoustic monitoring of nocturnal songbird migration in a southern great lakes ecosystem

NASA Astrophysics Data System (ADS)

Sanders, Claire Elizabeth

Many species of birds produce short vocalizations during nocturnal migration. My thesis uses bioacoustic monitoring of these night flight calls to study bird migration through a southern Great Lakes ecosystem. I deployed recording devices around western Lake Erie during spring and fall migrations. Analysis of thousands of hours of recordings revealed that night flight calls accurately predicted both the magnitude of migration, as well as the timing of migrant passage, as assessed by banding. The first arrival dates for 48 species of migratory birds were significantly earlier on Pelee Island than on mainland Ontario in the spring. More flight calls were detected over Pelee Island than over mainland comparison sites. These results suggest that many birds cross Lake Erie in spring and fall, and that islands are important for migratory birds. This research provides insight into the use of acoustics for monitoring birds in active migration.

Climate as a driver of continent-wide irruptions in boreal seed-eating birds (Invited)

NASA Astrophysics Data System (ADS)

Strong, C.; Zuckerberg, B.; Betancourt, J. L.

2013-12-01

Boreal seed-eating birds regularly breed and overwinter throughout Canada and Alaska, but every few years these species demonstrate impressive irruptive migrations out of the boreal forest and into more southerly regions. It is thought that irruptive migrations are inversely dependent on a circumboreally synchronized pattern of seed crop fluctuations in boreal trees; seed-eating boreal birds stay in the north when food is plentiful, but sojourn south when food is scarce. Because both seed production and bird irruptions are characterized by periodicity ranging from biennial to decadal cycles, there is a strong possibility that these ecological phenomena are driven by climate variability. Using over twenty years of data from Project FeederWatch (a national citizen science project), we found that 'super irruptions' are correlated with continent-wide irruptive events in pine siskin population, and that these irruptions are associated with multi-decadal climate variability of Pacific origin. We also investigate how climate variability may influence the distribution of boreal bird species across different regions of North America during winter, and evaluate results in the context of limited banding data to assess possible geographic pathways of irruptions.

The ontogenetic development of orientation capabilities

NASA Technical Reports Server (NTRS)

Emlen, S. T.

1972-01-01

The effects of celestial references on the navigation ability of birds are discussed. Tests were conducted in a planetarium with indigo buntings to determine the amount of stellar pattern which could be removed before disorientation occurred. It was determined that young birds have a predisposition to respond to the apparent rotational motion of the night sky. It was concluded that the peak in responsiveness to rotational information is presented during the first summer of life, prior to the first migration season.

Modeling the Distribution of Migratory Bird Stopovers to Inform Landscape-Scale Siting of Wind Development

PubMed Central

Pocewicz, Amy; Estes-Zumpf, Wendy A.; Andersen, Mark D.; Copeland, Holly E.; Keinath, Douglas A.; Griscom, Hannah R.

2013-01-01

Conservation of migratory birds requires understanding the distribution of and potential threats to their migratory habitats. However, although migratory birds are protected under international treaties, few maps have been available to represent migration at a landscape scale useful to target conservation efforts or inform the siting of wind energy developments that may affect migratory birds. To fill this gap, we developed models that predict where four groups of birds concentrate or stopover during their migration through the state of Wyoming, USA: raptors, wetland, riparian and sparse grassland birds. The models were based on existing literature and expert knowledge concerning bird migration behavior and ecology and validated using expert ratings and known occurrences. There was significant agreement between migratory occurrence data and migration models for all groups except raptors, and all models ranked well with experts. We measured the overlap between the migration concentration models and a predictive model of wind energy development to assess the potential exposure of migratory birds to wind development and illustrate the utility of migratory concentration models for landscape-scale planning. Wind development potential is high across 15% of Wyoming, and 73% of this high potential area intersects important migration concentration areas. From 5.2% to 18.8% of each group’s important migration areas was represented within this high wind potential area, with the highest exposures for sparse grassland birds and the lowest for riparian birds. Our approach could be replicated elsewhere to fill critical data gaps and better inform conservation priorities and landscape-scale planning for migratory birds. PMID:24098379

Ocean Surface Winds Drive Dynamics of Transoceanic Aerial Movements

PubMed Central

Felicísimo, Ángel M.; Muñoz, Jesús; González-Solis, Jacob

2008-01-01

Global wind patterns influence dispersal and migration processes of aerial organisms, propagules and particles, which ultimately could determine the dynamics of colonizations, invasions or spread of pathogens. However, studying how wind-mediated movements actually happen has been hampered so far by the lack of high resolution global wind data as well as the impossibility to track aerial movements. Using concurrent data on winds and actual pathways of a tracked seabird, here we show that oceanic winds define spatiotemporal pathways and barriers for large-scale aerial movements. We obtained wind data from NASA SeaWinds scatterometer to calculate wind cost (impedance) models reflecting the resistance to the aerial movement near the ocean surface. We also tracked the movements of a model organism, the Cory's shearwater (Calonectris diomedea), a pelagic bird known to perform long distance migrations. Cost models revealed that distant areas can be connected through “wind highways” that do not match the shortest great circle routes. Bird routes closely followed the low-cost “wind-highways” linking breeding and wintering areas. In addition, we found that a potential barrier, the near surface westerlies in the Atlantic sector of the Intertropical Convergence Zone (ITCZ), temporally hindered meridional trans-equatorial movements. Once the westerlies vanished, birds crossed the ITCZ to their winter quarters. This study provides a novel approach to investigate wind-mediated movements in oceanic environments and shows that large-scale migration and dispersal processes over the oceans can be largely driven by spatiotemporal wind patterns. PMID:18698354

Ocean surface winds drive dynamics of transoceanic aerial movements.

PubMed

Felicísimo, Angel M; Muñoz, Jesús; González-Solis, Jacob

2008-08-13

Global wind patterns influence dispersal and migration processes of aerial organisms, propagules and particles, which ultimately could determine the dynamics of colonizations, invasions or spread of pathogens. However, studying how wind-mediated movements actually happen has been hampered so far by the lack of high resolution global wind data as well as the impossibility to track aerial movements. Using concurrent data on winds and actual pathways of a tracked seabird, here we show that oceanic winds define spatiotemporal pathways and barriers for large-scale aerial movements. We obtained wind data from NASA SeaWinds scatterometer to calculate wind cost (impedance) models reflecting the resistance to the aerial movement near the ocean surface. We also tracked the movements of a model organism, the Cory's shearwater (Calonectris diomedea), a pelagic bird known to perform long distance migrations. Cost models revealed that distant areas can be connected through "wind highways" that do not match the shortest great circle routes. Bird routes closely followed the low-cost "wind-highways" linking breeding and wintering areas. In addition, we found that a potential barrier, the near surface westerlies in the Atlantic sector of the Intertropical Convergence Zone (ITCZ), temporally hindered meridional trans-equatorial movements. Once the westerlies vanished, birds crossed the ITCZ to their winter quarters. This study provides a novel approach to investigate wind-mediated movements in oceanic environments and shows that large-scale migration and dispersal processes over the oceans can be largely driven by spatiotemporal wind patterns.

The role of the antioxidant system during intense endurance exercise: lessons from migrating birds.

PubMed

Cooper-Mullin, Clara; McWilliams, Scott R

2016-12-01

During migration, birds substantially increase their metabolic rate and burn fats as fuel and yet somehow avoid succumbing to overwhelming oxidative damage. The physiological means by which vertebrates such as migrating birds can counteract an increased production of reactive species (RS) are rather limited: they can upregulate their endogenous antioxidant system and/or consume dietary antioxidants (prophylactically or therapeutically). Thus, birds can alter different components of their antioxidant system to respond to the demands of long-duration flights, but much remains to be discovered about the complexities of RS production and antioxidant protection throughout migration. Here, we use bird migration as an example to discuss how RS are produced during endurance exercise and how the complex antioxidant system can protect against cellular damage caused by RS. Understanding how a bird's antioxidant system responds during migration can lend insights into how antioxidants protect birds during other life-history stages when metabolic rate may be high, and how antioxidants protect other vertebrates from oxidative damage during endurance exercise. © 2016. Published by The Company of Biologists Ltd.

Toward conservation of midcontinental shorebird migrations

USGS Publications Warehouse

Skagen, Susan K.; Knopf, Fritz L.

1993-01-01

Shorebirds represent a highly diverse group of species, many of which experience tremendous energy demands associated with long-distance migratory flights. Transcontinental migrants are dependant upon dynamic freshwater wetlands for stopover resources essential for replenishment of lipid reserves and completion of migration. Patterns of shorebird migration across midcontinental wetlands were detected from migration reports to American Birds and information provided by U.S. Fish and Wildlife Service national wildlife refuges. Patterns in species composition and abundance varied geographically, emphasizing the uniqueness of different regions to migrating shorebirds. Smaller species and neotropical migrants moved primarily across the Great Plains, whereas larger species and North American migrants predominated in assemblages in the intermountain west. Shorebirds were broadly dispersed in wetland habitats with dynamic water regimes. Whereas populations of shorebirds in coastal system appear to concentrate at sites of seasonally predictable and abundant food resources, we propose that transcontinental shorebirds disperse and use wetlands opportunistically. This migration system exemplifies the need for large-scale, coordinated regional management efforts that recognize the dynamic nature of ecosystem processes.

Mites (family Trombiculidae) parasitizing birds migrating from Africa to Europe

PubMed Central

Varma, M. G. R.

1964-01-01

The mechanisms of dissemination of arthropod-borne human and animal pathogens are of considerable interest to the epidemiologist, veterinarian and biologist. Birds which are hosts to such pathogens and their arthropod vectors could transport them over long distances during their spring and autumn migratory flights. In April 1961, birds migrating from Africa to Europe were collected in south-western Spain and examined for ectoparasites and antibodies to arboviruses. Fully engorged larvae of two species of trombiculid mites unknown in Europe (genera Neoschoengastia and Blankaartia) but found in Africa were collected from two of the migrating birds (redstart and little bittern), suggesting that the birds were carrying the mites from Africa to Europe. Trombiculid mites are the proven vectors of scrub typhus; they have also been implicated in the transmission of human haemorrhagic nephroso-nephritis. The finding of the mite larvae on migrating birds is therefore of some epidemiological interest and underlines the importance of obtaining more data on the dispersal of trombiculids by migrating birds. PMID:14267750

The effects of urbanization on migrating birds on the western shore of Lake Michigan

EPA Science Inventory

Urbanization continues to transform the global landscape at an alarming rate, yet most ecological studies focus on more natural ecosystems. Many cities lie within major flyways for migrating birds, and our knowledge of how urbanization affects migrating birds is severely lacking....

Bird migration flight altitudes studied by a network of operational weather radars.

PubMed

Dokter, Adriaan M; Liechti, Felix; Stark, Herbert; Delobbe, Laurent; Tabary, Pierre; Holleman, Iwan

2011-01-06

A fully automated method for the detection and quantification of bird migration was developed for operational C-band weather radar, measuring bird density, speed and direction as a function of altitude. These weather radar bird observations have been validated with data from a high-accuracy dedicated bird radar, which was stationed in the measurement volume of weather radar sites in The Netherlands, Belgium and France for a full migration season during autumn 2007 and spring 2008. We show that weather radar can extract near real-time bird density altitude profiles that closely correspond to the density profiles measured by dedicated bird radar. Doppler weather radar can thus be used as a reliable sensor for quantifying bird densities aloft in an operational setting, which--when extended to multiple radars--enables the mapping and continuous monitoring of bird migration flyways. By applying the automated method to a network of weather radars, we observed how mesoscale variability in weather conditions structured the timing and altitude profile of bird migration within single nights. Bird density altitude profiles were observed that consisted of multiple layers, which could be explained from the distinct wind conditions at different take-off sites. Consistently lower bird densities are recorded in The Netherlands compared with sites in France and eastern Belgium, which reveals some of the spatial extent of the dominant Scandinavian flyway over continental Europe.

Bird migration flight altitudes studied by a network of operational weather radars

PubMed Central

Dokter, Adriaan M.; Liechti, Felix; Stark, Herbert; Delobbe, Laurent; Tabary, Pierre; Holleman, Iwan

2011-01-01

A fully automated method for the detection and quantification of bird migration was developed for operational C-band weather radar, measuring bird density, speed and direction as a function of altitude. These weather radar bird observations have been validated with data from a high-accuracy dedicated bird radar, which was stationed in the measurement volume of weather radar sites in The Netherlands, Belgium and France for a full migration season during autumn 2007 and spring 2008. We show that weather radar can extract near real-time bird density altitude profiles that closely correspond to the density profiles measured by dedicated bird radar. Doppler weather radar can thus be used as a reliable sensor for quantifying bird densities aloft in an operational setting, which—when extended to multiple radars—enables the mapping and continuous monitoring of bird migration flyways. By applying the automated method to a network of weather radars, we observed how mesoscale variability in weather conditions structured the timing and altitude profile of bird migration within single nights. Bird density altitude profiles were observed that consisted of multiple layers, which could be explained from the distinct wind conditions at different take-off sites. Consistently lower bird densities are recorded in The Netherlands compared with sites in France and eastern Belgium, which reveals some of the spatial extent of the dominant Scandinavian flyway over continental Europe. PMID:20519212

Migration patterns and movements of sandhill cranes wintering in central and southwestern Louisiana

USGS Publications Warehouse

King, Sammy L.; Pierce, Aaron R.; Hersey, Kent R.; Winstead, Nicholas; Hartup, Barry K.

2010-01-01

In this study we trapped wintering sandhill cranes (Grus canadensis) in Louisiana and fitted them with satellite transmitters to determine their migration routes. Four of the 6 sandhill cranes with validated locations and a terminus point used the Central Flyway for spring migration; 2 of these 4 (the only 2 for which we have data) also used the Central Flyway for fall migration. Two of the 6 birds used the Mississippi Flyway for spring migration. The results of this study suggest that reintroduced whooping cranes (G. americana) that intermix and migrate with sandhill cranes that winter in Louisiana may enter the Central Flyway. In addition, the Mississippi Flyway is a viable option to use as a migration route for whooping cranes if they are reintroduced in Louisiana.

Flyway-scale variation in plasma triglyceride levels as an index of refueling rate in spring-migrating western sandpipers (Calidris mauri)

USGS Publications Warehouse

Williams, T.D.; Warnock, N.; Takekawa, John Y.; Bishop, M.A.

2007-01-01

We combined radiotelemetry, plasma metabolite analyses, and macro-invertebrate prey sampling to investigate variation in putative fattening rates (estimated as plasma triglyceride levels) at the flyway scale in Western Sandpipers (Calidris mauri) migrating between Punta Banda, Mexico (31°N), and Hartney Bay, Alaska (60°N), a distance of 4,240 km. Birds were caught at a wintering site (San Francisco Bay) and eight stopover sites along this Pacific Flyway. Body mass was higher in females than in males at six sites, but variation was not correlated with latitude for either sex, and the relationship of change in mass by date within sites was uninformative with regard to possible latitudinal variation in fattening rates. At San Francisco Bay, triglyceride levels were higher in the spring than in the winter. Mean plasma triglyceride varied among stopover sites, and there was a significant linear trend of increasing triglyceride levels with latitude as birds migrated north. At San Francisco Bay, length of stay was negatively related to triglyceride levels. However, plasma triglyceride levels at wintering or initial stopover sites (San Francisco and Punta Banda) did not predict individual variation in subsequent rates of travel during migration. We found no significant relationship between triglyceride levels and prey biomass at different stopover sites, which suggests that the latitudinal pattern is not explained by latitudinal changes in food availability. Rather, we suggest that differences in physiology of migratory birds at southern versus northern stopover sites or behavioral differences may allow birds to sustain higher fattening rates closer to the breeding grounds.

Weather conditions promote route flexibility during open ocean crossing in a long-distance migratory raptor

NASA Astrophysics Data System (ADS)

Mellone, Ugo; López-López, Pascual; Limiñana, Rubén; Urios, Vicente

2011-07-01

Weather conditions are paramount in shaping birds' migratory routes, promoting the evolution of behavioural plasticity and allowing for adaptive decisions on when to depart or stop during migration. Here, we describe and analyze the influence of weather conditions in shaping the sea-crossing stage of the pre-breeding journey made by a long-distance migratory bird, the Eleonora's falcon ( Falco eleonorae), tracked by satellite telemetry from the wintering grounds in the Southern Hemisphere to the breeding sites in the Northern Hemisphere. As far as we know, the data presented here are the first report of repeated oceanic journeys of the same individuals in consecutive years. Our results show inter-annual variability in the routes followed by Eleonora's falcons when crossing the Strait of Mozambique, between Madagascar and eastern continental Africa. Interestingly, our observations illustrate that individuals show high behavioural plasticity and are able to change their migration route from one year to another in response to weather conditions, thus minimising the risk of long ocean crossing by selecting winds blowing towards Africa for departure and changing the routes to avoid low pressure areas en route. Our results suggest that weather conditions can really act as obstacles during migration, and thus, besides ecological barriers, the migratory behaviour of birds could also be shaped by "meteorological barriers". We briefly discuss orientation mechanisms used for navigation. Since environmental conditions during migration could cause carry-over effects, we consider that forecasting how global changes of weather patterns will shape the behaviour of migratory birds is of the utmost importance.

Molecular Detection of Hematozoa Infections in Tundra Swans Relative to Migration Patterns and Ecological Conditions at Breeding Grounds

PubMed Central

Ramey, Andrew M.; Ely, Craig R.; Schmutz, Joel A.; Pearce, John M.; Heard, Darryl J.

2012-01-01

Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC). We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska. PMID:23049862

Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds

USGS Publications Warehouse

Ramey, Andrew M.; Ely, Craig R.; Schmutz, Joel A.; Pearce, John M.; Heard, Darryl J.

2012-01-01

Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC). We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska.

Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds.

PubMed

Ramey, Andrew M; Ely, Craig R; Schmutz, Joel A; Pearce, John M; Heard, Darryl J

2012-01-01

Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the prevalence and genetic diversity of parasites. We evaluated whether migratory patterns and environmental conditions at breeding areas explain the prevalence of blood parasites in migratory birds by contrasting the fit of competing models formulated in an occupancy modeling framework and calculating the detection probability of the top model using Akaike Information Criterion (AIC). We described genetic diversity of blood parasites in each population of swans by calculating the number of unique parasite haplotypes observed. Blood parasite infection was significantly different between populations of Alaska tundra swans, with the highest estimated prevalence occurring among birds occupying breeding areas with lower mean daily wind speeds and higher daily summer temperatures. Models including covariates of wind speed and temperature during summer months at breeding grounds better predicted hematozoa prevalence than those that included annual migration distance or duration. Genetic diversity of blood parasites in populations of tundra swans appeared to be relative to hematozoa prevalence. Our results suggest ecological conditions at breeding grounds may explain differences of hematozoa infection among populations of tundra swans that breed in Alaska.

Endogenous timing factors in bird migration

NASA Technical Reports Server (NTRS)

Gwinner, E. G.

1972-01-01

Several species of warbler birds were observed in an effort to determine what initiates and terminates migration. Environmental and endogenous timing mechanisms were analyzed. The results indicate that endogenous stimuli are dominant factors for bird migration especially for long distances. It was concluded that environmental factors act as an assist mechanism.

Detection of tick-borne encephalitis virus in I. ricinus ticks collected from autumn migratory birds in Latvia.

PubMed

Kazarina, Alisa; Japiņa, Kristīne; Keišs, Oskars; Salmane, Ineta; Bandere, Dace; Capligina, Valentina; Ranka, Renāte

2015-03-01

Birds have a potential of spreading ticks via bird migration routes. In this study, we screened 170 ticks removed during autumn 2010 from 55 birds belonging to 10 species for the presence of tick-borne encephalitis virus (TBEV). In total, TBEV RNA was detected in 14% of I. ricinus tick samples obtained from different birds species. The results of this study indicate the possible role of migrating birds in the dispersal of TBEV-infected ticks along the southward migration route. Copyright © 2014 Elsevier GmbH. All rights reserved.

Concealed by darkness: interactions between predatory bats and nocturnally migrating songbirds illuminated by DNA sequencing.

PubMed

Ibáñez, Carlos; Popa-Lisseanu, Ana G; Pastor-Beviá, David; García-Mudarra, Juan L; Juste, Javier

2016-10-01

Recently, several species of aerial-hawking bats have been found to prey on migrating songbirds, but details on this behaviour and its relevance for bird migration are still unclear. We sequenced avian DNA in feather-containing scats of the bird-feeding bat Nyctalus lasiopterus from Spain collected during bird migration seasons. We found very high prey diversity, with 31 bird species from eight families of Passeriformes, almost all of which were nocturnally flying sub-Saharan migrants. Moreover, species using tree hollows or nest boxes in the study area during migration periods were not present in the bats' diet, indicating that birds are solely captured on the wing during night-time passage. Additional to a generalist feeding strategy, we found that bats selected medium-sized bird species, thereby assumingly optimizing their energetic cost-benefit balance and injury risk. Surprisingly, bats preyed upon birds half their own body mass. This shows that the 5% prey to predator body mass ratio traditionally assumed for aerial hunting bats does not apply to this hunting strategy or even underestimates these animals' behavioural and mechanical abilities. Considering the bats' generalist feeding strategy and their large prey size range, we suggest that nocturnal bat predation may have influenced the evolution of bird migration strategies and behaviour. © 2016 John Wiley & Sons Ltd.

Obese super athletes: fat-fueled migration in birds and bats.

PubMed

Guglielmo, Christopher G

2018-03-07

Migratory birds are physiologically specialized to accumulate massive fat stores (up to 50-60% of body mass), and to transport and oxidize fatty acids at very high rates to sustain flight for many hours or days. Target gene, protein and enzyme analyses and recent -omic studies of bird flight muscles confirm that high capacities for fatty acid uptake, cytosolic transport, and oxidation are consistent features that make fat-fueled migration possible. Augmented circulatory transport by lipoproteins is suggested by field data but has not been experimentally verified. Migratory bats have high aerobic capacity and fatty acid oxidation potential; however, endurance flight fueled by adipose-stored fat has not been demonstrated. Patterns of fattening and expression of muscle fatty acid transporters are inconsistent, and bats may partially fuel migratory flight with ingested nutrients. Changes in energy intake, digestive capacity, liver lipid metabolism and body temperature regulation may contribute to migratory fattening. Although control of appetite is similar in birds and mammals, neuroendocrine mechanisms regulating seasonal changes in fuel store set-points in migrants remain poorly understood. Triacylglycerol of birds and bats contains mostly 16 and 18 carbon fatty acids with variable amounts of 18:2n-6 and 18:3n-3 depending on diet. Unsaturation of fat converges near 70% during migration, and unsaturated fatty acids are preferentially mobilized and oxidized, making them good fuel. Twenty and 22 carbon n-3 and n-6 polyunsaturated fatty acids (PUFA) may affect membrane function and peroxisome proliferator-activated receptor signaling. However, evidence for dietary PUFA as doping agents in migratory birds is equivocal and requires further study. © 2018. Published by The Company of Biologists Ltd.

Patterns of seabird and marine mammal carcass deposition along the central California coast, 1980-1986

USGS Publications Warehouse

Bodkin, James L.; Jameson, Ronald J.

1991-01-01

At monthly intervals from February 1980 through December 1986, a 14.5-km section of central California coastline was systematically surveyed for beach-cast carcasses of marine birds and mammals. Five hundred and fifty-four bird carcasses and 194 marine mammal carcasses were found. Common murres, western grebes, and Brandt's cormorants composed 45% of the bird total. California sea lions, sea otters, and harbor seals composed 90% of the mammal total. Several factors appeared to affect patterns of carcass deposition. The El Niño – Southern Oscillation (ENSO) of 1982–1983 was the dominant influence in terms of interannual variation in carcass deposition. During this ENSO, 56% of the seabirds and 48% of the marine mammals washed ashore. Patterns of intra-annual variation were species specific and were related to animal migration patterns, reproduction, and seasonal changes in weather. Nearshore currents and winds influenced the general area of carcass deposition, while beach substrate type and local patterns of sand deposition influenced the location of carcass deposition on a smaller spatial scale. Weekly surveys along a 1.1-km section of coastline indicated that 62% of bird carcasses and 41% of mammal carcasses remained on the beach less than 9 days. Cause of death was determined for only 8% of the carcasses. Oiling was the most common indication of cause of death in birds (6%). Neonates composed 8% of all mammal carcasses.

Patterns of migrating soaring migrants indicate attraction to marine wind farms

PubMed Central

Desholm, Mark; Heinänen, Stefan; Kahlert, Johnny A.; Laubek, Bjarke; Jensen, Niels Einar; Žydelis, Ramūnas; Jensen, Bo Præstegaard

2016-01-01

Monitoring of bird migration at marine wind farms has a short history, and unsurprisingly most studies have focused on the potential for collisions. Risk for population impacts may exist to soaring migrants such as raptors with K-strategic life-history characteristics. Soaring migrants display strong dependence on thermals and updrafts and an affinity to land areas and islands during their migration, a behaviour that creates corridors where raptors move across narrow straits and sounds and are attracted to islands. Several migration corridors for soaring birds overlap with the development regions for marine wind farms in NW Europe. However, no empirical data have yet been available on avoidance or attraction rates and behavioural reactions of soaring migrants to marine wind farms. Based on a post-construction monitoring study, we show that all raptor species displayed a significant attraction behaviour towards a wind farm. The modified migratory behaviour was also significantly different from the behaviour at nearby reference sites. The attraction was inversely related to distance to the wind farm and was primarily recorded during periods of adverse wind conditions. The attraction behaviour suggests that migrating raptor species are far more at risk of colliding with wind turbines at sea than hitherto assessed. PMID:28003522

February precipitation in the wintering grounds of the lesser whitethroat, Sylvia curruca: is it a cue for migration onset?

PubMed

Aloni, Irith; Markman, Shai; Ziv, Yaron

2017-02-01

Numerous studies report shifts in bird migration phenology, presumably owing to global warming. However, most studies focus on migration patterns in the Northern Hemisphere. In this study, we investigated associations between weather conditions in African wintering grounds of the lesser whitethroat, Sylvia curruca, and spring arrival time in Eilat, Israel. Using multivariate regression models, we analysed a 30-year dataset in order to examine correlations between median springtime arrival and 46 climate variables of the wintering quarters. The model obtained exhibited a highly statistical fit, involving mean precipitation in February and March with negative effects and number of wet days during November-February. February precipitation levels were also the major factor associated with the interquartile range of arrival time. Interestingly and contrary to published results, annual or seasonal precipitation showed no correlation with spring arrival time, nor did temperature. Moreover, winter in this region falls into dry season with negligible rainfall quantities. Hence, it is unlikely that precipitation effect on habitat productivity is a driving force of migration, as suggested by other studies. Instead, we propose that precipitation in February acts as a cue for the birds, indicating the approach of spring and migration time.

Light pollution is greatest within migration passage areas for nocturnally-migrating birds around the world.

PubMed

Cabrera-Cruz, Sergio A; Smolinsky, Jaclyn A; Buler, Jeffrey J

2018-02-19

Excessive or misdirected artificial light at night (ALAN) produces light pollution that influences several aspects of the biology and ecology of birds, including disruption of circadian rhythms and disorientation during flight. Many migrating birds traverse large expanses of land twice every year at night when ALAN illuminates the sky. Considering the extensive and increasing encroachment of light pollution around the world, we evaluated the association of the annual mean ALAN intensity over land within the geographic ranges of 298 nocturnally migrating bird species with five factors: phase of annual cycle, mean distance between breeding and non-breeding ranges, range size, global hemisphere of range, and IUCN category of conservation concern. Light pollution within geographic ranges was relatively greater during the migration season, for shorter-distance migrants, for species with smaller ranges, and for species in the western hemisphere. Our results suggest that migratory birds may be subject to the effects of light pollution particularly during migration, the most critical stage in their annual cycle. We hope these results will spur further research on how light pollution affects not only migrating birds, but also other highly mobile animals throughout their annual cycle.

Bat predation on nocturnally migrating birds

PubMed Central

Ibáñez, Carlos; Juste, Javier; García-Mudarra, Juan L.; Agirre-Mendi, Pablo T.

2001-01-01

Bat predation on birds is a very rare phenomenon in nature. Most documented reports of bird-eating bats refer to tropical bats that occasionally capture resting birds. Millions of small birds concentrate and cross over the world's temperate regions during migration, mainly at night, but no nocturnal predators are known to benefit from this enormous food resource. An analysis of 14,000 fecal pellets of the greater noctule bat (Nyctalus lasiopterus) reveals that this species captures and eats large numbers of migrating passerines, making it the only bat species so far known that regularly preys on birds. The echolocation characteristics and wing morphology of this species strongly suggest that it captures birds in flight. PMID:11493689

Radar studies of bird migration

NASA Technical Reports Server (NTRS)

Williams, T. C.; Williams, J. M.

1974-01-01

Observations of bird migration with NASA radars were made at Wallops Island, Va. Simultaneous observations were made at a number of radar sites in the North Atlantic Ocean in an effort to discover what happened to those birds that were observed leaving the coast of North America headed toward Bermuda, the Caribbean and South America. Transatlantic migration, utilizing observations from a large number of radars is discussed. Detailed studies of bird movements at Wallops Island are presented.

Social learning of migratory performance

USGS Publications Warehouse

Mueller, Thomas; O'Hara, Robert B.; Converse, Sarah J.; Urbanek, Richard P.; Fagan, William F.

2013-01-01

Successful bird migration can depend on individual learning, social learning, and innate navigation programs. Using 8 years of data on migrating whooping cranes, we were able to partition genetic and socially learned aspects of migration. Specifically, we analyzed data from a reintroduced population wherein all birds were captive bred and artificially trained by ultralight aircraft on their first lifetime migration. For subsequent migrations, in which birds fly individually or in groups but without ultralight escort, we found evidence of long-term social learning, but no effect of genetic relatedness on migratory performance. Social learning from older birds reduced deviations from a straight-line path, with 7 years of experience yielding a 38% improvement in migratory accuracy.

Detecting mismatches of bird migration stopover and tree phenology in response to changing climate

USGS Publications Warehouse

Kellermann, Jherime L.; van Riper, Charles

2015-01-01

Migratory birds exploit seasonal variation in resources across latitudes, timing migration to coincide with the phenology of food at stopover sites. Differential responses to climate in phenology across trophic levels can result in phenological mismatch; however, detecting mismatch is sensitive to methodology. We examined patterns of migrant abundance and tree flowering, phenological mismatch, and the influence of climate during spring migration from 2009 to 2011 across five habitat types of the Madrean Sky Islands in southeastern Arizona, USA. We used two metrics to assess phenological mismatch: synchrony and overlap. We also examined whether phenological overlap declined with increasing difference in mean event date of phenophases. Migrant abundance and tree flowering generally increased with minimum spring temperature but depended on annual climate by habitat interactions. Migrant abundance was lowest and flowering was highest under cold, snowy conditions in high elevation montane conifer habitat while bird abundance was greatest and flowering was lowest in low elevation riparian habitat under the driest conditions. Phenological synchrony and overlap were unique and complementary metrics and should both be used when assessing mismatch. Overlap declined due to asynchronous phenologies but also due to reduced migrant abundance or flowering when synchrony was actually maintained. Overlap declined with increasing difference in event date and this trend was strongest in riparian areas. Montane habitat specialists may be at greatest risk of mismatch while riparian habitat could provide refugia during dry years for phenotypically plastic species. Interannual climate patterns that we observed match climate change projections for the arid southwest, altering stopover habitat condition.

International migration patterns of Red-throated Loons (Gavia stellata) from four breeding populations in Alaska

USGS Publications Warehouse

McCloskey, Sarah E.; Uher-Koch, Brian D.; Schmutz, Joel A.; Fondell, Thomas F.

2018-01-01

Identifying post-breeding migration and wintering distributions of migratory birds is important for understanding factors that may drive population dynamics. Red-throated Loons (Gavia stellata) are widely distributed across Alaska and currently have varying population trends, including some populations with recent periods of decline. To investigate population differentiation and the location of migration pathways and wintering areas, which may inform population trend patterns, we used satellite transmitters (n = 32) to describe migration patterns of four geographically separate breeding populations of Red-throated Loons in Alaska. On average (± SD) Red-throated Loons underwent long (6,288 ± 1,825 km) fall and spring migrations predominantly along coastlines. The most northern population (Arctic Coastal Plain) migrated westward to East Asia and traveled approximately 2,000 km farther to wintering sites than the three more southerly populations (Seward Peninsula, Yukon-Kuskokwim Delta, and Copper River Delta) which migrated south along the Pacific coast of North America. These migration paths are consistent with the hypothesis that Red-throated Loons from the Arctic Coastal Plain are exposed to contaminants in East Asia. The three more southerly breeding populations demonstrated a chain migration pattern in which the more northerly breeding populations generally wintered in more northerly latitudes. Collectively, the migration paths observed in this study demonstrate that some geographically distinct breeding populations overlap in wintering distribution while others use highly different wintering areas. Red-throated Loon population trends in Alaska may therefore be driven by a wide range of effects throughout the annual cycle.

Bird migration through Middle Rio Grande riparian forests, 1994 to 1997

Treesearch

Michael D. Means; Deborah M. Finch

1999-01-01

Expanding human populations in the middle Rio Grande have increased demands on water, land, and other resources, potentially disrupting bird migration activities. From 1994 to 1997, a total of 26,350 birds of 157 species were banded and studied. Results include species composition, timing of migration, and habitat use. Recommendations for managers are included.

Insights on the thermal impacts of wing colorization of migrating birds on their skin friction drag and the choice of their flight route.

PubMed

Hassanalian, M; Ayed, S Ben; Ali, M; Houde, P; Hocut, C; Abdelkefi, A

2018-02-01

The thermal effects of wing color in flight is investigated in four species of birds with respect to their flight routes, migration time, and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these flight routes, a thermal analysis of the birds' wings is performed during their migration. The surrounding fluxes including the ocean flux and the solar irradiance are considered in an energy balance in order to determine the skin temperature of both sides of the wing. Applying the Blasius solution for heated boundary layers, it is shown that the color configuration of these migrating birds, namely black on the top side of the wings and white on the bottom side of the wings ("countershading"), results in a skin drag reduction, if compared to some other configurations, when both day and night are taken into consideration. This drag reduction can be considered as one of the effective factors for long endurance of these migrating birds. This research can provide the evolutionary perspective behind the colorization of these migrating birds. Copyright © 2018 Elsevier Ltd. All rights reserved.

Atmospheric conditions create freeways, detours and tailbacks for migrating birds.

PubMed

Shamoun-Baranes, Judy; Liechti, Felix; Vansteelant, Wouter M G

2017-07-01

The extraordinary adaptations of birds to contend with atmospheric conditions during their migratory flights have captivated ecologists for decades. During the 21st century technological advances have sparked a revival of research into the influence of weather on migrating birds. Using biologging technology, flight behaviour is measured across entire flyways, weather radar networks quantify large-scale migratory fluxes, citizen scientists gather observations of migrant birds and mechanistic models are used to simulate migration in dynamic aerial environments. In this review, we first introduce the most relevant microscale, mesoscale and synoptic scale atmospheric phenomena from the point of view of a migrating bird. We then provide an overview of the individual responses of migrant birds (when, where and how to fly) in relation to these phenomena. We explore the cumulative impact of individual responses to weather during migration, and the consequences thereof for populations and migratory systems. In general, individual birds seem to have a much more flexible response to weather than previously thought, but we also note similarities in migratory behaviour across taxa. We propose various avenues for future research through which we expect to derive more fundamental insights into the influence of weather on the evolution of migratory behaviour and the life-history, population dynamics and species distributions of migrant birds.

Reactions of migrating birds to lights and aircraft.

PubMed Central

Larkin, R P; Torre-Bueno, J R; Griffin, D R; Walcott, C

1975-01-01

Midair collsions between birds and aircraft pose a hazard for both. While observing migrating birds with a tracking radar, we find that birds often react, by taking evasive maneuvers, at distances of 200-300 m to both searchlight beams and the approach of a small airplane with its landing lights on. Appropriately arranged lights on aircraft should decrease the hazard of collisions with birds. Images PMID:1056007

Do birds of like feather flock together? The use of a novel 13C+D combustion isotope analyzer to track bird migration

NASA Astrophysics Data System (ADS)

Saad, N.

2011-12-01

Information on spring migration routes, geographic linkages among winter, spring, and breeding locations, and potential geographic effects on arrival body condition of a variety of avian species is so far little known. Stable isotope ratios are exquisitely sensitive to the biochemistry of living organisms and the nutrients available to them. Isotope ratios provide detailed knowledge useful in a variety of fields, including birds migration, through a combination of stable-isotope measurements of carbon (13C/12C) and hydrogen (D/H) isotopes of flight feathers and breast feathers of tissues representing different periods of dietary integration and body composition analyses. Associations among specific geographic areas, habitat use, and arrival condition can be elucidated through the measurement of these dual isotopes. We report here on the development of a novel laser spectroscopy based system for the simultaneous analysis of the stable isotope ratios of carbon (13C/12C) and hydrogen (D/H) that is robust, easy-to-use, and is the first stable isotope ratio analysis system to combine the measurement of 13C/12C and D/H in one simple analysis from a bulk organic sample with an application to bird migration. The system comprises a combustion module to convert the organic sample into CO2 and H2O and a Cavity Ring-Down Spectrometer (CRDS) that analyzes the combustion species inside an optical cavity based on the molecular absorption of individual isotopomers. This CRDS uses dual lasers to target the four isotpomers of interest: 12CO2, 13CO2, H2O and HDO. The system delivers a typical precision of 0.1 permil for δ13C and 1.5 permil for δD that parallels that achieved by IRMS, but with an unprecedented simplicity that allows ecologists to leverage the science and elucidate the avian migration patterns.

Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds

USGS Publications Warehouse

Hooijmeijer, Jos C. E. W.; Gill, Robert E.; Mulcahy, Daniel M.; Tibbitts, T. Lee; Kentie, Rosemarie; Gerritsen, Gerrit J.; Bruinzeel, Leo W.; Tijssen, David C.; Harwood, Christopher M.; Piersma, Theunis

2014-01-01

Satellite telemetry has become a common technique to investigate avian life-histories, but whether such tagging will affect fitness is a critical unknown. In this study, we evaluate multi-year effects of implanted transmitters on migratory timing and reproductive performance in shorebirds. Shorebirds increasingly are recognized as good models in ecology and evolution. That many of them are of conservation concern adds to the research responsibilities. In May 2009, we captured 56 female Black-tailed Godwits Limosa limosa limosa during late incubation in The Netherlands. Of these, 15 birds were equipped with 26-g satellite transmitters with a percutaneous antenna (7.8 % ± 0.2 SD of body mass), surgically implanted in the coelom. We compared immediate nest survival, timing of migration, subsequent nest site fidelity and reproductive behaviour including egg laying with those of the remaining birds, a comparison group of 41 females. We found no effects on immediate nest survival. Fledging success and subsequent southward and northward migration patterns of the implanted birds conformed to the expectations, and arrival time on the breeding grounds in 2010–2012 did not differ from the comparison group. Compared with the comparison group, in the year after implantation, implanted birds were equally faithful to the nest site and showed equal territorial behaviour, but a paucity of behaviours indicating nests or clutches. In the 3 years after implantation, the yearly apparent survival of implanted birds was 16 % points lower. Despite intense searching, we found only three eggs of two implanted birds; all were deformed. A similarly deformed egg was reported in a similarly implanted Whimbrel Numenius phaeopus returning to breed in central Alaska. The presence in the body cavity of an object slightly smaller than a normal egg may thus lead to egg malformation and, likely, reduced egg viability. That the use of implanted satellite transmitters in these large shorebirds reduced nesting propensity and might also lead to fertility losses argues against the use of implanted transmitters for studies on breeding biology, and for a careful evaluation of the methodology in studies of migration.

The spring migration of adult North American Ospreys

USGS Publications Warehouse

Martell, Mark S.; Bierregaard, Richard O.; Washburn, Brian E.; Elliott, John E.; Henny, Charles J.; Kennedy, Robert S.; MacLeod, Iain

2014-01-01

Most North American Ospreys (Pandion haliaetus) are migratory, breeding in northern latitudes and migrating long distances to and from their wintering grounds in the tropics. Although fall migration patterns of North American Ospreys have been described and studied, very little has been published about the spring migration of these birds. We used satellite telemetry to: (1) determine the characteristics (timing, duration, migratory routes) of spring migrations of Ospreys; (2) determine if differences in spring migration patterns existed between sexes and among three breeding populations (east coast, midwestern, and western); and (3) compare consecutive fall and spring migrations of individual Ospreys. The median dates for departure from the wintering grounds and arrival on the breeding grounds did not differ significantly between adult male and female Ospreys. Compared to their fall migrations, all male and all east coast Ospreys spent fewer days on migration, fewer days in stopover periods along the migration route, traveled shorter distances overall, and traveled farther (on average) each day during spring. In contrast, fall and spring migration characteristics of all female and western Ospreys were similar. Our findings suggest that, although sex and breeding location might influence the spring migration strategy used by individual Ospreys, both males and females minimize the time spent on migration to ensure a timely arrival on the breeding grounds to establish or defend a nesting territory.

Developing high-resolution spatial data of migration corridors for avian species of concern in regions of high potential wind development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katzner, Todd

2014-06-15

The future of the US economy, our national security, and our environmental quality all depend on decreasing our reliance on foreign oil and on fossil fuels. An essential component of decreasing this reliance is the development of alternative energy sources. Wind power is among the most important alternative energy sources currently available, and the mid-Atlantic region is a primary focus for wind power development. In addition to being important to the development of wind power, the mid-Atlantic region holds a special responsibility for the conservation of the eastern North America's golden eagles (Aquila chrysaetos). This small population breeds in northeasternmore » Canada, winters in the southern Appalachians, and nearly all of these birds pass through the mid-Atlantic region twice each year. Movement of these birds is not random and, particularly during spring and autumn, migrating golden eagles concentrate in a narrow 30-50 mile wide corridor in central Pennsylvania. Thus, because the fate of these rare birds may depend on responsible management of the habitat they use it is critical to use research to identify ways to mitigate prospective impacts on this and similar raptor species. The goal of this project was to develop high-resolution spatial risk maps showing migration corridors of and habitat use by eastern golden eagles in regions of high potential for wind development. To accomplish this, we first expanded existing models of raptor migration for the eastern USA to identify broad-scale migration patterns. We then used data from novel high-resolution tracking devices to discover routes of passage and detailed flight behavior of individual golden eagles throughout the eastern USA. Finally, we integrated these data and models to predict population-level migration patterns and individual eagle flight behavior on migration. We then used this information to build spatially explicit, probabilistic maps showing relative risk to birds from wind development. This project has numerous benefits to people and to wildlife, primarily because it will provide a framework for safer and less controversial development of wind power. Because golden eagles are an important "umbrella" for other raptors, this project benefits a suite of species that may be impacted by wind turbines. Finally this work is a recognized priority for central Appalachian states and it is explicitly called for in, and meets the goals of, numerous state wildlife conservation plans. The final product we created, a region-wide map of relative risk to eagles of development of wind power, has allowed us to make specific recommendations regarding siting and operation of and mitigation at wind facilities. This approach also serves as a model for other projects to protect eagles in other places and to conserve suites of species beyond raptors.« less

Patterns of migrating soaring migrants indicate attraction to marine wind farms.

PubMed

Skov, Henrik; Desholm, Mark; Heinänen, Stefan; Kahlert, Johnny A; Laubek, Bjarke; Jensen, Niels Einar; Žydelis, Ramūnas; Jensen, Bo Præstegaard

2016-12-01

Monitoring of bird migration at marine wind farms has a short history, and unsurprisingly most studies have focused on the potential for collisions. Risk for population impacts may exist to soaring migrants such as raptors with K-strategic life-history characteristics. Soaring migrants display strong dependence on thermals and updrafts and an affinity to land areas and islands during their migration, a behaviour that creates corridors where raptors move across narrow straits and sounds and are attracted to islands. Several migration corridors for soaring birds overlap with the development regions for marine wind farms in NW Europe. However, no empirical data have yet been available on avoidance or attraction rates and behavioural reactions of soaring migrants to marine wind farms. Based on a post-construction monitoring study, we show that all raptor species displayed a significant attraction behaviour towards a wind farm. The modified migratory behaviour was also significantly different from the behaviour at nearby reference sites. The attraction was inversely related to distance to the wind farm and was primarily recorded during periods of adverse wind conditions. The attraction behaviour suggests that migrating raptor species are far more at risk of colliding with wind turbines at sea than hitherto assessed. © 2016 The Author(s).

Arthropods and associated arthropod-borne diseases transmitted by migrating birds. The case of ticks and tick-borne pathogens.

PubMed

Sparagano, Olivier; George, David; Giangaspero, Annunziata; Špitalská, Eva

2015-09-30

Geographic spread of parasites and pathogens poses a constant risk to animal health and welfare, particularly given that climate change is expected to potentially expand appropriate ranges for many key species. The spread of deleterious organisms via trade routes and human travelling is relatively closely controlled, though represents only one possible means of parasite/pathogen distribution. The transmission via natural parasite/pathogen movement between geographic locales, is far harder to manage. Though the extent of such movement may be limited by the relative inability of many parasites and pathogens to actively migrate, passive movement over long distances may still occur via migratory hosts. This paper reviews the potential role of migrating birds in the transfer of ectoparasites and pathogens between geographic locales, focusing primarily on ticks. Bird-tick-pathogen relationships are considered, and evidence provided of long-range parasite/pathogen transfer from one location to another during bird migration events. As shown in this paper not only many different arthropod species are carried by migrating birds but consequently these pests carry many different pathogens species which can be transmitted to the migrating birds or to other animal species when those arthropods are dropping during these migrations. Data available from the literature are provided highlighting the need to understand better dissemination paths and disease epidemiology. Copyright © 2015 Elsevier B.V. All rights reserved.

Conserving migratory land birds in the New World: Do we know enough?

USGS Publications Warehouse

Faaborg, John; Holmes, Richard T.; Anders, A.D.; Bildstein, K.L.; Dugger, K.M.; Gauthreaux, S.A.; Heglund, P.; Hobson, K.A.; Jahn, A.E.; Johnson, D.H.; Latta, S.C.; Levey, D.J.; Marra, P.P.; Merkord, C.L.; Nol, E.; Rothstein, S.I.; Sherry, T.W.; Scott, Sillett T.; Thompson, F. R.; Warnock, N.

2010-01-01

Migratory bird needs must be met during four phases of the year: breeding season, fall migration, wintering, and spring migration; thus, management may be needed during all four phases. The bulk of research and management has focused on the breeding season, although several issues remain unsettled, including the spatial extent of habitat influences on fitness and the importance of habitat on the breeding grounds used after breeding. Although detailed investigations have shed light on the ecology and population dynamics of a few avian species, knowledge is sketchy for most species. Replication of comprehensive studies is needed for multiple species across a range of areas. Information deficiencies are even greater during the wintering season, when birds require sites that provide security and food resources needed for survival and developing nutrient reserves for spring migration and, possibly, reproduction. Research is needed on many species simply to identify geographic distributions, wintering sites, habitat use, and basic ecology. Studies are complicated, however, by the mobility of birds and by sexual segregation during winter. Stable-isotope methodology has offered an opportunity to identify linkages between breeding and wintering sites, which facilitates understanding the complete annual cycle of birds. The twice-annual migrations are the poorest-understood events in a bird's life. Migration has always been a risky undertaking, with such anthropogenic features as tall buildings, towers, and wind generators adding to the risk, Species such as woodland specialists migrating through eastern North America have numerous options for pausing during migration to replenish nutrients, but some species depend on limited stopover locations. Research needs for migration include identifying pathways and timetables of migration, quality and distribution of habitats, threats posed by towers and other tall structures, and any bottlenecks for migration. Issues such as human population growth, acid deposition, climate change, and exotic diseases are global concerns with uncertain consequences to migratory birds and even lesscertain remedies. Despite enormous gaps in our understanding of these birds, research, much of it occurring in the past 30 years, has provided sufficient information to make intelligent conservation efforts but needs to expand to handle future challenges. ?? 2010 by the Ecological Society of America.

Conserving migratory land birds in the new world: do we know enough?

PubMed

Faaborg, John; Holmes, Richard T; Anders, Angela D; Bildstein, Keith L; Dugger, Katie M; Gauthreaux, Sidney A; Heglund, Patricia; Hobson, Keith A; Jahn, Alex E; Johnson, Douglas H; Latta, Steven C; Levey, Douglas J; Marra, Peter P; Merkord, Christopher L; Nol, Erica; Rothstein, Stephen I; Sherry, Thomas W; Sillett, T Scott; Thompson, Frank R; Warnock, Nils

2010-03-01

Migratory bird needs must be met during four phases of the year: breeding season, fall migration, wintering, and spring migration; thus, management may be needed during all four phases. The bulk of research and management has focused on the breeding season, although several issues remain unsettled, including the spatial extent of habitat influences on fitness and the importance of habitat on the breeding grounds used after breeding. Although detailed investigations have shed light on the ecology and population dynamics of a few avian species, knowledge is sketchy for most species. Replication of comprehensive studies is needed for multiple species across a range of areas, Information deficiencies are even greater during the wintering season, when birds require sites that provide security and food resources needed for survival and developing nutrient reserves for spring migration and, possibly, reproduction. Research is needed on many species simply to identify geographic distributions, wintering sites, habitat use, and basic ecology. Studies are complicated, however, by the mobility of birds and by sexual segregation during winter. Stable-isotope methodology has offered an opportunity to identify linkages between breeding and wintering sites, which facilitates understanding the complete annual cycle of birds. The twice-annual migrations are the poorest-understood events in a bird's life. Migration has always been a risky undertaking, with such anthropogenic features as tall buildings, towers, and wind generators adding to the risk. Species such as woodland specialists migrating through eastern North America have numerous options for pausing during migration to replenish nutrients, but some species depend on limited stopover locations. Research needs for migration include identifying pathways and timetables of migration, quality and distribution of habitats, threats posed by towers and other tall structures, and any bottlenecks for migration. Issues such as human population growth, acid deposition, climate change, and exotic diseases are global concerns with uncertain consequences to migratory birds and even less-certain remedies. Despite enormous gaps in our understanding of these birds, research, much of it occurring in the past 30 years, has provided sufficient information to make intelligent conservation efforts but needs to expand to handle future challenges.

Calibration of magnetic and celestial compass cues in migratory birds--a review of cue-conflict experiments.

PubMed

Muheim, Rachel; Moore, Frank R; Phillips, John B

2006-01-01

Migratory birds use multiple sources of compass information for orientation, including the geomagnetic field, the sun, skylight polarization patterns and star patterns. In this paper we review the results of cue-conflict experiments designed to determine the relative importance of the different compass mechanisms, and how directional information from these compass mechanisms is integrated. We focus on cue-conflict experiments in which the magnetic field was shifted in alignment relative to natural celestial cues. Consistent with the conclusions of earlier authors, our analyses suggest that during the premigratory season, celestial information is given the greatest salience and used to recalibrate the magnetic compass by both juvenile and adult birds. Sunset polarized light patterns from the region of the sky near the horizon appear to provide the calibration reference for the magnetic compass. In contrast, during migration, a majority of experiments suggest that birds rely on the magnetic field as the primary source of compass information and use it to calibrate celestial compass cues, i.e. the relative saliency of magnetic and celestial cues is reversed. An alternative possibility, however, is suggested by several experiments in which birds exposed to a cue conflict during migration appear to have recalibrated the magnetic compass, i.e. their response is similar to that of birds exposed to cue conflicts during the premigratory season. The general pattern to emerge from these analyses is that birds exposed to the cue conflict with a view of the entire sunset sky tended to recalibrate the magnetic compass, regardless of whether the cue conflict occurred during the premigratory or migratory period. In contrast, birds exposed to the cue conflict in orientation funnels and registration cages that restricted their view of the region of sky near the horizon (as was generally the case in experiments carried out during the migratory season) did not recalibrate the magnetic compass but, instead, used the magnetic compass to calibrate the other celestial compass systems. If access to critical celestial cues, rather than the timing of exposure to the cue conflict (i.e. premigratory vs migratory), determines whether recalibration of the magnetic compass occurs, this suggests that under natural conditions there may be a single calibration reference for all of the compass systems of migratory birds that is derived from sunset (and possibly also sunrise) polarized light cues from the region of sky near the horizon. In cue-conflict experiments carried out during the migratory season, there was also an interesting asymmetry in the birds' response to magnetic fields shifted clockwise and counterclockwise relative to celestial cues. We discuss two possible explanations for these differences: (1) lateral asymmetry in the role of the right and left eye in mediating light-dependent magnetic compass orientation and (2) interference from the spectral and intensity distribution of skylight at sunset with the response of the light-dependent magnetic compass.

Spring bird migration in Mississippi Alluvial Valley forests

USGS Publications Warehouse

Wilson, R. Randy; Twedt, Daniel J.

2003-01-01

We surveyed forest songbirds during migration in bottomland hardwood forest stands and managed cottonwood (Populus deltoides) plantations in northeast Louisiana and west-central Mississippi between 24 March and 24 May 1996 and 1997. We detected more bird species in bottomland hardwood stands than in cottonwood stands. Within hardwood stands, we detected more individuals in stands subjected to uneven-aged timber harvest than in unmanaged stands. Early in migration, avian species composition was similar in both forest types, being comprised mainly of short-distance migrants. Bird species composition in these forest types became increasingly disparate as long-distance neotropical-nearctic migrants arrived. Ten bird species were characteristic of bottomland hardwood forests, whereas eight different species were characteristic of managed cottonwood plantations. Because these two forest types supported different bird communities, both forest types provide important inland stopover habitat during migration. Silvicultural management of bottomland hardwood forests that increases their understory vegetation will provide forested habitat for a more species rich and abundant population of songbirds during migration.

Influenza A virus evolution and spatio-temporal dynamics in Eurasian wild birds: a phylogenetic and phylogeographical study of whole-genome sequence data

PubMed Central

Lewis, Nicola S.; Verhagen, Josanne H.; Javakhishvili, Zurab; Russell, Colin A.; Lexmond, Pascal; Westgeest, Kim B.; Bestebroer, Theo M.; Halpin, Rebecca A.; Lin, Xudong; Ransier, Amy; Fedorova, Nadia B.; Stockwell, Timothy B.; Latorre-Margalef, Neus; Olsen, Björn; Smith, Gavin; Bahl, Justin; Wentworth, David E.; Waldenström, Jonas; Fouchier, Ron A. M.

2015-01-01

Low pathogenic avian influenza A viruses (IAVs) have a natural host reservoir in wild waterbirds and the potential to spread to other host species. Here, we investigated the evolutionary, spatial and temporal dynamics of avian IAVs in Eurasian wild birds. We used whole-genome sequences collected as part of an intensive long-term Eurasian wild bird surveillance study, and combined this genetic data with temporal and spatial information to explore the virus evolutionary dynamics. Frequent reassortment and co-circulating lineages were observed for all eight genomic RNA segments over time. There was no apparent species-specific effect on the diversity of the avian IAVs. There was a spatial and temporal relationship between the Eurasian sequences and significant viral migration of avian IAVs from West Eurasia towards Central Eurasia. The observed viral migration patterns differed between segments. Furthermore, we discuss the challenges faced when analysing these surveillance and sequence data, and the caveats to be borne in mind when drawing conclusions from the apparent results of such analyses. PMID:25904147

Arctic shorebirds in North America: A decade of monitoring

USGS Publications Warehouse

Bart, Jonathan R.; Johnston, Victoria H.

2012-01-01

Each year shorebirds from North and South America migrate thousands of miles to spend the summer in the Arctic. There they feed in shoreline marshes and estuaries along some of the most productive and pristine coasts anywhere. With so much available food they are able to reproduce almost explosively; and as winter approaches, they retreat south along with their offspring, to return to the Arctic the following spring. This remarkable pattern of movement and activity has been the object of intensive study by an international team of ornithologists who have spent a decade counting, surveying, and observing these shorebirds. In this important synthetic work, they address multiple questions about these migratory bird populations. How many birds occupy Arctic ecosystems each summer? How long do visiting shorebirds linger before heading south? How fecund are these birds? Where exactly do they migrate and where exactly do they return? Are their populations growing or shrinking? The results of this study are crucial for better understanding how environmental policies will influence Arctic habitats as well as the far-ranging winter habitats used by migratory shorebirds.

Differential autumn migration of the aquatic warbler Acrocephalus paludicola

NASA Astrophysics Data System (ADS)

Wojczulanis-Jakubas, Katarzyna; Jakubas, Dariusz; Foucher, Julien; Dziarska-Pałac, Joanna; Dugué, Hubert

2013-11-01

Relatively little attention has been paid to sex differences in the migration of birds in autumn. We studied the autumn migration strategy of molecularly sexed males and females in the globally threatened aquatic warbler Acrocephalus paludicola. We captured 176 birds at a stopover site in the Loire estuary at Donges, France. The median date for the passage of adults was 8 days earlier in males than females, although the timing of migration in first-year males and females was similar. This indicates that males, who are without parental duties, can start their migration earlier than females and first-year birds. Adults were significantly heavier than immature birds but did not have higher fat scores. In both age categories, more males (two to three times more) were captured. However, various factors (including tape-luring) can affect observed sex ratio.

Seasonal effects of wind conditions on migration patterns of soaring American white pelican.

PubMed

Gutierrez Illan, Javier; Wang, Guiming; Cunningham, Fred L; King, D Tommy

2017-01-01

Energy and time expenditures are determinants of bird migration strategies. Soaring birds have developed migration strategies to minimize these costs, optimizing the use of all the available resources to facilitate their displacement. We analysed the effects of different wind factors (tailwind, turbulence, vertical updrafts) on the migratory flying strategies adopted by 24 satellite-tracked American white pelicans (Pelecanus erythrorhynchos) throughout spring and autumn in North America. We hypothesize that different wind conditions encountered along migration routes between spring and autumn induce pelicans to adopt different flying strategies and use of these wind resources. Using quantile regression and fine-scale atmospheric data, we found that the pelicans optimized the use of available wind resources, flying faster and more direct routes in spring than in autumn. They actively selected tailwinds in both spring and autumn displacements but relied on available updrafts predominantly in their spring migration, when they needed to arrive at the breeding regions. These effects varied depending on the flying speed of the pelicans. We found significant directional correlations between the pelican migration flights and wind direction. In light of our results, we suggest plasticity of migratory flight strategies by pelicans is likely to enhance their ability to cope with the effects of ongoing climate change and the alteration of wind regimes. Here, we also demonstrate the usefulness and applicability of quantile regression techniques to investigate complex ecological processes such as variable effects of atmospheric conditions on soaring migration.

Seasonal effects of wind conditions on migration patterns of soaring American white pelican

PubMed Central

Wang, Guiming; Cunningham, Fred L.; King, D. Tommy

2017-01-01

Energy and time expenditures are determinants of bird migration strategies. Soaring birds have developed migration strategies to minimize these costs, optimizing the use of all the available resources to facilitate their displacement. We analysed the effects of different wind factors (tailwind, turbulence, vertical updrafts) on the migratory flying strategies adopted by 24 satellite-tracked American white pelicans (Pelecanus erythrorhynchos) throughout spring and autumn in North America. We hypothesize that different wind conditions encountered along migration routes between spring and autumn induce pelicans to adopt different flying strategies and use of these wind resources. Using quantile regression and fine-scale atmospheric data, we found that the pelicans optimized the use of available wind resources, flying faster and more direct routes in spring than in autumn. They actively selected tailwinds in both spring and autumn displacements but relied on available updrafts predominantly in their spring migration, when they needed to arrive at the breeding regions. These effects varied depending on the flying speed of the pelicans. We found significant directional correlations between the pelican migration flights and wind direction. In light of our results, we suggest plasticity of migratory flight strategies by pelicans is likely to enhance their ability to cope with the effects of ongoing climate change and the alteration of wind regimes. Here, we also demonstrate the usefulness and applicability of quantile regression techniques to investigate complex ecological processes such as variable effects of atmospheric conditions on soaring migration. PMID:29065188

Towards the Automatic Classification of Avian Flight Calls for Bioacoustic Monitoring

PubMed Central

Bello, Juan Pablo; Farnsworth, Andrew; Robbins, Matt; Keen, Sara; Klinck, Holger; Kelling, Steve

2016-01-01

Automatic classification of animal vocalizations has great potential to enhance the monitoring of species movements and behaviors. This is particularly true for monitoring nocturnal bird migration, where automated classification of migrants’ flight calls could yield new biological insights and conservation applications for birds that vocalize during migration. In this paper we investigate the automatic classification of bird species from flight calls, and in particular the relationship between two different problem formulations commonly found in the literature: classifying a short clip containing one of a fixed set of known species (N-class problem) and the continuous monitoring problem, the latter of which is relevant to migration monitoring. We implemented a state-of-the-art audio classification model based on unsupervised feature learning and evaluated it on three novel datasets, one for studying the N-class problem including over 5000 flight calls from 43 different species, and two realistic datasets for studying the monitoring scenario comprising hundreds of thousands of audio clips that were compiled by means of remote acoustic sensors deployed in the field during two migration seasons. We show that the model achieves high accuracy when classifying a clip to one of N known species, even for a large number of species. In contrast, the model does not perform as well in the continuous monitoring case. Through a detailed error analysis (that included full expert review of false positives and negatives) we show the model is confounded by varying background noise conditions and previously unseen vocalizations. We also show that the model needs to be parameterized and benchmarked differently for the continuous monitoring scenario. Finally, we show that despite the reduced performance, given the right conditions the model can still characterize the migration pattern of a specific species. The paper concludes with directions for future research. PMID:27880836

Bats on a Budget: Torpor-Assisted Migration Saves Time and Energy

PubMed Central

McGuire, Liam P.; Jonasson, Kristin A.; Guglielmo, Christopher G.

2014-01-01

Bats and birds must balance time and energy budgets during migration. Migrating bats face similar physiological challenges to birds, but nocturnality creates special challenges for bats, such as a conflict between travelling and refueling, which many birds avoid by feeding in daylight and flying at night. As endothermic animals, bats and birds alike must expend substantial amounts of energy to maintain high body temperatures. For migratory birds refueling at stopovers, remaining euthermic during inactive periods reduces the net refuelling rate, thereby prolonging stopover duration and delaying subsequent movement. We hypothesized that bats could mitigate similar ambient-temperature dependent costs by using a torpor-assisted migration strategy. We studied silver-haired bats Lasionycteris noctivagans during autumn migration using a combination of respirometry and temperature-sensitive radiotelemetry to estimate energy costs incurred under ambient temperature conditions, and the energy that bats saved by using torpor during daytime roosting periods. All bats, regardless of sex, age, or body condition used torpor at stopover and saved up to 91% of the energy they would have expended to remain euthermic. Furthermore, bats modulated use of torpor depending on ambient temperature. By adjusting the time spent torpid, bats achieved a rate of energy expenditure independent of the ambient temperature encountered at stopover. By lowering body temperature during inactive periods, fuel stores are spared, reducing the need for refuelling. Optimal migration models consider trade-offs between time and energy. Heterothermy provides a physiological strategy that allows bats to conserve energy without paying a time penalty as they migrate. Although uncommon, some avian lineages are known to use heterothermy, and current theoretical models of migration may not be appropriate for these groups. We propose that thermoregulatory strategies should be an important consideration of future migration studies of both bats and birds. PMID:25551615

Climate change and timing of avian breeding and migration: evolutionary versus plastic changes

PubMed Central

Charmantier, Anne; Gienapp, Phillip

2014-01-01

There are multiple observations around the globe showing that in many avian species, both the timing of migration and breeding have advanced, due to warmer springs. Here, we review the literature to disentangle the actions of evolutionary changes in response to selection induced by climate change versus changes due to individual plasticity, that is, the capacity of an individual to adjust its phenology to environmental variables. Within the abundant literature on climate change effects on bird phenology, only a small fraction of studies are based on individual data, yet individual data are required to quantify the relative importance of plastic versus evolutionary responses. While plasticity seems common and often adaptive, no study so far has provided direct evidence for an evolutionary response of bird phenology to current climate change. This assessment leads us to notice the alarming lack of tests for microevolutionary changes in bird phenology in response to climate change, in contrast with the abundant claims on this issue. In short, at present we cannot draw reliable conclusions on the processes underlying the observed patterns of advanced phenology in birds. Rapid improvements in techniques for gathering and analysing individual data offer exciting possibilities that should encourage research activity to fill this knowledge gap. PMID:24454545

Intercontinental spread of asian-origin H5N8 to North America through Beringia by migratory birds

USGS Publications Warehouse

Lee, Dong-Hun; Kim Torchetti, Mia; Winker, Kevin; Ip, Hon S.; Swayne, David E.; Song, Chang-Seon

2015-01-01

Phylogenetic network analysis and understanding of waterfowl migration patterns suggest the Eurasian H5N8 clade 2.3.4.4 avian influenza virus emerged in late 2013 in China, spread in early 2014 to South Korea and Japan, and reached Siberia and Beringia by summer 2014 via migratory birds. Three genetically distinct subgroups emerged and subsequently spread along different flyways during fall 2014 into Europe, North America, and East Asia, respectively. All three subgroups reappeared in Japan, a wintering site for waterfowl from Eurasia and parts of North America.

Influence of Riparian Tree Phenology on Lower Colorado River Spring-Migrating Birds: Implications of Flower Cueing

USGS Publications Warehouse

McGrath, Laura J.; van Riper, Charles

2005-01-01

Executive Summary Neotropical migrant birds make choices about which habitats are most likely to provide successful foraging locations during migration, but little is known about how these birds recognize and process environmental clues that indicate the presence of prey species. Aspects of tree phenology, notably flowering of trees along the lower Colorado River corridor, coincide with the migratory stopovers of leaf-gleaning insectivorous songbirds and may be an important indicator of arthropod prey species availability. Shifting tree flowering and leaf flush during the spring migration period presents avian insectivores with an assortment of foraging opportunities. During two field seasons at Cibola National Wildlife Refuge in southwestern Arizona, we examined riparian tree species to test whether leaf-gleaning insectivorous birds are attracted to the flowering condition of trees in choosing foraging sites. We predicted that flowering trees would host more insect prey resources, would thus show increased visit rates, length of stays and attack ratios of migrant avian insectivores, and that those arthropods would be found in the stomach contents of the birds. Paired trees of honey mesquite (Prosopis glandulosa), displaying heavy and light degrees of flowering were observed to test these predictions. To test whether birds are tracking arthropods directly or are using flowers as a proximate cue, we removed flowers from selected trees and paired these treated trees with neighboring high flowering trees, which served as controls. Avian foraging behavior, avian diets, arthropods, and phenology data were collected at the same time to control for temporal differences in insect availability, plant phenology, and differences in stopover arrivals of birds. We documented five patterns from this study: 1) Higher abundance and richness of arthropods were found on honey mesquite trees with greater numbers of flowers. 2) Arthropod abundance and richness increased as flowering level increased. 3) The subset of migrant avian insectivores selected for study disproportionately foraged among honey mesquite trees with significantly greater amounts of flower coverage than they did on trees with less than average flower coverage. 4) Paired field experiments demonstrated that migrant avian insectivores more often visited, stayed longer, and had higher attack rates on insect prey in honey mesquite trees with greater numbers of flowers. 5) Diet analyses of selected avian insectivores showed over half of their diet consisted of prey significantly associated with honey mesquite flowering. Combined, these results suggest that honey mesquite flowering condition is an important cue used by avian insectivores that enables birds to quickly find arthropod prey at stop-over locations, while in transit during spring migration.

Migration in the Anthropocene: how collective navigation, environmental system and taxonomy shape the vulnerability of migratory species.

PubMed

Hardesty-Moore, Molly; Deinet, Stefanie; Freeman, Robin; Titcomb, Georgia C; Dillon, Erin M; Stears, Keenan; Klope, Maggie; Bui, An; Orr, Devyn; Young, Hillary S; Miller-Ter Kuile, Ana; Hughey, Lacey F; McCauley, Douglas J

2018-05-19

Recent increases in human disturbance pose significant threats to migratory species using collective movement strategies. Key threats to migrants may differ depending on behavioural traits (e.g. collective navigation), taxonomy and the environmental system (i.e. freshwater, marine or terrestrial) associated with migration. We quantitatively assess how collective navigation, taxonomic membership and environmental system impact species' vulnerability by (i) evaluating population change in migratory and non-migratory bird, mammal and fish species using the Living Planet Database (LPD), (ii) analysing the role of collective navigation and environmental system on migrant extinction risk using International Union for Conservation of Nature (IUCN) classifications and (iii) compiling literature on geographical range change of migratory species. Likelihood of population decrease differed by taxonomic group: migratory birds were more likely to experience annual declines than non-migrants, while mammals displayed the opposite pattern. Within migratory species in IUCN, we observed that collective navigation and environmental system were important predictors of extinction risk for fishes and birds, but not for mammals, which had overall higher extinction risk than other taxa. We found high phylogenetic relatedness among collectively navigating species, which could have obscured its importance in determining extinction risk. Overall, outputs from these analyses can help guide strategic interventions to conserve the most vulnerable migrations.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

Plumage quality mediates a life-history trade-off in a migratory bird.

PubMed

Podlaszczuk, Patrycja; Kamiński, Maciej; Włodarczyk, Radosław; Kaczmarek, Krzysztof; Janiszewski, Tomasz; Minias, Piotr

2016-01-01

Moult is one of the most costly activities in the annual cycle of birds and most avian species separate moult from other energy-demanding activities, such as migration. To this end, young birds tend to undergo the first post-juvenile moult before the onset of migration, but in some species the time window for the pre-migratory feather replacement is too narrow. We hypothesized that in such species an increased investment in the structural quality of juvenile feathers may allow to retain juvenile plumage throughout the entire migratory period and delay moult until arriving at wintering grounds, thus avoiding a moult-migration overlap. The effect of juvenile plumage quality on the occurrence of moult-migration overlap was studied in a migratory shorebird, the common snipe Gallinago gallinago . Ca. 400 of first-year common snipe were captured during their final stage of autumn migration through Central Europe. The quality of juvenile feathers was assessed as the mass-length residuals of retained juvenile rectrices. Condition of migrating birds was assessed with the mass of accumulated fat reserves and whole-blood hemoglobin concentration. Path analysis was used to disentangle complex interrelationships between plumage quality, moult and body condition. Snipe which grew higher-quality feathers in the pre-fledging period were less likely to initiate moult during migration. Individuals moulting during migration had lower fat loads and hemoglobin concentrations compared to non-moulting birds, suggesting a trade-off in resource allocation, where energetic costs of moult reduced both energy reserves available for migration and resources available for maintenance of high oxygen capacity of blood. The results of this study indicate that a major life-history trade-off in a migratory bird may be mediated by the quality of juvenile plumage. This is consistent with a silver spoon effect, where early-life investment in feather quality affects future performance of birds during migration period. Our results strongly suggest that the juvenile plumage, although retained for a relatively short period of time, may have profound consequences for individuals' fitness.

Molt patterns and weight changes of the American woodcock

USGS Publications Warehouse

Owen, R.B.; Krohn, W.B.

1973-01-01

A study of molt and changes in body weight of American Woodcock was conducted to better understand the summer and fall behavior of these birds and to indicate periods of physiological stress. The postnuptial molt of adults was a complete molt beginning in late June and ending by the middle of October. In contrast, the postjuvenal molt was a less intensive partial molt beginning in mid-July but also extending to the middle of October. Both male and female adult birds experienced weight loss in August during peak molt. Young birds gradually gained weight throughout the summer. Fat deposition was negatively correlated with molt while fall body weights were positively correlated with fat deposition. The data indicated that the majority of Maine woodcock are not physiologically prepared for migration until mid-October. Weights of adult males during the spring suggested that this is an important period of stress for these birds.

Seasonal influences on sleep and executive function in the migratory White-crowned Sparrow (Zonotrichia leucophrys gambelii)

PubMed Central

2010-01-01

Background We have previously shown that the White-crowned Sparrow (WCS) decreases sleep by 60% during a period of migratory restlessness relative to a non-migratory period when housed in a 12 h light: 12 h dark cycle. Despite this sleep reduction, accuracy of operant performance was not impaired, and in fact rates of responding were elevated during the migratory period, effects opposite to those routinely observed following enforced sleep deprivation. To determine whether the previously observed increases in operant responding were due to improved performance or to the effects of migration on activity level, here we assessed operant performance using a task in which optimal performance depends on the bird's ability to withhold a response for a fixed interval of time (differential-reinforcement-of-low-rate-behavior, or DRL); elevated response rates ultimately impair performance by decreasing access to food reward. To determine the influence of seasonal changes in day length on sleep and behavioral patterns, we recorded sleep and assessed operant performance across 4 distinct seasons (winter, spring, summer and fall) under a changing photoperiod. Results Sleep amount changed in response to photoperiod in winter and summer, with longest sleep duration in the winter. Sleep duration in the spring and fall migratory periods were similar to what we previously reported, and were comparable to sleep duration observed in summer. The most striking difference in sleep during the migratory periods compared to non-migratory periods was the change from discrete day-night temporal organization to an almost complete temporal fragmentation of sleep. The birds' ability to perform on the DRL task was significantly impaired during both migratory periods, but optimal performance was sustained during the two non-migratory periods. Conclusions Birds showed dramatic changes in sleep duration across seasons, related to day length and migratory status. Migration was associated with changes in sleep amount and diurnal distribution pattern, whereas duration of sleep in the non-migratory periods was largely influenced by the light-dark cycle. Elevated response rates on the DRL task were observed during migration but not during the short sleep duration of summer, suggesting that the migratory periods may be associated with decreased inhibition/increased impulsivity. Although their daily sleep amounts and patterns may vary by season, birds are susceptible to sleep loss throughout the year, as evidenced by decreased responding rates following enforced sleep deprivation. PMID:20670404

Migrating songbirds tested in computer-controlled Emlen funnels use stellar cues for a time-independent compass.

PubMed

Mouritsen, H; Larsen, O N

2001-11-01

This paper investigates how young pied flycatchers, Ficedula hypoleuca, and blackcaps, Sylvia atricapilla, interpret and use celestial cues. In order to record these data, we developed a computer-controlled version of the Emlen funnel, which enabled us to make detailed temporal analyses. First, we showed that the birds use a star compass. Then, we tested the birds under a stationary planetarium sky, which simulated the star pattern of the local sky at 02:35 h for 11 consecutive hours of the night, and compared the birds' directional choices as a function of time with the predictions from five alternative stellar orientation hypotheses. The results supported the hypothesis suggesting that birds use a time-independent star compass based on learned geometrical star configurations to pinpoint the rotational point of the starry sky (north). In contrast, neither hypotheses suggesting that birds use the stars for establishing their global position and then perform true star navigation nor those suggesting the use of a time-compensated star compass were supported.

The physiological basis of bird flight

PubMed Central

Butler, Patrick J.

2016-01-01

Flapping flight is energetically more costly than running, although it is less costly to fly a given body mass a given distance per unit time than it is for a similar mass to run the same distance per unit time. This is mainly because birds can fly faster than they can run. Oxygen transfer and transport are enhanced in migrating birds compared with those in non-migrators: at the gas-exchange regions of the lungs the effective area is greater and the diffusion distance smaller. Also, migrating birds have larger hearts and haemoglobin concentrations in the blood, and capillary density in the flight muscles tends to be higher. Species like bar-headed geese migrate at high altitudes, where the availability of oxygen is reduced and the energy cost of flapping flight increased compared with those at sea level. Physiological adaptations to these conditions include haemoglobin with a higher affinity for oxygen than that in lowland birds, a greater effective ventilation of the gas-exchange surface of the lungs and a greater capillary-to-muscle fibre ratio. Migrating birds use fatty acids as their source of energy, so they have to be transported at a sufficient rate to meet the high demand. Since fatty acids are insoluble in water, birds maintain high concentrations of fatty acid–binding proteins to transport fatty acids across the cell membrane and within the cytoplasm. The concentrations of these proteins, together with that of a key enzyme in the β-oxidation of fatty acids, increase before migration. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528774

DEVELOPING AND IMPLEMENTING A BIRD MIGRATION MONITORING, ASSESSMENT AND PUBLIC OUTREACH PROGRAM FOR YOUR COMMUNITY - THE BIRDCAST PROJECT

EPA Science Inventory

The USEPA has developed a technology transfer handbook for the EMPACt BirdCast bird migration monitoring project. The document is essentially a "How-To" Handbook that addresses the planning and implementation steps that were needed to develop, operate and maintain a program simil...

Avian influenza virus wild bird surveillance in the Azov and Black Sea regions of Ukraine

USDA-ARS?s Scientific Manuscript database

The Azov and Black Sea basins are transcontinental migration routes of wild birds from Northern Asia and Europe to the Mediterranean, Africa and Southwest Asia. These regions constitute an area of transit, stops during migration, and nesting of many migratory bird species with a very high level of ...

Avian influenza virus wild bird surveillance in the Azov and Black Sea regions of Ukraine (2010-2011)

USDA-ARS?s Scientific Manuscript database

The Azov and Black Sea basins are part of the transcontinental wild bird migration routes from Northern Asia and Europe to the Mediterranean, Africa and Southwest Asia. These regions constitute an area of transit, stops during migration, and nesting for many different bird species. From September ...

Migratory Birds. Issue Pac.

ERIC Educational Resources Information Center

Fish and Wildlife Service (Dept. of Interior), Washington, DC.

The materials in this educational packet are designed for use with students in grades 4 through 7. They consist of an overview, teaching guides and student data sheets for three activities, and a poster. The overview discusses why, how, where, and when birds migrate as well as problems birds encounter while migrating; the importance of research…

Nocturnal bird migration in opaque clouds

NASA Technical Reports Server (NTRS)

Griffin, D. R.

1972-01-01

The use of a tracking radar to measure the flight paths of migrating birds on nights with opaque clouds is discussed. The effects of wind and lack of visual references are examined. The limitations of the radar observations are described, and samples of tracks obtained during radar observations are included. It is concluded that nonvisual mechanisms of orientation make it possible for birds to migrate in opaque clouds, but the exact nature of the sensory information cannot be determined by radar observations.

Understanding the migratory orientation program of birds: extending laboratory studies to study free-flying migrants in a natural setting.

PubMed

Thorup, Kasper; Holland, Richard A; Tøttrup, Anders P; Wikelski, Martin

2010-09-01

For many years, orientation in migratory birds has primarily been studied in the laboratory. Although a laboratory-based setting enables greater control over environmental cues, the laboratory-based findings must be confirmed in the wild in free-flying birds to be able to fully understand how birds orient during migration. Despite the difficulties associated with following free-flying birds over long distances, a number of possibilities currently exist for tracking the long distance, sometimes even globe-spanning, journeys undertaken by migrating birds. Birds fitted with radio transmitters can either be located from the ground or from aircraft (conventional tracking), or from space. Alternatively, positional information obtained by onboard equipment (e.g., GPS units) can be transmitted to receivers in space. Use of these tracking methods has provided a wealth of information on migratory behaviors that are otherwise very difficult to study. Here, we focus on the progress in understanding certain components of the migration-orientation system. Comparably exciting results can be expected in the future from tracking free-flying migrants in the wild. Use of orientation cues has been studied in migrating raptors (satellite telemetry) and thrushes (conventional telemetry), highlighting that findings in the natural setting may not always be as expected on the basis of cage-experiments. Furthermore, field tracking methods combined with experimental approaches have finally allowed for an extension of the paradigmatic displacement experiments performed by Perdeck in 1958 on the short-distance, social migrant, the starling, to long-distance migrating storks and long-distance, non-socially migrating passerines. Results from these studies provide fundamental insights into the nature of the migratory orientation system that enables experienced birds to navigate and guide inexperienced, young birds to their species-specific winter grounds. © The Author 2010. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

Tornadic storm avoidance behavior in breeding songbirds

USGS Publications Warehouse

Streby, Henry M.; Kramer, Gunnar R.; Peterson, Sean M.; Lehman, Justin A.; Buehler, David A.; Andersen, David E.

2015-01-01

Migration is a common behavior used by animals of many taxa to occupy different habitats during different periods. Migrant birds are categorized as either facultative (i.e., those that are forced to migrate by some proximal cue, often weather) or obligate (i.e., those that migrate on a regular cycle). During migration, obligate migrants can curtail or delay flights in response to inclement weather or until favorable winds prevail, and they can temporarily reorient or reverse direction when ecological or meteorological obstacles are encountered. However, it is not known whether obligate migrants undertake facultative migrations and make large-scale movements in response to proximal cues outside of their regular migration periods. Here, we present the first documentation of obligate long-distance migrant birds undertaking a facultative migration, wherein breeding golden-winged warblers (Vermivora chrysoptera) carrying light-level geolocators performed a >1,500 km 5-day circumvention of a severe tornadic storm. The birds evacuated their breeding territories >24 hr before the arrival of the storm and atmospheric variation associated with it. The probable cue, radiating >1,000 km from tornadic storms, perceived by birds and influencing bird behavior and movements, is infrasound (i.e., sound below the range of human hearing). With the predicted increase in severity and frequency of similar storms as anthropogenic climate change progresses, understanding large-scale behavioral responses of animals to such events will be an important objective of future research.

American Avocet (Recurvirostra americana)

USGS Publications Warehouse

Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark P.; Takekawa, John Y.; Robinson, Julie A.; Oring, Lewis W.; Skorupa, Joseph P.; Boettcher, Ruth; Poole, A.

2013-01-01

This large, striking shorebird with long bluish-gray legs, a long recurved bill, and a black-and-white chevron pattern on its back and wings is one of four Avocet species in the world, the only one with distinct breeding and non-breeding plumages -- its grayish-white head and neck feathers become cinnamon in early spring as birds begin to form pairs and migrate to breeding areas.

Geographic variation in Bar-headed geese Anser indicus: connectivity of wintering and breeding grounds across a broad front

USGS Publications Warehouse

Takekawa, John Y.; Heath, Shane R.; Douglas, David C.; Perry, William M.; Javed, Sàlim; Newman, Scott H.; Suwal, Rajendra N.; Rahman, Asad R.; Choudhury, Binod C.; Prosser, Diann J.; Yan, Baoping; Hou, Yuansheng; Batbayar, Nyambayar; Natsagdorj, Tseveenmayadag; Bishop, Charles M.; Butler, Patrick J.; Frappell, Peter B.; Milsom, William K.; Scott, Graham R.; Hawkes, Lucy A.; Wikelski, Martin

2009-01-01

The connectivity and frequency of exchange between sub-populations of migratory birds is integral to understanding population dynamics over the entire species' range. True geese are highly philopatric and acquire lifetime mates during the winter, suggesting that the number of distinct sub-populations may be related to the number of distinct wintering areas. In the Bar-headed Goose Anser indicus, a species found exclusively in Central Asia, the connectivity between breeding and wintering areas is not well known. Their migration includes crossing a broad front of the Himalaya Cordillera, a significant barrier to migration for most birds. Many Bar-headed Geese fly to breeding areas on the Tibetan-Qinghai Plateau (TQP), the highest plateau in the world. From 2005-2008, 60 Bar-headed Geese were captured and marked with satellite transmitters in Nepal (n = 2), India (n = 6), China (n = 29), and Mongolia (n = 23) to examine their migration and distribution. Distinct differences were observed in their migration corridors and timing of movements, including an apparent leap-frog migration pattern for geese from Mongolia. Measurements of geese from Mongolia were larger than their counterparts from China, providing some evidence of morphological differences. Alteration of habitats in China, including the warming effects of climate change on glaciers increasing runoff to TQP wetlands, may be changing goose migration patterns and timing. With the exception of one individual, all geese from Qinghai Lake, China wintered in the southern TQP near Lhasa, and their increasing numbers in that region may be related to the effects of climate change and agricultural development. Thus, our findings document both morphological and geographical variation in sub-populations of Bar-headed Geese, but their resilience to environmental change may be lost if migratory short-stopping results in larger congregations restricted to a smaller number of wintering areas.

[Habitat use patterns of the Black Brant Branta bernicla nigricans (Anseriformes: Anatidae) in natural and artificial areas of Guerrero Negro, Baja California Sur, Mexico].

PubMed

Cedillo, Israel Martínez; Carmona, Roberto; Ward, David H; Danemann, Gustavo D

2013-06-01

The Black Brant is a common inhabitant of the Western Artic American tundra, which migrates to Southern Pacific coasts during the winter season. Approximately, 31000 birds (31%) constitute the Mexican population of Brants at Guerrero Negro, Ojo de Liebre, and Exportadora de Sal lagoon complex; nevertheless, there is little information about the distribution patterns and zone usage. At Guerrero Negro Lagoon (GNL), Ojo de Liebre Lagoon (OLL, both natural sites), and at Exportadora de Sal (ESSA, artificial site) we determined by monthly censuses (from November 2006 to April 2007, 08:00-16:00h) and observed: (1) season and site effects on population structure (age groups), and (2) the tide level relationship with the abundance and proportion of feeding birds. Within a total of 150 observation hours and 98 birds, our results showed a general 0.68 proportion of adults, that was higher in winter than in spring. The statistics analysis showed no effects by site on the proportion of feeding birds, but we observed a temporal decrease at ESSA and at GNL. In contrast the proportion of feeding birds at OLL was constant. We observed an increase in the juveniles between winter and spring. This increase is related with the differential migration, which mentions that the juveniles are the last to leave the wintering area. In winter the relations of the tide level with the abundance of Brant were: direct at ESSA, inverse at OLL and no relation found at GNL. In spring, no relation was observed in the sites. The proportion of Brants feeding at OLL (the site with the higher abundance) was independent of the tide level. This is related with two possible behaviors of the geese: (1) they can move through the lagoon and take advantage of the tidal lag, which is up to four hours; and (2) they can modify their feeding strategies, more on floating eelgrass (Zostera marina).

Thermal impact of migrating birds' wing color on their flight performance: Possibility of new generation of biologically inspired drones.

PubMed

Hassanalian, M; Abdelmoula, H; Ben Ayed, S; Abdelkefi, A

2017-05-01

The thermal impact of the birds' color on their flight performance are investigated. In most of the large migrating birds, the top of their wings is black. Considering this natural phenomenon in the migrating birds, such as albatross, a thermal analysis of the boundary layer of their wings is performed during the year depending on the solar insulation. It is shown that the temperature difference between the bright and dark colored top wing surface is around 10°C. The dark color on the top of the wing increases the temperature of the boundary layer over the wing which consequently reduces the skin drag force over the wing. This reduction in the drag force can be considered as one of the effective factors for long endurance of these migrating birds. This research should lead to improved designs of the drones by applying the inspired colors which can help drones increase their endurance. Copyright © 2017 Elsevier Ltd. All rights reserved.

The dynamics of avian influenza in western Arctic snow geese: implications for annual and migratory infection patterns

USGS Publications Warehouse

Samuel, Michael D.; Hall, Jeffrey S.; Brown, Justin D.; Goldberg, Diana R.; Ip, Hon S.; Baranyuk, Vasily V.

2015-01-01

Wild water birds are the natural reservoir for low-pathogenic avian influenza viruses (AIV). However, our ability to investigate the epizootiology of AIV in these migratory populations is challenging, and despite intensive worldwide surveillance, remains poorly understood. We conducted a cross-sectional, retrospective analysis in Pacific Flyway lesser snow geese Chen caerulescens to investigate AIV serology and infection patterns. We collected nearly 3,000 sera samples from snow geese at 2 breeding colonies in Russia and Canada during 1993-1996 and swab samples from > 4,000 birds at wintering and migration areas in the United States during 2006-2011. We found seroprevalence and annual seroconversion varied considerably among years. Seroconversion and infection rates also differed between snow goose breeding colonies and wintering areas, suggesting that AIV exposure in this gregarious waterfowl species is likely occurring during several phases (migration, wintering and potentially breeding areas) of the annual cycle. We estimated AIV antibody persistence was longer (14 months) in female geese compared to males (6 months). This relatively long period of AIV antibody persistence suggests that subtype-specific serology may be an effective tool for detection of exposure to subtypes associated with highly-pathogenic AIV. Our study provides further evidence of high seroprevalence in Arctic goose populations, and estimates of annual AIV seroconversion and antibody persistence for North American waterfowl. We suggest future AIV studies include serology to help elucidate the epizootiological dynamics of AIV in wild bird populations.

Ontogenetic development of migration: Lagrangian drift trajectories suggest a new paradigm for sea turtles.

PubMed

Hays, Graeme C; Fossette, Sabrina; Katselidis, Kostas A; Mariani, Patrizio; Schofield, Gail

2010-09-06

Long distance migration occurs in a wide variety of taxa including birds, insects, fishes, mammals and reptiles. Here, we provide evidence for a new paradigm for the determinants of migration destination. As adults, sea turtles show fidelity to their natal nesting areas and then at the end of the breeding season may migrate to distant foraging sites. For a major rookery in the Mediterranean, we simulated hatchling drift by releasing 288 000 numerical particles in an area close to the nesting beaches. We show that the pattern of adult dispersion from the breeding area reflects the extent of passive dispersion that would be experienced by hatchlings. Hence, the prevailing oceanography around nesting areas may be crucial to the selection of foraging sites used by adult sea turtles. This environmental forcing may allow the rapid evolution of new migration destinations if ocean currents alter with climate change.

Ontogenetic development of migration: Lagrangian drift trajectories suggest a new paradigm for sea turtles

PubMed Central

Hays, Graeme C.; Fossette, Sabrina; Katselidis, Kostas A.; Mariani, Patrizio; Schofield, Gail

2010-01-01

Long distance migration occurs in a wide variety of taxa including birds, insects, fishes, mammals and reptiles. Here, we provide evidence for a new paradigm for the determinants of migration destination. As adults, sea turtles show fidelity to their natal nesting areas and then at the end of the breeding season may migrate to distant foraging sites. For a major rookery in the Mediterranean, we simulated hatchling drift by releasing 288 000 numerical particles in an area close to the nesting beaches. We show that the pattern of adult dispersion from the breeding area reflects the extent of passive dispersion that would be experienced by hatchlings. Hence, the prevailing oceanography around nesting areas may be crucial to the selection of foraging sites used by adult sea turtles. This environmental forcing may allow the rapid evolution of new migration destinations if ocean currents alter with climate change. PMID:20236958

Bird mortality during nocturnal migration over Lake Michigan: A case study

USGS Publications Warehouse

Diehl, Robert H.; Bates, John M.; Willard, David E.; Gnoske, Thomas P.

2014-01-01

Millions of birds die each year during migration. Most of this mortality goes unobserved and conditions surrounding the actual events are often not thoroughly documented. We present a case study of substantial migrant casualties along the shores of southwestern Lake Michigan during May 1996 when we found 2,981 dead birds of 114 species, mostly migrant passerines. An unusual sequence of events allowed us to document the circumstances surrounding this migratory bird kill. Bird carcasses appeared on the southwestern shores of Lake Michigan in the days following storm systems that produced high rain and in one case, hail. Encounters between birds and precipitation over open water were recorded by weather radar, and were followed by winds that drifted dead birds toward highly populated shorelines where the kill was observed and documented. Climatologically, May 1996 was exceptional for producing weather conditions that both killed birds en masse and allowed the mortality to be documented. As a result, this is one of the more thoroughly documented instances of a weather-related mass mortality event during migration.

Wind effects on the migration routes of trans-Saharan soaring raptors: geographical, seasonal, and interspecific variation

PubMed Central

Vidal-Mateo, Javier; Mellone, Ugo; López-López, Pascual; La Puente, Javier De; García-Ripollés, Clara; Bermejo, Ana; Urios, Vicente

2016-01-01

Abstract Wind is among the most important environmental factors shaping birds’ migration patterns. Birds must deal with the displacement caused by crosswinds and their behavior can vary according to different factors such as flight mode, migratory season, experience, and distance to goal areas. Here we analyze the relationship between wind and migratory movements of three raptor species which migrate by soaring–gliding flight: Egyptian vulture Neophron percnopterus, booted eagle Aquila pennata, and short-toed snake eagle Circaetus gallicus. We analyzed daily migratory segments (i.e., the path joining consecutive roosting locations) using data recorded by GPS satellite telemetry. Daily movements of Egyptian vultures and booted eagles were significantly affected by tailwinds during both autumn and spring migrations. In contrast, daily movements of short-toed eagles were only significantly affected by tailwinds during autumn migration. The effect of crosswinds was significant in all cases. Interestingly, Egyptian vultures and booted eagles showed latitudinal differences in their behavior: both species compensated more frequently at the onset of autumn migration and, at the end of the season when reaching their wintering areas, the proportion of drift segments was higher. In contrast, there was a higher drift at the onset of spring migration and a higher compensation at the end. Our results highlight the effect of wind patterns on the migratory routes of soaring raptors, with different outcomes in relation to species, season, and latitude, ultimately shaping the loop migration patterns that current tracking techniques are showing to be widespread in many long distance migrants. PMID:29491895

Notes on winter feeding behavior and molt in Wilson's phalaropes

USGS Publications Warehouse

Burger, J.; Howe, M.

1975-01-01

Wilson's Phalaropes, Steganopus tricolor, migrate in late summer from the prairie regions of North America to their wintering grounds in the highlands of Peru and the inland and coastal waters of Chile, Bolivia, Paraguay, Uruguay, and Argentina (Holmes 1939, Meyer de Schauensee 1970). Reports on these birds from their wintering habitat are few. This paper describes numbers, feeding behavior, and molt of Wilson's Phalaropes wintering in a freshwater marsh in central Argentina. Fieldwork in Argentina was conducted by the senior author. The junior author analyzed molt patterns of birds collected there and added data he collected in North Dakota in 1968 and 1969.

Intercontinental Spread of Asian-Origin H5N8 to North America through Beringia by Migratory Birds.

PubMed

Lee, Dong-Hun; Torchetti, Mia Kim; Winker, Kevin; Ip, Hon S; Song, Chang-Seon; Swayne, David E

2015-06-01

Phylogenetic network analysis and understanding of waterfowl migration patterns suggest that the Eurasian H5N8 clade 2.3.4.4 avian influenza virus emerged in late 2013 in China, spread in early 2014 to South Korea and Japan, and reached Siberia and Beringia by summer 2014 via migratory birds. Three genetically distinct subgroups emerged and subsequently spread along different flyways during fall 2014 into Europe, North America, and East Asia, respectively. All three subgroups reappeared in Japan, a wintering site for waterfowl from Eurasia and parts of North America. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Ticks (Ixodidae) on birds migrating from Europe and Asia to Africa, 1959-61*

PubMed Central

Hoogstraal, Harry; Kaiser, Makram N.; Traylor, Melvin A.; Guindy, Ezzat; Gaber, Sobhy

1963-01-01

The need for imaginative thinking and research in the epidemiology of diseases transmitted by arthropods is made manifest by new views of the longevity and host ranges of arthropod-borne viruses, as well as by other biological and medical phenomena. Among these is the intercontinental transport of ticks by migrating birds. During the fall migration periods of 1959, 1960 and 1961, 32 086 birds (comprising 72 forms) were examined for ticks in Egypt while en route from Asia and eastern Europe to tropical Africa. Of these, 40 forms, represented by 31 434 birds, were tick-infested. The bird hosts, numbering 1040 (3.31% of the tick-infested bird forms examined), bore 1761 ticks, or 1.69 ticks per host. Common ticks taken were Hyalomma m. marginatum, Haemaphysalis punctata, and Ixodes ricinus. Ixodes frontalis and Hyalomma aegyptium were less common and Haemaphysalis sulcata, H. otophila, and H. pavlovskyi were rare. The common tick species are known to be reservoirs and vectors of pathogens causing a number of human and animal diseases in Europe and Asia. Several of the bird hosts have also been incriminated as reservoirs in their summer ranges. Over 20 strains of pathogenic viruses were isolated from these birds and their ticks in Egypt in the 1961 fall migration period. The most difficult problems in investigations such as this in many parts of the world are taxonomic ones: the correct identification of bird hosts, of immature stages of ticks and of viruses. PMID:13961632

Effects of habitat fragmentation on passerine birds breeding in Intermountain shrubsteppe

USGS Publications Warehouse

Knick, S.T.; Rotenberry, J.T.

2002-01-01

Habitat fragmentation and loss strongly influence the distribution and abundance of passerine birds breeding in Intermountain shrubsteppe. Wildfires, human activities, and change in vegetation communities often are synergistic in these systems and can result in radical conversion from shrubland to grasslands dominated by exotic annuals at large temporal and spatial scales from which recovery to native conditions is unlikely. As a result, populations of 5 of the 12 species in our review of Intermountain shrubsteppe birds are undergoing significant declines; 5 species are listed as at-risk or as candidates for protection in at least one state. The process by which fragmentation affects bird distributions in these habitats remains unknown because most research has emphasized the detection of population trends and patterns of habitat associations at relatively large spatial scales. Our research indicates that the distribution of shrubland-obligate species, such as Brewer's Sparrows (Spizella breweri), Sage Sparrows (Amphispiza belli), and Sage Thrashers (Oreoscoptes montanus), was highly sensitive to fragmentation of shrublands at spatial scales larger than individual home ranges. In contrast, the underlying mechanisms for both habitat change and bird population dynamics may operate independently of habitat boundaries. We propose alternative, but not necessarily exclusive, mechanisms to explain the relationship between habitat fragmentation and bird distribution and abundance. Fragmentation might influence productivity through differences in breeding density, nesting success, or predation. However, local and landscape variables were not significant determinants either of success, number fledged, or probability of predation or parasitism (although our tests had relatively low statistical power). Alternatively, relative absence of natal philopatry and redistribution by individuals among habitats following fledging or post-migration could account for the pattern of distribution and abundance. Thus, boundary dynamics may be important in determining the distribution of shrubland-obligate species but insignificant relative to the mechanisms causing the pattern of habitat and bird distribution. Because of the dichotomy in responses, Intermountain shrubsteppe systems present a unique challenge in understanding how landscape composition, configuration, and change influence bird population dynamics.

Energy Reserves, Information Need and a Pinch of Personality Determine Decision-Making on Route in Partially Migratory Blue Tits.

PubMed

Nilsson, Anna L K; Nilsson, Jan-Åke; Mettke-Hofmann, Claudia

2016-01-01

In facultative partial migrants some individuals in a population are migratory and others are resident and individuals decide each year anew which strategy to choose. While the proportion of birds migrating is in part determined by environmental conditions and competitive abilities, the timing of individual departure and behaviours on route are little understood. Individuals encounter different environmental conditions when migrating earlier or later. Based on cost/ benefit considerations we tested whether behaviours on route were affected by time constraints, personality and/or age in a partially migrating population of Blue tits (Cyanistes caeruleus). We captured female Blue tits on migration at the Southern tip of Sweden during early, peak and late migration and measured latency to feed in an unfamiliar environment, exploration of a novel object and hesitation to feed beside a novel object (neophobia). Lean birds and birds with long wings started feeding earlier when released into the cage indicating that foraging decisions were mainly determined by energetic needs (lean and large birds). However, juveniles commenced feeding later with progression of the migratory season in concordance with predictions about personality effects. Furthermore, lean birds started to explore earlier than birds with larger fat reserves again indicating an effect of maintaining threshold energy reserves. Moreover, late migrating juveniles, started to explore earlier than early migrating juveniles possibly due to time constraints to find high-quality foraging patches or a suitable winter home. Finally, neophobia did not change over the migratory season indicating that this behaviour is not compromised by time constraints. The results overall indicate that decisions on route are mainly governed by energetic requirements and current needs to learn about the environment and only to a small extent by differences in personality.

Energy Reserves, Information Need and a Pinch of Personality Determine Decision-Making on Route in Partially Migratory Blue Tits

PubMed Central

Nilsson, Jan-Åke; Mettke-Hofmann, Claudia

2016-01-01

In facultative partial migrants some individuals in a population are migratory and others are resident and individuals decide each year anew which strategy to choose. While the proportion of birds migrating is in part determined by environmental conditions and competitive abilities, the timing of individual departure and behaviours on route are little understood. Individuals encounter different environmental conditions when migrating earlier or later. Based on cost/ benefit considerations we tested whether behaviours on route were affected by time constraints, personality and/or age in a partially migrating population of Blue tits (Cyanistes caeruleus). We captured female Blue tits on migration at the Southern tip of Sweden during early, peak and late migration and measured latency to feed in an unfamiliar environment, exploration of a novel object and hesitation to feed beside a novel object (neophobia). Lean birds and birds with long wings started feeding earlier when released into the cage indicating that foraging decisions were mainly determined by energetic needs (lean and large birds). However, juveniles commenced feeding later with progression of the migratory season in concordance with predictions about personality effects. Furthermore, lean birds started to explore earlier than birds with larger fat reserves again indicating an effect of maintaining threshold energy reserves. Moreover, late migrating juveniles, started to explore earlier than early migrating juveniles possibly due to time constraints to find high-quality foraging patches or a suitable winter home. Finally, neophobia did not change over the migratory season indicating that this behaviour is not compromised by time constraints. The results overall indicate that decisions on route are mainly governed by energetic requirements and current needs to learn about the environment and only to a small extent by differences in personality. PMID:27732602

Remotely sensed wind speed predicts soaring behaviour in a wide-ranging pelagic seabird.

PubMed

Gibb, Rory; Shoji, Akiko; Fayet, Annette L; Perrins, Chris M; Guilford, Tim; Freeman, Robin

2017-07-01

Global wind patterns affect flight strategies in many birds, including pelagic seabirds, many of which use wind-powered soaring to reduce energy costs during at-sea foraging trips and migration. Such long-distance movement patterns are underpinned by local interactions between wind conditions and flight behaviour, but these fine-scale relationships are far less well understood. Here we show that remotely sensed ocean wind speed and direction are highly significant predictors of soaring behaviour in a migratory pelagic seabird, the Manx shearwater ( Puffinus puffinus ). We used high-frequency GPS tracking data (10 Hz) and statistical behaviour state classification to identify two energetic modes in at-sea flight, corresponding to flap-like and soar-like flight. We show that soaring is significantly more likely to occur in tailwinds and crosswinds above a wind speed threshold of around 8 m s -1 , suggesting that these conditions enable birds to reduce metabolic costs by preferentially soaring over flapping. Our results suggest a behavioural mechanism by which wind conditions may shape foraging and migration ecology in pelagic seabirds, and thus indicate that shifts in wind patterns driven by climate change could impact this and other species. They also emphasize the emerging potential of high-frequency GPS biologgers to provide detailed quantitative insights into fine-scale flight behaviour in free-living animals. © 2017 The Author(s).

Landscape associations of birds during migratory stopover

NASA Astrophysics Data System (ADS)

Diehl, Robert Howard

The challenge for migratory bird conservation is habitat preservation that sustains breeding, migration, and non-breeding biological processes. In choosing an appropriately scaled conservation arena for habitat preservation, a conservative and thorough examination of stopover habitat use patterns by migrants works back from the larger scales at which such relationships may occur. Because the use of stopover habitats by migrating birds occurs at spatial scales larger than traditional field techniques can easily accommodate, I quantify these relationship using the United States system of weather surveillance radars (popularly known as NEXRAD). To provide perspective on use of this system for biologists, I first describe the technical challenges as well as some of the biological potential of these radars for ornithological research. Using data from these radars, I then examined the influence of Lake Michigan and the distribution of woodland habitat on migrant concentrations in northeastern Illinois habitats during stopover. Lake Michigan exerted less influence on migrant abundance and density than the distribution and availability of habitat for stopover. There was evidence of post-migratory movement resulting in habitats within suburban landscapes experiencing higher migrant abundance but lower migrant density than habitats within nearby urban and agricultural landscapes. Finally, in the context of hierarchy theory, I examined the influence of landscape ecological and behavioral processes on bird density during migratory stopover. Migrant abundance did not vary across landscapes that differed considerably in the amount of habitat available for stopover. As a result, smaller, more isolated patches held higher densities of birds. Spatial models of migrant habitat selection based on migrant proximity to a patch explained nearly as much variance in the number of migrants occupying patches (R2 = 0.88) as selection models based on migrant interception of patches during flight (R2 = 0.90). Because migrant densities in specific patches were the consequence of biological processes operating at larger spatial scales, sound conservation strategies for migrating landbirds should consider the landscape context of stopover habitats that are potential targets for preservation.

Limitations and mechanisms influencing the migratory performance of soaring birds

Treesearch

Tricia A. Miller; Brooks Robert P.; Michael J. Lanzone; David Brandes; Jeff Cooper; Junior A. Tremblay; Jay Wilhelm; Adam Duerr; Todd E. Katzner

2016-01-01

Migration is costly in terms of time, energy and safety. Optimal migration theory suggests that individual migratory birds will choose between these three costs depending on their motivation and available resources. To test hypotheses about use of migratory strategies by large soaring birds, we used GPS telemetry to track 18 adult, 13 sub-adult and 15 juvenile Golden...

Tornadic storm avoidance behavior in breeding songbirds.

PubMed

Streby, Henry M; Kramer, Gunnar R; Peterson, Sean M; Lehman, Justin A; Buehler, David A; Andersen, David E

2015-01-05

Migration is a common behavior used by animals of many taxa to occupy different habitats during different periods. Migrant birds are categorized as either facultative (i.e., those that are forced to migrate by some proximal cue, often weather) or obligate (i.e., those that migrate on a regular cycle). During migration, obligate migrants can curtail or delay flights in response to inclement weather or until favorable winds prevail, and they can temporarily reorient or reverse direction when ecological or meteorological obstacles are encountered. However, it is not known whether obligate migrants undertake facultative migrations and make large-scale movements in response to proximal cues outside of their regular migration periods. Here, we present the first documentation of obligate long-distance migrant birds undertaking a facultative migration, wherein breeding golden-winged warblers (Vermivora chrysoptera) carrying light-level geolocators performed a >1,500 km 5-day circumvention of a severe tornadic storm. The birds evacuated their breeding territories >24 hr before the arrival of the storm and atmospheric variation associated with it. The probable cue, radiating >1,000 km from tornadic storms, perceived by birds and influencing bird behavior and movements, is infrasound (i.e., sound below the range of human hearing). With the predicted increase in severity and frequency of similar storms as anthropogenic climate change progresses, understanding large-scale behavioral responses of animals to such events will be an important objective of future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

Artificial light at night confounds broad-scale habitat use by migrating birds

USGS Publications Warehouse

McLaren, James D.; Buler, Jeffrey J.; Schreckengost, Tim; Smolinsky, Jaclyn A.; Boone, Matthew; van Loon, E. Emiel; Dawson, Deanna K.; Walters, Eric L.

2018-01-01

With many of the world's migratory bird populations in alarming decline, broad-scale assessments of responses to migratory hazards may prove crucial to successful conservation efforts. Most birds migrate at night through increasingly light-polluted skies. Bright light sources can attract airborne migrants and lead to collisions with structures, but might also influence selection of migratory stopover habitat and thereby acquisition of food resources. We demonstrate, using multi-year weather radar measurements of nocturnal migrants across the northeastern U.S., that autumnal migrant stopover density increased at regional scales with proximity to the brightest areas, but decreased within a few kilometers of brightly-lit sources. This finding implies broad-scale attraction to artificial light while airborne, impeding selection for extensive forest habitat. Given that high-quality stopover habitat is critical to successful migration, and hindrances during migration can decrease fitness, artificial lights present a potentially heightened conservation concern for migratory bird populations.

Long-term changes in migration timing of Song Thrush Turdus philomelos at the southern Baltic coast in response to temperatures on route and at breeding grounds.

PubMed

Redlisiak, Michał; Remisiewicz, Magdalena; Nowakowski, Jarosław K

2018-05-26

Climate warming causes the advancement of spring arrival of many migrant birds breeding in Europe, but the effects on their autumn migration are less known. We aimed to determine any changes in the timing of Song Thrush captured during spring and autumn migrations at the Polish Baltic coast from 1975 to 2014, and if these were related to long-term changes of temperature at their breeding grounds and migration routes. The timing of spring migration at Hel ringing station in 1975-2014 did not show long-term advance, but they had responded to environmental conditions on the year-to-year basis. The warmer the temperatures were in April on their migration route, the earlier were the dates of the median and the end of spring migration at Hel. The beginning of autumn migration at the Mierzeja Wiślana ringing station advanced by 5 days between 1975 and 2014. The warmer the April on route, and the July at the Song Thrushes' breeding grounds, the earlier young birds began autumn migration across the Baltic coast. We suggest this was a combined effect of adults' migration and breeding early during warm springs and young birds getting ready faster for autumn migration during warm summers. The average time span of 90% of the autumn migration was extended by 5 days, probably because of early migration of young birds from first broods and late of those from second broods enabled by warm springs and summers. The response of Song Thrushes' migration timing to temperatures on route and at the breeding grounds indicated high plasticity in the species and suggested it might adapt well to climate changes.

Migration patterns and wintering range of common loons breeding in the Northeastern United States

USGS Publications Warehouse

Kenow, K.P.; Adams, D.; Schoch, N.; Evers, D.C.; Hanson, W.; Yates, D.; Savoy, L.; Fox, T.J.; Major, A.; Kratt, R.; Ozard, J.

2009-01-01

A study, using satellite telemetry, was conducted to determine the precise migration patterns and wintering locations of Common Loons (Gavia immer) breeding in the northeastern United States. Transmitters were implanted in 17 loons (16 adults and one juvenile) that were captured on breeding lakes in New York, New Hampshire, and Maine during the summers of 2003, 2004, and 2005. Transmitters from ten of the birds provided adequate location data to document movement to wintering areas. Most adult loons appeared to travel non-stop from breeding lakes, or neighboring lakes (within 15 km), to the Atlantic coast. Adult loons marked in New Hampshire and Maine wintered 152 to 239 km from breeding lakes, along the Maine coast. Adult loons marked in the Adirondack Park of New York wintered along the coasts of Massachusetts (414 km from breeding lake), Rhode Island (362 km), and southern New Jersey (527 km). Most of the loons remained relatively stationary throughout the winter, but the size of individual wintering areas of adult loons ranged from 43 to 1,159 km 2, based on a 95% fixed kernel utilization distribution probability. A juvenile bird from New York made a number of stops at lakes and reservoirs en route to Long Island Sound (325 km from breeding lake). Maximum functional life of transmitters was about 12 months, providing an opportunity to document spring migration movements as well. This work provides essential information for development and implementation of regional Common Loon conservation strategies in the Northeastern U.S.

A fall land bird migration across the South China Sea from Indo-China to the Greater Sunda Islands

USGS Publications Warehouse

Ellis, D.H.; Kepler, A.K.; Kepler, C.B.

1994-01-01

We encountered 150 land birds representing 14 families along the cruise track of the Soviet Oceanographic Research Vessel AKADEMlK KOROLEV in the South China Sea. We saw most of these birds during a 3 -day period in a small area c. 350 km southeast of the southern tip of the Indo-China peninsula. These observations suggest that a significant land bird migration corridor crosses the South China Sea from Viet Nam to Borneo.

Application of Johnson et al.'s speciation threshold model to apparent colonization times of island biotas.

PubMed

Ricklefs, Robert E; Bermingham, Eldredge

2004-08-01

Understanding patterns of diversity can be furthered by analysis of the dynamics of colonization, speciation, and extinction on islands using historical information provided by molecular phylogeography. The land birds of the Lesser Antilles are one of the most thoroughly described regional faunas in this context. In an analysis of colonization times, Ricklefs and Bermingham (2001) found that the cumulative distribution of lineages with respect to increasing time since colonization exhibits a striking change in slope at a genetic distance of about 2% mitochondrial DNA sequence divergence (about one million years). They further showed how this heterogeneity could be explained by either an abrupt increase in colonization rates or a mass extinction event. Cherry et al. (2002), referring to a model developed by Johnson et al. (2000), argued instead that the pattern resulted from a speciation threshold for reproductive isolation of island populations from their continental source populations. Prior to this threshold, genetic divergence is slowed by migration from the source, and species of varying age accumulate at a low genetic distance. After the threshold is reached, source and island populations diverge more rapidly, creating heterogeneity in the distribution of apparent ages of island taxa. We simulated of Johnson et al.'s speciation-threshold model, incorporating genetic divergence at rate k and fixation at rate M of genes that have migrated between the source and the island population. Fixation resets the divergence clock to zero. The speciation-threshold model fits the distribution of divergence times of Lesser Antillean birds well with biologically plausible parameter estimates. Application of the model to the Hawaiian avifauna, which does not exhibit marked heterogeneity of genetic divergence, and the West Indian herpetofauna, which does, required unreasonably high migration-fixation rates, several orders of magnitude greater than the colonization rate. However, the plausibility of the speciation-divergence model for Lesser Antillean birds emphasizes the importance of further investigation of historical biogeography on a regional scale for whole biotas, as well as the migration of genes between populations on long time scales and the achievement of reproductive isolation.

Convergence of broad-scale migration strategies in terrestrial birds.

PubMed

La Sorte, Frank A; Fink, Daniel; Hochachka, Wesley M; Kelling, Steve

2016-01-27

Migration is a common strategy used by birds that breed in seasonal environments. Selection for greater migration efficiency is likely to be stronger for terrestrial species whose migration strategies require non-stop transoceanic crossings. If multiple species use the same transoceanic flyway, then we expect the migration strategies of these species to converge geographically towards the most optimal solution. We test this by examining population-level migration trajectories within the Western Hemisphere for 118 migratory species using occurrence information from eBird. Geographical convergence of migration strategies was evident within specific terrestrial regions where geomorphological features such as mountains or isthmuses constrained overland migration. Convergence was also evident for transoceanic migrants that crossed the Gulf of Mexico or Atlantic Ocean. Here, annual population-level movements were characterized by clockwise looped trajectories, which resulted in faster but more circuitous journeys in the spring and more direct journeys in the autumn. These findings suggest that the unique constraints and requirements associated with transoceanic migration have promoted the spatial convergence of migration strategies. The combination of seasonal atmospheric and environmental conditions that has facilitated the use of similar broad-scale migration strategies may be especially prone to disruption under climate and land-use change. © 2016 The Author(s).

Modeling Bird Migration in Changing Habitats: Space-based Ornithology using Satellites and GIS

NASA Technical Reports Server (NTRS)

Smith, James A.; Deppe, Jill L.

2008-01-01

Understanding bird migration and avian biodiversity is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties presenting challenges in both geographic space and time. Space based technology, coupled with geographic information systems, yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At NASA, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. In our work, we use individual organism biophysical models and drive these models with satellite observations and numerical weather predictions of the spatio-temporal gradients in climate and habitat. Geographic information system technology comprises one component of our overall simulation framework, especially for characterizing the changing habitats and conditions encountered by en-route migratory birds. Simulation provides a tool for studying bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. We present examples of our simulation of shorebirds, principally, pectoral sandpipers, along the central flyways of the United States and Canada from the Gulf of Mexico to Alaska.

Species-specific accumulation of polybrominated diphenyl ethers (PBDEs) and other emerging flame retardants in several species of birds from Korea.

PubMed

Jin, Xiangzi; Lee, Sunggyu; Jeong, Yunsun; Yu, Jae-Pyoung; Baek, Woon Kee; Shin, Kyung-Hoon; Kannan, Kurunthachalam; Moon, Hyo-Bang

2016-12-01

Few studies have been conducted on the alternatives to legacy flame retardants in avian species worldwide. In this study, polybrominated diphenyl ethers (PBDEs) and alternative flame retardants such as novel brominated flame retardants (NBFRs) and dechlorane plus (DP) were determined in livers of 10 species of birds from Korea to elucidate species-specific accumulation, biological factors that affect accumulation, and bioaccumulation potentials of these contaminants. Among the emerging alternative flame retardants, the highest occurrence was found for bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEHTBP), syn-DP, anti-DP, and decabromodiphenyl ethane (DBDPE). PBDE concentrations (median: 17.1 ng/g lipid wt) measured in our study were within the ranges reported in previous studies, while the concentrations of BEHTBP, BTBPE and DP were greater than those reported earlier. Residential predatory birds showed significantly greater concentrations of PBDEs and NBFRs than migratory predators and passerine birds. The concentrations of PBDEs, BEHTBP, and DP in residential predatory birds were significantly correlated with increasing stable nitrogen isotope ratio (δ 15 N), which indicated biomagnification potentials of these contaminants. Our results suggest that the concentrations and accumulation patterns of PBDEs, NBFRs, and DP depend on the feeding habits and migration patterns of avian species. This is the first report on the accumulation of emerging alternatives to PBDEs in birds from Korea. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bird Strike Risk for Space Launch Vehicles

NASA Technical Reports Server (NTRS)

Hales, Christy; Czech, Matthew

2017-01-01

Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. This presentation will outline an approach for estimating risk resulting from bird strikes to space launch vehicles. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts all affect the risk due to bird strike. Lessons learned, challenges over lack of data, and significant risk contributors will be discussed.

Characterizing stopover sites of migrating passerine birds in the lower Chesapeake Bay region for conservation: an integrated radar-habitat study

USGS Publications Warehouse

Mabey, S.; Watts, B.; Paxton, B.; Smith, F.; Truitt, B.; Dawson, D.

2005-01-01

Many conservation organizations and initiatives including Partners-in-Flight and the U.S. Fish and Wildlife Service's regional Joint Ventures have identified migratory songbird stopover habitat as a priority conservation target. However, the spatial and temporal variability inherent in migration presents a number of challenges to both identifying and characterizing stopover habitat. Scarce conservation resources further demand that stopover sites be classified on a scale of priority so that conservation action can proceed according to ecological value. We are applying weather surveillance radar data collected from the National Weather Service WSR-88D at Wakefield, VA, and NASA's Doppler radar, NPOL, in Oyster, VA, to identify passerine stopover sites in the lower Chesapeake Bay region and develop spatial models to characterize these sites based on relative migrant abundance and consistency of use between and within seasons. We are using the stopover patterns to generate hypotheses regarding the habitat, geographic, and stochastic factors contributing to the distribution of migrants at a regional scale. We are testing these hypotheses with detailed habitat data and ground surveys of migrating birds with the goal of creating a generalized prioritization system for stopover site conservation.

True navigation in migrating gulls requires intact olfactory nerves

PubMed Central

Wikelski, Martin; Arriero, Elena; Gagliardo, Anna; Holland, Richard A.; Huttunen, Markku J.; Juvaste, Risto; Mueller, Inge; Tertitski, Grigori; Thorup, Kasper; Wild, Martin; Alanko, Markku; Bairlein, Franz; Cherenkov, Alexander; Cameron, Alison; Flatz, Reinhard; Hannila, Juhani; Hüppop, Ommo; Kangasniemi, Markku; Kranstauber, Bart; Penttinen, Maija-Liisa; Safi, Kamran; Semashko, Vladimir; Schmid, Heidi; Wistbacka, Ralf

2015-01-01

During migratory journeys, birds may become displaced from their normal migratory route. Experimental evidence has shown that adult birds can correct for such displacements and return to their goal. However, the nature of the cues used by migratory birds to perform long distance navigation is still debated. In this experiment we subjected adult lesser black-backed gulls migrating from their Finnish/Russian breeding grounds (from >60°N) to Africa (to < 5°N) to sensory manipulation, to determine the sensory systems required for navigation. We translocated birds westward (1080 km) or eastward (885 km) to simulate natural navigational challenges. When translocated westwards and outside their migratory corridor birds with olfactory nerve section kept a clear directional preference (southerly) but were unable to compensate for the displacement, while intact birds and gulls with the ophthalmic branch of the trigeminal nerve sectioned oriented towards their population-specific migratory corridor. Thus, air-borne olfactory information seems to be important for migrating gulls to navigate successfully in some circumstances. PMID:26597351

True navigation in migrating gulls requires intact olfactory nerves.

PubMed

Wikelski, Martin; Arriero, Elena; Gagliardo, Anna; Holland, Richard A; Huttunen, Markku J; Juvaste, Risto; Mueller, Inge; Tertitski, Grigori; Thorup, Kasper; Wild, Martin; Alanko, Markku; Bairlein, Franz; Cherenkov, Alexander; Cameron, Alison; Flatz, Reinhard; Hannila, Juhani; Hüppop, Ommo; Kangasniemi, Markku; Kranstauber, Bart; Penttinen, Maija-Liisa; Safi, Kamran; Semashko, Vladimir; Schmid, Heidi; Wistbacka, Ralf

2015-11-24

During migratory journeys, birds may become displaced from their normal migratory route. Experimental evidence has shown that adult birds can correct for such displacements and return to their goal. However, the nature of the cues used by migratory birds to perform long distance navigation is still debated. In this experiment we subjected adult lesser black-backed gulls migrating from their Finnish/Russian breeding grounds (from >60°N) to Africa (to < 5°N) to sensory manipulation, to determine the sensory systems required for navigation. We translocated birds westward (1080 km) or eastward (885 km) to simulate natural navigational challenges. When translocated westwards and outside their migratory corridor birds with olfactory nerve section kept a clear directional preference (southerly) but were unable to compensate for the displacement, while intact birds and gulls with the ophthalmic branch of the trigeminal nerve sectioned oriented towards their population-specific migratory corridor. Thus, air-borne olfactory information seems to be important for migrating gulls to navigate successfully in some circumstances.

Possible linkage between neuronal recruitment and flight distance in migratory birds

PubMed Central

Barkan, Shay; Roll, Uri; Yom-Tov, Yoram; Wassenaar, Leonard I.; Barnea, Anat

2016-01-01

New neuronal recruitment in an adult animal’s brain is presumed to contribute to brain plasticity and increase the animal’s ability to contend with new and changing environments. During long-distance migration, birds migrating greater distances are exposed to more diverse spatial information. Thus, we hypothesized that greater migration distance in birds would correlate with the recruitment of new neurons into the brain regions involved with migratory navigation. We tested this hypothesis on two Palearctic migrants - reed warblers (Acrocephalus scirpaceus) and turtle doves (Streptopelia turtur), caught in Israel while returning from Africa in spring and summer. Birds were injected with a neuronal birth marker and later inspected for new neurons in brain regions known to play a role in navigation - the hippocampus and nidopallium caudolateral. We calculated the migration distance of each individual by matching feather isotopic values (δ2H and δ13C) to winter base-maps of these isotopes in Africa. Our findings suggest a positive correlation between migration distance and new neuronal recruitment in two brain regions - the hippocampus in reed warblers and nidopallium caudolateral in turtle doves. This multidisciplinary approach provides new insights into the ability of the avian brain to adapt to different migration challenges. PMID:26905978

Motorized Migrations: the Future or Mere Fantasy?

USGS Publications Warehouse

Ellis, D.H.; Sladen, William J. L.; Lishman, W.A.; Clegg, K.R.; Duff, J.W.; Gee, G.F.; Lewis, J.C.

2003-01-01

In 15 experiments from 1993-2002, we led cranes, geese, or swans on their first southward migration with either ultralight aircraft or vehicles on the ground. These experiments reveal that large birds can be readily trained to follow and most will return north (and south) in subsequent migrations unassisted. These techniques can now be used to teach birds new (or forgotten) migration paths. Although we are constantly improving our training techniques, we now have an operational program that can be broadly applied to those species where juveniles learn migration routes from their parents.

Ticks (Ixodidae) on migrating birds in Egypt, spring and fall 1962*

PubMed Central

Hoogstraal, Harry; Traylor, Melvin A.; Gaber, Sobhy; Malakatis, George; Guindy, Ezzat; Helmy, Ibrahim

1964-01-01

Over a number of years studies have been carried out in Egypt on the transport by migrating birds of ticks that may transmit pathogens of man and animals. In continuation of these investigations 11 036 birds migrating southwards through Egypt were examined for ticks during the fall of 1962. The 881 infested birds (comprising 24 species and sub-species represented by 10 612 individuals) yielded 1442 ticks. Tick-host relationships were similar to those of previous years except that in 1962 the prevalence of infestation was almost invariably much higher than the averages for 1959-61. Five species of birds were added to the previous list of 40 infested forms. Previously unrecorded tick species taken during 1962 were Ixodes redikorzevi (a species from Asia very occasionally found in rodent burrows in Egypt), the rare Haemaphysalis inermis, and Hyalomma a. anatolicum, H. anatolicum excavatum and H. dromedarii, which may have been carried from Asia or have attached themselves to the birds at the time of netting. During the spring of 1962, altogether 1774 birds migrating northwards through Egypt were also examined. The 56 tick-infested birds (comprising 13 species represented by 867 individuals) yielded 186 ticks. As in previous years, Hyalomma marginatum rufipes was the chief species (89.25%) parasitizing spring migrants. A single specimen of Amblyomma variegatum was taken on Anthus cervinus and 19 specimens of Ixodes?sp. nov. were collected from Sylvia c. communis and Motacilla a. alba. PMID:14163959

[Radar as imaging tool in ecology and conservation biology].

PubMed

Matyjasiak, Piotr

2017-01-01

Migrations and dispersal are among the most important ecological processes that shape ecosystems and influence our economy, health and safety. Movements of birds, bats and insects occur in a large spatial scale - regional, continental, or intercontinental. However, studies of these phenomena using classic methods are usually local. Breakthrough came with the development of radar technology, which enabled researchers to study animal movements in the atmosphere in a large spatial and temporal scale. The aim of this article was to present the radar imaging methods used in the research of aerial movements of birds, bats and insects. The types of radars used in research are described, and examples of the use of radar in basic research and in conservation biology are discussed. Radar visualizations are used in studies on the effect of meteorological conditions on bird migration, on spatial and temporal dynamics of movements of birds, bats and insects, and on the mechanism of orientation of migrating birds and insects. In conservation biology research radars are used in the monitoring of endangered species of birds and bats, to monitor bird activity at airports, as well as in assessing the impact of high constructions on flying birds and bats.

Ecologic Immunology of Avian Influenza (H5N1) in Migratory Birds

PubMed Central

Stilianakis, Nikolaos I.

2007-01-01

The claim that migratory birds are responsible for the long-distance spread of highly pathogenic avian influenza viruses of subtype H5N1 rests on the assumption that infected wild birds can remain asymptomatic and migrate long distances unhampered. We critically assess this claim from the perspective of ecologic immunology, a research field that analyzes immune function in an ecologic, physiologic, and evolutionary context. Long-distance migration is one of the most demanding activities in the animal world. We show that several studies demonstrate that such prolonged, intense exercise leads to immunosuppression and that migratory performance is negatively affected by infections. These findings make it unlikely that wild birds can spread the virus along established long-distance migration pathways. However, infected, symptomatic wild birds may act as vectors over shorter distances, as appears to have occurred in Europe in early 2006. PMID:17953082

Global change and the distributional dynamics of migratory bird populations wintering in Central America.

PubMed

La Sorte, Frank A; Fink, Daniel; Blancher, Peter J; Rodewald, Amanda D; Ruiz-Gutierrez, Viviana; Rosenberg, Kenneth V; Hochachka, Wesley M; Verburg, Peter H; Kelling, Steve

2017-12-01

Understanding the susceptibility of highly mobile taxa such as migratory birds to global change requires information on geographic patterns of occurrence across the annual cycle. Neotropical migrants that breed in North America and winter in Central America occur in high concentrations on their non-breeding grounds where they spend the majority of the year and where habitat loss has been associated with population declines. Here, we use eBird data to model weekly patterns of abundance and occurrence for 21 forest passerine species that winter in Central America. We estimate species' distributional dynamics across the annual cycle, which we use to determine how species are currently associated with public protected areas and projected changes in climate and land-use. The effects of global change on the non-breeding grounds is characterized by decreasing precipitation, especially during the summer, and the conversion of forest to cropland, grassland, or peri-urban. The effects of global change on the breeding grounds are characterized by increasing winter precipitation, higher temperatures, and the conversion of forest to peri-urban. During spring and autumn migration, species are projected to encounter higher temperatures, forests that have been converted to peri-urban, and increased precipitation during spring migration. Based on current distributional dynamics, susceptibility to global change is characterized by the loss of forested habitats on the non-breeding grounds, warming temperatures during migration and on the breeding grounds, and declining summer rainfall on the non-breeding grounds. Public protected areas with low and medium protection status are more prevalent on the non-breeding grounds, suggesting that management opportunities currently exist to mitigate near-term non-breeding habitat losses. These efforts would affect more individuals of more species during a longer period of the annual cycle, which may create additional opportunities for species to respond to changes in habitat or phenology that are likely to develop under climate change. © 2017 John Wiley & Sons Ltd.

Wind assistance: A requirement for migration of shorebirds?

USGS Publications Warehouse

Butler, Robert W.; Williams, Tony D.; Warnock, Nils; Bishop, Mary Anne

1997-01-01

We investigated the importance of wind-assisted flight for northward (spring) migration by Western Sandpipers (Calidris mauri) along the Pacific Coast of North America. Using current models of energy costs of flight and recent data on the phenology of migration, we estimated the energy (fat) requirements for migration in calm winds and with wind-assisted flight for different rates of fat deposition: (1) a variable rate, assuming that birds deposit the minimum amount of fat required to reach the next stopover site; (2) a constant maximum rate of 1.0 g/day; and (3) a lower constant rate of 0.4 g/day. We tested these models by comparing conservative estimates of predicted body mass along the migration route with empirical data on body mass of Western Sandpipers at different stopover sites and upon arrival at the breeding grounds. In calm conditions, birds would have to deposit unrealistically high amounts of fat (up to 330% of observed values) to maintain body mass above absolute lean mass values. Fat-deposition rates of 1.0 g/day and 0.4 g/day, in calm conditions, resulted in a steady decline in body mass along the migration route, with predicted body masses on arrival in Alaska of only 60% (13.6 g) and 26% (5.9 g) of average lean mass (22.7 g). Conversely, birds migrating with wind assistance would be able to complete migration with fat-deposition rates as low as 0.4 g/day, similar to values reported for this size bird from field studies. Our results extend the conclusion of the importance of winds for large, long-distance migrants to a small, short-distance migrant. We suggest that the migratory decisions of birds are more strongly influenced by the frequency and duration of winds aloft, i.e. by events during the flight phase, than by events during the stopover phase of migration, such as fat-deposition rate, that have been the focus of much recent migration theory.

Risk Considerations of Bird Strikes to Space Launch Vehicles

NASA Technical Reports Server (NTRS)

Hales, Christy; Ring, Robert

2016-01-01

Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the Shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a Shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. NASA is currently refining risk assessment estimates for the probability of bird strike to space launch vehicles. This paper presents an approach for analyzing the risks of bird strikes to space launch vehicles and presents an example. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts affect the risk due to bird strike. A summary of significant risk contributors is discussed.

Avian influenza virus wild bird surveillance in the Azov and Black Sea regions of Ukraine (2010-2011).

PubMed

Muzyka, Denys; Pantin-Jackwood, Mary; Spackman, Erica; Stegniy, Borys; Rula, Oleksandr; Shutchenko, Pavlo

2012-12-01

The Azov and Black Sea basins are part of the transcontinental wild bird migration routes from Northern Asia and Europe to the Mediterranean, Africa, and Southwest Asia. These regions constitute an area of transit, stops during migration, and nesting for many different bird species. From September 2010 to September 2011, a wild bird surveillance study was conducted in these regions to identify avian influenza viruses. Biological samples consisting of cloacal and tracheal swabs and fecal samples were collected from wild birds of different ecological groups, including waterfowl and sea- and land-based birds, in places of mass bird accumulations in Sivash Bay and the Utlyuksky and Molochniy estuaries. The sampling covered the following wild bird biological cycles: autumn migration, wintering, spring migration, nesting, and postnesting seasons. A total of 3634 samples were collected from 66 different species of birds. During the autumn migration, 19 hemagglutinating viruses were isolated, 14 of which were identified as low pathogenicity avian influenza (LPAI) virus subtypes H1N?, H3N8, H5N2, H7N?, H8N4, H10N7, and H11N8. From the wintering samples, 45 hemagglutinating viruses were isolated, 36 of which were identified as LPAI virus subtypes H1N1, H1N? H1N2, H4N?, H6N1, H7N3, H7N6, H7N7, H8N2, H9N2, H10N7, H10N4, H11N2, H12N2, and H15N7. Only three viruses were isolated during the spring migration, nesting, and postnesting seasons (serotypes H6, H13, and H16). The HA and NA genes were sequenced from the isolated H5 and N1 viruses, and the phylogenetic analysis revealed possible ecological connections between the Azov and Black Sea regions and Europe. The LPAI viruses were isolated mostly from mallard ducks, but also from shellducks, shovelers, teals, and white-fronted geese. The rest of the 14 hemagglutinating viruses isolated were identified as different serotypes of avian paramyxoviruses (APMV-1, APMV-4, APMV-6, and APMV-7). This information furthers our understanding of the ecology of avian influenza viruses in wild bird species.

Emergence of long distance bird migrations: a new model integrating global climate changes

NASA Astrophysics Data System (ADS)

Louchart, Antoine

2008-12-01

During modern birds history, climatic and environmental conditions have evolved on wide scales. In a continuously changing world, landbirds annual migrations emerged and developed. However, models accounting for the origins of these avian migrations were formulated with static ecogeographic perspectives. Here I reviewed Cenozoic paleoclimatic and paleontological data relative to the palearctic paleotropical long distance (LD) migration system. This led to propose a new model for the origin of LD migrations, the ‘shifting home’ model (SHM). It is based on a dynamic perspective of climate evolution and may apply to the origins of most modern migrations. Non-migrant tropical African bird taxa were present at European latitudes during most of the Cenozoic. Their distribution limits shifted progressively toward modern tropical latitudes during periods of global cooling and increasing seasonality. In parallel, decreasing winter temperatures in the western Palearctic drove shifts of population winter ranges toward the equator. I propose that this induced the emergence of most short distance migrations, and in turn LD migrations. This model reconciliates ecologically tropical ancestry of most LD migrants with predominant winter range shifts, in accordance with requirements for heritable homing. In addition, it is more parsimonious than other non-exclusive models. Greater intrinsic plasticity of winter ranges implied by the SHM is supported by recently observed impacts of the present global warming on migrating birds. This may induce particular threats to some LD migrants. The ancestral, breeding homes of LD migrants were not ‘northern’ or ‘southern’ but shifted across high and middle latitudes while migrations emerged through winter range shifts themselves.

Migration by soaring or flapping: numerical atmospheric simulations reveal that turbulence kinetic energy dictates bee-eater flight mode

PubMed Central

Sapir, Nir; Horvitz, Nir; Wikelski, Martin; Avissar, Roni; Mahrer, Yitzhak; Nathan, Ran

2011-01-01

Aerial migrants commonly face atmospheric dynamics that may affect their movement and behaviour. Specifically, bird flight mode has been suggested to depend on convective updraught availability and tailwind assistance. However, this has not been tested thus far since both bird tracks and meteorological conditions are difficult to measure in detail throughout extended migratory flyways. Here, we applied, to our knowledge, the first comprehensive numerical atmospheric simulations by mean of the Regional Atmospheric Modeling System (RAMS) to study how meteorological processes affect the flight behaviour of migrating birds. We followed European bee-eaters (Merops apiaster) over southern Israel using radio telemetry and contrasted bird flight mode (flapping, soaring–gliding or mixed flight) against explanatory meteorological variables estimated by RAMS simulations at a spatial grid resolution of 250 × 250 m2. We found that temperature and especially turbulence kinetic energy (TKE) determine bee-eater flight mode, whereas, unexpectedly, no effect of tailwind assistance was found. TKE during soaring–gliding was significantly higher and distinct from TKE during flapping. We propose that applying detailed atmospheric simulations over extended migratory flyways can elucidate the highly dynamic behaviour of air-borne organisms, help predict the abundance and distribution of migrating birds, and aid in mitigating hazardous implications of bird migration. PMID:21471116

Landbird migration along the Middle Rio Grande: Summary of banding data from spring and fall 1994

Treesearch

Wang Yong; Deborah M. Finch; Steve W. Cox

1995-01-01

Northbound and southbound movement along major waterways is characteristic of migratory birds nesting in North America. It is likely that river corridors are more important to migrating birds in arid parts of North America than in humid, more heavily vegetated areas (Wauer 1977). Although quantitative analyses of landbird migration along the Rio Grande corridor are not...

Isotope signatures in winter moulted feathers predict malaria prevalence in a breeding avian host.

PubMed

Yohannes, Elizabeth; Hansson, Bengt; Lee, Raymond W; Waldenström, Jonas; Westerdahl, Helena; Akesson, Mikael; Hasselquist, Dennis; Bensch, Staffan

2008-11-01

It is widely accepted that animal distribution and migration strategy might have co-evolved in relation to selection pressures exerted by parasites. Here, we first determined the prevalence and types of malaria blood parasites in a breeding population of great reed warblers Acrocephalus arundinaceus using PCR. Secondly, we tested for differences in individual feather stable isotope signatures (delta (13)C, delta (15)N, deltaD and delta (34)S) to investigate whether malaria infected and non-infected birds had occupied different areas in winter. We show that birds moulting in Afro-tropical habitats with significantly higher delta (13)C and delta (15)N but lower deltaD and delta(34)S values were more frequently infected with malaria parasites. Based on established patterns of isotopic distributions, our results indicate that moulting sites with higher incidence of malaria are generally drier and situated further to the north in West Africa than sites with lower incidence of malaria. Our findings are pertinent to the general hypothesis that animal distribution and particularly avian migration strategy might evolve in response to selection pressures exerted by parasites at different geographic scales. Tradeoffs between investment in energy demanding life history traits (e.g. migration and winter moult) and immune function are suggested to contribute to the particular choice of habitat during migration and at wintering sites.

Hippocampal neurogenesis and volume in migrating and wintering semipalmated sandpipers (Calidris pusilla)

PubMed Central

de Morais Magalhães, Nara Gyzely; Guerreiro Diniz, Daniel; Pereira Henrique, Ediely; Corrêa Pereira, Patrick Douglas; Matos Moraes, Isis Ananda; Damasceno de Melo, Mauro André; Sherry, David Francis; Wanderley Picanço Diniz, Cristovam

2017-01-01

Long distance migratory birds find their way by sensing and integrating information from a large number of cues in their environment. These cues are essential to navigate over thousands of kilometers and reach the same breeding, stopover, and wintering sites every year. The semipalmated sandpiper (Calidris pusilla) is a long-distance migrant that breeds in the arctic tundra of Canada and Alaska and winters on the northeast coast of South America. Its fall migration includes a 5,300-kilometer nonstop flight over the Atlantic Ocean. The avian hippocampus has been proposed to play a central role in the integration of multisensory spatial information for navigation. Hippocampal neurogenesis may contribute to hippocampal function and a variety of factors including cognitive activity, exercise, enrichment, diet and stress influence neurogenesis in the hippocampus. We quantified hippocampal neurogenesis and volume in adult migrating and wintering semipalmated sandpipers using stereological counts of doublecortin (DCX) immunolabeled immature neurons. We found that birds captured in the coastal region of Bragança, Brazil during the wintering period had more DCX positive neurons and larger volume in the hippocampus than individuals captured in the Bay of Fundy, Canada during fall migration. We also estimate the number of NeuN immunolabeled cells in migrating and wintering birds and found no significant differences between them. These findings suggest that, at this time window, neurogenesis just replaced neurons that might be lost during the transatlantic flight. Our findings also show that in active fall migrating birds, a lower level of adult hippocampal neurogenesis is associated with a smaller hippocampal formation. High levels of adult hippocampal neurogenesis and a larger hippocampal formation found in wintering birds may be late occurring effects of long distance migratory flight or the result of conditions the birds experienced while wintering. PMID:28591201

Hippocampal neurogenesis and volume in migrating and wintering semipalmated sandpipers (Calidris pusilla).

PubMed

de Morais Magalhães, Nara Gyzely; Guerreiro Diniz, Cristovam; Guerreiro Diniz, Daniel; Pereira Henrique, Ediely; Corrêa Pereira, Patrick Douglas; Matos Moraes, Isis Ananda; Damasceno de Melo, Mauro André; Sherry, David Francis; Wanderley Picanço Diniz, Cristovam

2017-01-01

Long distance migratory birds find their way by sensing and integrating information from a large number of cues in their environment. These cues are essential to navigate over thousands of kilometers and reach the same breeding, stopover, and wintering sites every year. The semipalmated sandpiper (Calidris pusilla) is a long-distance migrant that breeds in the arctic tundra of Canada and Alaska and winters on the northeast coast of South America. Its fall migration includes a 5,300-kilometer nonstop flight over the Atlantic Ocean. The avian hippocampus has been proposed to play a central role in the integration of multisensory spatial information for navigation. Hippocampal neurogenesis may contribute to hippocampal function and a variety of factors including cognitive activity, exercise, enrichment, diet and stress influence neurogenesis in the hippocampus. We quantified hippocampal neurogenesis and volume in adult migrating and wintering semipalmated sandpipers using stereological counts of doublecortin (DCX) immunolabeled immature neurons. We found that birds captured in the coastal region of Bragança, Brazil during the wintering period had more DCX positive neurons and larger volume in the hippocampus than individuals captured in the Bay of Fundy, Canada during fall migration. We also estimate the number of NeuN immunolabeled cells in migrating and wintering birds and found no significant differences between them. These findings suggest that, at this time window, neurogenesis just replaced neurons that might be lost during the transatlantic flight. Our findings also show that in active fall migrating birds, a lower level of adult hippocampal neurogenesis is associated with a smaller hippocampal formation. High levels of adult hippocampal neurogenesis and a larger hippocampal formation found in wintering birds may be late occurring effects of long distance migratory flight or the result of conditions the birds experienced while wintering.

Wintering ecology of adult North American ospreys

USGS Publications Warehouse

Washburn, Brian E.; Martell, Mark S.; Bierregaard, Richard O.; Henny, Charles J.; Dorr, Brian S.; Olexa, Thomas J.

2014-01-01

North American Ospreys (Pandion haliaetus) typically migrate long distances to their wintering grounds in the tropics. Beyond the general distribution of their wintering range (i.e., the Caribbean, South America, and Central America), very little is known about the wintering ecology of these birds. We used satellite telemetry to determine the duration of wintering period, to examine the characteristics of wintering areas used by Ospreys, and to quantify space use and activity patterns of wintering Ospreys. Adult Ospreys migrated to wintering sites and exhibited high wintering site fidelity among years. Overall, Ospreys wintered on river systems (50.6%) more than on lakes (19.0%), and use of coastal areas was (30.4%) intermediate. Ospreys remained on their wintering grounds for an average of 154 d for males and 167 d for females. Locations of wintering Ospreys obtained via GPS-capable satellite telemetry suggest these birds move infrequently and their movements are very localized (i.e., 2 and 1.4 km2, respectively. Overall, our findings suggest wintering adult North American Ospreys are very sedentary, demonstrating a pattern of limited daily movements and high fidelity to a few select locations (presumably roosts). We suggest this wintering strategy might be effective for reducing the risk of mortality and maximizing energy conservation.

Annual migratory patterns of long-billed curlews in the American west

USGS Publications Warehouse

Page, Gary W.; Warnock, Nils; Tibbitts, T. Lee; Jorgensen, Dennis; Hartman, C. Alex; Stenzel, Lynne E.

2014-01-01

Effective conservation of migratory species requires comprehensive knowledge of annual movement patterns. Such information is sparse for the Long-billed Curlew (Numenius americanus), a North American endemic shorebird of conservation concern. To test hypotheses about individual and area differences in migratory patterns across western North America, we tagged 29 curlews with satellite transmitters at breeding sites in Oregon, Nevada, and Montana. Transmissions from 28 birds for up to 4 years demonstrated that all wintered within the species’ known winter range, including 9 from Oregon tracked to agricultural areas of California’s Central Valley; 5 from Nevada tracked to the Central Valley, northern Gulf of California, or west coast of Baja California, Mexico; and 14 from Montana that wintered inland, from the Texas Panhandle south to the Mexican Plateau, or near the Gulf of Mexico. Montana breeders migrated east of the Rocky Mountains and traveled more than twice the distance of Oregon and Nevada breeders. Montana birds also stopped more often and longer during most passages. As a group, curlews arrived on their Oregon breeding grounds earlier than in Montana, while males preceded females in Montana and possibly Oregon. No consistent pattern emerged between sexes in departure from breeding areas, although within pairs males departed later than their mates. Individuals exhibited strong fidelity to breeding and wintering sites, and many birds showed a strong propensity for agricultural regions during winter. Our results underscore the importance of studying

Space-based Remote Sensing: A Tool for Studying Bird Migration Across Multiple Scales

NASA Technical Reports Server (NTRS)

Smith, James A.

2005-01-01

The study of bird migration on a global scale is one of the compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties. Space based technology offers new opportunities to shed understanding on the distribution and migration of organisms on the planet and their sensitivity to human disturbances and environmental changes. Our working hypothesis is that individual organism biophysical models of energy and water balance, driven by satellite measurements of spatio-temporal gradients in climate and habitat, will help us to explain the variability in avian species richness and distribution. Further, these models provide an ecological forecasting tool for science and application users to visualize the possible consequences of loss of wetlands, flooding, or other natural disasters such as hurricanes on avian biodiversity and bird migration.

Can variation in risk of nest predation explain altitudinal migration in tropical birds?

PubMed

Boyle, W Alice

2008-03-01

Migration is among the best studied of animal behaviors, yet few empirical studies have tested hypotheses explaining the ultimate causes of these cyclical annual movements. Fretwell's (1980) hypothesis predicts that if nest predation explains why many tropical birds migrate uphill to breed, then predation risk must be negatively associated with elevation. Data from 385 artificial nests spanning 2,740 m of elevation on the Atlantic slope of Costa Rica show an overall decline in predation with increasing elevation. However, nest predation risk was highest at intermediate elevations (500-650 m), not at lowest elevations. The proportion of nests depredated by different types of predators differed among elevations. These results imply that over half of the altitudinal migrant bird species in this region migrate to safer breeding areas than their non-breeding areas, suggesting that variation in nest predation risk could be an important benefit of uphill migrations of many species.

Post-breeding movements of Ancient Murrelet Synthliboramphus antiquus family groups, subsequent migration of adults and implications for management.

PubMed

Gaston, Anthony J; Hashimoto, Yuriko; Wilson, Laurie

2017-01-01

Increased shipping in British Columbia (BC) waters poses risks for marine birds from marine oil spills. Ancient Murrelets (Synthliboramphus antiquus), small marine diving birds of which half of the world's population breeds in BC, are especially susceptible to oiling immediately after departing from their breeding colonies, as their offspring are flightless, constraining their parents to remain with them. In 2014 we deployed geolocator loggers on Ancient Murrelets at four breeding colonies, two on the east and two on the west coast of Haida Gwaii to investigate patterns of post-breeding dispersal and subsequent migratory movements. Birds from east coast colonies moved south and east after leaving their colonies, remaining in Queen Charlotte Sound and adjacent waters for 4-6 weeks, whereas those from west coast colonies moved steadily north and west, so that they left BC waters earlier than those from east coast colonies. These movements were consistent with being driven by surface currents. In June, all birds moved rapidly to the eastern Aleutians, SE Bering Sea, and waters off Kamchatka, where they probably moulted. In August, most moved north, some passing through Bering Straits into the Chukchi Sea. In October-November some birds returned to waters off western N America (33%) and the remainder carried on westwards to waters off Japan, Korea and NE China. For the former group the movement to the Bering Sea in June constituted a moult migration and, as such, is the first described for an auk. Those birds wintering in Asia began moving east in February and arrived off BC in March, when observations at colonies show that burrow visits begin in Haida Gwaii. Our data suggest that, immediately after colony departure, birds from the east coast colonies (about half the population of Haida Gwaii) are at higher risk from potential oil spills in northern British Columbia waters than those breeding on the west coast.

Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

PubMed

Reperant, Leslie A; van de Bildt, Marco W G; van Amerongen, Geert; Buehler, Debbie M; Osterhaus, Albert D M E; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

2011-01-01

Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot (Calidris canutus islandica) displays migratory changes in captivity and was used as a model to assess the effect of high plasma concentration of corticosterone on HPAIV H5N1 infection. We inoculated knots during pre-migration (N = 6), fueling (N = 5), migration (N = 9) and post-migration periods (N = 6). Knots from all groups shed similar viral titers for up to 5 days post-inoculation (dpi), peaking at 1 to 3 dpi. Lesions of acute encephalitis, associated with virus replication in neurons, were seen in 1 to 2 knots per group, leading to neurological disease and death at 5 to 11 dpi. Therefore, the risk of HPAIV H5N1 infection in wild birds and of potential transmission between wild birds and poultry may be similar at different times of the year, irrespective of wild birds' migratory status. However, in knots inoculated during the migration period, viral shedding levels positively correlated with pre-inoculation plasma concentration of corticosterone. Of these, knots that did not become productively infected had lower plasma concentration of corticosterone. Conversely, elevated plasma concentration of corticosterone did not result in an increased probability to develop clinical disease. These results suggest that birds with elevated plasma concentration of corticosterone at the time of migration (ready to migrate) may be more susceptible to acquisition of infection and shed higher viral titers--before the onset of clinical disease--than birds with low concentration of corticosterone (not ready for take-off). Yet, they may not be more prone to the development of clinical disease. Therefore, assuming no effect of sub-clinical infection on the likelihood of migratory take-off, this may favor the spread of HPAIV H5N1 by migratory birds over long distances.

Forecasting spring from afar? Timing of migration and predictability of phenology along different migration routes of an avian herbivore.

PubMed

Kölzsch, Andrea; Bauer, Silke; de Boer, Rob; Griffin, Larry; Cabot, David; Exo, Klaus-Michael; van der Jeugd, Henk P; Nolet, Bart A

2015-01-01

Herbivorous birds are hypothesized to migrate in spring along a seasonal gradient of plant profitability towards their breeding grounds (green wave hypothesis). For Arctic breeding species in particular, following highly profitable food is important, so that they can replenish resources along the way and arrive in optimal body condition to start breeding early. We compared the timing of migratory movements of Arctic breeding geese on different flyways to examine whether flyways differed in the predictability of spring conditions at stopovers and whether this was reflected in the degree to which birds were following the green wave. Barnacle geese (Branta leucopsis) were tracked with solar GPS/ARGOS PTTs from their wintering grounds to breeding sites in Greenland (N = 7), Svalbard (N = 21) and the Barents Sea (N = 12). The numerous stopover sites of all birds were combined into a set of 16 general stopover regions. The predictability of climatic conditions along the flyways was calculated as the correlation and slope between onsets of spring at consecutive stopovers. These values differed between sites, mainly because of the presence or absence of ecological barriers. Goose arrival at stopovers was more closely tied to the local onset of spring when predictability was higher and when geese attempted breeding that year. All birds arrived at early stopovers after the onset of spring and arrived at the breeding grounds before the onset of spring, thus overtaking the green wave. This is in accordance with patterns expected for capital breeders: first, they must come into condition; at intermediate stopovers, arrival with the food quality peak is important to stay in condition, and at the breeding grounds, early arrival is favoured so that hatching of young can coincide with the peak of food quality. Our results suggest that a chain of correlations between climatic conditions at subsequent stopovers enables geese to closely track the green wave. However, the birds' precision of migratory timing seems uninfluenced by ecological barriers, indicating partly fixed migration schedules. These might become non-optimal due to climate warming and preclude accurate timing of long-distance migrants in the future. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Migration and the evolution of duetting in songbirds.

PubMed

Logue, David M; Hall, Michelle L

2014-05-07

Many groups of animals defend shared resources with coordinated signals. The best-studied of these signals are the vocal duets produced by mated pairs of birds. Duets are believed to be more common among tropical-breeding species, but a comprehensive test of this hypothesis is lacking, and the mechanisms that generate latitudinal patterns in duetting are not known. We used a stratified sample of 372 songbird species to conduct the first broad-scale, phylogenetically explicit analysis of duet evolution. We found that duetting evolves in association with the absence of migration, but not with sexual monochromatism or tropical breeding. We conclude that the evolution of migration exerts a major influence on the evolution of duetting. The perceived association between tropical breeding and duetting may be a by-product of the migration-duetting relationship. Migration reduces the average duration of partnerships, potentially reducing the benefits of cooperative behaviour, including duetting. Ultimately, the evolution of coordinated resource-defence signals in songbirds may be driven by ecological conditions that favour sedentary lifestyles and social stability.

The microbiome of neotropical ticks parasitizing on passerine migratory birds.

PubMed

Budachetri, Khemraj; Williams, Jaclyn; Mukherjee, Nabanita; Sellers, Michael; Moore, Frank; Karim, Shahid

2017-01-01

Seasonal migration of passerine birds between temperate North America and tropical Central and South America is an ecological phenomenon. Migration of birds has been associated with the introduction of ectoparasites like ticks or tick-borne pathogens across the avian migration routes. In this study, the microbial diversity was determined in the ticks and bird DNA samples using 454 pyrosequencing of bacterial 16S rRNA gene. Tick DNA samples showed the dominance of genera Lactococcus, Francisella, Raoultella, Wolbachia and Rickettsia across all the ticks, but birds DNA did not share common microbial diversity with ticks. Furthermore, "Candidatus Rickettsia amblyommii" infection in the 91 ticks collected off the songbirds was also quantified by qPCR assay. Interestingly, "Candidatus R. amblyommii" was tested positive in 24 ticks (26% infection), and infection varied from as low as three copies to thousands of copies, but bird blood samples showed no amplification. Our results provide evidence that songbirds serve as transport carrier for immature ticks, and less likely to be a reservoir for "Candidatus R. amblyommii". Copyright © 2016 Elsevier GmbH. All rights reserved.

Alaska at the Crossroads of Migration: Space Based Ornithology

NASA Technical Reports Server (NTRS)

Deppe, Jill; Wessels, Konrad; Smith, James A.

2007-01-01

Understanding bird migration on a global scale is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Revolutionary advances in remote sensing now provide us with near real-time measurements of atmospheric and land surface conditions at high spatial resolution over entire continents. We use spatially-explicit, individual based bird migration models driven by numerical weather prediction models of atmospheric conditions, dynamic habitat suitability maps derived from remotely sensed land surface conditions, biophysiological models, and biological field data to simulate migration routes, timing, energy budgets, and survival of individual birds and populations. Long-distance migratory birds travel annually between breeding grounds in Alaska and wintering grounds in Latin Amierica. Approximately 25% of these species are potential vectors of Avian Influenza. Alaska is at the crossroads of Asian and New World migratory flyways and is likely to be a point of introduction of Asian H5N1 AI into the western hemisphere. If/when an infected bird is detected, a pressing question will be where was this bird several days ago, and where is it likely to go after it was released from the survey site? Answers to such questions will increase effectiveness of AI surveillance and mitigation measures. From a conservation perspective, Alaska's diverse landscape provides breeding sites for many migrants, and climatic and land surface changes along migratory flyways in the western hemisphere may reduce bird survival and physical condition upon arrival at Alaskan breeding territories, success and migrant populations.

Response of birds to climatic variability; evidence from the western fringe of Europe

NASA Astrophysics Data System (ADS)

Donnelly, Alison; Cooney, Tom; Jennings, Eleanor; Buscardo, Erika; Jones, Mike

2009-05-01

Ireland’s geographic location on the western fringe of the European continent, together with its island status and impoverished avifauna, provides a unique opportunity to observe changes in bird migration and distribution patterns in response to changing climatic conditions. Spring temperatures have increased in western Europe over the past 30 years in line with reported global warming. These have been shown, at least in part, to be responsible for changes in the timing of life cycle events (phenology) of plants and animals. In order to investigate the response of bird species in Ireland to changes in temperature, we examined ornithological records of trans-Saharan migrants over the 31-year period 1969-1999. Analysis of the data revealed that two discrete climatic phenomena produced different responses in summer migrant bird species. Firstly, a number of long-distance migrants showed a significant trend towards earlier arrival. This trend was evident in some species and was found to be a response to increasing spring air temperature particularly in the month of March. Secondly, (1) a step change in the pattern of occurrences of non-breeding migrant bird species, and (2) an increase in the ringing data of migrant species were found to correlate with a step change in temperature in 1987-1988. These results indicate that, for migrant bird species, the impact of a sudden change in temperature can be as important as any long-term monotonic trend, and we suggest that the impact of step change events merits further investigation on a wider range of species and across a greater geographical range.

Navigation.

PubMed

Wiltschko, Roswitha

2017-07-01

Experiments with migrating birds displaced during autumn migration outside their normal migration corridor reveal two different navigational strategies: adult migrants compensate for the displacement, and head towards their traditional wintering areas, whereas young first-time migrants continue in their migratory direction. Young birds are guided to their still unknown goal by a genetically coded migration program that indicates duration and direction(s) of the migratory flight by controlling the amount of migratory restlessness and the compass course(s) with respect to the geomagnetic field and celestial rotation. Adult migrants that have already wintered and are familiar with the goal area approach the goal by true navigation, specifically heading towards it and changing their course correspondingly after displacement. During their first journey, young birds experience the distribution of potential navigational factors en route and in their winter home, which allows them to truly navigate on their next migrations. The navigational factors used appear to include magnetic intensity as a component in their multi-modal navigational 'map'; olfactory input is also involved, even if it is not yet entirely clear in what way. The mechanisms of migratory birds for true navigation over long distances appear to be in principle similar to those discussed for by homing pigeons.

Body fat influences departure from stopover sites in migratory birds: evidence from whole-island telemetry

PubMed Central

Goymann, Wolfgang; Spina, Fernando; Ferri, Andrea; Fusani, Leonida

2010-01-01

Migration remains one of the great mysteries of animal life. Small migratory birds rely on refuelling stopovers after crossing ecological barriers such as deserts or seas. Previous studies have suggested that fuel reserves may determine stopover duration but this hypothesis could not be tested because of methodological limitations. Here, we provide evidence that subcutaneous fat stores determine stopover duration by measuring the permanence of migratory garden warblers (Sylvia borin) on a small Mediterranean island during spring migration with telemetry methods. Garden warblers with large amounts of fat stores departed the island significantly sooner than lean birds. All except one fat bird left the island on the same evening after capture, with a mean total stopover estimate of 8.8 hours. In contrast, the mean estimated total stopover duration of lean birds was 41.3 hours. To our knowledge, this is the first study that measures the true minimum stopover duration of a songbird during migration. PMID:20164077

Seasonal diets of insectivorous birds using canopy gaps in a bottomland forest.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moorman, Christopher, E.; Bowen, Liessa, T.; Kilgo, John, C.

2007-07-01

ABSTRACT. Little is known about how insectivorous bird diets are influenced by arthropod availability and about how these relationships vary seasonally. We captured birds in forest-canopy gaps and adjacent mature forest during 2001 and 2002 at the Savannah River Site in Barnwell County, South Carolina, and flushed their crops to gather information about arthropods eaten during four periods: spring migration, breeding, postbreeding, and fall migration. Arthropod availability for foliage- and ground-gleaning birds was examined by leaf clipping and pitfall trapping. Coleopterans and Hemipterans were used by foliage- and ground-gleaners more than expected during all periods, whereas arthropods in the ordersmore » Araneae and Hymenoptera were used as, or less than, expected based on availability during all periods. Ground-gleaning birds used Homopterans and Lepidopterans in proportions higher than availability during all periods. Arthropod use by birds was consistent from spring through all migration, with no apparent seasonal shift in diet. Based on concurrent studies, heavily used orders of arthropods were equally abundant or slightly less abundant in canopy gaps than in the surrounding mature forest, but bird species were most frequently detected in gaps. Such results suggest that preferential feeding on arthropods by foliage-gleaning birds in p p habitats reduced arthropod densities or, alternatively, that bird use of gap and forest habitat was not determined y food resources. The abundance of arthropods across the stand may have allowed birds to remain in the densely vegetated gaps where thick cover provides protection from predators.« less

Long-term patterns of fruit production in five forest types of the South Carolina upper coastal plain

Treesearch

Cathryn H. Greenberg; Douglas J. Levey; Charles Kwit; John P. McCarty; Scott F. Pearson; Sarah Sargent; John Kilgo

2012-01-01

Fleshy fruit is a key food resource for many vertebrates and may be particularly important energy source to birds during fall migration and winter. Hence, land managers should know how fruit availability varies among forest types, seasons, and years. We quantified fleshy fruit abundance monthly for 9 years (1995–2003) in 56 0.1-ha plots in 5 forest types of South...

Migration Routes and Staging Areas of Trans-Saharan Turtle Doves Appraised from Light-Level Geolocators

PubMed Central

Eraud, Cyril; Rivière, Marcel; Lormée, Hervé; Fox, James W.; Ducamp, Jean-Jacques; Boutin, Jean-Marie

2013-01-01

The identification of migration routes, wintering grounds and stopover sites are crucial issues for the understanding of the Palearctic-African bird migration system as well as for the development of relevant conservation strategies for trans-Saharan migrants. Using miniaturized light-level geolocators we report a comprehensive and detailed year round track of a granivorous trans-Saharan migrant, the European Turtle Dove (Streptopelia turtur). From five recovered loggers, our data provide new insights on migratory journeys and winter destinations of Turtle Doves originating from a breeding population in Western France. Data confirm that Turtle Doves wintered in West Africa. The main wintering area encompassed Western Mali, the Inner Delta Niger and the Malian/Mauritanian border. Some individuals also extended their wintering ranges over North Guinea, North-West of Burkina Faso and the Ivory-Coast. Our results reveal that all individuals did not spend the winter period at a single location; some of them experienced a clear eastward shift of several hundred kilometres. We also found evidence for a loop migration pattern, with a post-breeding migration flyway lying west of the spring route. Finally, we found that on their way back to breeding grounds Turtle Doves needed to refuel after crossing the Sahara desert. Contrary to previous suggestions, our data reveal that birds used stopover sites for several weeks, presumably in Morocco and North Algeria. This later finding is a crucial issue for future conservation strategies because environmental conditions on these staging areas might play a pivotal role in population dynamics of this declining species. PMID:23544064

Nematode parasite diversity in birds: the role of host ecology, life history and migration.

PubMed

Leung, Tommy L F; Koprivnikar, Janet

2016-11-01

Previous studies have found that migratory birds generally have a more diverse array of pathogens such as parasites, as well as higher intensities of infection. However, it is not clear whether this is driven by the metabolic and physiological demands of migration, differential selection on host life-history traits or basic ecological differences between migratory and non-migratory species. Parasitic helminths can cause significant pathology in their hosts, and many are trophically transmitted such that host diet and habitat use play key roles in the acquisition of infections. Given the concurrent changes in avian habitats and migratory behaviour, it is critical to understand the degree to which host ecology influences their parasite communities. We examined nematode parasite diversity in 153 species of Anseriformes (water birds) and Accipitriformes (predatory birds) in relation to their migratory behaviour, diet, habitat use, geographic distribution and life history using previously published data. Overall, migrators, host species with wide geographic distributions and those utilizing multiple aquatic habitats had greater nematode richness (number of species), and birds with large clutches harboured more diverse nematode fauna with respect to number of superfamilies. Separate analyses for each host order found similar results related to distribution, habitat use and migration; however, herbivorous water birds played host to a less diverse nematode community compared to those that consume some animals. Birds using multiple aquatic habitats have a more diverse nematode fauna relative to primarily terrestrial species, likely because there is greater opportunity for contact with parasite infectious stages and/or consumption of infected hosts. As such, omnivorous and carnivorous birds using aquatic habitats may be more affected by environmental changes that alter their diet and range. Even though there were no overall differences in their ecology and life history compared with non-migrators, migratory bird species still harboured a more diverse array of nematodes, suggesting that this behaviour places unique demands on these hosts and warrants further study. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Animal tracking meets migration genomics: transcriptomic analysis of a partially migratory bird species.

PubMed

Franchini, Paolo; Irisarri, Iker; Fudickar, Adam; Schmidt, Andreas; Meyer, Axel; Wikelski, Martin; Partecke, Jesko

2017-06-01

Seasonal migration is a widespread phenomenon, which is found in many different lineages of animals. This spectacular behaviour allows animals to avoid seasonally adverse environmental conditions to exploit more favourable habitats. Migration has been intensively studied in birds, which display astonishing variation in migration strategies, thus providing a powerful system for studying the ecological and evolutionary processes that shape migratory behaviour. Despite intensive research, the genetic basis of migration remains largely unknown. Here, we used state-of-the-art radio-tracking technology to characterize the migratory behaviour of a partially migratory population of European blackbirds (Turdus merula) in southern Germany. We compared gene expression of resident and migrant individuals using high-throughput transcriptomics in blood samples. Analyses of sequence variation revealed a nonsignificant genetic structure between blackbirds differing by their migratory phenotype. We detected only four differentially expressed genes between migrants and residents, which might be associated with hyperphagia, moulting and enhanced DNA replication and transcription. The most pronounced changes in gene expression occurred between migratory birds depending on when, in relation to their date of departure, blood was collected. Overall, the differentially expressed genes detected in this analysis may play crucial roles in determining the decision to migrate, or in controlling the physiological processes required for the onset of migration. These results provide new insights into, and testable hypotheses for, the molecular mechanisms controlling the migratory phenotype and its underlying physiological mechanisms in blackbirds and other migratory bird species. © 2017 John Wiley & Sons Ltd.

Innovative Visualizations Shed Light on Avian Nocturnal Migration

PubMed Central

Farnsworth, Andrew; Aelterman, Bart; Alves, Jose A.; Azijn, Kevin; Bernstein, Garrett; Branco, Sérgio; Desmet, Peter; Dokter, Adriaan M.; Horton, Kyle; Kelling, Steve; Kelly, Jeffrey F.; Leijnse, Hidde; Rong, Jingjing; Sheldon, Daniel; Van den Broeck, Wouter; Van Den Meersche, Jan Klaas; Van Doren, Benjamin Mark; van Gasteren, Hans

2016-01-01

Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals’ life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human–wildlife conflicts, improvement of meteorological products, and public outreach, education, and engagement. PMID:27557096

Innovative Visualizations Shed Light on Avian Nocturnal Migration.

PubMed

Shamoun-Baranes, Judy; Farnsworth, Andrew; Aelterman, Bart; Alves, Jose A; Azijn, Kevin; Bernstein, Garrett; Branco, Sérgio; Desmet, Peter; Dokter, Adriaan M; Horton, Kyle; Kelling, Steve; Kelly, Jeffrey F; Leijnse, Hidde; Rong, Jingjing; Sheldon, Daniel; Van den Broeck, Wouter; Van Den Meersche, Jan Klaas; Van Doren, Benjamin Mark; van Gasteren, Hans

2016-01-01

Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals' life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human-wildlife conflicts, improvement of meteorological products, and public outreach, education, and engagement.

Flight response of slope-soaring birds to seasonal variation in thermal generation

Treesearch

Adam E. Duerr; Tricia A. Miller; Michael Lanzone; David Brandes; Jeff Cooper; Kieran O' Malley; Charles Maisonneuve; Junior A. Tremblay; Todd Katzner

2014-01-01

Animals respond to a variety of environmental cues, including weather conditions, when migrating. Understanding the relationship between weather and migration behaviour is vital to assessing time- and energy limitations of soaring birds. Different soaring modes have different efficiencies, are dependent upon different types of subsidized lift and are weather dependent...

Current selection for lower migratory activity will drive the evolution of residency in a migratory bird population.

PubMed

Pulido, Francisco; Berthold, Peter

2010-04-20

Global warming is impacting biodiversity by altering the distribution, abundance, and phenology of a wide range of animal and plant species. One of the best documented responses to recent climate change is alterations in the migratory behavior of birds, but the mechanisms underlying these phenotypic adjustments are largely unknown. This knowledge is still crucial to predict whether populations of migratory birds will adapt to a rapid increase in temperature. We monitored migratory behavior in a population of blackcaps (Sylvia atricapilla) to test for evolutionary responses to recent climate change. Using a common garden experiment in time and captive breeding we demonstrated a genetic reduction in migratory activity and evolutionary change in phenotypic plasticity of migration onset. An artificial selection experiment further revealed that residency will rapidly evolve in completely migratory bird populations if selection for shorter migration distance persists. Our findings suggest that current alterations of the environment are favoring birds wintering closer to the breeding grounds and that populations of migratory birds have strongly responded to these changes in selection. The reduction of migratory activity is probably an important evolutionary process in the adaptation of migratory birds to climate change, because it reduces migration costs and facilitates the rapid adjustment to the shifts in the timing of food availability during reproduction.

Spatial dynamics of bar-headed geese migration in the context of H5N1

USGS Publications Warehouse

Bourouiba, L.; Wu, Jianhong; Newman, S.; Takekawa, John Y.; Natdorj, T.; Batbayar, N.; Bishop, C.M.; Hawkes, L.A.; Butler, P.J.; Wikelski, M.

2010-01-01

Virulent outbreaks of highly pathogenic avian influenza (HPAI) since 2005 have raised the question about the roles of migratory and wild birds in the transmission of HPAI. Despite increased monitoring, the role of wild waterfowl as the primary source of the highly pathogenic H5N1 has not been clearly established. The impact of outbreaks of HPAI among species of wild birds which are already endangered can nevertheless have devastating consequences for the local and non-local ecology where migratory species are established. Understanding the entangled dynamics of migration and the disease dynamics will be key to prevention and control measures for humans, migratory birds and poultry. Here, we present a spatial dynamic model of seasonal migration derived from first principles and linking the local dynamics during migratory stopovers to the larger scale migratory routes. We discuss the effect of repeated epizootic at specific migratory stopovers for bar-headed geese (Anser indicus). We find that repeated deadly outbreaks of H5N1 on stopovers during the autumn migration of bar-headed geese could lead to a larger reduction in the size of the equilibrium bird population compared with that obtained after repeated outbreaks during the spring migration. However, the opposite is true during the first few years of transition to such an equilibrium. The age-maturation process of juvenile birds which are more susceptible to H5N1 reinforces this result.

Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae)

PubMed Central

2010-01-01

Background The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards. Results In this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake. Conclusions We found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake. PMID:20482793

Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae).

PubMed

Reyes, Michelle; Zandberg, Katrina; Desmawati, Iska; de Bellard, Maria E

2010-05-18

The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards. In this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake. We found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake.

Primordial germ cell-mediated transgenesis and genome editing in birds.

PubMed

Han, Jae Yong; Park, Young Hyun

2018-01-01

Transgenesis and genome editing in birds are based on a unique germline transmission system using primordial germ cells (PGCs), which is quite different from the mammalian transgenic and genome editing system. PGCs are progenitor cells of gametes that can deliver genetic information to the next generation. Since avian PGCs were first discovered in nineteenth century, there have been numerous efforts to reveal their origin, specification, and unique migration pattern, and to improve germline transmission efficiency. Recent advances in the isolation and in vitro culture of avian PGCs with genetic manipulation and genome editing tools enable the development of valuable avian models that were unavailable before. However, many challenges remain in the production of transgenic and genome-edited birds, including the precise control of germline transmission, introduction of exogenous genes, and genome editing in PGCs. Therefore, establishing reliable germline-competent PGCs and applying precise genome editing systems are critical current issues in the production of avian models. Here, we introduce a historical overview of avian PGCs and their application, including improved techniques and methodologies in the production of transgenic and genome-edited birds, and we discuss the future potential applications of transgenic and genome-edited birds to provide opportunities and benefits for humans.

Arthropod abundance and seasonal bird use of bottomland forest harvest gaps.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moorman, Christopher, E.; Bowen, Liessa T.; Kilgo, John, C.

2012-03-01

We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and fall migration). Foliage arthropod densities were greatest in the forest understory in all four seasons, but understory vegetation density was greatest in gaps. Foliage-gleaning bird abundance was positively associated with foliage-dwelling arthropods during the breeding (F = 18.5, P < 0.001) and post-breeding periods (F = 9.4,more » P = 0.004), and negatively associated with foliage-dwelling arthropods during fall migration (F = 5.4, P = 0.03). Relationships between birds and arthropods were inconsistent, but the arthropod prey base seemed to be least important during migratory periods. Conversely, bird captures were positively correlated with understory vegetation density during all four periods (P < 0.001). Our study suggests high bird abundance associated with canopy gaps during the non-breeding period resulted less from high arthropod food resource availability than from complex understory and midstory vegetation structure.« less

Projected changes in prevailing winds for transatlantic migratory birds under global warming.

PubMed

La Sorte, Frank A; Fink, Daniel

2017-03-01

A number of terrestrial bird species that breed in North America cross the Atlantic Ocean during autumn migration when travelling to their non-breeding grounds in the Caribbean or South America. When conducting oceanic crossings, migratory birds tend to associate with mild or supportive winds, whose speed and direction may change under global warming. The implications of these changes for transoceanic migratory bird populations have not been addressed. We used occurrence information from eBird (1950-2015) to estimate the geographical location of population centres at a daily temporal resolution across the annual cycle for 10 transatlantic migratory bird species. We used this information to estimate the location and timing of autumn migration within the transatlantic flyway. We estimated how prevailing winds are projected to change within the transatlantic flyway during this time using daily wind speed anomalies (1996-2005 and 2091-2100) from 29 Atmosphere-Ocean General Circulation Models implemented under CMIP5. Autumn transatlantic migrants have the potential to encounter strong westerly crosswinds early in their transatlantic journey at intermediate and especially high migration altitudes, strong headwinds at low and intermediate migration altitudes within the Caribbean that increase in strength as the season progresses, and weak tailwinds at intermediate and high migration altitudes east of the Caribbean. The CMIP5 simulations suggest that, during this century, the likelihood of autumn transatlantic migrants encountering strong westerly crosswinds will diminish. As global warming progresses, the need for species to compensate or drift under the influence of strong westerly crosswinds during the initial phase of their autumn transatlantic journey may be diminished. Existing strategies that promote headwind avoidance and tailwind assistance will likely remain valid. Thus, climate change may reduce time and energy requirements and the chance of mortality or vagrancy during a specific but likely critical portion of these species' autumn migration journey. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Endohelminths in Bird Hosts from Northern California and an Analysis of the Role of Life History Traits on Parasite Richness.

PubMed

Hannon, Emily R; Kinsella, John M; Calhoun, Dana M; Joseph, Maxwell B; Johnson, Pieter T J

2016-04-01

The life history characteristics of hosts often influence patterns of parasite infection either by affecting the likelihood of parasite exposure or the probability of infection after exposure. In birds, migratory behavior has been suggested to affect both the composition and abundance of parasites within a host, although whether migratory birds have more or fewer parasites is unclear. To help address these knowledge gaps, we collaborated with airports, animal rescue/rehabilitation centers, and hunter check stations in the San Francisco Bay Area of California to collect 57 raptors, egrets, herons, ducks, and other waterfowl for parasitological analysis. After dissections of the gastrointestinal tract of each host, we identified 64 taxa of parasites: 5 acanthocephalans, 24 nematodes, 8 cestodes, and 27 trematodes. We then used a generalized linear mixed model to determine how life history traits influenced parasite richness among bird hosts, while controlling for host phylogeny. Parasite richness was greater in birds that were migratory with larger clutch sizes and lower in birds that were herbivorous. The effects of clutch size and diet are consistent with previous studies and have been linked to immune function and parasite exposure, respectively, whereas the effect of migration supports the hypothesis of "migratory exposure" rather than that of "migratory escape."

Prevalence of West Nile virus in migratory birds during spring and fall migration

USGS Publications Warehouse

Dusek, Robert J.; McLean, R.G.; Kramer, L.D.; Ubico, S.R.; Dupuis, A.P.; Ebel, G.D.; Guptill, S.C.

2009-01-01

To investigate the role of migratory birds in the dissemination of West Nile virus (WNV), we measured the prevalence of infectious WNV and specific WNV neutralizing antibodies in birds, principally Passeriformes, during spring and fall migrations in the Atlantic and Mississippi flyways from 2001-2003. Blood samples were obtained from 13,403 birds, representing 133 species. Specific WNV neutralizing antibody was detected in 254 resident and migratory birds, representing 39 species, and was most commonly detected in northern cardinals (Cardinalis cardinalis) (9.8%, N = 762) and gray catbirds (Dumetella carolinensis) (3.2%,N = 3188). West Nile virus viremias were detected in 19 birds, including 8 gray catbirds, and only during the fall migratory period. These results provide additional evidence that migratory birds may have been a principal agent for the spread of WNV in North America and provide data on the occurrence of WNV in a variety of bird species. Copyright ?? 2009 by The American Society of Tropical Medicine and Hygiene.

Temperature-influenced energetics model for migrating waterfowl

USGS Publications Warehouse

Aagaard, Kevin; Thogmartin, Wayne E.; Lonsdorg, Eric V.

2018-01-01

Climate and weather affect avian migration by influencing when and where birds fly, the energy costs and risks of flight, and the ability to sense cues necessary for proper navigation. We review the literature of the physiology of avian migration and the influence of climate, specifically temperature, on avian migration dynamics. We use waterfowl as a model guild because of the ready availability of empirical physiological data and their enormous economic value, but our discussion and expectations are broadly generalizable to migratory birds in general. We detail potential consequences of an increasingly warm climate on avian migration, including the possibility of the cessation of migration by some populations and species. Our intent is to lay the groundwork for including temperature effects on energetic gains and losses of migratory birds with the expected consequences of increasing temperatures into a predictive modeling framework. To this end, we provide a simulation of migration progression exclusively focused on the influence of temperature on the physiological determinants of migration. This simulation produced comparable results to empirically derived and observed values for different migratory factors (e.g., body fat content, flight range, departure date). By merging knowledge from the arenas of avian physiology and migratory theory we have identified a clear need for research and have developed hypotheses for a path forward.

The Far East taiga forest: unrecognized inhospitable terrain for migrating Arctic-nesting waterbirds?

PubMed

Wang, Xin; Cao, Lei; Bysykatova, Inga; Xu, Zhenggang; Rozenfeld, Sonia; Jeong, Wooseog; Vangeluwe, Didier; Zhao, Yunlin; Xie, Tianhe; Yi, Kunpeng; Fox, Anthony David

2018-01-01

The degree of inhospitable terrain encountered by migrating birds can dramatically affect migration strategies and their evolution as well as influence the way we develop our contemporary flyway conservation responses to protect them. We used telemetry data from 44 tagged individuals of four large-bodied, Arctic breeding waterbird species (two geese, a swan and one crane species) to show for the first time that these birds fly non-stop over the Far East taiga forest, despite their differing ecologies and migration routes. This implies a lack of suitable taiga refuelling habitats for these long-distance migrants. These results underline the extreme importance of northeast China spring staging habitats and of Arctic areas prior to departure in autumn to enable birds to clear this inhospitable biome, confirming the need for adequate site safeguard to protect these populations throughout their annual cycle.

The Far East taiga forest: unrecognized inhospitable terrain for migrating Arctic-nesting waterbirds?

PubMed Central

Wang, Xin; Bysykatova, Inga; Xu, Zhenggang; Rozenfeld, Sonia; Jeong, Wooseog; Vangeluwe, Didier; Zhao, Yunlin; Xie, Tianhe; Yi, Kunpeng; Fox, Anthony David

2018-01-01

The degree of inhospitable terrain encountered by migrating birds can dramatically affect migration strategies and their evolution as well as influence the way we develop our contemporary flyway conservation responses to protect them. We used telemetry data from 44 tagged individuals of four large-bodied, Arctic breeding waterbird species (two geese, a swan and one crane species) to show for the first time that these birds fly non-stop over the Far East taiga forest, despite their differing ecologies and migration routes. This implies a lack of suitable taiga refuelling habitats for these long-distance migrants. These results underline the extreme importance of northeast China spring staging habitats and of Arctic areas prior to departure in autumn to enable birds to clear this inhospitable biome, confirming the need for adequate site safeguard to protect these populations throughout their annual cycle. PMID:29479493

Epidemic spread in coupled populations with seasonally varying migration rates

NASA Astrophysics Data System (ADS)

Muzyczyn, Adam; Shaw, Leah B.

2009-03-01

The H5N1 strain of avian influenza has spread worldwide, and this spread may be due to seasonal migration of birds and mixing of birds from different regions in the wintering grounds. We studied a multipatch model for avian influenza with seasonally varying migration rates. The bird population was divided into two spatially distinct patches, or subpopulations. Within each patch, the disease followed the SIR (susceptible-infected-recovered) model for epidemic spread. Migration rates were varied periodically, with a net flux toward the breeding grounds during the spring and towards the wintering grounds during the fall. The case of two symmetric patches reduced to single-patch SIR dynamics. However, asymmetry in the birth and contact rates in the breeding grounds and wintering grounds led to bifurcations to longer period orbits and chaotic dynamics. We studied the bifurcation structure of the model and the phase relationships between outbreaks in the two patches.

Assessing relationships between cattle egret migration and meteorology in the southwest Pacific: a review

NASA Astrophysics Data System (ADS)

Bridgman, H. A.; Maddock, M.; Geering, D. J.

The evolution of research into meteorological factors affecting the migration of the Cattle Egret (Ardeola ibis coromandus) in the southwestern Pacific region (Australia, New Zealand and the Tasman Sea) - from ground-based studies dependent on volunteer observers to a pilot satellite-tracking project - is reviewed and the results are related to the literature on bird migration. The predominant pattern is a seasonal migration from breeding colonies in southeast Queensland and northern New South Wales which takes place in stages along the east coastal plain under favourable meteorological conditions. Migration outward (southward) occurs in February through April and return to the breeding colonies occurs in October and November. Wintering destinations include Tasmania, southern Victoria and parts of New Zealand. Favourable meteorological conditions for migration southward include:moderate north to northwest airflow behind a high; light and variable winds in a high or col; and light and variable winds over New South Wales with moderate westerlies over Victoria and Tasmania. A satellite-tracking project helped to validate findings from the ground-based studies, provided additional information not otherwise obtainable, and demonstrated the potential of the technique to further clarify the relation between timing and staging of migration, and meteorology.

Perceptual Strategies of Pigeons to Detect a Rotational Centre—A Hint for Star Compass Learning?

PubMed Central

Helduser, Sascha; Mouritsen, Henrik; Güntürkün, Onur

2015-01-01

Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy. PMID:25807499

Flight responses by a migratory soaring raptor to changing meteorological conditions.

PubMed

Lanzone, Michael J; Miller, Tricia A; Turk, Philip; Brandes, David; Halverson, Casey; Maisonneuve, Charles; Tremblay, Junior; Cooper, Jeff; O'Malley, Kieran; Brooks, Robert P; Katzner, Todd

2012-10-23

Soaring birds that undertake long-distance migration should develop strategies to minimize the energetic costs of endurance flight. This is relevant because condition upon completion of migration has direct consequences for fecundity, fitness and thus, demography. Therefore, strong evolutionary pressures are expected for energy minimization tactics linked to weather and topography. Importantly, the minute-by-minute mechanisms birds use to subsidize migration in variable weather are largely unknown, in large part because of the technological limitations in studying detailed long-distance bird flight. Here, we show golden eagle (Aquila chrysaetos) migratory response to changing meteorological conditions as monitored by high-resolution telemetry. In contrast to expectations, responses to meteorological variability were stereotyped across the 10 individuals studied. Eagles reacted to increased wind speed by using more orographic lift and less thermal lift. Concomitantly, as use of thermals decreased, variation in flight speed and altitude also decreased. These results demonstrate how soaring migrant birds can minimize energetic expenditures, they show the context for avian decisions and choices of specific instantaneous flight mechanisms and they have important implications for design of bird-friendly wind energy.

Assessment of bird populations in a high quality savanna/woodland: a banding approach

USGS Publications Warehouse

Wilmore, Sandra L.; Glowacki, Gary A.; Grundel, Ralph

2005-01-01

During the course of this six year study, the fall migration capture rate declined significantly, suggesting that reduced productivity may have occurred in bird populations. There was a positive response during the spring migration to earlier spring wildfires, indicated by high capture rates in 2000 and 2002 that corresponded with fires affecting most of the bird banding net locations. For several common species found at the Miller Woods site, the ratio of juveniles to adults was compared to ratios at other banding stations in the north central U.S. Breeding site fidelity was documented for 20 species, all common breeders. Variation in capture rates among net locations demonstrated the role of the shrub layer within the savanna habitat mosaic during migration stopover.

Birds and Wetlands of Alaska. Alaska Sea Week Curriculum Series. Alaska Sea Grant Report 88-1.

ERIC Educational Resources Information Center

King, James G.; King, Mary Lou

This curriculum guide is the fourth (Series V) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. Twelve units contain 45 activities with worksheets that cover the following topics: (1) bird lists and field guides; (2) definitions of a bird; (3) parts of a bird; (4) bird watching; (5) bird migration; (6) wetland…

Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration.

PubMed

Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M

2017-11-14

Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration

NASA Astrophysics Data System (ADS)

Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E.; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M.

2017-12-01

Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

Migration and the evolution of duetting in songbirds

PubMed Central

Logue, David M.; Hall, Michelle L.

2014-01-01

Many groups of animals defend shared resources with coordinated signals. The best-studied of these signals are the vocal duets produced by mated pairs of birds. Duets are believed to be more common among tropical-breeding species, but a comprehensive test of this hypothesis is lacking, and the mechanisms that generate latitudinal patterns in duetting are not known. We used a stratified sample of 372 songbird species to conduct the first broad-scale, phylogenetically explicit analysis of duet evolution. We found that duetting evolves in association with the absence of migration, but not with sexual monochromatism or tropical breeding. We conclude that the evolution of migration exerts a major influence on the evolution of duetting. The perceived association between tropical breeding and duetting may be a by-product of the migration–duetting relationship. Migration reduces the average duration of partnerships, potentially reducing the benefits of cooperative behaviour, including duetting. Ultimately, the evolution of coordinated resource-defence signals in songbirds may be driven by ecological conditions that favour sedentary lifestyles and social stability. PMID:24619447

The potential of fruit trees to enhance converted habitats for migrating birds in southern Mexico

USGS Publications Warehouse

Foster, M.S.

2007-01-01

Migration routes used by Nearctic migrant birds can cover great distances; they also differ among species, within species, and between years and seasons. As a result, migration routes for an entire migratory avifauna can encompass broad geographic areas, making it impossible to protect continuous stretches of habitat sufficient to connect the wintering and breeding grounds for most species. Consequently, ways to enhance habitats converted for human use (i.e. for pasture, crop cultivation, human settlement) as stopover sites for migrants are especially important. Shelterbelts around pastures and fields, if planted with species targeted to support migrant (and resident) bird species that naturally occupy mature forest habitats and that are at least partially frugivorous, could be a powerful enhancement tool for such species, if the birds will enter the converted areas to feed. I tested this approach for Nearctic migrant birds during the spring migration through an area in Chiapas, Mexico. Mature forest tree species whose fruits are eaten by birds were surveyed. Based on life form, crop size and fruit characteristics, I selected three tree species for study: Cymbopetalum mayanum (Annonaceae), Bursera simaruba (Burseraceae) and Trophis racemosa (Moraceae). I compared the use of fruits of these species by migrants and residents in forest with their use of the fruits of isolated individuals of the same species in pasture and cropland. All three plant species were useful for enhancing converted habitats for forest-occupying spring migrants, although species differed in the degree to which they entered disturbed areas to feed on the fruits. These tree species could probably enhance habitats for migrants at sites throughout the natural geographic ranges of the plants; in other geographic areas for other target bird groups, other tree species might be more appropriate.

A birds-eye view of biological connectivity in mangrove systems

NASA Astrophysics Data System (ADS)

Buelow, Christina; Sheaves, Marcus

2015-01-01

Considerable advances in understanding of biological connectivity have flowed from studies of fish-facilitated connectivity within the coastal ecosystem mosaic. However, there are limits to the information that fish can provide on connectivity. Mangrove-bird communities have the potential to connect coastal habitats in different ways and at different scales than fish, so incorporation of these links into our models of coastal ecosystem mosaics affords the opportunity to greatly increase the breadth of our understanding. We review the habitat and foraging requirements of mangrove-bird functional groups to understand how bird use of mangroves facilitates biological connectivity in coastal ecosystem mosaics, and how that connectivity adds to the diversity and complexity of ecological processes in mangrove ecosystems. Avian biological connectivity is primarily characterized by foraging behavior and habitat/resource requirements. Therefore, the consequence of bird links for coastal ecosystem functioning largely depends on patterns of habitat use and foraging, and potentially influences nutrient cycling, top-down control and genetic information linkage. Habitats that experience concentrated bird guano deposition have high levels of nitrogen and phosphorus, placing particular importance on the consequences of avian nutrient translocation and subsidization for coastal ecosystem functioning. High mobility allows mangrove-bird communities to link mangrove forests to other mangrove, terrestrial and marine-pelagic systems. Therefore, the spatial scale of coastal connectivity facilitated by birds is substantially more extensive than fish-facilitated connectivity. In particular, migratory birds link habitats at regional, continental and inter-continental scales as they travel among seasonally available feeding areas from breeding grounds to non-breeding grounds; scales at which there are few fish equivalents. Knowledge of the nature and patterns of fish connectivity have contributed to shifting the initial, historical perception of mangrove-ecosystem functioning from that of a simple system based on nutrient and energy retention, to a view that includes fish-facilitated energy export. In a similar way, understanding the nature and implications of mangrove connectivity through bird movements and migrations affords new possibilities for revising our view of the extent of functional links between mangroves and other ecosystems.

Cross-seasonal patterns of avian influenza virus in breeding and wintering migratory birds: a flyway perspective

USGS Publications Warehouse

Hill, Nichola J.; Takekawa, John Y.; Cardona, Carol J.; Meixell, Brandt W.; Ackerman, Joshua T.; Runstadler, Jonathan A.; Boyce, Walter M.

2012-01-01

The spread of avian influenza viruses (AIV) in nature is intrinsically linked with the movements of wild birds. Wild birds are the reservoirs for the virus and their migration may facilitate the circulation of AIV between breeding and wintering areas. This cycle of dispersal has become widely accepted; however, there are few AIV studies that present cross-seasonal information. A flyway perspective is critical for understanding how wild birds contribute to the persistence of AIV over large spatial and temporal scales, with implications for how to focus surveillance efforts and identify risks to public health. This study characterized spatio-temporal infection patterns in 10,389 waterfowl at two important locations within the Pacific Flyway--breeding sites in Interior Alaska and wintering sites in California's Central Valley during 2007-2009. Among the dabbling ducks sampled, the northern shoveler (Anas clypeata) had the highest prevalence of AIV at both breeding (32.2%) and wintering (5.2%) locations. This is in contrast to surveillance studies conducted in other flyways that have identified the mallard (Anas platyrhynchos) and northern pintail (Anas acuta) as hosts with the highest prevalence. A higher diversity of AIV subtypes was apparent at wintering (n=42) compared with breeding sites (n=17), with evidence of mixed infections at both locations. Our study suggests that wintering sites may act as an important mixing bowl for transmission among waterfowl in a flyway, creating opportunities for the reassortment of the virus. Our findings shed light on how the dynamics of AIV infection of wild bird populations can vary between the two ends of a migratory flyway.

Space-Based Ornithology: On the Wings of Migration and Biophysics

NASA Technical Reports Server (NTRS)

Smith, James A.

2006-01-01

Understanding bird migration and avian biodiversity is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties. Public interest is high with concerns about avian flu, Katrina and its impacts, and the recent sightings of the ivory-billed woodpecker. Space based technology gives us new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. Together with the USGS and other agencies, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. In our work, we use individual organism biophysical models of energy and water balance and drive these models with satellite measurements of spatio-temporal gradients in climate and habitat. Dynamic state variable modeling provides an additional tool for studying bird migration across multiple scales and can be linked to our mechanistic models describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. We also build upon the canopy done by the Environmental Laboratory over the past few years.

Migration of radio-marked whooping cranes from the Aransas-wood buffalo population: Patterns of habitat use, behavior, and survival. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howe, M.A.

1989-01-01

Use of migration stopovers by radio-marked whooping cranes (Grus americana) between Aransas National Wildlife Refuge, Texas, and central Saskatchewan was studied in fall 1981-83 and spring 1983-84 as part of a cooperative program with the Canadian Wildlife Service. Twenty-seven cranes were monitored for one or several seasons, including nine radio-marked birds and others that associated with them. Whooping cranes showed variations in their use of migration habitats, feeding primarily in a variety of croplands and roosting primarily in palustrine wetlands. More than 40% of the roosting wetlands were smaller than 0.5 ha. Although heavily vegetated wetlands were generally not used,more » family groups appeared to select more heavily vegetated wetlands than nonfamilies. Juveniles allocated 25% more time to foraging than did parents. Parents increased their foraging rate and showed less alert behavior in spring migration. Dissociation of parents and young occurred late in spring migration and after arrival on the breeding grounds.« less

Fuelling decisions in migratory birds: geomagnetic cues override the seasonal effect.

PubMed

Kullberg, Cecilia; Henshaw, Ian; Jakobsson, Sven; Johansson, Patrik; Fransson, Thord

2007-09-07

Recent evaluations of both temporal and spatial precision in bird migration have called for external cues in addition to the inherited programme defining the migratory journey in terms of direction, distance and fuelling behaviour along the route. We used juvenile European robins (Erithacus rubecula) to study whether geomagnetic cues affect fuel deposition in a medium-distance migrant by simulating a migratory journey from southeast Sweden to the wintering area in southern Spain. In the late phase of the onset of autumn migration, robins exposed to the magnetic treatment attained a lower fuel load than control birds exposed to the ambient magnetic field of southeast Sweden. In contrast, robins captured in the early phase of the onset of autumn migration all showed low fuel deposition irrespective of experimental treatment. These results are, as expected, the inverse of what we have found in similar studies in a long-distance migrant, the thrush nightingale (Luscinia luscinia), indicating that the reaction in terms of fuelling behaviour to a simulated southward migration varies depending on the relevance for the species. Furthermore, we suggest that information from the geomagnetic field act as an important external cue overriding the seasonal effect on fuelling behaviour in migratory birds.

Water requirements and drinking rates of homing pigeons: A consideration for exposure risk of migratory birds.

PubMed

Perez, Cristina R; Moye, John K; Pritsos, Chris A

2017-09-01

Access to water along a bird's migratory flyway is essential during the vital process of migration. Because of the scarcity of water in some environments, there is potential for migratory birds to encounter and drink from contaminated bodies of water. Ingestion of contaminated water may cause injury and compromise flying ability, leading to a disruption of migration. To determine injury to birds from potential exposure, it is essential to know not only the concentration of a given contaminant in the water but also the quantity and rate of water consumption by the birds. Homing pigeons (Columba livia) were used in a series of experiments to determine differences in drinking behavior after various flights and after periods of resting. Results from the present study demonstrate that homing pigeons' water consumption is dramatically different when assessed according to activity, flight distance, and time elapsed after flight. This suggests that the drinking rates of birds during migration are extremely important and much greater than estimated using traditional exposure assessment procedures. Thus, exposure to contaminants via drinking water may be greatly underestimated, and the rate of water consumption should be considered when estimating potential exposure risk to avian species. Integr Environ Assess Manag 2017;13:870-876. © 2017 SETAC. © 2017 SETAC.

Canada Geese at the Hanford Site – Trends in Reproductive Success, Migration Patterns, and Contaminant Concentrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simmons, Mary Ann; Poston, Ted M.; Tiller, Brett L.

2010-05-25

Pacific Northwest National Laboratory (PNNL) has conducted several studies for the U.S. Department of Energy (DOE) to evaluate the status and condition of Canada geese on the Hanford Reach of the Columbia River. This report summarizes results of studies of Canada geese (Branta canadensis moffitti) at the Hanford Site dating back to the 1950s. Results include information on the nesting (reproductive) success of Canada geese using the Hanford Reach, review of the local and regional migration of this species using data from bird banding studies, and summary data describing monitoring and investigations of the accumulation of Hanford-derived and environmental contaminantsmore » by resident goose populations.« less

Corridor- and stopover-use of the Hawaiian goose (Branta sandvicensis), an intratropical altitudinal migrant

USGS Publications Warehouse

Leopold, Christina R.; Hess, Steven C.

2014-01-01

We outfitted six male Hawaiian geese, or nene (Branta sandvicensis), with 45-g solar-powered satellite transmitters and collected four location coordinates d−1 from 2010 to 2012. We used 6193 coordinates to characterize migration corridors, habitat preferences and temporal patterns of displacement for 16 migration events with Brownian bridge utilization distributions (BBUD). We used 1552 coordinates to characterize stopovers from 37 shorter-distance movement events with 25% BBUDs. Two subpopulations used a well-defined common migration corridor spanning a broad gradient of elevation. Use of native-dominated subalpine shrubland was 2.81 times more likely than the availability of this land-cover type. The nene differed from other tropical and temperate-zone migrant birds in that: (1) migration distance and the number of stopovers were unrelated (Mann–Whitney test W = 241, P < 0.006), and; (2) individual movements were not unidirectional suggesting that social interactions may be more important than refuelling en route; but like other species, nene made more direct migrations with fewer stopovers in return to breeding areas (0.58 ± 0.50) than in migration away from breeding areas (1.64 ± 0.48). Our findings, combined with the direction and timing of migration, which is opposite that of most other intratropical migrants, suggest fundamentally different drivers of altitudinal migration.

How Displaced Migratory Birds Could Use Volatile Atmospheric Compounds to Find Their Migratory Corridor: A Test Using a Particle Dispersion Model

PubMed Central

Safi, Kamran; Gagliardo, Anna; Wikelski, Martin; Kranstauber, Bart

2016-01-01

Olfaction represents an important sensory modality for navigation of both homing pigeons and wild birds. Experimental evidence in homing pigeons showed that airborne volatile compounds carried by the winds at the home area are learned in association with wind directions. When displaced, pigeons obtain information on the direction of their displacement using local odors at the release site. Recently, the role of olfactory cues in navigation has been reported also for wild birds during migration. However, the question whether wild birds develop an olfactory navigational map similar to that described in homing pigeons or, alternatively, exploit the distribution of volatile compounds in different manner for reaching the goal is still an open question. Using an interdisciplinary approach, we evaluate the possibilities of reconstructing spatio-temporally explicit aerosol dispersion at large spatial scales using the particle dispersion model FLEXPART. By combining atmospheric information with particle dispersion models, atmospheric scientists predict the dispersion of pollutants for example, after nuclear fallouts or volcanic eruptions or wildfires, or in retrospect reconstruct the origin of emissions such as aerosols. Using simple assumptions, we reconstructed the putative origin of aerosols traveling to the location of migrating birds. We use the model to test whether the putative odor plume could have originated from an important stopover site. If the migrating birds knew this site and the associated plume from previous journeys, the odor could contribute to the reorientation towards the migratory corridor, as suggested for the model scenario in displaced Lesser black-backed gulls migrating from Northern Europe into Africa. PMID:27799899

Contrasting extreme long-distance migration patterns in bar-tailed godwits Limosa lapponica

USGS Publications Warehouse

Battley, Phil F.; Warnock, Nils; Tibbitts, T. Lee; Gill, Robert E.; Piersma, Theunis; Hassell, Chris J.; Douglas, David C.; Mulcahy, Daniel M.; Gartrell, Brett D.; Schuckard, Rob; Melville, David S.; Riegen, Adrian C.

2012-01-01

Migrating birds make the longest non-stop endurance flights in the animal kingdom. Satellite technology is now providing direct evidence on the lengths and durations of these flights and associated staging episodes for individual birds. Using this technology, we compared the migration performance of two subspecies of bar-tailed godwit Limosa lapponica travelling between non-breeding grounds in New Zealand (subspecies baueri) and northwest Australia (subspecies menzbieri) and breeding grounds in Alaska and eastern Russia, respectively. Individuals of both subspecies made long, usually non-stop, flights from non-breeding grounds to coastal staging grounds in the Yellow Sea region of East Asia (average 10 060 ± SD 290 km for baueri and 5860 ± 240 km for menzbieri). After an average stay of 41.2 ± 4.8 d, baueri flew over the North Pacific Ocean before heading northeast to the Alaskan breeding grounds (6770 ± 800 km).Menzbieri staged for 38.4 ± 2.5 d, and flew over land and sea northeast to high arctic Russia (4170 ± 370 km). The post-breeding journey for baueri involved several weeks of staging in southwest Alaska followed by non-stop flights across the Pacific Ocean to New Zealand (11 690 km in a complete track) or stopovers on islands in the southwestern Pacific en route to New Zealand and eastern Australia. By contrast, menzbieri returned to Australia via stopovers in the New Siberian Islands, Russia, and back at the Yellow Sea; birds travelled on average 4510 ± 360 km from Russia to the Yellow Sea, staged there for 40.8 ± 5.6 d, and then flew another 5680–7180 km to Australia (10 820 ± 300 km in total). Overall, the entire migration of the single baueri godwit with a fully completed return track totalled 29 280 km and involved 20 d of major migratory flight over a round-trip journey of 174 d. The entire migrations of menzbieri averaged 21 940 ± 570 km, including 14 d of major migratory flights out of 154 d total. Godwits of both populations exhibit extreme flight performance, and bauerimakes the longest (southbound) and second-longest (northbound) non-stop migratory flights documented for any bird. Both subspecies essentially make single stops when moving between non-breeding and breeding sites in opposite hemispheres. This reinforces the critical importance of the intertidal habitats used by fuelling godwits in Australasia, the Yellow Sea, and Alaska.

Genetic differentiation among migrant and resident populations of the threatened Asian houbara bustard.

PubMed

Riou, Samuel; Combreau, Olivier; Judas, Jacky; Lawrence, Mark; Al Baidani, Mohamed Saleh; Pitra, Christian

2012-01-01

The Asian houbara bustard Chlamydotis macqueenii is a partial migrant of conservation concern found in deserts of central Asia and the Middle East. In the southern part of the species range, resident populations have been greatly fragmented and reduced by sustained human pressure. In the north, birds migrate from breeding grounds between West Kazakhstan and Mongolia to wintering areas in the Middle East and south central Asia. Extensive satellite tracking has shown substantial partitioning in migration routes and wintering grounds, suggesting a longitudinal barrier to present-day gene flow among migrants. In this context, we explored genetic population structure using 17 microsatellite loci and sampling 108 individuals across the range. We identified limited but significant overall differentiation (F(CT) = 0.045), which was overwhelmingly due to the differentiation of resident Arabian populations, particularly the one from Yemen, relative to the central Asian populations. Population structure within the central Asian group was not detectable with the exception of subtle differentiation of West Kazakh birds on the western flyway, relative to eastern populations. We interpret these patterns as evidence of recent common ancestry in Asia, coupled with a longitudinal barrier to present-day gene flow along the migratory divide, which has yet to translate into genetic divergence. These results provide key parameters for a coherent conservation strategy aimed at preserving genetic diversity and migration routes.

Corticosterone secretion patterns prior to spring and autumn migration differ in free-living barn swallows (Hirundo rustica L.).

PubMed

Raja-aho, Sari; Lehikoinen, Esa; Suorsa, Petri; Nikinmaa, Mikko; Vainio, Minna; Vosloo, Dalene; Eeva, Tapio

2013-11-01

Recent studies of long-distance migratory birds show that behavioural and physiological changes associated with predictable or unpredictable challenges during the annual cycle are distinctively regulated by hormones. Corticosterone is the primary energy regulating hormone in birds. Corticosterone levels are elevated during stresses but they are also modulated seasonally according to environmental conditions and life-history demands. We measured the baseline and stress-induced levels of corticosterone in the barn swallow (Hirundo rustica L.) just before spring and autumn migrations in South Africa and Finland, respectively. Barn swallows completing their pre-breeding moult had low body condition (residual body mass) and high baseline corticosterone levels in the wintering grounds. In contrast, baseline corticosterone levels in Finland were low and not related to residual mass. These data contradict the first prediction of the migration modulation hypothesis (MMH) by showing no association with baseline corticosterone levels and pre-migratory fuelling. Yet, the adrenocortical response to the capture and handling stress was notably blunted in South Africa compared to a strong response in Finland. Further, individuals that had started fuelling in Finland showed a reduced response to the handling stress. Taken together, elevated baseline corticosterone levels and high residual mass may blunt the adrenocortical response in long-distance migrants and aerial feeders such as the barn swallow. This observation lends support to the second prediction of the MMH.

Ghrelin affects stopover decisions and food intake in a long-distance migrant.

PubMed

Goymann, Wolfgang; Lupi, Sara; Kaiya, Hiroyuki; Cardinale, Massimiliano; Fusani, Leonida

2017-02-21

Billions of birds migrate long distances to either reach breeding areas or to spend the winter at more benign places. On migration, most passerines frequently stop over to rest and replenish their fuel reserves. To date, we know little regarding how they decide that they are ready to continue their journey. What physiological signals tell a bird's brain that its fuel reserves are sufficient to resume migration? A network of hormones regulates food intake and body mass in vertebrates, including the recently discovered peptide hormone, ghrelin. Here, we show that ghrelin reflects body condition and influences migratory behavior of wild birds. We measured ghrelin levels of wild garden warblers ( Sylvia borin ) captured at a stopover site. Further, we manipulated blood concentrations of ghrelin to test its effects on food intake and migratory restlessness. We found that acylated ghrelin concentrations of garden warblers with larger fat scores were higher than those of birds without fat stores. Further, injections of unacylated ghrelin decreased food intake and increased migratory restlessness. These results represent experimental evidence that appetite-regulating hormones control migratory behavior. Our study lays a milestone in migration physiology because it provides the missing link between ecologically dependent factors such as condition and timing of migration. In addition, it offers insights in the regulation of the hormonal system controlling food intake and energy stores in vertebrates, whose disruption causes eating disorders and obesity.

Determinants of spring migration departure decision in a bat.

PubMed

Dechmann, Dina K N; Wikelski, M; Ellis-Soto, D; Safi, K; O'Mara, M Teague

2017-09-01

Migratory decisions in birds are closely tied to environmental cues and fat stores, but it remains unknown if the same variables trigger bat migration. To learn more about the rare phenomenon of bat migration, we studied departure decisions of female common noctules ( Nyctalus noctula ) in southern Germany. We did not find the fattening period that modulates departure decisions in birds. Female noctules departed after a regular evening foraging session, uniformly heading northeast. As the day of year increased, migratory decisions were based on the interactions among wind speed, wind direction and air pressure. As the migration season progressed, bats were likely to migrate on nights with higher air pressure and faster tail winds in the direction of travel, and also show high probability of migration on low-pressure nights with slow head winds. Common noctules thus monitor complex environmental conditions to find the optimal migration night. © 2017 The Authors.

Multiple spring migration strategies in a population of Pacific Common Eiders

USGS Publications Warehouse

Petersen, M.R.

2009-01-01

Spring migration strategies vary within and among species. Examination of this variability extends our understanding of life histories and has implications for conservation. I used satellite transmitters to determine migration strategies and evaluate factors influencing the timing of spring migration of Pacific Common Eiders (Somateria mollissima v-nigrum) that nest along the western Beaufort Sea coast. Adult females were marked at nesting colonies in the summers of 2000, 2001, and 2003, and were followed throughout spring migration the following year. Each year approximately equal proportions of eiders used three distinct migration strategies varying in duration, staging locations (waters near the Chukotka Peninsula, Russia, and the Chukchi and Beaufort seas, Alaska), and arrival dates at the nesting areas. It is unlikely that differences in the timing of movements to stopover sites in the Chukchi and Beaufort seas were a result of responses to changes in weather, particularly wind direction. Ice distribution and melt/movement patterns vary substantially among staging areas and thus may affect risk of starvation and reproductive potential. Long-term (decadal) changes in climate may favor birds using one strategy during "warmer" and another during "colder" years. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

Migrating songbirds recalibrate their magnetic compass daily from twilight cues.

PubMed

Cochran, William W; Mouritsen, Henrik; Wikelski, Martin

2004-04-16

Night migratory songbirds can use stars, sun, geomagnetic field, and polarized light for orientation when tested in captivity. We studied the interaction of magnetic, stellar, and twilight orientation cues in free-flying songbirds. We exposed Catharus thrushes to eastward-turned magnetic fields during the twilight period before takeoff and then followed them for up to 1100 kilometers. Instead of heading north, experimental birds flew westward. On subsequent nights, the same individuals migrated northward again. We suggest that birds orient with a magnetic compass calibrated daily from twilight cues. This could explain how birds cross the magnetic equator and deal with declination.

Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa.

PubMed

Vansteelant, W M G; Kekkonen, J; Byholm, P

2017-05-31

Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. © 2017 The Authors.

Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa

PubMed Central

Kekkonen, J.; Byholm, P.

2017-01-01

Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. PMID:28539514

Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla.

PubMed

Carvalho-Paulo, Dario; de Morais Magalhães, Nara G; de Almeida Miranda, Diego; Diniz, Daniel G; Henrique, Ediely P; Moraes, Isis A M; Pereira, Patrick D C; de Melo, Mauro A D; de Lima, Camila M; de Oliveira, Marcus A; Guerreiro-Diniz, Cristovam; Sherry, David F; Diniz, Cristovam W P

2017-01-01

Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla , that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D) morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy ( n = 249 cells) with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period ( n = 250 cells). Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes may play different physiological roles during migration.

Long-Term Phenological Shifts in Raptor Migration and Climate

PubMed Central

Jaffré, Mikaël; Beaugrand, Grégory; Goberville, Éric; Jiguet, Frédéric; Kjellén, Nils; Troost, Gerard; Dubois, Philippe J.; Leprêtre, Alain; Luczak, Christophe

2013-01-01

Climate change is having a discernible effect on many biological and ecological processes. Among observed changes, modifications in bird phenology have been widely documented. However, most studies have interpreted phenological shifts as gradual biological adjustments in response to the alteration of the thermal regime. Here we analysed a long-term dataset (1980-2010) of short-distance migratory raptors in five European regions. We revealed that the responses of these birds to climate-induced changes in autumn temperatures are abrupt and synchronous at a continental scale. We found that when the temperatures increased, birds delayed their mean passage date of autumn migration. Such delay, in addition to an earlier spring migration, suggests that a significant warming may induce an extension of the breeding-area residence time of migratory raptors, which may eventually lead to residency. PMID:24223888

Thermo-orientation and the movement of feather-feeding lice on hosts.

PubMed

Harbison, Christopher W; Boughton, Rachel M

2014-08-01

Temperature variation on the host is known to influence ectoparasite distributions. Ectoparasites may also use temperature gradients between host regions when moving on the host; however, tests are rare. Feather-feeding wing lice (Phthiraptera: Ischnocera) spend the majority of their time on the flight feathers of their avian hosts where they insert their bodies between feather barbs to escape host preening. However, because wing lice feed on downy abdominal feathers, they must repeatedly migrate between the flight feathers and body regions of their hosts. We performed a series of experiments that tested thermo-orientation in wing lice and evaluated its potential use during louse migrations between host regions. We found that wing lice can rapidly and accurately locate nearby heat targets that approximate host temperatures (37 C), demonstrating a capacity for directed thermo-orientation. We next tested the preference of wing lice for temperatures found along migration routes between bird flight feathers and their body regions. Wing lice could distinguish between temperatures found within distinct bird regions, and lice that had recently fed preferred the cooler temperatures (32 C), similar to those within bird flight feathers where they typically reside. However, when starved for 18-20 hr, wing lice shifted their preferences toward temperatures typical of bird body regions where they feed (36 C), demonstrating an ability to use thermal cues when moving between bird regions. We discuss the use of thermal cues during louse migration and microhabitat selection, as well as other potential impacts of thermo-orientation on host-parasite interactions.

Timing and location of mortality of fledgling, subadult, and adult California Gulls

USGS Publications Warehouse

Pugesek, B.H.; Diem, K.L.

2008-01-01

We investigated patterns of mortality during post-breeding migrations of California Gulls (Larus californicus) nesting near Laramie, Wyoming, USA. We used 151 recoveries and 647 sightings of banded and patagially-marked gulls to compare ratios of mortalities to observations of live birds (1) during four time periods (early and late fall migration, winter, and spring migration), (2) at two locations (Pacific coast and inland), and (3) among three age-classes of gulls (fledglings, 1- and 2-year-olds, and breeding-age adults). Mortality rates were higher in inland areas (35%) than in coastal areas (15%) and were dependent on season within inland areas, but not in coastal areas. Mortality in inland areas during early fall (21%) was comparable with that in coastal areas (13%) but was higher during late fall (68 vs. 13%) and spring migration (46 vs. 17%). Both fledgling (71%) and adult (64%) gulls experienced high mortality rates during late fall migration, possibly because some gulls were too weak to make their way to the Pacific coast and became trapped by poor weather conditions. Adult gulls also experienced high mortality inland during spring migration; few subadults made the costly migration to and from the breeding area. Some adults also skipped breeding and remained in coastal areas during the breeding season.

Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems

PubMed Central

Lea, James S. E.; Wetherbee, Bradley M.; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L.; Mucientes, Gonzalo R.; Humphries, Nicolas E.; Harvey, Guy M.; Sims, David W.; Shivji, Mahmood S.

2015-01-01

Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks. PMID:26057337

Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems.

PubMed

Lea, James S E; Wetherbee, Bradley M; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L; Mucientes, Gonzalo R; Humphries, Nicolas E; Harvey, Guy M; Sims, David W; Shivji, Mahmood S

2015-06-09

Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems

NASA Astrophysics Data System (ADS)

Lea, James S. E.; Wetherbee, Bradley M.; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L.; Mucientes, Gonzalo R.; Humphries, Nicolas E.; Harvey, Guy M.; Sims, David W.; Shivji, Mahmood S.

2015-06-01

Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

Optic flow cues guide flight in birds.

PubMed

Bhagavatula, Partha S; Claudianos, Charles; Ibbotson, Michael R; Srinivasan, Mandyam V

2011-11-08

Although considerable effort has been devoted to investigating how birds migrate over large distances, surprisingly little is known about how they tackle so successfully the moment-to-moment challenges of rapid flight through cluttered environments [1]. It has been suggested that birds detect and avoid obstacles [2] and control landing maneuvers [3-5] by using cues derived from the image motion that is generated in the eyes during flight. Here we investigate the ability of budgerigars to fly through narrow passages in a collision-free manner, by filming their trajectories during flight in a corridor where the walls are decorated with various visual patterns. The results demonstrate, unequivocally and for the first time, that birds negotiate narrow gaps safely by balancing the speeds of image motion that are experienced by the two eyes and that the speed of flight is regulated by monitoring the speed of image motion that is experienced by the two eyes. These findings have close parallels with those previously reported for flying insects [6-13], suggesting that some principles of visual guidance may be shared by all diurnal, flying animals. Copyright © 2011 Elsevier Ltd. All rights reserved.

Habitat associations of migrating and overwintering grassland birds in southern Texas

USGS Publications Warehouse

Igl, L.D.; Ballard, B.M.

1999-01-01

We report on the habitat associations of 21 species of grassland birds overwintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of the total bird densities in grassland and shrub-grassland habitats, but much lower proportions in the habitats with more woody vegetation. Fewer grassland species were observed in grassland and woodland than in brushland, parkland, and shrub-grassland habitats. Grassland birds generally were found in higher densities in habitats that had woody canopy coverage of < 30%; densities of grassland birds were highest in shrub-grassland habitat and lowest in woodland habitat. Species that are grassland specialists on their breeding grounds tended to be more habitat specific during the nonbreeding season compared to shrub-grassland specialists, which were more general in their nonbreeding-habitat usage. Nonetheless, our data demonstrate that grassland birds occur in a variety of habitats during the nonbreeding season and seem to occupy a broader range of habitats than previously described.

Habitat associations of migrating and overwintering grassland birds in Southern Texas

USGS Publications Warehouse

Igl, Lawrence D.; Ballard, Bart M.

1999-01-01

We report on the habitat associations of 21 species of grassland birds overwintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of the total bird densities in grassland and shrub-grassland habitats, but much lower proportions in the habitats with more woody vegetation. Fewer grassland species were observed in grassland and woodland than in brushland, parkland, and shrub-grassland habitats. Grassland birds generally were found in higher densities in habitats that had woody canopy coverage of < 30%; densities of grassland birds were highest in shrub-grassland habitat and lowest in woodland habitat. Species that are grassland specialists on their breeding grounds tended to be more habitat specific during the nonbreeding season compared to shrub-grassland specialists, which were more general in their nonbreeding-habitat usage. Nonetheless, our data demonstrate that grassland birds occur in a variety of habitats during the nonbreeding season and seem to occupy a broader range of habitats than previously described.

New software methods in radar ornithology using WSR-88D weather data and potential application to monitoring effects of climate change on bird migration

USGS Publications Warehouse

Mead, Reginald; Paxton, John; Sojda, Richard S.; Swayne, David A.; Yang, Wanhong; Voinov, A.A.; Rizzoli, A.; Filatova, T.

2010-01-01

Radar ornithology has provided tools for studying the movement of birds, especially related to migration. Researchers have presented qualitative evidence suggesting that birds, or at least migration events, can be identified using large broad scale radars such as the WSR-88D used in the NEXRAD weather surveillance system. This is potentially a boon for ornithologists because such data cover a large portion of the United States, are constantly being produced, are freely available, and have been archived since the early 1990s. A major obstacle to this research, however, has been that identifying birds in NEXRAD data has required a trained technician to manually inspect a graphically rendered radar sweep. A single site completes one volume scan every five to ten minutes, producing over 52,000 volume scans in one year. This is an immense amount of data, and manual classification is infeasible. We have developed a system that identifies biological echoes using machine learning techniques. This approach begins with training data using scans that have been classified by experts, or uses bird data collected in the field. The data are preprocessed to ensure quality and to emphasize relevant features. A classifier is then trained using this data and cross validation is used to measure performance. We compared neural networks, naive Bayes, and k-nearest neighbor classifiers. Empirical evidence is provided showing that this system can achieve classification accuracies in the 80th to 90th percentile. We propose to apply these methods to studying bird migration phenology and how it is affected by climate variability and change over multiple temporal scales.

Predicting the global spread of H5N1 avian influenza

PubMed Central

Kilpatrick, A. Marm; Chmura, Aleksei A.; Gibbons, David W.; Fleischer, Robert C.; Marra, Peter P.; Daszak, Peter

2006-01-01

The spread of highly pathogenic H5N1 avian influenza into Asia, Europe, and Africa has resulted in enormous impacts on the poultry industry and presents an important threat to human health. The pathways by which the virus has and will spread between countries have been debated extensively, but have yet to be analyzed comprehensively and quantitatively. We integrated data on phylogenetic relationships of virus isolates, migratory bird movements, and trade in poultry and wild birds to determine the pathway for 52 individual introduction events into countries and predict future spread. We show that 9 of 21 of H5N1 introductions to countries in Asia were most likely through poultry, and 3 of 21 were most likely through migrating birds. In contrast, spread to most (20/23) countries in Europe was most likely through migratory birds. Spread in Africa was likely partly by poultry (2/8 introductions) and partly by migrating birds (3/8). Our analyses predict that H5N1 is more likely to be introduced into the Western Hemisphere through infected poultry and into the mainland United States by subsequent movement of migrating birds from neighboring countries, rather than from eastern Siberia. These results highlight the potential synergism between trade and wild animal movement in the emergence and pandemic spread of pathogens and demonstrate the value of predictive models for disease control. PMID:17158217

Why do some, but not all, tropical birds migrate? A comparative study of diet breadth and fruit preference

USGS Publications Warehouse

Boyle, W.A.; Conway, C.J.; Bronstein, Judith L.

2011-01-01

Annual migrations of birds profoundly influence terrestrial communities. However, few empirical studies examine why birds migrate, in part due to the difficulty of testing causal hypotheses in long-distance migration systems. Short-distance altitudinal migrations provide relatively tractable systems in which to test explanations for migration. Many past studies explain tropical altitudinal migration as a response to spatial and temporal variation in fruit availability. Yet this hypothesis fails to explain why some coexisting, closely-related frugivorous birds remain resident year-round. We take a mechanistic approach by proposing and evaluating two hypotheses (one based on competitive exclusion and the other based on differences in dietary specialization) to explain why some, but not all, tropical frugivores migrate. We tested predictions of these hypotheses by comparing diets, fruit preferences, and the relationships between diet and preference in closely-related pairs of migrant and resident species. Fecal samples and experimental choice trials revealed that sympatric migrants and residents differed in both their diets and fruit preferences. Migrants consumed a greater diversity of fruits and fewer arthropods than did their resident counterparts. Migrants also tended to have slightly stronger fruit preferences than residents. Most critically, diets of migrants more closely matched their preferences than did the diets of residents. These results suggest that migrants may be competitively superior foragers for fruit compared to residents (rather than vice versa), implying that current competitive interactions are unlikely to explain variation in migratory behavior among coexisting frugivores. We found some support for the dietary specialization hypothesis, propose refinements to the mechanism underlying this hypothesis, and discuss how dietary specialization might ultimately reflect past interspecific competition. We recommend that future studies quantify variation in nutritional content of tropical fruits, and determine whether frugivory is a consequence or a cause of migratory behaviour. ?? 2010 Springer Science+Business Media B.V.

Challenging a 15-year-old claim: The North Atlantic Oscillation index as a predictor of spring migration phenology of birds.

PubMed

Haest, Birgen; Hüppop, Ommo; Bairlein, Franz

2018-04-01

Many migrant bird species that breed in the Northern Hemisphere show advancement in spring arrival dates. The North Atlantic Oscillation (NAO) index is one of the climatic variables that have been most often investigated and shown to be correlated with these changes in spring arrival. Although the NAO is often claimed to be a good predictor or even to have a marked effect on interannual changes in spring migration phenology of Northern Hemisphere breeding birds, the results on relations between spring migration phenology and NAO show a large variety, ranging from no, over weak, to a strong association. Several factors, such as geographic location, migration phase, and the NAO index time window, have been suggested to partly explain these observed differences in association. A combination of a literature meta-analysis, and a meta-analysis and sliding time window analysis of a dataset of 23 short- and long-distance migrants from the constant-effort trapping garden at Helgoland, Germany, however, paints a completely different picture. We found a statistically significant overall effect size of the NAO on spring migration phenology (coefficient = -0.14, SE = 0.054), but this on average only explains 0%-6% of the variance in spring migration phenology across all species. As such, the value and biological meaning of the NAO as a general predictor or explanatory variable for climate change effects on migration phenology of birds, seems highly questionable. We found little to no definite support for previously suggested factors, such as geographic location, migration phenology phase, or the NAO time window, to explain the heterogeneity in correlation differences. We, however, did find compelling evidence that the lack of accounting for trends in both time series has led to strongly inflated (spurious) correlations in many studies (coefficient = -0.13, SE = 0.019). © 2017 John Wiley & Sons Ltd.

Conservation Status of North American Birds in the Face of Future Climate Change.

PubMed

Langham, Gary M; Schuetz, Justin G; Distler, Trisha; Soykan, Candan U; Wilsey, Chad

2015-01-01

Human-induced climate change is increasingly recognized as a fundamental driver of biological processes and patterns. Historic climate change is known to have caused shifts in the geographic ranges of many taxa and future climate change is expected to result in even greater redistributions of species. As a result, predicting the impact of climate change on future patterns of biodiversity will greatly aid conservation planning. Using the North American Breeding Bird Survey and Audubon Christmas Bird Count, two of the most comprehensive continental datasets of vertebrates in the world, and correlative distribution modeling, we assessed geographic range shifts for 588 North American bird species during both the breeding and non-breeding seasons under a range of future emission scenarios (SRES A2, A1B, B2) through the end of the century. Here we show that 314 species (53%) are projected to lose more than half of their current geographic range across three scenarios of climate change through the end of the century. For 126 species, loss occurs without concomitant range expansion; whereas for 188 species, loss is coupled with potential to colonize new replacement range. We found no strong associations between projected climate sensitivities and existing conservation prioritizations. Moreover, species responses were not clearly associated with habitat affinities, migration strategies, or climate change scenarios. Our results demonstrate the need to include climate sensitivity into current conservation planning and to develop adaptive management strategies that accommodate shrinking and shifting geographic ranges. The persistence of many North American birds will depend on their ability to colonize climatically suitable areas outside of current ranges and management actions that target climate adaptation.

Conservation Status of North American Birds in the Face of Future Climate Change

PubMed Central

Langham, Gary M.; Schuetz, Justin G.; Distler, Trisha; Soykan, Candan U.; Wilsey, Chad

2015-01-01

Human-induced climate change is increasingly recognized as a fundamental driver of biological processes and patterns. Historic climate change is known to have caused shifts in the geographic ranges of many taxa and future climate change is expected to result in even greater redistributions of species. As a result, predicting the impact of climate change on future patterns of biodiversity will greatly aid conservation planning. Using the North American Breeding Bird Survey and Audubon Christmas Bird Count, two of the most comprehensive continental datasets of vertebrates in the world, and correlative distribution modeling, we assessed geographic range shifts for 588 North American bird species during both the breeding and non-breeding seasons under a range of future emission scenarios (SRES A2, A1B, B2) through the end of the century. Here we show that 314 species (53%) are projected to lose more than half of their current geographic range across three scenarios of climate change through the end of the century. For 126 species, loss occurs without concomitant range expansion; whereas for 188 species, loss is coupled with potential to colonize new replacement range. We found no strong associations between projected climate sensitivities and existing conservation prioritizations. Moreover, species responses were not clearly associated with habitat affinities, migration strategies, or climate change scenarios. Our results demonstrate the need to include climate sensitivity into current conservation planning and to develop adaptive management strategies that accommodate shrinking and shifting geographic ranges. The persistence of many North American birds will depend on their ability to colonize climatically suitable areas outside of current ranges and management actions that target climate adaptation. PMID:26333202

Finding a Place to Live.

ERIC Educational Resources Information Center

NatureScope, 1985

1985-01-01

Provides background information and student activities on bird habitats, how birds have adapted to living in these habitats, and bird migration. Each activity includes an objective, recommended age level(s), subject area(s), list of materials needed, and procedures. Ready-to-copy student materials (puzzles and worksheets) are included. (JN)

Overseas seed dispersal by migratory birds.

PubMed

Viana, Duarte S; Gangoso, Laura; Bouten, Willem; Figuerola, Jordi

2016-01-13

Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. © 2016 The Author(s).

Overseas seed dispersal by migratory birds

PubMed Central

2016-01-01

Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. PMID:26740610

Not all songbirds calibrate their magnetic compass from twilight cues: a telemetry study.

PubMed

Chernetsov, Nikita; Kishkinev, Dmitry; Kosarev, Vladislav; Bolshakov, Casimir V

2011-08-01

Migratory birds are able to use the sun and associated polarised light patterns, stellar cues and the geomagnetic field for orientation. No general agreement has been reached regarding the hierarchy of orientation cues. Recent data from naturally migrating North American Catharus thrushes suggests that they calibrate geomagnetic information daily from twilight cues. Similar results have been shown in caged birds in a few studies but not confirmed in others. We report that free-flying European migrants, song thrushes Turdus philomelos, released after pre-exposure to a horizontally rotated magnetic field, do not recalibrate their magnetic compass from solar cues, but rather show a simple domination of either the magnetic or the stellar compass. We suggest that different songbird species possess different hierarchies of orientation cues, depending on the geographic and ecological challenges met by the migrants.

Nocturnally migrating songbirds drift when they can and compensate when they must.

PubMed

Horton, Kyle G; Van Doren, Benjamin M; Stepanian, Phillip M; Hochachka, Wesley M; Farnsworth, Andrew; Kelly, Jeffrey F

2016-02-16

The shortest possible migratory route for birds is not always the best route to travel. Substantial research effort has established that birds in captivity are capable of orienting toward the direction of an intended goal, but efforts to examine how free-living birds use navigational information under conditions that potentially make direct flight toward that goal inefficient have been limited in spatiotemporal scales and in the number of individuals observed because of logistical and technological limitations. Using novel and recently developed techniques for analysis of Doppler polarimetric weather surveillance radar data, we examined two impediments for nocturnally migrating songbirds in eastern North America following shortest-distance routes: crosswinds and oceans. We found that migrants in flight often drifted sideways on crosswinds, but most strongly compensated for drift when near the Atlantic coast. Coastal migrants' tendency to compensate for wind drift also increased through the night, while no strong temporal differences were observed at inland sites. Such behaviors suggest that birds migrate in an adaptive way to conserve energy by assessing while airborne the degree to which they must compensate for wind drift.

Nocturnally migrating songbirds drift when they can and compensate when they must

PubMed Central

Horton, Kyle G.; Van Doren, Benjamin M.; Stepanian, Phillip M.; Hochachka, Wesley M.; Farnsworth, Andrew; Kelly, Jeffrey F.

2016-01-01

The shortest possible migratory route for birds is not always the best route to travel. Substantial research effort has established that birds in captivity are capable of orienting toward the direction of an intended goal, but efforts to examine how free-living birds use navigational information under conditions that potentially make direct flight toward that goal inefficient have been limited in spatiotemporal scales and in the number of individuals observed because of logistical and technological limitations. Using novel and recently developed techniques for analysis of Doppler polarimetric weather surveillance radar data, we examined two impediments for nocturnally migrating songbirds in eastern North America following shortest-distance routes: crosswinds and oceans. We found that migrants in flight often drifted sideways on crosswinds, but most strongly compensated for drift when near the Atlantic coast. Coastal migrants’ tendency to compensate for wind drift also increased through the night, while no strong temporal differences were observed at inland sites. Such behaviors suggest that birds migrate in an adaptive way to conserve energy by assessing while airborne the degree to which they must compensate for wind drift. PMID:26879152

Animals and How They Live.

ERIC Educational Resources Information Center

National Audubon Society, New York, NY.

This set of teaching aids consists of 14 Audubon Nature Bulletins, providing teachers and students with informational reading on animals. The bulletin titles are as follows: Birds: Their Adaptations to Ways of Life; Our Friends the Hawks; Mysteries of Bird Migration; Bird Nests; Camouflage in the Animal World; Snakes; Turtles; Frogs and Toads;…

Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

USGS Publications Warehouse

Coates, Peter S.; Casazza, Michael L.; Halstead, Brian J.; Fleskes, Joseph P.; Laughlin, James A.

2011-01-01

Radar systems designed to detect avian activity at airfields are useful in understanding factors that influence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfield was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was first explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24-hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coefficients) averaged across models and a relatively simple calculation for safety officers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fit. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refine these inference models and improve our understanding of factors that influence avian activity, which is necessary to inform management decisions aimed at reducing risk of bird strikes.

Demographic outcomes of diverse migration strategies assessed in a metapopulation of tundra swans.

PubMed

Ely, Craig R; Meixell, Brandt W

2016-01-01

Migration is a prominent aspect of the life history of many avian species, but the demographic consequences of variable migration strategies have only infrequently been investigated, and rarely when using modern technological and analytical methods for assessing survival, movement patterns, and long-term productivity in the context of life history theory. We monitored the fates of 50 satellite-implanted tundra swans (Cygnus columbianus) over 4 years from five disparate breeding areas in Alaska, and used known-fate analyses to estimate monthly survival probability relative to migration distance, breeding area, migratory flyway, breeding status, and age. We specifically tested whether migratory birds face a trade-off, whereby long-distance migrants realize higher survival rates at the cost of lower productivity because of reduced time on breeding areas relative to birds that migrate shorter distances and spend more time on breeding areas. Annual migration distances varied significantly among breeding areas (1020 to 12720 km), and were strongly negatively correlated with time spent on breeding areas (r = -0.986). Estimates of annual survival probability varied by wintering area (Pacific coast, Alaska Peninsula, and Eastern seaboard) and ranged from 0.79 (95%CI: 0.70-0.88) to 1.0, depending on criteria used to discern mortalities from radio failures. We did not find evidence for a linear relationship between migration distance and survival as swans from the breeding areas with the shortest and longest migration distances had the highest survival probabilities. Survival was lower in the first year post-marking than in subsequent years, but there was not support for seasonal differences in survival. Productivity varied among breeding populations and was generally inversely correlated to survival, but not migration distance or time spent on breeding areas. Tundra swans conformed to a major tenet of life history theory, as populations with the highest survival generally had the lowest productivity. The lack of a uniform relationship between time spent on breeding areas and productivity, or time spent on wintering areas and survival, indicates that factors other than temporal investment dictate demographic outcomes in this species. The tremendous diversity of migration strategies we identify in Alaskan tundra swans, without clear impacts on survival, underscores the ability of this species to adapt to different environments and climatic regimes.

Delineation of Tundra Swan Cygnus c. columbianus populations in North America: geographic boundaries and interchange

USGS Publications Warehouse

Ely, Craig R.; Sladen, William J. L.; Wilson, Heather M.; Savage, Susan E.; Sowl, Kristine M.; Henry, Bill; Schwitters, Mike; Snowden, James

2014-01-01

North American Tundra Swans Cygnus c. columbianus are composed of two wellrecognised populations: an Eastern Population (EP) that breeds across northern Canada and north of the Brooks Range in Alaska, which migrates to the eastern seaboard of the United States, and a Western Population (WP) that breeds in coastal regions of Alaska south of the Brooks Range and migrates to western North America. We present results of a recent major ringing effort from across the breeding range in Alaska to provide a better definition of the geographic extent of the migratory divide in Alaska. We also reassess the staging and winter distributions of these populations based on locations of birds tracked using satellite transmitters, and recent recoveries and sightings of neck-collared birds. Summer sympatry of EP and WP Tundra Swans is very limited, and largely confined to a small area in northwest Alaska. Autumn migration pathways of EP and WP Tundra swans abut in southwest Saskatchewan, a region where migrating WP birds turn west, and EP birds deviate abruptly eastward. Overall, from 1989 to 2013 inclusive, 2.6% of recoveries or resightings reported to the USGS Bird Banding Laboratory were of birds that moved from the domain of the population in which they were initially captured to within the range of the other population; a proportion roughly comparable to the results of Limpert et al. (1991) for years before 1990. Of the 70 cross-boundary movements reported since 1989, 39% were of birds marked on breeding areas and 61% were of birds marked on wintering areas. Dispersing swans (i.e. those that made crossboundary movements) did not differ with respect to age or sex from those that did not move between populations. The Brooks Range in northern Alaska effectively separates the two populations within Alaska, but climate-induced changes in tundra breeding habitats and losses of wetlands on staging areas may alter the distribution for both of these populations.

Flying with the wind: scale dependency of speed and direction measurements in modelling wind support in avian flight.

PubMed

Safi, Kamran; Kranstauber, Bart; Weinzierl, Rolf; Griffin, Larry; Rees, Eileen C; Cabot, David; Cruz, Sebastian; Proaño, Carolina; Takekawa, John Y; Newman, Scott H; Waldenström, Jonas; Bengtsson, Daniel; Kays, Roland; Wikelski, Martin; Bohrer, Gil

2013-01-01

Understanding how environmental conditions, especially wind, influence birds' flight speeds is a prerequisite for understanding many important aspects of bird flight, including optimal migration strategies, navigation, and compensation for wind drift. Recent developments in tracking technology and the increased availability of data on large-scale weather patterns have made it possible to use path annotation to link the location of animals to environmental conditions such as wind speed and direction. However, there are various measures available for describing not only wind conditions but also the bird's flight direction and ground speed, and it is unclear which is best for determining the amount of wind support (the length of the wind vector in a bird's flight direction) and the influence of cross-winds (the length of the wind vector perpendicular to a bird's direction) throughout a bird's journey. We compared relationships between cross-wind, wind support and bird movements, using path annotation derived from two different global weather reanalysis datasets and three different measures of direction and speed calculation for 288 individuals of nine bird species. Wind was a strong predictor of bird ground speed, explaining 10-66% of the variance, depending on species. Models using data from different weather sources gave qualitatively similar results; however, determining flight direction and speed from successive locations, even at short (15 min intervals), was inferior to using instantaneous GPS-based measures of speed and direction. Use of successive location data significantly underestimated the birds' ground and airspeed, and also resulted in mistaken associations between cross-winds, wind support, and their interactive effects, in relation to the birds' onward flight. Wind has strong effects on bird flight, and combining GPS technology with path annotation of weather variables allows us to quantify these effects for understanding flight behaviour. The potentially strong influence of scaling effects must be considered and implemented in developing sampling regimes and data analysis.

From warm to cold: migration of Adélie penguins within Cape Bird, Ross Island

NASA Astrophysics Data System (ADS)

Nie, Yaguang; Sun, Liguang; Liu, Xiaodong; Emslie, Steven D.

2015-06-01

Due to their sensitivity to environmental change, penguins in Antarctica are widely used as bio-indicators in paleoclimatic research. On the basis of bio-element assemblages identified in four ornithogenic sediment profiles, we reconstructed the historical penguin population change at Cape Bird, Ross Island, for the past 1600 years. Clear succession of penguin population peaks were observed in different profiles at about 1400 AD, which suggested a high probability of migration within this region. The succession was most obviously marked by a sand layer lasting from 1400 to 1900 AD in one of the analyzed profiles. Multiple physical/chemical parameters indicated this sand layer was not formed in a lacustrine environment, but was marine-derived. Both isostatic subsidence and frequent storms under the colder climatic condition of the Little Ice Age were presumed to have caused the abandonment of the colonies, and we believe the penguins migrated from the coastal area of mid Cape Bird northward and to higher ground as recorded in the other sediment profiles. This migration was an ecological response to global climate change and possible subsequent geological effects in Antarctica.

Geolocators reveal migration and pre-breeding behaviour of the critically endangered Balearic Shearwater Puffinus mauretanicus.

PubMed

Guilford, Tim; Wynn, Russell; McMinn, Miguel; Rodríguez, Ana; Fayet, Annette; Maurice, Lou; Jones, Alice; Meier, Rhiannon

2012-01-01

Using combined miniature archival light and salt-water immersion loggers, we characterise the year-round individual at-sea movements of Europe's only critically endangered seabird, the Balearic shearwater Puffinus mauretanicus, for the first time. Focusing on the non-breeding period, we show that all of the 26 breeding birds tracked from their breeding site on Mallorca in the Mediterranean Sea successfully made a 2-4 month migration into the Atlantic Ocean, where they utilised well-defined core areas off Portuguese and French coasts. As well as identifying high-risk areas in the Atlantic, our results confirm that breeding birds spend most of the year concentrated around productive waters of the Iberian shelf in the western Mediterranean. Migration phenology appeared largely unrelated to the subsequent (distinctly synchronous) breeding attempt, suggesting that any carry-over effects were compensated for during a long pre-laying period spent over winter in the Mediterranean. Using the light and salt-water immersion data alone we were also able to characterise the pattern of pre-laying visits to the colony in considerable detail, demonstrating that breeding pairs appear to coordinate their over-day visits using a high frequency of night-time visits throughout the winter. Our study shows that geolocation technology is a valuable tool for assessing the spatial distribution of risks to this critically endangered species, and also provides a low-impact method for remotely observing the detailed behaviour of seabird species that may be sensitive to disturbance from traditional study methods.

The first hop: Use of Beaufort Sea deltas by hatch-year semipalmated sandpipers

USGS Publications Warehouse

Churchwell, Roy T.; Kendall, Steve J.; Brown, Stephen C.; Blanchard, Arny L.; Hollmen, Tuula E.; Powell, Abby

2018-01-01

River deltas along Alaska’s Beaufort Sea coast are used by hatch-year semipalmated sandpipers (Calidris pusilla) after leaving their terrestrial natal sites, but the drivers of their use of these stopover sites on the first “hop” of fall migration are unknown. We quantified sandpiper temporal distribution and abundance as related to food resources at three river deltas during the beginning of their fall migration (post-breeding period) to compare the habitat quality among these deltas. We conducted population counts, sampled invertebrates, and captured birds to collect blood samples from individuals for triglyceride and stable isotope analyses to determine fattening rates and diet. Patterns of sandpiper and invertebrate abundance were complex and varied among deltas and within seasons. River deltas were used by sandpipers from late July to late August, and peak sandpiper counts ranged from 1000 to 4000 individuals, of which 98% were hatch-year semipalmated sandpipers. Isotopic signatures from blood plasma samples indicated that birds switched from a diet of upland tundra to delta invertebrate taxa as the migration season progressed, suggesting a dependence on delta invertebrates. Despite differences in diet among deltas, we found no differences in fattening rates of juvenile sandpipers as indicated by triglyceride levels. The number of sandpipers was positively associated with abundance of Amphipoda and Oligochaeta at the Jago and Okpilak-Hulahula deltas; an isotopic mixing model indicated that sandpipers consumed Amphipoda and Oligochaeta at Jago, mostly Chironomidae at Okpilak-Hulahula and Spionidae at Canning. Regardless of the difference in sandpiper diets at the Beaufort Sea deltas, their similar fattening rates throughout the season indicate that all of these stopover sites provide a critical food resource for hatch-year sandpipers beginning their first migration.

International importance of the eastern Chukchi Sea as a staging area for migrating king eiders

USGS Publications Warehouse

Oppel, S.; Dickson, D.L.; Powell, A.N.

2009-01-01

The evaluation of habitats used by arctic birds on migration is crucial for their conservation. We explored the importance of the eastern Chukchi Sea (ECS) as a staging area for king eiders (Somateria spectabilis) migrating between breeding areas in Siberia and western North America and wintering areas in the Bering Sea. We tracked 190 king eiders with satellite transmitters between 1997 and 2007. In late summer, 74% of satellite-tracked king eiders migrating south staged in the ECS for 13 ?? 13 (SD) days between late June and early November. During spring migration, king eiders staged in the ECS between mid-April and early June for 21 ?? 10 days. All instrumented birds migrating to breeding grounds in western North America (n = 62), and 6 of 11 males migrating to breeding grounds in Siberia, used this area for at least 1 week during spring migration. The importance of this staging area renders it possible that industrial development could adversely affect king eider populations in both Siberia and North America. ?? 2009 US Government.

Negotiating an ecological barrier: crossing the Sahara in relation to winds by common swifts

PubMed Central

2016-01-01

The Sahara Desert is one of the largest land-based barriers on the Earth, crossed twice each year by billions of birds on migration. Here we investigate how common swifts migrating between breeding sites in Sweden and wintering areas in sub-Saharan Africa perform the desert crossing with respect to route choice, winds, timing and speed of migration by analysing 72 geolocator tracks recording migration. The swifts cross western Sahara on a broad front in autumn, while in spring they seem to use three alternative routes across the Sahara, a western, a central and an eastern route across the Arabian Peninsula, with most birds using the western route. The swifts show slower migration and travel speeds, and make longer detours with more stops in autumn compared with spring. In spring, the stopover period in West Africa coincided with mostly favourable winds, but birds remained in the area, suggesting fuelling. The western route provided more tailwind assistance compared with the central route for our tracked swifts in spring, but not in autumn. The ultimate explanation for the evolution of a preferred western route is presumably a combination of matching rich foraging conditions (swarming insects) and favourable winds enabling fast spring migration. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528783

Outlier analyses to test for local adaptation to breeding grounds in a migratory arctic seabird.

PubMed

Tigano, Anna; Shultz, Allison J; Edwards, Scott V; Robertson, Gregory J; Friesen, Vicki L

2017-04-01

Investigating the extent (or the existence) of local adaptation is crucial to understanding how populations adapt. When experiments or fitness measurements are difficult or impossible to perform in natural populations, genomic techniques allow us to investigate local adaptation through the comparison of allele frequencies and outlier loci along environmental clines. The thick-billed murre ( Uria lomvia ) is a highly philopatric colonial arctic seabird that occupies a significant environmental gradient, shows marked phenotypic differences among colonies, and has large effective population sizes. To test whether thick-billed murres from five colonies along the eastern Canadian Arctic coast show genomic signatures of local adaptation to their breeding grounds, we analyzed geographic variation in genome-wide markers mapped to a newly assembled thick-billed murre reference genome. We used outlier analyses to detect loci putatively under selection, and clustering analyses to investigate patterns of differentiation based on 2220 genomewide single nucleotide polymorphisms (SNPs) and 137 outlier SNPs. We found no evidence of population structure among colonies using all loci but found population structure based on outliers only, where birds from the two northernmost colonies (Minarets and Prince Leopold) grouped with birds from the southernmost colony (Gannet), and birds from Coats and Akpatok were distinct from all other colonies. Although results from our analyses did not support local adaptation along the latitudinal cline of breeding colonies, outlier loci grouped birds from different colonies according to their non-breeding distributions, suggesting that outliers may be informative about adaptation and/or demographic connectivity associated with their migration patterns or nonbreeding grounds.

Flying into Inquiry

ERIC Educational Resources Information Center

Trautmann, Nancy; Fee, Jennifer; Kahler, Phil

2012-01-01

What bird species live in your area? Which migrate and which stay year-round? How do bird populations change over time? Citizen science provides the essential tools to address these questions and more. With ever-growing databases such as Project FeederWatch and eBird, students can connect with people around the world as they make observations,…

Migration ecology and stopover population size of Red Knots Calidris canutus rufa at Mingan Archipelago after exiting the breeding grounds

USGS Publications Warehouse

Lyons, James E.; Baker, Allan J.; González, Patricia M.; Aubry, Yves; Buidin, Christophe; Rochepault, Yann

2018-01-01

Populations of migratory birds present unique conservation challenges given the often vast distances separating critical resources throughout the annual cycle. Migration areas close to the breeding grounds represent a link between two key stages of the annual cycle, and understanding migration ecology as birds exit the breeding grounds may be particularly informative for successful conservation. We studied migration phenology and stopover ecology of an endangered subspecies of the Red Knot Calidris canutus rufa at a migration area relatively close to its breeding range. Using mark-recapture/resight data and a Jolly-Seber model for open populations, we described the arrival and departure schedules, stopover duration, and passage population size at the Mingan Archipelago, Quebec, Canada. Red Knots arrived at the study area in two distinct waves of birds separated by approximately 22 days. Nearly 30% of the passage population arrived in the first wave of arrivals during 15–18 July, and approximately 22% arrived in a second wave during 8–11 August. The sex-ratio in the stopover population at the time of the first wave was slightly skewed toward females, whereas the second wave was heavily skewed toward males. Because males remain on the breeding grounds to care for young, this may reflect successfulbreeding in the year of our study. The estimated stopover duration (population mean) was 11 days (95% credible interval: 10.3–11.7 days), but stopover persistence was variable throughout the season. We estimated a passage population size of 9,450 birds (8,355–10,710), a minimum estimate for reasons related to the duration of our sampling. Mingan Archipelago is thus an important migration area for this endangered subspecies and could be a priority in conservation planning. Our results also emphasize the advantages of mark-recapture/resight approaches for estimating migration phenology and stopover persistence.

Bird flight characteristics near wind turbines in Minnesota

USGS Publications Warehouse

Osborn, R.G.; Dieter, C.D.; Higgins, K.F.; Usgaard, R.E.

1998-01-01

During 1994-1995, we saw 70 species of birds on the Buffalo Ridge Wind Resource Area. In both years bird abundance peaked in spring. Red-winged blackbirds (Agelaius phoeniceus), mallards (Anas platyrhynchos), common grackles (Quiscalus quiscula), and barn swallows (Hirundo rustica) were the species most commonly seen. Most birds (82-84%) flew above or below the height range of wind turbine blades (22-55 m). The Buffalo Ridge Wind Resource Area poses little threat to resident or migrating birds at its current operating level.

Geographical and temporal flexibility in the response to crosswinds by migrating raptors.

PubMed

Klaassen, Raymond H G; Hake, Mikael; Strandberg, Roine; Alerstam, Thomas

2011-05-07

Wind and ocean currents may potentially have important effects on travelling animals, as an animal which does not respond to lateral flow will be drifted from its intended direction of movement. By analysing daily movements of migrating ospreys Pandion haliaetus and marsh harriers Circus aeruginosus, as recorded by satellite telemetry, in relation to global wind data, we showed that these raptors allow on average 47 per cent drift. Furthermore, our analyses revealed significant geographical and temporal variation in the response to crosswinds. During some parts of the migration, the birds drifted and in other parts they compensated or even overcompensated. In some regions, the response of marsh harriers depended on the wind direction. They drifted when the wind came from one side and (over)compensated when the wind came from the opposite side, and this flexible response was different in different geographical regions. These results suggest that migrating raptors modulate their response to crosswinds at different places and times during their travels and show that individual birds use a much more varied repertoire of behavioural responses to wind than hitherto assumed. Our results may also explain why contrasting and variable results have been obtained in previous studies of the effect of wind on bird migration.

Geographical and temporal flexibility in the response to crosswinds by migrating raptors

PubMed Central

Klaassen, Raymond H. G.; Hake, Mikael; Strandberg, Roine; Alerstam, Thomas

2011-01-01

Wind and ocean currents may potentially have important effects on travelling animals, as an animal which does not respond to lateral flow will be drifted from its intended direction of movement. By analysing daily movements of migrating ospreys Pandion haliaetus and marsh harriers Circus aeruginosus, as recorded by satellite telemetry, in relation to global wind data, we showed that these raptors allow on average 47 per cent drift. Furthermore, our analyses revealed significant geographical and temporal variation in the response to crosswinds. During some parts of the migration, the birds drifted and in other parts they compensated or even overcompensated. In some regions, the response of marsh harriers depended on the wind direction. They drifted when the wind came from one side and (over)compensated when the wind came from the opposite side, and this flexible response was different in different geographical regions. These results suggest that migrating raptors modulate their response to crosswinds at different places and times during their travels and show that individual birds use a much more varied repertoire of behavioural responses to wind than hitherto assumed. Our results may also explain why contrasting and variable results have been obtained in previous studies of the effect of wind on bird migration. PMID:20980299

One year of migration data for a western yellow-billed cuckoo

USGS Publications Warehouse

Sechrist, Juddson D.; Paxton, Eben H.; Ahlers, Darrell D.; Doster, Robert H.; Ryan, Vicky M.

2012-01-01

In 2009, we studied the migration of the Western Yellow-billed Cuckoo by capturing 13 breeding birds on the middle Rio Grande, New Mexico, and attaching a 1.5-g Mk 14-S British Antarctic Survey geolocator to each bird. In 2010, we recaptured one of the cuckoos, enabling us to download its geolocation data. The cuckoo had flown approximately 9500 km during its southward migration, traveling through Central America to winter in portions of Bolivia, Brazil, Paraguay, and Argentina. The spring migration route differed somewhat from the fall route, with the cuckoo bypassing Central America to migrate through the Caribbean. Additionally, it moved between New Mexico and Mexico at the end of summer in 2009 and again in 2010 before being recaptured at its breeding site. Our results, albeit from one individual, hint at a dynamic migration strategy and have broad implications for the ecology and conservation of the Western Yellow-billed Cuckoo, a species of conservation concern.

eBird—Using citizen-science data to help solve real-world conservation challenges (Invited)

NASA Astrophysics Data System (ADS)

Sullivan, B. L.; Iliff, M. J.; Wood, C. L.; Fink, D.; Kelling, S.

2010-12-01

eBird (www.ebird.org) is an Internet-based citizen-science project that collects bird observations worldwide. eBird is foremost a tool for birders, providing users with a resource for bird information and a way to keep track of their personal bird lists, thus establishing a model for sustained participation and new project growth. Importantly, eBird data are shared with scientists and conservationists working to save birds and their habitats. Here we highlight two different ways these data are used: as a real-time data gathering and visualization tool; and as the primary resource for developing large-scale bird distribution models that explore species-habitat associations and climate change scenarios. eBird provides data across broad temporal and spatial scales, and is a valuable tool for documenting and monitoring bird populations facing a multitude of anthropogenic and environmental impacts. For example, a focused effort to monitor birds on Gulf Coast beaches using eBird is providing essential baseline data and enabling long-term monitoring of bird populations throughout the region. Additionally, new data visualization tools that incorporate data from eBird, NOAA, and Google, are specifically designed to highlight the potential impacts of the Gulf oil spill on bird populations. Through a collaboration of partners in the DataONE network, such as the Oak Ridge National Laboratory, we will use supercomputing time from the National Science Foundation’s TeraGrid to allow Lab scientists to model bird migration phenology at the population level based on eBird data. The process involves combining bird observations with remotely sensed variables such as landcover and greening index to predict bird movements. Preliminary results of these models allow us to animate bird movements across large spatial scales, and to explore how migration timing might be affected under different climate change scenarios.

Half a World Apart? Overlap in Nonbreeding Distributions of Atlantic and Indian Ocean Thin-Billed Prions

PubMed Central

Quillfeldt, Petra; Cherel, Yves; Masello, Juan F.; Delord, Karine; McGill, Rona A. R.; Furness, Robert W.; Moodley, Yoshan; Weimerskirch, Henri

2015-01-01

Distant populations of animals may share their non-breeding grounds or migrate to distinct areas, and this may have important consequences for population differentiation and dynamics. Small burrow-nesting seabirds provide a suitable case study, as they are often restricted to safe breeding sites on islands, resulting in a patchy breeding distribution. For example, Thin-billed prions Pachyptila belcheri have two major breeding colonies more than 8,000 km apart, on the Falkland Islands in the south-western Atlantic and in the Kerguelen Archipelago in the Indian Ocean. We used geolocators and stable isotopes to compare at-sea movements and trophic levels of these two populations during their non-breeding season, and applied ecological niche models to compare environmental conditions in the habitat. Over three winters, birds breeding in the Atlantic showed a high consistency in their migration routes. Most individuals migrated more than 3000 km eastwards, while very few remained over the Patagonian Shelf. In contrast, all Indian Ocean birds migrated westwards, resulting in an overlapping nonbreeding area in the eastern Atlantic sector of the Southern Ocean. Geolocators and isotopic signature of feathers indicated that prions from the Falklands moulted at slightly higher latitudes than those from Kerguelen Islands. All birds fed on low trophic level prey, most probably crustaceans. The phenology differed notably between the two populations. Falkland birds returned to the Patagonian Shelf after 2-3 months, while Kerguelen birds remained in the nonbreeding area for seven months, before returning to nesting grounds highly synchronously and at high speed. Habitat models identified sea surface temperature and chlorophyll a concentration as important environmental parameters. In summary, we show that even though the two very distant populations migrate to roughly the same area to moult, they have distinct wintering strategies: They had significantly different realized niches and timing which may contribute to spatial niche partitioning. PMID:26018194

Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla

PubMed Central

Carvalho-Paulo, Dario; de Morais Magalhães, Nara G.; de Almeida Miranda, Diego; Diniz, Daniel G.; Henrique, Ediely P.; Moraes, Isis A. M.; Pereira, Patrick D. C.; de Melo, Mauro A. D.; de Lima, Camila M.; de Oliveira, Marcus A.; Guerreiro-Diniz, Cristovam; Sherry, David F.; Diniz, Cristovam W. P.

2018-01-01

Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla, that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D) morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy (n = 249 cells) with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period (n = 250 cells). Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes may play different physiological roles during migration. PMID:29354035

Time versus energy minimization migration strategy varies with body size and season in long-distance migratory shorebirds.

PubMed

Zhao, Meijuan; Christie, Maureen; Coleman, Jonathan; Hassell, Chris; Gosbell, Ken; Lisovski, Simeon; Minton, Clive; Klaassen, Marcel

2017-01-01

Migrants have been hypothesised to use different migration strategies between seasons: a time-minimization strategy during their pre-breeding migration towards the breeding grounds and an energy-minimization strategy during their post-breeding migration towards the wintering grounds. Besides season, we propose body size as a key factor in shaping migratory behaviour. Specifically, given that body size is expected to correlate negatively with maximum migration speed and that large birds tend to use more time to complete their annual life-history events (such as moult, breeding and migration), we hypothesise that large-sized species are time stressed all year round. Consequently, large birds are not only likely to adopt a time-minimization strategy during pre-breeding migration, but also during post-breeding migration, to guarantee a timely arrival at both the non-breeding (i.e. wintering) and breeding grounds. We tested this idea using individual tracks across six long-distance migratory shorebird species (family Scolopacidae) along the East Asian-Australasian Flyway varying in size from 50 g to 750 g lean body mass. Migration performance was compared between pre- and post-breeding migration using four quantifiable migratory behaviours that serve to distinguish between a time- and energy-minimization strategy, including migration speed, number of staging sites, total migration distance and step length from one site to the next. During pre- and post-breeding migration, the shorebirds generally covered similar distances, but they tended to migrate faster, used fewer staging sites, and tended to use longer step lengths during pre-breeding migration. These seasonal differences are consistent with the prediction that a time-minimization strategy is used during pre-breeding migration, whereas an energy-minimization strategy is used during post-breeding migration. However, there was also a tendency for the seasonal difference in migration speed to progressively disappear with an increase in body size, supporting our hypothesis that larger species tend to use time-minimization strategies during both pre- and post-breeding migration. Our study highlights that body size plays an important role in shaping migratory behaviour. Larger migratory bird species are potentially time constrained during not only the pre- but also the post-breeding migration. Conservation of their habitats during both seasons may thus be crucial for averting further population declines.

Black brant from Alaska staging and wintering in Japan

USGS Publications Warehouse

Derksen, Dirk V.; Bollinger, K.S.; Ward, David H.; Sedinger, J.S.; Miyabayashi, Y.

1996-01-01

Black brant (Branta bernicla nigricans) nest in colonies in arctic Canada, Alaska, and Russia (Derksen and Ward 1993, Sedinger et al. 1993). Virtually the entire population stages in fall at Izembek Lagoon near the tip of the Alaska Peninsula (Bellrose 1976) before southward migration (Dau 1992) to winter habitats in British Columbia, Washington, Oregon, California, and Baja California (Subcommittee on Black Brant 1992). A small number of black brant winter in Japan, Korea, and China (Owen 1980). In Japan 3,000–5,000 brant of unknown origin stop over in fall, and a declining population (<1,000) of birds winter here, primarily in the northern islands (Brazil 1991, Miyabayashi et al. 1994). Here, we report sightings of brant in Japan that were marked in Alaska and propose a migration route based on historical and recent observations and weather patterns.

Celestial Moderation of Tropical Seabird Behavior

PubMed Central

Pinet, Patrick; Jaeger, Audrey; Cordier, Emmanuel; Potin, Gaël; Le Corre, Matthieu

2011-01-01

Most animals, including birds, have cyclic life histories and numerous studies generally conducted on captive animals have shown that photoperiod is the main factor influencing this periodicity. Moon cycles can also affect periodic behavior of birds. Few studies have investigated the influence of these environmental cues in natural settings, and particularly in tropical areas where the change in photoperiod is slight and some bird species keep cyclic behaviors. Using miniaturized light sensors, we simultaneously investigated under natural conditions the influence of photoperiod and moon phases on the migration dates and at-sea activity of a tropical seabird species, the Barau's petrel, throughout its annual cycle. Firstly, we found that birds consistently started their pre- and post-breeding migrations at precise dates corresponding in both cases to a day-duration of 12.5 hours, suggesting a strong influence of the photoperiod in the regulation of migration behavior. We also found that mean population arrival dates to the colony changed from year to year and they were influenced by moon phases. Returns at their colonies occurred around the last full moon of the austral winter, suggesting that moon cycle is used by birds to synchronize their arrival. Secondly, variations of day-time activity were sinusoidal and correlated to seasonal changes of daylength. We thus hypothesize that the photoperiod could directly affect the behavior of the birds at sea. Night-time at-sea activity exhibited a clear cycle of 29.2 days, suggesting that nocturnal foraging was highly regulated by moon phase, particularly during the non-breeding season. To our knowledge, this is the first study to document a mixed regulation of the behavior of a wild bird by photoperiod and moon phases throughout its annual cycle. PMID:22110711

Celestial moderation of tropical seabird behavior.

PubMed

Pinet, Patrick; Jaeger, Audrey; Cordier, Emmanuel; Potin, Gaël; Le Corre, Matthieu

2011-01-01

Most animals, including birds, have cyclic life histories and numerous studies generally conducted on captive animals have shown that photoperiod is the main factor influencing this periodicity. Moon cycles can also affect periodic behavior of birds. Few studies have investigated the influence of these environmental cues in natural settings, and particularly in tropical areas where the change in photoperiod is slight and some bird species keep cyclic behaviors. Using miniaturized light sensors, we simultaneously investigated under natural conditions the influence of photoperiod and moon phases on the migration dates and at-sea activity of a tropical seabird species, the Barau's petrel, throughout its annual cycle. Firstly, we found that birds consistently started their pre- and post-breeding migrations at precise dates corresponding in both cases to a day-duration of 12.5 hours, suggesting a strong influence of the photoperiod in the regulation of migration behavior. We also found that mean population arrival dates to the colony changed from year to year and they were influenced by moon phases. Returns at their colonies occurred around the last full moon of the austral winter, suggesting that moon cycle is used by birds to synchronize their arrival. Secondly, variations of day-time activity were sinusoidal and correlated to seasonal changes of daylength. We thus hypothesize that the photoperiod could directly affect the behavior of the birds at sea. Night-time at-sea activity exhibited a clear cycle of 29.2 days, suggesting that nocturnal foraging was highly regulated by moon phase, particularly during the non-breeding season. To our knowledge, this is the first study to document a mixed regulation of the behavior of a wild bird by photoperiod and moon phases throughout its annual cycle.

Flight directions of passerine migrants in daylight and darkness: A radar and direct visual study

NASA Technical Reports Server (NTRS)

Gauthreaux, S. A., Jr.

1972-01-01

The application of radar and visual techniques to determine the migratory habits of passerine birds during daylight and darkness is discussed. The effects of wind on the direction of migration are examined. Scatter diagrams of daytime and nocturnal migration track directions correlated with wind direction are presented. It is concluded that migratory birds will fly at altitudes where wind direction and migratory direction are nearly the same. The effects of cloud cover and solar obscuration are considered negligible.

An evaluation of regression methods to estimate nutritional condition of canvasbacks and other water birds

USGS Publications Warehouse

Sparling, D.W.; Barzen, J.A.; Lovvorn, J.R.; Serie, J.R.

1992-01-01

Regression equations that use mensural data to estimate body condition have been developed for several water birds. These equations often have been based on data that represent different sexes, age classes, or seasons, without being adequately tested for intergroup differences. We used proximate carcass analysis of 538 adult and juvenile canvasbacks (Aythya valisineria ) collected during fall migration, winter, and spring migrations in 1975-76 and 1982-85 to test regression methods for estimating body condition.

Colonization and Containment of Hyalomma Marginatum Rufipes for Studies on the Transmission of Crimean-Congo Hemorrhagic Fever

DTIC Science & Technology

1987-07-31

tick-borne Crimean-Congo hemorrhagic fever in Asia, Europe and Africa. J. Med. Entomol. 15: 307-417. Hoogstraal, H., M. N. Kaiser, M. A. Taylor, S. Gaber ...N. Kaiser, M. A. Taylor, E. Guindy, and S. Gaber . 1963. Tick (Ixodoidea) on birds migrating from Europe and Asia to Africa, 1959-1961. IBID. Pegram...Hoogstraal, H Traylor, M.A., Gaber , S., Malakatis, G., Guindy, E. & Relmy, 1. 1964 ricks (Ixodidae) on migrating birds in Eg ypt, Spring and Fall

Crossing the ultimate ecological barrier: Evidence for an 11,000-km-long non-stop flight from Alaska to New Zealand and Eastern Australia by Bar-tailed Godwits

USGS Publications Warehouse

Gill, Robert E.; Piersma, Theunis; Hufford, Gary; Servranckx, R.; Riegen, Adrian C.

2005-01-01

Populations of the Bar-tailed Godwit (Limosa lapponica; Scolopacidae) embark on some of the longest migrations known among birds. The baueri race breeds in westernAlaska and spends the nonbreeding season a hemisphere away inNew Zealand and eastern Australia; the menzbieri race breeds in Siberia and migrates to western and northern Australia. Although the Siberian birds are known to follow the coast of Asia during both migrations, the southern pathway followed by the Alaskabreeders has remained unknown. Two questions have particularecological importance: (1) do Alaska godwits migrate directly across the Pacific, a distance of 11 000 km? and (2) are they capable of doing this in a single flight without stopping to rest or refuel? We explored six lines of evidence to answer these questions. The distribution of resightings of marked birds of the baueri and menzbieri races was significantly different between northward and southward flights with virtually no marked baueri resighted along the Asian mainland during southward migration. The timing of southward migration of the two races further indicates the absence of a coastal Asia route by baueri with peak passage of godwits in general occurring there a month prior to the departure of most birds from Alaska. The use of a direct route across the Pacific is also supported by significantly more records of godwits reported from within a direct migration corridor than elsewhere in Oceania, and during the September to November period than at other times of the year. The annual but rare occurrence of Hudsonian Godwits (L. haemastica) in New Zealand and the absence of their records along the Asian mainland also support a direct flight and are best explained by Hudsonian Godwits accompanying Bar-tailed Godwits from known communal staging areas in Alaska. Flight simulation models, extreme fat loads, and the apparent evolution of a wind-selected migration from Alaska further support a direct, nonstop flight.

Thinking like a duck: fall lake use and movement patterns of juvenile ring-necked ducks before migration.

PubMed

Roy, Charlotte L; Fieberg, John; Scharenbroich, Christopher; Herwig, Christine M

2014-01-01

The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall.

Multi-species patterns of avian cholera mortality in Nebraska's rainwater basin

USGS Publications Warehouse

Blanchong, Julie A.; Samuel, M.D.; Mack, G.

2006-01-01

Nebraska's Rainwater Basin (RWB) is a key spring migration area for millions of waterfowl and other avian species. Avian cholera has been endemic in the RWB since the 1970s and in some years tens of thousands of waterfowl have died from the disease. We evaluated patterns of avian cholera mortality in waterfowl species using the RWB during the last quarter of the 20th century. Mortality patterns changed between the years before (1976 - 1988) and coincident with (1989 - 1999) the dramatic increases in lesser snow goose abundance and mortality. Lesser snow geese (Chen caerulescens caerulescens) have commonly been associated with mortality events in the RWB and are known to carry virulent strains of Pasteurella multocida, the agent causing avian cholera. Lesser snow geese appeared to be the species most affected by avian cholera during 1989 - 1999; however, mortality in several other waterfowl species was positively correlated with lesser snow goose mortality. Coincident with increased lesser snow goose mortality, spring avian cholera outbreaks were detected earlier and ended earlier compared to 1976 - 1988. Dense concentrations of lesser snow geese may facilitate intraspecific disease transmission through bird-to-bird contact and wetland contamination. Rates of interspecific avian cholera transmission within the waterfowl community, however, are difficult to determine.

Lapland longspur mortality at an oil well drilling rig site, Laramie County, Wyoming

USGS Publications Warehouse

Ramirez, Pedro; Dickerson, Kimberly K.; Lindstrom, Jim; Meteyer, Carol U.; Darrah, Scott

2015-01-01

Two hundred fifty-one Lapland longspur (Calcarius lapponicus) carcasses were recovered around an oil well drilling rig in Laramie County, Wyoming, USA, on December 13–14, 2010, apparent victims of a winter storm and “light entrapment” from the lights on the drilling rig during foggy conditions. We found Lapland longspur carcasses distributed around the drilling rig from 33 m to 171 m. Investigators did not find evidence of bird carcasses on the drilling rig deck or equipment immediately adjacent to the drilling rig. We ruled out chemical toxins and disease as a cause of mortality. Weather conditions, the circular depositional pattern of carcasses around the drilling rig, and bird necropsy results led investigators to conclude that the Lapland longspur mortality was the result of the migrating birds entering the area illuminated by the drilling rig lights in freezing fog and the birds repeatedly circling the drilling rig until they fell to the ground in exhaustion and dying from subsequent trauma. Further research is needed to understand how to most effectively adjust lighting of onshore drilling rigs to reduce the potential for avian light entrapment. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Influence of body condition on influenza A virus infection in mallard ducks: Experimental infection data

USGS Publications Warehouse

Arsnoe, Dustin M.; Ip, Hon S.; Owen, Jennifer C.

2011-01-01

Migrating waterfowl are implicated in the global spread of influenza A viruses (IAVs), and mallards (Anas platyrhynchos) are considered a particularly important IAV reservoir. Prevalence of IAV infection in waterfowl peaks during autumn pre-migration staging and then declines as birds reach wintering areas. Migration is energetically costly and birds often experience declines in body condition that may suppress immune function. We assessed how body condition affects susceptibility to infection, viral shedding and antibody production in wild-caught and captive-bred juvenile mallards challenged with low pathogenic avian influenza virus (LPAIV) H5N9. Wild mallards (n = 30) were separated into three experimental groups; each manipulated through food availability to a different condition level (-20%, -10%, and normal ±5% original body condition), and captive-bred mallards (n = 10) were maintained at normal condition. We found that wild mallards in normal condition were more susceptible to LPAIV infection, shed higher peak viral loads and shed viral RNA more frequently compared to birds in poor condition. Antibody production did not differ according to condition. We found that wild mallards did not differ from captive-bred mallards in viral intensity and duration of infection, but they did exhibit lower antibody titers and greater variation in viral load. Our findings suggest that reduced body condition negatively influences waterfowl host competence to LPAIV infection. This observation is contradictory to the recently proposed condition-dependent hypothesis, according to which birds in reduced condition would be more susceptible to IAV infection. The mechanisms responsible for reducing host competency among birds in poor condition remain unknown. Our research indicates body condition may influence the maintenance and spread of LPAIV by migrating waterfowl.

Influence of body condition on influenza a virus infection in mallard ducks: Experimental infection data

USGS Publications Warehouse

Arsnoe, D.M.; Ip, Hon S.; Owen, J.C.

2011-01-01

Migrating waterfowl are implicated in the global spread of influenza A viruses (IAVs), and mallards (Anas platyrhynchos) are considered a particularly important IAV reservoir. Prevalence of IAV infection in waterfowl peaks during autumn pre-migration staging and then declines as birds reach wintering areas. Migration is energetically costly and birds often experience declines in body condition that may suppress immune function. We assessed how body condition affects susceptibility to infection, viral shedding and antibody production in wild-caught and captive-bred juvenile mallards challenged with low pathogenic avian influenza virus (LPAIV) H5N9. Wild mallards (n = 30) were separated into three experimental groups; each manipulated through food availability to a different condition level (-20%, -10%, and normal ??5% original body condition), and captive-bred mallards (n = 10) were maintained at normal condition. We found that wild mallards in normal condition were more susceptible to LPAIV infection, shed higher peak viral loads and shed viral RNA more frequently compared to birds in poor condition. Antibody production did not differ according to condition. We found that wild mallards did not differ from captive-bred mallards in viral intensity and duration of infection, but they did exhibit lower antibody titers and greater variation in viral load. Our findings suggest that reduced body condition negatively influences waterfowl host competence to LPAIV infection. This observation is contradictory to the recently proposed condition-dependent hypothesis, according to which birds in reduced condition would be more susceptible to IAV infection. The mechanisms responsible for reducing host competency among birds in poor condition remain unknown. Our research indicates body condition may influence the maintenance and spread of LPAIV by migrating waterfowl. ?? 2011 Arsnoe et al.

The impacts of climate change on the annual cycles of birds

PubMed Central

Carey, Cynthia

2009-01-01

Organisms living today are descended from ancestors that experienced considerable climate change in the past. However, they are currently presented with many new, man-made challenges, including rapid climate change. Migration and reproduction of many avian species are controlled by endogenous mechanisms that have been under intense selection over time to ensure that arrival to and departure from breeding grounds is synchronized with moderate temperatures, peak food availability and availability of nesting sites. The timing of egg laying is determined, usually by both endogenous clocks and local factors, so that food availability is near optimal for raising young. Climate change is causing mismatches in food supplies, snow cover and other factors that could severely impact successful migration and reproduction of avian populations unless they are able to adjust to new conditions. Resident (non-migratory) birds also face challenges if precipitation and/or temperature patterns vary in ways that result in mismatches of food and breeding. Predictions that many existing climates will disappear and novel climates will appear in the future suggest that communities will be dramatically restructured by extinctions and changes in range distributions. Species that persist into future climates may be able to do so in part owing to the genetic heritage passed down from ancestors who survived climate changes in the past. PMID:19833644

Connectivity between migrating and landlocked populations of a diadromous fish species investigated using otolith microchemistry.

PubMed

Tulp, Ingrid; Keller, Marieke; Navez, Jacques; Winter, Hendrik V; de Graaf, Martin; Baeyens, Willy

2013-01-01

Smelt Osmerus eperlanus has two different life history strategies in The Netherlands. The migrating population inhabits the Wadden Sea and spawns in freshwater areas. After the closure of the Afsluitdijk in 1932, part of the smelt population became landlocked. The fresh water smelt population has been in severe decline since 1990, and has strongly negatively impacted the numbers of piscivorous water birds relying on smelt as their main prey. The lakes that were formed after the dike closure, IJsselmeer and Markermeer have been assigned as Natura 2000 sites, based on their importance for (among others) piscivorous water birds. Because of the declining fresh water smelt population, the question arose whether this population is still supported by the diadromous population. Opportunities for exchange between fresh water and the sea are however limited to discharge sluices. The relationship between the diadromous and landlocked smelt population was analysed by means of otolith microchemistry. Our interpretation of otolith strontium ((88)Sr) patterns from smelt specimens collected in the fresh water area of Lake IJsselmeer and Markermeer, compared to those collected in the nearby marine environment, is that there is currently no evidence for a substantial contribution from the diadromous population to the spawning stock of the landlocked population.

Flying with the wind: Scale dependency of speed and direction measurements in modelling wind support in avian flight

USGS Publications Warehouse

Safi, Kamran; Kranstauber, Bart; Weinzierl, Rolf P.; Griffin, Larry; Reese, Eileen C.; Cabot, David; Cruz, Sebastian; Proaño, Carolina; Takekawa, John Y.; Newman, Scott H.; Waldenström, Jonas; Bengtsson, Daniel; Kays, Roland; Wikelski, Martin; Bohrer, Gil

2013-01-01

Background: Understanding how environmental conditions, especially wind, influence birds' flight speeds is a prerequisite for understanding many important aspects of bird flight, including optimal migration strategies, navigation, and compensation for wind drift. Recent developments in tracking technology and the increased availability of data on large-scale weather patterns have made it possible to use path annotation to link the location of animals to environmental conditions such as wind speed and direction. However, there are various measures available for describing not only wind conditions but also the bird's flight direction and ground speed, and it is unclear which is best for determining the amount of wind support (the length of the wind vector in a bird’s flight direction) and the influence of cross-winds (the length of the wind vector perpendicular to a bird’s direction) throughout a bird's journey.Results: We compared relationships between cross-wind, wind support and bird movements, using path annotation derived from two different global weather reanalysis datasets and three different measures of direction and speed calculation for 288 individuals of nine bird species. Wind was a strong predictor of bird ground speed, explaining 10-66% of the variance, depending on species. Models using data from different weather sources gave qualitatively similar results; however, determining flight direction and speed from successive locations, even at short (15 min intervals), was inferior to using instantaneous GPS-based measures of speed and direction. Use of successive location data significantly underestimated the birds' ground and airspeed, and also resulted in mistaken associations between cross-winds, wind support, and their interactive effects, in relation to the birds' onward flight.Conclusions: Wind has strong effects on bird flight, and combining GPS technology with path annotation of weather variables allows us to quantify these effects for understanding flight behaviour. The potentially strong influence of scaling effects must be considered and implemented in developing sampling regimes and data analysis.

Bird interactions with offshore oil and gas platforms: review of impacts and monitoring techniques.

PubMed

Ronconi, Robert A; Allard, Karel A; Taylor, Philip D

2015-01-01

Thousands of oil and gas platforms are currently operating in offshore waters globally, and this industry is expected to expand in coming decades. Although the potential environmental impacts of offshore oil and gas activities are widely recognized, there is limited understanding of their impacts on migratory and resident birds. A literature review identified 24 studies and reports of bird-platform interactions, most being qualitative and half having been peer-reviewed. The most frequently observed effect, for seabirds and landbirds, is attraction and sometimes collisions associated with lights and flares; episodic events have caused the deaths of hundreds or even thousands of birds. Though typically unpredictable, anecdotally, it is known that poor weather, such as fog, precipitation and low cloud cover, can exacerbate the effect of nocturnal attraction to lights, especially when coincidental with bird migrations. Other effects include provision of foraging and roosting opportunities, increased exposure to oil and hazardous environments, increased exposure to predators, or repulsion from feeding sites. Current approaches to monitoring birds at offshore platforms have focused on observer-based methods which can offer species-level bird identification, quantify seasonal patterns of relative abundance and distribution, and document avian mortality events and underlying factors. Observer-based monitoring is time-intensive, limited in spatial and temporal coverage, and suffers without clear protocols and when not conducted by trained, independent observers. These difficulties are exacerbated because deleterious bird-platform interaction is episodic and likely requires the coincidence of multiple factors (e.g., darkness, cloud, fog, rain conditions, occurrence of birds in vicinity). Collectively, these considerations suggest a need to implement supplemental systems for monitoring bird activities around offshore platforms. Instrument-based approaches, such as radar, cameras, acoustic recordings, and telemetry, hold promise for continuous monitoring. Recommendations are provided for a rigorous and comprehensive monitoring approach within an adaptive management framework. Copyright © 2014 Elsevier Ltd. All rights reserved.

Post-breeding migration and connectivity of red knots in the Western Atlantic

USGS Publications Warehouse

Lyons, James E.; Winn, Bradford; Keyes, Timothy; Kalasz, Kevin S.

2018-01-01

Red knots (Calidris canutus rufa) have 3 distinct nonbreeding regions: 1 in the southeastern United States and Caribbean, another on the northeast coast of Brazil in the Maranhão region, and a third along the Patagonian coasts of Chile and Argentina. Effective conservation and recovery of this threatened long-distance migrant will require knowledge of population structure, migration ecology, and abundance and distribution throughout the annual cycle. We conducted a stopover population and biogeographic assessment of knots at the Altamaha River Delta, Georgia, an important stopover area in the southeastern United States. We estimated stopover population size and stopover duration during post-breeding migration in 2011 at the Altamaha study area using mark-resight data, and we inferred nonbreeding regions for this stopover population using stable isotope ratios of carbon and nitrogen in feathers, and observations (sightings and captures) during boreal winter from across the hemisphere. With an integrated Bayesian analysis of all these data, we also estimated the number of birds in the southeastern United States and northern Brazil during boreal winter. For mark-resight analyses in Georgia, we made observations of marked individuals during 14 weeks from early August to early November 2011 and detected 814 individually marked birds. We used the Jolly-Seber mark-recapture model and estimated the southbound passage population at approximately 23,400 red knots. In ongoing studies elsewhere, isotope samples were collected from 175 (21%) of the 814 birds detected in our study, and ≥1 sighting or capture record during boreal winter was located in data repositories for 659 birds (81%). Isotopic signatures and boreal winter records indicate that the majority (82–96%) of the birds that stopped at the Altamaha Delta spend the boreal winter in the northern part of the nonbreeding range (southeast USA, Caribbean, and northern Brazil). Knots migrating to the southeastern United States, Caribbean, or Brazil remained on the Altamaha Delta for 42 days, whereas birds migrating to Tierra del Fuego remained only 21 days. Combining our estimate of the Altamaha stopover population size (23,400 birds) and the estimated proportion in the northern nonbreeding region (82–96%), we derived a minimum estimate of the number of knots in the southeastern United States, Caribbean, and northern South America during the boreal winter: approximately 20,800 knots, of which approximately 10,400 knots occupy the southeastern United States and 5,400 occupy Brazil. Our results provide additional evidence that coastal Georgia is an important migration area for red knots, and provide information about population structure and migratory connectivity that will be valuable for conservation planning. 

Why fly the extra mile? Using stress biomarkers to assess wintering habitat quality in migratory shorebirds.

PubMed

Aharon-Rotman, Yaara; Buchanan, Katherine L; Clark, Nicholas J; Klaassen, Marcel; Buttemer, William A

2016-10-01

Migratory birds make decisions about how far to travel based on cost-benefit trade-offs. However, in many cases the net effect of these trade-offs is unclear. We sought to address this question by measuring feather corticosterone (CORTf), leucocyte profile, avian malaria parasite prevalence and estimating fueling rates in three spatially segregated wintering populations of the migratory shorebird ruddy turnstone Arenaria interpres during their stay in the winter habitat. These birds fly from the high-Arctic breeding ground to Australia, but differ in that some decide to end their migration early (Broome, Western Australia), whereas others travel further to either South Australia or Tasmania. We hypothesized that the extra costs in birds migrating greater distances and overwintering in colder climates would be offset by benefits when reaching their destination. This would be evidenced by lower stress biomarkers in populations that travel further, owing to the expected benefits of greater resources and improved vitality. We show that avian malaria prevalence and physiological stress levels were lower in birds flying to South Australia and Tasmania than those overwintering in Broome. Furthermore, our modeling predicts that birds in the southernmost locations enjoy higher fueling rates. Our data are consistent with the interpretation that birds occupying more costly wintering locations in terms of higher migratory flight and thermoregulatory costs are compensated by better feeding conditions and lower blood parasite infections, which facilitates timely and speedy migration back to the breeding ground. These data contribute to our understanding of cost-benefit trade-offs in the decision making underlying migratory behaviour.

Cryptochrome expression in the eye of migratory birds depends on their migratory status.

PubMed

Fusani, Leonida; Bertolucci, Cristiano; Frigato, Elena; Foà, Augusto

2014-03-15

Most passerine birds are nocturnal migrants. When kept in captivity during the migratory periods, these species show a migratory restlessness, or Zugunruhe. Recent studies on Sylvia warblers have shown that Zugunruhe is an excellent proxy of migratory disposition. Passerine birds can use the Earth's geomagnetic field as a compass to keep their course during their migratory flight. Among the candidate magnetoreceptive mechanisms are the cryptochromes, flavoproteins located in the retina that are supposed to perceive the magnetic field through a light-mediated process. Previous work has suggested that expression of Cryptochrome 1 (Cry1) is increased in migratory birds compared with non-migratory species. Here we tested the hypothesis that Cry1 expression depends on migratory status. Blackcaps Sylvia atricapilla were caught before fall migration and held in registration cages. When the birds were showing robust Zugunruhe, we applied a food deprivation protocol that simulates a long migratory flight. When the birds were refed after 2 days, their Zugunruhe decreased substantially, as is expected from birds that would interrupt migration for a refuelling stopover. We found that Cry1 expression was higher at night than during daytime in birds showing Zugunruhe, whereas in birds that underwent the fasting-and-refeeding protocol and reduced their levels of Zugunruhe, night Cry1 expression decreased to daytime levels. Our work shows that Cry1 expression is dependent on the presence of Zugunruhe and not on species-specific or seasonal factors, or on the birds being active versus inactive. These results support the hypothesis that cryptochromes underlie magnetoreceptive mechanisms in birds.

Fall migration routes, timing, and wintering sites of North American ospreys as determined by satellite telemetry

USGS Publications Warehouse

Martell, M.S.; Henny, Charles J.; Nye, P.; Solensky, Matthew J.

2001-01-01

Satellite telemetry was used to determine fall migratory movements of Ospreys (Pandion haliaetus) breeding in the United States. Study areas were established along the lower Columbia River between Oregon and Washington; in north-central Minnesota; on Shelter Island, New York; and in southern New Jersey. Seventy-four adults (25 males, 49 females) were tracked from 1995 through 1999. Migration routes differed among populations but not by sex. Western Ospreys migrated through California and to a lesser degree other western states and wintered in Mexico (88%), El Salvador (6%), and Honduras (6%) (25.9A?N to 13.0A?N and 108.3A?W to 87.3A?W). Minnesota Ospreys migrated along three routes: (1) through the Central U.S. and then along the east coast of Mexico, (2) along the Mississippi River Valley, then across the Gulf of Mexico, or (3) through the southeastern U.S., then across the Caribbean. East Coast birds migrated along the eastern seaboard of the U.S., through Florida, and across the Caribbean. Midwestern birds wintered from Mexico south to Bolivia (22.35A?N to 13.64A?S, and 91.75A?W to 61.76A?W), while East Coast birds wintered from Florida to as far south as Brazil (27.48A?N to 18.5A?S and 80.4A?W to 57.29A?W). Dates of departure from breeding areas differed significantly between sexes and geographic regions, with females leaving earlier than males. Western birds traveled a shorter distance than either midwestern or eastern Ospreys. Females traveled farther than males from the same population, which resulted in females typically wintering south of males.

Habitat suitability index models: redhead (wintering)

USGS Publications Warehouse

Howard, Rebecca J.; Kantrud, Harold A.

1983-01-01

The redhead is a North American waterfowl species with economic as well as ecological importance. It is highly desired by hunters. Retrieved redhead kill in the United States averaged 143,000 birds during the three waterfowl seasons from 1975 to 1977 (U.S. Department of the Interior 1981a, 1981b). Populations on the principal breeding grounds of the redhead--the prairie and parkland region of south-central Canada and north-central United States--averaged 710,000 birds from 1955 to 1981 (Bellrose 1976; A. Novara, U.S. Fish and Wildlife Service [USFWS], Jamestown, North Dakota; pers. comm.). Redhead numbers began to decline in the 1960's. Killing redheads became illegal from 1960 to 1963, and strict bag limits were imposed after that (Bellrose 1976). A breeding population low of 387,000 birds occurred in 1963, but prairie populations began to recover after that time. Their numbers peaked in 1980 when 1,146,000 birds were recorded (A. Novara, pers. comm.). During the fall, over a third of the total redhead population uses the migration corridor that extends from the prairie breeding area to the Texas gulf coast. Another migration corridor extends from the second most important breeding area--the Great Salt Basin--to the Texas coast (Bellrose 1976). During the fall, over a third of the total redhead population uses the migration corridor that extends from the prairie breeding area to the Texas gulf coast. Another migration corridor extends from the second most important breeding area--the Great Salt Basin--to the Texas coast (Bellrose 1976).

Observations of new bird species for San Salvador Island, the Bahamas

Treesearch

Michael E. Akresh; David I. King

2015-01-01

We present our recent observations and compile other accounts of sightings or captures of 30 additional bird species reported for San Salvador Island, The Bahamas, since Sordahl compiled his checklist in 1996. Most are Nearctic-Neotropical migratory birds that either spend the non-breeding season on the island or stop over during migration. Additionally, based on our...

Partners in Flight: past, present, and future: prospects for neotropical migratory bird conservation in Canada

Treesearch

J. S. Wendt

1993-01-01

The plan for conservation of Neotropical Migratory Birds - Partners in Flight - appeals to many Canadians. The birds themselves are loved for their beauty, their song, their mysterious migration, and their faithful return each spring. They are valued as members of healthy ecosystems, especially when they gorge themselves on caterpillars. Canadians recognize that the...

Cross-hemisphere migration of a 25 g songbird

PubMed Central

Bairlein, Franz; Norris, D. Ryan; Nagel, Rolf; Bulte, Marc; Voigt, Christian C.; Fox, James W.; Hussell, David J. T.; Schmaljohann, Heiko

2012-01-01

The northern wheatear (Oenanthe oenanthe) is a small (approx. 25 g), insectivorous migrant with one of the largest ranges of any songbird in the world, breeding from the eastern Canadian Arctic across Greenland, Eurasia and into Alaska (AK). However, there is no evidence that breeding populations in the New World have established overwintering sites in the Western Hemisphere. Using light-level geolocators, we demonstrate that individuals from these New World regions overwinter in northern sub-Sahara Africa, with Alaskan birds travelling approximately 14 500 km each way and an eastern Canadian Arctic bird crossing a wide stretch of the North Atlantic (approx. 3500 km). These remarkable journeys, particularly for a bird of this size, last between one to three months depending on breeding location and season (autumn/spring) and result in mean overall migration speeds of up to 290 km d−1. Stable-hydrogen isotope analysis of winter-grown feathers sampled from breeding birds generally support the notion that Alaskan birds overwinter primarily in eastern Africa and eastern Canadian Arctic birds overwinter mainly in western Africa. Our results provide the first evidence of a migratory songbird capable of linking African ecosystems of the Old World with Arctic regions of the New World. PMID:22337504

Cross-hemisphere migration of a 25 g songbird.

PubMed

Bairlein, Franz; Norris, D Ryan; Nagel, Rolf; Bulte, Marc; Voigt, Christian C; Fox, James W; Hussell, David J T; Schmaljohann, Heiko

2012-08-23

The northern wheatear (Oenanthe oenanthe) is a small (approx. 25 g), insectivorous migrant with one of the largest ranges of any songbird in the world, breeding from the eastern Canadian Arctic across Greenland, Eurasia and into Alaska (AK). However, there is no evidence that breeding populations in the New World have established overwintering sites in the Western Hemisphere. Using light-level geolocators, we demonstrate that individuals from these New World regions overwinter in northern sub-Sahara Africa, with Alaskan birds travelling approximately 14 500 km each way and an eastern Canadian Arctic bird crossing a wide stretch of the North Atlantic (approx. 3500 km). These remarkable journeys, particularly for a bird of this size, last between one to three months depending on breeding location and season (autumn/spring) and result in mean overall migration speeds of up to 290 km d(-1). Stable-hydrogen isotope analysis of winter-grown feathers sampled from breeding birds generally support the notion that Alaskan birds overwinter primarily in eastern Africa and eastern Canadian Arctic birds overwinter mainly in western Africa. Our results provide the first evidence of a migratory songbird capable of linking African ecosystems of the Old World with Arctic regions of the New World.

Breeding and moulting locations and migration patterns of the Atlantic population of Steller's eiders Polysticta stelleri as determined from satellite telemetry

USGS Publications Warehouse

Petersen, M.R.; Bustnes, J.O.; Systad, G.H.

2006-01-01

This study was designed to determine the spring, summer, autumn, and early winter distribution, migration routes, and timing of migration of the Atlantic population of Steller's eiders Polysticta stelleri. Satellite transmitters were implanted in 20 eiders captured in April 2001 at Vads??, Norway, and their locations were determined from 5 May 2001 to 6 February 2002. Regions where birds concentrated from spring until returning to wintering areas included coastal waters from western Finnmark, Norway, to the eastern Taymyr Peninsula, Russia. Novaya Zemlya, Russia, particularly the Mollera Bay region, was used extensively during spring staging, moult, and autumn staging; regions of the Kola, Kanin, and Gydanskiy peninsulas, Russia, were used extensively during spring and moult migrations. Steller's eiders migrated across the Barents and Kara seas and along the Kara Sea and Kola Peninsula coastal waters to nesting, moulting, and wintering areas. The majority of marked eiders (9 of 15) were flightless in near-shore waters along the west side of Novaya Zemlya. Eiders were also flightless in northern Norway and along the Kanin and at Kola Peninsula coasts. We compare and contrast natural history characteristics of the Atlantic and Pacific populations and discuss evolutionary and ecological factors influencing their distribution. © Journal of Avian Biology.

Premigrational movements and behavior of young mallards and wood ducks in north-central Minnesota

USGS Publications Warehouse

Kirby, R.E.; Cowardin, L.M.; Tester, J.R.

1989-01-01

Movements and behavior of 89 young mallards (Anas platyrhynchos) and 48 young wood ducks (Aix sponsa) were monitored on a 932-km2 study area in north-central Minnesota in late summer and fall, 1972-74, with telemetry, visual observation, and aerial surveys. Initial flights of both species were confined to the natal (brood) marsh; first flights away from the natal marsh occurred in the third week after fledging in both species. First flights of young mallards and wood ducks away from their natal marshes were not significantly different between the sexes (mallard, mean = 4.95 km for females and 5.83 km for males; wood ducks, mean = 2.31 km for females and 2.64 km for males). However, flights away from the brood marshes by wood ducks were significantly shorter than for mallards.As young mallards and wood ducks grew, their daytime use of the natal marshes decreased in an irregular pattern as both species began daily flights between day- and night-use areas. Locally reared mallards made longer daily flights between use areas than did wood ducks, but wood ducks changed use areas with greater frequency before 1 October. Despite often extensive movements, most locally reared mallards and wood ducks remained in the vicinity of their brood marshes throughout fall until migration.Movement of young birds to new habitat was not the result of random searching and thus fortuitous discovery of nearby areas. Instead, birds seemed to learn of new habitat and develop movement patterns by associating with other birds; locally reared young always moved in the company of flocks of conspecifics that included adults and older immatures.Differences in movement patterns between the sexes of young birds and between young and adult birds cause them to be differentially distributed by age and sex on and near the breeding grounds. These differences are ultimately reflected in the distribution of the hunter harvest. We have interpreted generalizations about such phenomena, developed from analysis of continent-wide mallard banding data, using our data obtained from individually marked birds. We document (a) greater distances moved by early than by late-hatched young in the postbreeding period before migration, (b) differential movement of age and sex cohorts that explains greater hunting mortality of young than adults and of females than males near natal marshes, (c) differences in length and timing of postbreeding movements of adult male mallards and the postfledging movements of immature male mallards that help explain the northerly continental recovery distribution of young males, and (d) differential timing and rate of movement by birds through harvest areas (early departure of males and some return of females to natal marshes after the beginning of hunting) that explain differences in the timing of hunting season recoveries. Behavioral differences between the age and sex cohorts in the fall waterfowl population on and near their breeding grounds in north-central Minnesota can explain observed differences in survival and recovery rates of adult and young birds.The behaviors observed suggest to us that restrictive harvest regulations such as small-area closure may have little or no local benefits at the breeding grounds because premigratory assemblages of birds make extensive movements. In particular, protection of postbreeding adult females and locally reared young might only occur by closing large areas or scheduling extreme delays in the season opening, neither of which may be compatible with equitably apportioning waterfowl harvest at higher latitudes. Additional research on the local effects of restrictive regulations, and on age- and sex-specific differences in the timing, rate, and direction of fall movements of postbreeding waterfowl is needed.

Chewing lice from wild birds in northern Greece.

PubMed

Diakou, Anastasia; Pedroso Couto Soares, José Bernardo; Alivizatos, Haralambos; Panagiotopoulou, Maria; Kazantzidis, Savas; Literák, Ivan; Sychra, Oldřich

2017-10-01

Greece represents an important area for wild birds due to its geographical position and habitat diversity. Although the bird species in Greece are well recorded, the information about the chewing lice that infest them is practically non-existent. Thus, the aim of the present study was to record the species of lice infesting wild birds in northern Greece and furthermore, to associate the infestation prevalence with factors such as the age, sex, migration and social behaviour of the host as well as the time of the year. In total 729 birds, (belonging to 9 orders, 32 families and 68 species) were examined in 7 localities of northern Greece, during 9 ringing sessions from June 2013 until October 2015. Eighty (11%) of the birds were found to be infested with lice. In 31 different bird species, 560 specimens of lice, belonging to 33 species were recorded. Mixed infestations were recorded in 11 cases where birds were infested with 2-3 different lice species. Four new host-parasite associations were recorded i.e. Menacanthus curuccae from Acrocephalus melanopogon, Menacanthus agilis from Cettia cetti, Myrsidea sp. from Acrocephalus schoenobaenus, and Philopretus citrinellae from Spinus spinus. Moreover, Menacanthus sinuatus was detected on Poecile lugubris, rendering this report the first record of louse infestation in this bird species. The statistical analysis of the data collected showed no association between parasitological parameters (prevalence, mean and median intensity and mean abundance) in two different periods of the year (breeding vs post-breeding season). However, there was a statistically significant difference in the prevalence of infestation between a) migrating and sedentary passerine birds (7.4% vs 13.2%), b) colonial and territorial birds (54.5% vs 9.6%), and c) female and male birds in breeding period (2.6% vs 15.6%). Copyright © 2017. Published by Elsevier B.V.

Temporal and spatial variation in bird and human use of beaches in southern California

USGS Publications Warehouse

Lafferty, Kevin D.; Rodriguez, Donald A.; Chapman, Angela

2013-01-01

Southern California’s beaches can support a remarkable diversity of birds along the Pacific Flyway. We asked whether seasonal, annual, and spatial factors affect bird richness and abundance on public beaches. To do so, we conducted three years of monthly bird surveys on 12 sandy beaches in Ventura California. Across all surveys, we counted 22 shorebird species, 8 gull species, 24 other water bird species, and 24 landbird species. Sanderling, western gull, Heerman’s gull, willet, marbled godwit, and whimbrel were the most abundant members of the bird community. Beach wrack was uncommon, particularly where beaches were groomed, and did not have a large effect on bird abundance, though it was positively associated with overall bird richness. Beaches near estuaries tended to be wide, and such beaches had a higher richness and abundance of birds. Beaches with shallow slopes tended to have more gulls and shorebirds. People and (illegal) unleashed dogs were common, particularly at beaches fronted by houses. The abundance and richness of shorebirds and the richness of other waterbirds was lower where human activity was high. Bird richness and abundance was strongly affected by season, with the highest density of birds being seen during the fall shorebird migration. Gull abundance peaked earlier (August-September) than shorebird abundance (October through December). A brief pulse of shorebirds also occurred in May due to spring migration. Comparing these data with surveys in the 1990’s found no evidence for a decline in shorebirds over time, though black-bellied plover appear to still be recovering from the strong 1997-1998 ENSO. Opportunities to conserve birds on these beaches are limited, but could include enforcing leash laws and setting up human exclosures near estuary mouths.

Ghrelin affects stopover decisions and food intake in a long-distance migrant

PubMed Central

Lupi, Sara; Kaiya, Hiroyuki; Cardinale, Massimiliano

2017-01-01

Billions of birds migrate long distances to either reach breeding areas or to spend the winter at more benign places. On migration, most passerines frequently stop over to rest and replenish their fuel reserves. To date, we know little regarding how they decide that they are ready to continue their journey. What physiological signals tell a bird’s brain that its fuel reserves are sufficient to resume migration? A network of hormones regulates food intake and body mass in vertebrates, including the recently discovered peptide hormone, ghrelin. Here, we show that ghrelin reflects body condition and influences migratory behavior of wild birds. We measured ghrelin levels of wild garden warblers (Sylvia borin) captured at a stopover site. Further, we manipulated blood concentrations of ghrelin to test its effects on food intake and migratory restlessness. We found that acylated ghrelin concentrations of garden warblers with larger fat scores were higher than those of birds without fat stores. Further, injections of unacylated ghrelin decreased food intake and increased migratory restlessness. These results represent experimental evidence that appetite-regulating hormones control migratory behavior. Our study lays a milestone in migration physiology because it provides the missing link between ecologically dependent factors such as condition and timing of migration. In addition, it offers insights in the regulation of the hormonal system controlling food intake and energy stores in vertebrates, whose disruption causes eating disorders and obesity. PMID:28167792

Movement ecology of migration in turkey vultures

PubMed Central

Mandel, J. T.; Bildstein, K. L.; Bohrer, G.; Winkler, D. W.

2008-01-01

We develop individual-based movement ecology models (MEM) to explore turkey vulture (Cathartes aura) migration decisions at both hourly and daily scales. Vulture movements in 10 migration events were recorded with satellite-reporting GPS sensors, and flight behavior was observed visually, aided by on-the-ground VHF radio-tracking. We used the North American Regional Reanalysis dataset to obtain values for wind speed, turbulent kinetic energy (TKE), and cloud height and used a digital elevation model for a measure of terrain ruggedness. A turkey vulture fitted with a heart-rate logger during 124 h of flight during 38 contiguous days showed only a small increase in mean heart rate as distance traveled per day increased, which suggests that, unlike flapping, soaring flight does not lead to greatly increased metabolic costs. Data from 10 migrations for 724 hourly segments and 152 daily segments showed that vultures depended heavily upon high levels of TKE in the atmospheric boundary layer to increase flight distances and maintain preferred bearings at both hourly and daily scales. We suggest how the MEM can be extended to other spatial and temporal scales of avian migration. Our success in relating model-derived atmospheric variables to migration indicates the potential of using regional reanalysis data, as here, and potentially other regional, higher-resolution, atmospheric models in predicting changing movement patterns of soaring birds under various scenarios of climate and land use change. PMID:19060195

A Systematic Review of the Comparative Epidemiology of Avian and Human Influenza A H5N1 and H7N9 - Lessons and Unanswered Questions.

PubMed

Bui, C; Bethmont, A; Chughtai, A A; Gardner, L; Sarkar, S; Hassan, S; Seale, H; MacIntyre, C R

2016-12-01

The aim of this work was to explore the comparative epidemiology of influenza viruses, H5N1 and H7N9, in both bird and human populations. Specifically, the article examines similarities and differences between the two viruses in their genetic characteristics, distribution patterns in human and bird populations and postulated mechanisms of global spread. In summary, H5N1 is pathogenic in birds, while H7N9 is not. Yet both have caused sporadic human cases, without evidence of sustained, human-to-human spread. The number of H7N9 human cases in the first year following its emergence far exceeded that of H5N1 over the same time frame. Despite the higher incidence of H7N9, the spatial distribution of H5N1 within a comparable time frame is considerably greater than that of H7N9, both within China and globally. The pattern of spread of H5N1 in humans and birds around the world is consistent with spread through wild bird migration and poultry trade activities. In contrast, human cases of H7N9 and isolations of H7N9 in birds and the environment have largely occurred in a number of contiguous provinces in south-eastern China. Although rates of contact with birds appear to be similar in H5N1 and H7N9 cases, there is a predominance of incidental contact reported for H7N9 as opposed to close, high-risk contact for H5N1. Despite the high number of human cases of H7N9 and the assumed transmission being from birds, the corresponding level of H7N9 virus in birds in surveillance studies has been low, particularly in poultry farms. H7N9 viruses are also diversifying at a much greater rate than H5N1 viruses. Analyses of certain H7N9 strains demonstrate similarities with engineered transmissible H5N1 viruses which make it more adaptable to the human respiratory tract. These differences in the human and bird epidemiology of H5N1 and H7N9 raise unanswered questions as to how H7N9 has spread, which should be investigated further. © 2015 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

Stopover decision during migration: physiological conditions predict nocturnal restlessness in wild passerines.

PubMed

Fusani, Leonida; Cardinale, Massimiliano; Carere, Claudio; Goymann, Wolfgang

2009-06-23

During migration, a number of bird species rely on stopover sites for resting and feeding before and after crossing ecological barriers such as deserts or seas. The duration of a stopover depends on the combined effects of environmental factors, endogenous programmes and physiological conditions. Previous studies indicated that lean birds prolong their refuelling stopover compared with fat birds; however, the quantitative relationship between physiological conditions and stopover behaviour has not been studied yet. Here, we tested in a large sample of free-living birds of three European passerines (whinchats, Saxicola rubetra, garden warblers, Sylvia borin and whitethroats, Sylvia communis) whether the amount of migratory restlessness (Zugunruhe) shown at a stopover site depends on physiological conditions. An integrated measure of condition based on body mass, amount of subcutaneous fat and thickness of pectoral muscles strongly predicted the intensity of Zugunruhe shown in recording cages in the night following capture. These results provide novel and robust quantitative evidence in support of the hypothesis that the amount of energy reserves plays a major role in determining the stopover duration in migratory birds.

Stopover decision during migration: physiological conditions predict nocturnal restlessness in wild passerines

PubMed Central

Fusani, Leonida; Cardinale, Massimiliano; Carere, Claudio; Goymann, Wolfgang

2009-01-01

During migration, a number of bird species rely on stopover sites for resting and feeding before and after crossing ecological barriers such as deserts or seas. The duration of a stopover depends on the combined effects of environmental factors, endogenous programmes and physiological conditions. Previous studies indicated that lean birds prolong their refuelling stopover compared with fat birds; however, the quantitative relationship between physiological conditions and stopover behaviour has not been studied yet. Here, we tested in a large sample of free-living birds of three European passerines (whinchats, Saxicola rubetra, garden warblers, Sylvia borin and whitethroats, Sylvia communis) whether the amount of migratory restlessness (Zugunruhe) shown at a stopover site depends on physiological conditions. An integrated measure of condition based on body mass, amount of subcutaneous fat and thickness of pectoral muscles strongly predicted the intensity of Zugunruhe shown in recording cages in the night following capture. These results provide novel and robust quantitative evidence in support of the hypothesis that the amount of energy reserves plays a major role in determining the stopover duration in migratory birds. PMID:19324648

Mercury and cause of death in great white herons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spalding, M.G.; Sundlof, S.F.; Djork, R.D.

1994-10-01

Mercury contamination is suspected to adversely affect wading birds in southern Florida. To determine the magnitude of contamination associated with cause of death we followed 3 adult and 19 juvenile radio-tagged great white herons (Ardea herodias occidentalis), recovered them soon after death, and determined liver mercury content and cause of death. Birds that died from acute causes had less (P < 0.001) mercury in their livers (geometric [bar x] [GM] = 1.77 ppm wet mass [wm], range 0.6-4.0 ppm, n = 9) than did those that died of chronic, often multiple, diseases (GM = 9.76 ppm, range 2.9-59.4 ppm, nmore » = 13). Juvenile herons that migrated to mainland Florida accumulated more (P = 0.009) mercury in their livers than those that did not migrate. Kidney disease and gout were present in birds that died with >25 ppm wm liver mercury. Although detrimental to the health of wading birds, mercury contamination is presumably more detrimental to their reproductive efforts; therefore, an understanding of its ill effects is important in the management of these birds. 29 refs., 1 fig.« less

Final Project Memorandum: Ecological implications of mangrove forest migration in the southeastern U.S.

USGS Publications Warehouse

Osland, Michael J.; Day, Richard H.; Krauss, Ken W.; From, Andrew S.; Larriviere, Jack C.; Hester, Mark W.; Yando, Erik S.; Willis, Jonathan A

2014-01-01

Winter climate change has the potential to have a large impact on coastal wetlands in the southeastern United States. Warmer winter temperatures and reductions in the intensity of freeze events would likely lead to mangrove forest range expansion and salt marsh displacement in parts of the U.S. Gulf of Mexico and Atlantic coast. The objective of this research was to better evaluate the ecological implications of mangrove forest migration and salt marsh displacement. The potential ecological impacts of mangrove migration are diverse ranging from important biotic impacts (e.g., coastal fisheries, land bird migration; colonial-nesting wading birds) to ecosystem stability (e.g., response to sea level rise and drought; habitat loss; coastal protection) to biogeochemical processes (e.g., carbon storage; water quality). This research specifically investigated the impact of mangrove forest migration on coastal wetland soil processes and the consequent implications for coastal wetland responses to sea level rise and carbon storage.

Broad-scale response of landbird migration to the immediate effects of Hurricane Katrina: Chapter 6B in Science and the storms-the USGS response to the hurricanes of 2005

USGS Publications Warehouse

Barrow, Wylie; Buler, J.; Couvillion, Brady R.; Diehl, Robb; Faulkner, Stephen; Moore, F.; Randall, Lori

2007-01-01

It was the midst of songbird migration season when Hurricane Katrina hit the Louisiana coast in 2005. Typically these birds fatten up in Gulf Coast river bottomland forest for the long flight to Central and South America. After Katrina stripped plants of leaves, fruits, and insects in the fertile bottomlands of the Pearl River, weather radar indicated that migrant birds increased their use of adjacent pine woodlands.

Temperature alters the photoperiodically controlled phenologies linked with migration and reproduction in a night-migratory songbird

PubMed Central

Singh, Jyoti; Budki, Puja; Rani, Sangeeta; Kumar, Vinod

2012-01-01

We investigated the effects of temperature on photoperiodic induction of the phenologies linked with migration (body fattening and premigratory night-time restlessness, Zugunruhe) and reproduction (testicular maturation) in the migratory blackheaded bunting. Birds were exposed for four weeks to near-threshold photoperiods required to induce testicular growth (11.5 L:12.5 D and 12 L:12 D) or for 18 weeks to a long photoperiod (13 L:11 D) at 22°C or 27°C (low) and 35°C or 40°C (high) temperatures. A significant body fattening and half-maximal testicular growth occurred in birds under the 12 L, but not under the 11.5 L photoperiod. Further, one of six birds in both temperature groups on 11.5 L, and four and two of six birds, respectively, in low- and high-temperature groups on 12 L showed the Zugunruhe. Buntings on 13 L in both temperature groups showed complete growth-regression cycles in body fattening, Zugunruhe and testis maturation. In birds on 13 L, high temperature attenuated activity levels, delayed onset of Zugunruhe by about 12 days, reduced body fattening and slowed testicular maturation. The effect of temperature seems to be on the rate of photoperiodic induction rather than on the critical day length. It is suggested that a change in temperature could alter the timing of the development of phenologies linked with seasonal migration and reproduction in migratory songbirds. PMID:21715403

Air speeds of migrating birds observed by ornithodolite and compared with predictions from flight theory

PubMed Central

Pennycuick, C. J.; Åkesson, Susanne; Hedenström, Anders

2013-01-01

We measured the air speeds of 31 bird species, for which we had body mass and wing measurements, migrating along the east coast of Sweden in autumn, using a Vectronix Vector 21 ornithodolite and a Gill WindSonic anemometer. We expected each species’ average air speed to exceed its calculated minimum-power speed (Vmp), and to fall below its maximum-range speed (Vmr), but found some exceptions to both limits. To resolve these discrepancies, we first reduced the assumed induced power factor for all species from 1.2 to 0.9, attributing this to splayed and up-turned primary feathers, and then assigned body drag coefficients for different species down to 0.060 for small waders, and up to 0.12 for the mute swan, in the Reynolds number range 25 000–250 000. These results will be used to amend the default values in existing software that estimates fuel consumption in migration, energy heights on arrival and other aspects of flight performance, using classical aeronautical theory. The body drag coefficients are central to range calculations. Although they cannot be measured on dead bird bodies, they could be checked against wind tunnel measurements on living birds, using existing methods. PMID:23804440

The Identification of Military Installations as Important Migratory Bird Stopover Sites and the Development of Bird Migration Forecast Models: A Radar Ornithology Approach

DTIC Science & Technology

2012-08-01

between fat score (Helms and Drury 1960) and the condition index (R2 = 0.56, P < 0.001). A condition index of zero corresponds to zero fat stores or...where bird-wildlife/aircraft collisions threaten lives and cost millions of dollars in damages to aircraft infrastructure every year. By identifying...from bird-aircraft strikes (Dolbeer 2006). In the United States, collisions between aircraft and wildlife cost the aviation industry over $600

The El Niño–Southern Oscillation (ENSO)–pandemic Influenza connection: Coincident or causal?

PubMed Central

Shaman, Jeffrey; Lipsitch, Marc

2013-01-01

We find that the four most recent human influenza pandemics (1918, 1957, 1968, and 2009), all of which were first identified in boreal spring or summer, were preceded by La Niña conditions in the equatorial Pacific. Changes in the phase of the El Niño–Southern Oscillation have been shown to alter the migration, stopover time, fitness, and interspecies mixing of migratory birds, and consequently, likely affect their mixing with domestic animals. We hypothesize that La Niña conditions bring divergent influenza subtypes together in some parts of the world and favor the reassortment of influenza through simultaneous multiple infection of individual hosts and the generation of novel pandemic strains. We propose approaches to test this hypothesis using influenza population genetics, virus prevalence in various host species, and avian migration patterns. PMID:22308322

Post-fledging survival in passerine birds and the value of post-fledging studies to conservation

Treesearch

W. Andrew Cox; Frank R. III Thompson; Allison S. Cox; John Faaborg

2014-01-01

Conservation efforts are most effective when we have complete demographic information for a species of concern. Nevertheless, fundamental gaps in our knowledge of demography still exist for many taxa. For passerine birds, the period of time directly after young birds leave the nest and before they disperse and/or migrate (i.e., the post-fledging period) remains an...

Isolation and genetic characterization of avian influenza viruses isolated from wild birds in the Azov-Black Sea Region of Ukraine (2001–2012)

USDA-ARS?s Scientific Manuscript database

Wild bird surveillance for avian influenza virus (AIV) was conducted from 2001 to 2012 in the Azov - Black Sea region of the Ukraine, considered part of the transcontinental wild bird migration routes from northern Asia and Europe to the Mediterranean, Africa, and southwest Asia. A total of 6281 sam...

A new conservation partnership: conserving the migratory birds of the Americas

Treesearch

Jack C. Capp; David Mehlman

Over five billion birds move each year across the Americas, flying great distances over almost every location and habitat on the continents (Weidensaul 1999). Over 350 of the over 800 bird species in the United States migrate each year to Latin America and the Caribbean (Degraaf and Rappole 1995). Some fly each way over 4000 miles, chasing the seasons across oceans and...

Tracking radar studies of bird migration

NASA Technical Reports Server (NTRS)

Williams, T. C.; Williams, J. M.; Teal, J. M.; Kanwisher, J. W.

1972-01-01

The application of tracking radar for determining the flight paths of migratory birds is discussed. The effects produced by various meteorological parameters are described. Samples of radar scope presentations obtained during tracking studies are presented. The characteristics of the radars and their limitations are examined.

Embolectomy of a Bird's Nest Vena Caval Filter.

PubMed

Chitwood, W R; Chiang, K S; Williams, J M; Zeri, R S; Semer, D A

1994-12-01

In this case report we describe a successful embolectomy of a partially migrated Bird's Nest Caval Filter with attached embolic material. We used transesophageal echocardiography to guide the surgical approach. The patient recovered uneventfully from both the embolectomy and the subsequent pelvic operation.

Convergent evolution in locomotory patterns of flying and swimming animals.

PubMed

Gleiss, Adrian C; Jorgensen, Salvador J; Liebsch, Nikolai; Sala, Juan E; Norman, Brad; Hays, Graeme C; Quintana, Flavio; Grundy, Edward; Campagna, Claudio; Trites, Andrew W; Block, Barbara A; Wilson, Rory P

2011-06-14

Locomotion is one of the major energetic costs faced by animals and various strategies have evolved to reduce its cost. Birds use interspersed periods of flapping and gliding to reduce the mechanical requirements of level flight while undergoing cyclical changes in flight altitude, known as undulating flight. Here we equipped free-ranging marine vertebrates with accelerometers and demonstrate that gait patterns resembling undulating flight occur in four marine vertebrate species comprising sharks and pinnipeds. Both sharks and pinnipeds display intermittent gliding interspersed with powered locomotion. We suggest, that the convergent use of similar gait patterns by distinct groups of animals points to universal physical and physiological principles that operate beyond taxonomic limits and shape common solutions to increase energetic efficiency. Energetically expensive large-scale migrations performed by many vertebrates provide common selection pressure for efficient locomotion, with potential for the convergence of locomotory strategies by a wide variety of species.

Modeling nonbreeding distributions of shorebirds and waterfowl in response to climate change

USGS Publications Warehouse

Reese, Gordon; Skagen, Susan K.

2017-01-01

To identify areas on the landscape that may contribute to a robust network of conservation areas, we modeled the probabilities of occurrence of several en route migratory shorebirds and wintering waterfowl in the southern Great Plains of North America, including responses to changing climate. We predominantly used data from the eBird citizen-science project to model probabilities of occurrence relative to land-use patterns, spatial distribution of wetlands, and climate. We projected models to potential future climate conditions using five representative general circulation models of the Coupled Model Intercomparison Project 5 (CMIP5). We used Random Forests to model probabilities of occurrence and compared the time periods 1981–2010 (hindcast) and 2041–2070 (forecast) in “model space.” Projected changes in shorebird probabilities of occurrence varied with species-specific general distribution pattern, migration distance, and spatial extent. Species using the western and northern portion of the study area exhibited the greatest likelihoods of decline, whereas species with more easterly occurrences, mostly long-distance migrants, had the greatest projected increases in probability of occurrence. At an ecoregional extent, differences in probabilities of shorebird occurrence ranged from −0.015 to 0.045 when averaged across climate models, with the largest increases occurring early in migration. Spatial shifts are predicted for several shorebird species. Probabilities of occurrence of wintering Mallards and Northern Pintail are predicted to increase by 0.046 and 0.061, respectively, with northward shifts projected for both species. When incorporated into partner land management decision tools, results at ecoregional extents can be used to identify wetland complexes with the greatest potential to support birds in the nonbreeding season under a wide range of future climate scenarios.

Passerine migrant stopover duration and spatial behaviour at an urban stopover site

NASA Astrophysics Data System (ADS)

Seewagen, Chad L.; Slayton, Eric J.; Guglielmo, Christopher G.

2010-09-01

Migration routes of many Nearctic-Neotropical landbirds pass through the most urbanized regions of North America. Migrants are known to use urban habitats as stopover sites and often occur in cities at exceptional density; yet knowledge of migrant behaviour and ecology in such places is surprisingly limited. We radio-tracked ovenbirds ( Seiurus aurocapillus) during stopovers in a New York City park to obtain some of the first detailed information on how landbird migrants utilize an urban habitat as a stopover site. We examined fine-scale movement patterns, home range sizes, stopover durations, and how arrival condition affected each of these metrics. During both seasons, most birds moved widely throughout the site upon presumed arrival and then either continued migration that night or settled into a more defined area on subsequent days. Area usage varied markedly among individuals during both seasons, ranging 1-16 ha. Stopover durations averaged 3.0 days (range = 1-10 days) during spring and 2.9 days (range = 1-14 days) during autumn. Spatial behaviours and stopover durations were not influenced by arrival condition during spring, and during autumn only movement rates and displacement distances were significantly (negatively) condition-related. Our findings do not support previous assumptions that urban stopover habitats are only used by migrants briefly in times of urgency when alternatives are unavailable. At least half of the birds we studied stopped over for multiple days during both seasons, and bird movements were indicative of an ability to search for, locate, and occupy suitable micro-sites. Ovenbird behaviour in our study site was similar in many ways to what has been observed in recent telemetry studies of ovenbirds and other passerine migrants at various non-urban stopover sites.

Ecology of playa lakes

USGS Publications Warehouse

Haukos, David A.; Smith, Loren M.

1992-01-01

Between 25,000 and 30,000 playa lakes are in the playa lakes region of the southern high plains (Fig. 1). Most playas are in west Texas (about 20,000), and fewer, in New Mexico, Oklahoma, Kansas, and Colorado. The playa lakes region is one of the most intensively cultivated areas of North America. Dominant crops range from cotton in southern areas to cereal grains in the north. Therefore, most of the native short-grass prairie is gone, replaced by crops and, recently, grasses of the Conservation Reserve Program. Playas are the predominant wetlands and major wildlife habitat of the region.More than 115 bird species, including 20 species of waterfowl, and 10 mammal species have been documented in playas. Waterfowl nest in the area, producing up to 250,000 ducklings in wetter years. Dominant breeding and nesting species are mallards and blue-winged teals. During the very protracted breeding season, birds hatch from April through August. Several million shorebirds and waterfowl migrate through the area each spring and fall. More than 400,000 sandhill cranes migrate through and winter in the region, concentrating primarily on the larger saline lakes in the southern portion of the playa lakes region.The primary importance of the playa lakes region to waterfowl is as a wintering area. Wintering waterfowl populations in the playa lakes region range from 1 to 3 million birds, depending on fall precipitation patterns that determine the number of flooded playas. The most common wintering ducks are mallards, northern pintails, green-winged teals, and American wigeons. About 500,000 Canada geese and 100,000 lesser snow geese winter in the playa lakes region, and numbers of geese have increased annually since the early 1980’s. This chapter describes the physiography and ecology of playa lakes and their attributes that benefit waterfowl.

Tracking of Arctic terns Sterna paradisaea reveals longest animal migration.

PubMed

Egevang, Carsten; Stenhouse, Iain J; Phillips, Richard A; Petersen, Aevar; Fox, James W; Silk, Janet R D

2010-02-02

The study of long-distance migration provides insights into the habits and performance of organisms at the limit of their physical abilities. The Arctic tern Sterna paradisaea is the epitome of such behavior; despite its small size (<125 g), banding recoveries and at-sea surveys suggest that its annual migration from boreal and high Arctic breeding grounds to the Southern Ocean may be the longest seasonal movement of any animal. Our tracking of 11 Arctic terns fitted with miniature (1.4-g) geolocators revealed that these birds do indeed travel huge distances (more than 80,000 km annually for some individuals). As well as confirming the location of the main wintering region, we also identified a previously unknown oceanic stopover area in the North Atlantic used by birds from at least two breeding populations (from Greenland and Iceland). Although birds from the same colony took one of two alternative southbound migration routes following the African or South American coast, all returned on a broadly similar, sigmoidal trajectory, crossing from east to west in the Atlantic in the region of the equatorial Intertropical Convergence Zone. Arctic terns clearly target regions of high marine productivity both as stopover and wintering areas, and exploit prevailing global wind systems to reduce flight costs on long-distance commutes.

Tracking of Arctic terns Sterna paradisaea reveals longest animal migration

PubMed Central

Egevang, Carsten; Stenhouse, Iain J.; Phillips, Richard A.; Petersen, Aevar; Fox, James W.; Silk, Janet R. D.

2010-01-01

The study of long-distance migration provides insights into the habits and performance of organisms at the limit of their physical abilities. The Arctic tern Sterna paradisaea is the epitome of such behavior; despite its small size (<125 g), banding recoveries and at-sea surveys suggest that its annual migration from boreal and high Arctic breeding grounds to the Southern Ocean may be the longest seasonal movement of any animal. Our tracking of 11 Arctic terns fitted with miniature (1.4-g) geolocators revealed that these birds do indeed travel huge distances (more than 80,000 km annually for some individuals). As well as confirming the location of the main wintering region, we also identified a previously unknown oceanic stopover area in the North Atlantic used by birds from at least two breeding populations (from Greenland and Iceland). Although birds from the same colony took one of two alternative southbound migration routes following the African or South American coast, all returned on a broadly similar, sigmoidal trajectory, crossing from east to west in the Atlantic in the region of the equatorial Intertropical Convergence Zone. Arctic terns clearly target regions of high marine productivity both as stopover and wintering areas, and exploit prevailing global wind systems to reduce flight costs on long-distance commutes. PMID:20080662

Avian Influenza Virus (H11N9) in Migratory Shorebirds Wintering in the Amazon Region, Brazil

PubMed Central

de Araujo, Jansen; de Azevedo Júnior, Severino M.; Gaidet, Nicolas; Hurtado, Renata F.; Walker, David; Thomazelli, Luciano M.; Ometto, Tatiana; Seixas, Marina M. M.; Rodrigues, Roberta; Galindo, Daniele B.; da Silva, Adriana C. S.; Rodrigues, Arlinéa M. M.; Bomfim, Leonardo L.; Mota, Marcelo A.; Larrazábal, Maria E.; Branco, Joaquim O.; Serafini, Patricia; Neto, Isaac S.; Franks, John; Webby, Richard J.; Webster, Robert G.; Durigon, Edison L.

2014-01-01

Aquatic birds are the natural reservoir for avian influenza viruses (AIV). Habitats in Brazil provide stopover and wintering sites for water birds that migrate between North and South America. The current study was conducted to elucidate the possibility of the transport of influenza A viruses by birds that migrate annually between the Northern and Southern Hemispheres. In total, 556 orotracheal/cloacal swab samples were collected for influenza A virus screening using real-time RT-PCR (rRT-PCR). The influenza A virus-positive samples were subjected to viral isolation. Four samples were positive for the influenza A matrix gene by rRT-PCR. From these samples, three viruses were isolated, sequenced and characterized. All positive samples originated from a single bird species, the ruddy turnstone (Arenaria interpres), that was caught in the Amazon region at Caeté Bay, Northeast Pará, at Ilha de Canelas. To our knowledge, this is the first isolation of H11N9 in the ruddy turnstone in South America. PMID:25329399

Using Autumn Hawk Watch to track raptor migration and to monitor populations of North American birds of prey

Treesearch

Kyle McCarty; Keith L. Bildstein

2005-01-01

Raptors are secretive, area-sensitive predators whose populations can be logistically difficult and financially prohibitive to monitor. Many North American populations of raptors are migratory however, and on migration raptors are frequently counted at traditional migration watchsites. Experiences at Hawk Mountain Sanctuary (HMS) and elsewhere suggest that long-term...

Insights into Wilson's Warbler migration from analyses of hydrogen stable-isotope ratios

Treesearch

Jeffrey F. Kelly; Viorel Atudorei; Zachary D. Sharp; Deborah M. Finch

2002-01-01

Our ability to link the breeding locations of individual passerines to migration stopover sites and wintering locations is limited. Stable isotopes of hydrogen contained in bird feathers have recently shown potential in this regard. We measured hydrogen stable-isotope ratios (deltaD) of feathers from breeding, migrating, and wintering Wilson's Warblers. Analyses...

Matching times of leading and following suggest cooperation through direct reciprocity during V-formation flight in ibis

PubMed Central

Voelkl, Bernhard; Portugal, Steven J.; Unsöld, Markus; Usherwood, James R.; Wilson, Alan M.; Fritz, Johannes

2015-01-01

One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front? To investigate how this dilemma is solved, we studied the flight behavior of a flock of juvenile Northern bald ibis (Geronticus eremita) during a human-guided autumn migration. We could show that the amount of time a bird is leading a formation is strongly correlated with the time it can itself profit from flying in the wake of another bird. On the dyadic level, birds match the time they spend in the wake of each other by frequent pairwise switches of the leading position. Taken together, these results suggest that bald ibis cooperate by directly taking turns in leading a formation. On the proximate level, we propose that it is mainly the high number of iterations and the immediacy of reciprocation opportunities that favor direct reciprocation. Finally, we found evidence that the animals' propensity to reciprocate in leading has a substantial influence on the size and cohesion of the flight formations. PMID:25646487

Matching times of leading and following suggest cooperation through direct reciprocity during V-formation flight in ibis.

PubMed

Voelkl, Bernhard; Portugal, Steven J; Unsöld, Markus; Usherwood, James R; Wilson, Alan M; Fritz, Johannes

2015-02-17

One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front? To investigate how this dilemma is solved, we studied the flight behavior of a flock of juvenile Northern bald ibis (Geronticus eremita) during a human-guided autumn migration. We could show that the amount of time a bird is leading a formation is strongly correlated with the time it can itself profit from flying in the wake of another bird. On the dyadic level, birds match the time they spend in the wake of each other by frequent pairwise switches of the leading position. Taken together, these results suggest that bald ibis cooperate by directly taking turns in leading a formation. On the proximate level, we propose that it is mainly the high number of iterations and the immediacy of reciprocation opportunities that favor direct reciprocation. Finally, we found evidence that the animals' propensity to reciprocate in leading has a substantial influence on the size and cohesion of the flight formations.

Hyalomma ticks on northward migrating birds in southern Spain: Implications for the risk of entry of Crimean-Congo haemorrhagic fever virus to Great Britain.

PubMed

England, Marion E; Phipps, Paul; Medlock, Jolyon M; Atkinson, Peter M; Atkinson, Barry; Hewson, Roger; Gale, Paul

2016-06-01

Crimean-Congo haemorrhagic fever virus (CCHFV) is a zoonotic virus transmitted by Hyalomma ticks, the immature stages of which may be carried by migratory birds. In this study, a total of 12 Hyalomma ticks were recovered from five of 228 migratory birds trapped in Spring, 2012 in southern Spain along the East Atlantic flyway. All collected ticks tested negative for CCHFV. While most birds had zero Hyalomma ticks, two individuals had four and five ticks each and the statistical distribution of Hyalomma tick counts per bird is over-dispersed compared to the Poisson distribution, demonstrating the need for intensive sampling studies to avoid underestimating the total number of ticks. Rates of tick exchange on migratory birds during their northwards migration will affect the probability that a Hyalomma tick entering Great Britain is positive for CCHFV. Drawing on published data, evidence is presented that the latitude of a European country affects the probability of entry of Hyalomma ticks on wild birds. Further data on Hyalomma infestation rates and tick exchange rates are required along the East Atlantic flyway to further our understanding of the origin of Hyalomma ticks (i.e., Africa or southern Europe) and hence the probability of entry of CCHFV into GB. © 2016 The Society for Vector Ecology.

A Preliminary Investigation on Ticks (Acari: Ixodidae) Infesting Birds in Kızılırmak Delta, Turkey.

PubMed

Keskin, Adem; Erciyas-Yavuz, Kiraz

2016-01-01

Ticks are mandatory blood-feeding ectoparasites of mammals, birds, reptiles, and even amphibians. Turkey has a rich bird fauna and is located on the main migration route for many birds. However, information on ticks infesting birds is very limited. In the present study, we aimed to determine ticks infesting birds in Kızılırmak Delta, Turkey. In 2014 autumn bird migration season, a total of 7,452 birds belonging to 79 species, 52 genera, 35 families, and 14 orders were examined for tick infestation. In total, 287 (234 larvae, 47 nymphs, 6♀) ticks were collected from 54 passerine birds (prevalence = 0.72%) belonging to 12 species. Ticks were identified as Amblyomma sp., Dermacentor marginatus (Sulzer), Haemaphysalis concinna Koch, Haemaphysalis punctata Canestrini and Fanzago, Hyalomma sp., Ixodes frontalis (Panzer), and Ixodes ricinus (L). The most common tick species were I. frontalis (223 larvae, 23 nymphs, 6♀) followed by I. ricinus (3 larvae, 12 nymphs) and H. concinna (4 larvae, 6 nymphs). Based on our results, it can be said that Erithacus rubecula (L.) is the main host of immature I. frontalis, whereas Turdus merula L. is the most important carrier of immature stages of some ticks in Kızılırmak Delta, Turkey. To the best of our knowledge, most of the tick-host associations found in this study have never been documented in the literature. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Homing pigeons externally exposed to Deepwater Horizon crude oil change flight performance and behavior.

PubMed

Perez, Cristina R; Moye, John K; Cacela, Dave; Dean, Karen M; Pritsos, Chris A

2017-11-01

The Deepwater Horizon oil spill was the largest in U.S. history, contaminating thousands of miles of coastal habitat and affecting the lives of many avian species. The Gulf of Mexico is a critical bird migration route area and migrants that were oiled but did not suffer mortality as a direct result of the spill faced unpredictable fates. This study utilized homing pigeons as a surrogate species for migratory birds to investigate the effects a single low level external oiling event has on the flight performance and behavior of birds flying repeated 161 km flights. Data from GPS data loggers showed that lightly oiled pigeons changed their flight paths, increased their flight durations by 2.6 fold, increased their flight distances by 28 km and subsequently decreased their route efficiencies. Oiled birds also exhibited reduced rate of weight gain between flights. Our data suggest that contaminated birds surviving the oil spill may have experienced flight impairment and reduced refueling abilities, likely reducing overall migration speed. Our findings contribute new information on how oil spills affect avian species, as the effects of oil on the flight behavior of long distance free-flying birds have not been previously described. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energy Expenditure and Metabolic Changes of Free-Flying Migrating Northern Bald Ibis.

PubMed

Bairlein, Franz; Fritz, Johannes; Scope, Alexandra; Schwendenwein, Ilse; Stanclova, Gabriela; van Dijk, Gertjan; Meijer, Harro A J; Verhulst, Simon; Dittami, John

2015-01-01

Many migrating birds undertake extraordinary long flights. How birds are able to perform such endurance flights of over 100-hour durations is still poorly understood. We examined energy expenditure and physiological changes in Northern Bald Ibis Geronticus eremite during natural flights using birds trained to follow an ultra-light aircraft. Because these birds were tame, with foster parents, we were able to bleed them immediately prior to and after each flight. Flight duration was experimentally designed ranging between one and almost four hours continuous flights. Energy expenditure during flight was estimated using doubly-labelled-water while physiological properties were assessed through blood chemistry including plasma metabolites, enzymes, electrolytes, blood gases, and reactive oxygen compounds. Instantaneous energy expenditure decreased with flight duration, and the birds appeared to balance aerobic and anaerobic metabolism, using fat, carbohydrate and protein as fuel. This made flight both economic and tolerable. The observed effects resemble classical exercise adaptations that can limit duration of exercise while reducing energetic output. There were also in-flight benefits that enable power output variation from cruising to manoeuvring. These adaptations share characteristics with physiological processes that have facilitated other athletic feats in nature and might enable the extraordinary long flights of migratory birds as well.

Re-calibration of the magnetic compass in hand-raised European robins (Erithacus rubecula)

PubMed Central

Alert, Bianca; Michalik, Andreas; Thiele, Nadine; Bottesch, Michael; Mouritsen, Henrik

2015-01-01

Migratory birds can use a variety of environmental cues for orientation. A primary calibration between the celestial and magnetic compasses seems to be fundamental prior to a bird’s first autumn migration. Releasing hand-raised or rescued young birds back into the wild might therefore be a problem because they might not have established a functional orientation system during their first calendar year. Here, we test whether hand-raised European robins that did not develop any functional compass before or during their first autumn migration could relearn to orient if they were exposed to natural celestial cues during the subsequent winter and spring. When tested in the geomagnetic field without access to celestial cues, these birds could orient in their species-specific spring migratory direction. In contrast, control birds that were deprived of any natural celestial cues throughout remained unable to orient. Our experiments suggest that European robins are still capable of establishing a functional orientation system after their first autumn. Although the external reference remains speculative, most likely, natural celestial cues enabled our birds to calibrate their magnetic compass. Our data suggest that avian compass systems are more flexible than previously believed and have implications for the release of hand-reared migratory birds. PMID:26388258

Energy Expenditure and Metabolic Changes of Free-Flying Migrating Northern Bald Ibis

PubMed Central

Bairlein, Franz; Fritz, Johannes; Scope, Alexandra; Schwendenwein, Ilse; Stanclova, Gabriela; van Dijk, Gertjan; Meijer, Harro A. J.; Verhulst, Simon

2015-01-01

Many migrating birds undertake extraordinary long flights. How birds are able to perform such endurance flights of over 100-hour durations is still poorly understood. We examined energy expenditure and physiological changes in Northern Bald Ibis Geronticus eremite during natural flights using birds trained to follow an ultra-light aircraft. Because these birds were tame, with foster parents, we were able to bleed them immediately prior to and after each flight. Flight duration was experimentally designed ranging between one and almost four hours continuous flights. Energy expenditure during flight was estimated using doubly-labelled-water while physiological properties were assessed through blood chemistry including plasma metabolites, enzymes, electrolytes, blood gases, and reactive oxygen compounds. Instantaneous energy expenditure decreased with flight duration, and the birds appeared to balance aerobic and anaerobic metabolism, using fat, carbohydrate and protein as fuel. This made flight both economic and tolerable. The observed effects resemble classical exercise adaptations that can limit duration of exercise while reducing energetic output. There were also in-flight benefits that enable power output variation from cruising to manoeuvring. These adaptations share characteristics with physiological processes that have facilitated other athletic feats in nature and might enable the extraordinary long flights of migratory birds as well. PMID:26376193

Herbarium specimens show patterns of fruiting phenology in native and invasive plant species across New England.

PubMed

Gallinat, Amanda S; Russo, Luca; Melaas, Eli K; Willis, Charles G; Primack, Richard B

2018-01-01

Patterns of fruiting phenology in temperate ecosystems are poorly understood, despite the ecological importance of fruiting for animal nutrition and seed dispersal. Herbarium specimens represent an under-utilized resource for investigating geographical and climatic factors affecting fruiting times within species, patterns in fruiting times among species, and differences between native and non-native invasive species. We examined over 15,000 herbarium specimens, collected and housed across New England, and found 3159 specimens with ripe fruits, collected from 1849-2013. We examined patterns in fruiting phenology among 37 native and 18 invasive woody plant species common to New England. We compared fruiting dates between native and invasive species, and analyzed how fruiting phenology varies with temperature, space, and time. Spring temperature and year explained a small but significant amount of the variation in fruiting dates. Accounting for the moderate phylogenetic signal in fruiting phenology, invasive species fruited 26 days later on average than native species, with significantly greater standard deviations. Herbarium specimens can be used to detect patterns in fruiting times among species. However, the amount of intraspecific variation in fruiting times explained by temporal, geographic, and climatic predictors is small, due to a combination of low temporal resolution of fruiting specimens and the protracted nature of fruiting. Later fruiting times in invasive species, combined with delays in autumn bird migrations in New England, may increase the likelihood that migratory birds will consume and disperse invasive seeds in New England later into the year. © 2018 Botanical Society of America.

Use of multiple modes of flight subsidy by a soaring terrestrial bird, the golden eagle Aquila chrysaetos, when on migration

PubMed Central

Katzner, Todd E.; Turk, Philip J.; Duerr, Adam E.; Miller, Tricia A.; Lanzone, Michael J.; Cooper, Jeff L.; Brandes, David; Tremblay, Junior A.; Lemaître, Jérôme

2015-01-01

Large birds regularly use updrafts to subsidize flight. Although most research on soaring bird flight has focused on use of thermal updrafts, there is evidence suggesting that many species are likely to use multiple modes of subsidy. We tested the degree to which a large soaring species uses multiple modes of subsidy to provide insights into the decision-making that underlies flight behaviour. We statistically classified more than 22 000 global positioning satellite–global system for mobile communications telemetry points collected at 30-s intervals to identify the type of subsidized flight used by 32 migrating golden eagles during spring in eastern North America. Eagles used subsidized flight on 87% of their journey. They spent 41.9% ± 1.5 (, range: 18–56%) of their subsidized northbound migration using thermal soaring, 45.2% ± 2.1 (12–65%) of time gliding between thermals, and 12.9% ± 2.2 (1–55%) of time using orographic updrafts. Golden eagles responded to the variable local-scale meteorological events they encountered by switching flight behaviour to take advantage of multiple modes of subsidy. Orographic soaring occurred more frequently in morning and evening, earlier in the migration season, and when crosswinds and tail winds were greatest. Switching between flight modes allowed migration for relatively longer periods each day and frequent switching behaviour has implications for a better understanding of avian flight behaviour and of the evolution of use of subsidy in flight. PMID:26538556

A statistical framework for genetic association studies of power curves in bird flight

PubMed Central

Lin, Min; Zhao, Wei

2006-01-01

How the power required for bird flight varies as a function of forward speed can be used to predict the flight style and behavioral strategy of a bird for feeding and migration. A U-shaped curve was observed between the power and flight velocity in many birds, which is consistent to the theoretical prediction by aerodynamic models. In this article, we present a general genetic model for fine mapping of quantitative trait loci (QTL) responsible for power curves in a sample of birds drawn from a natural population. This model is developed within the maximum likelihood context, implemented with the EM algorithm for estimating the population genetic parameters of QTL and the simplex algorithm for estimating the QTL genotype-specific parameters of power curves. Using Monte Carlo simulation derived from empirical observations of power curves in the European starling (Sturnus vulgaris), we demonstrate how the underlying QTL for power curves can be detected from molecular markers and how the QTL detected affect the most appropriate flight speeds used to design an optimal migration strategy. The results from our model can be directly integrated into a conceptual framework for understanding flight origin and evolution. PMID:17066123

Correlating Flight Behavior and Radar Measurements for Species Based Classification of Bird Radar Echoes for Wind Energy Site Assessment

NASA Astrophysics Data System (ADS)

Werth, S. P.; Frasier, S. J.

2015-12-01

Wind energy is one of the fastest-growing segments of the world energy market, offering a clean and abundant source of electricity. However, wind energy facilities can have detrimental effects on wildlife, especially birds and bats. Monitoring systems based on marine navigation radar are often used to quantify migration near potential wind sites, but the ability to reliably distinguish between bats and different varieties of birds has not been practically achieved. This classification capability would enable wind site selection that protects more vulnerable species, such as bats and raptors. Flight behavior, such as wing beat frequency, changes in speed, or changes in orientation, are known to vary by species [1]. The ability to extract these properties from radar data could ultimately enable a species based classification scheme. In this work, we analyze the relationship between radar measurements and bird flight behavior in echoes from avifauna. During the 2014 fall migration season, the UMass dual polarized weather radar was used to collect low elevation observations of migrating birds as they traversed through a fixed antenna beam. The radar was run during the night time, in clear-air conditions. Data was coherently integrated, and detections of biological targets exceeding an SNR threshold were extracted. Detections without some dominant frequency content (i.e. clear periodicity, potentially the wing beat frequency) were removed from the sample in order to isolate observations suspected to contain a single species or bird. For the remaining detections, measurements including the polarimetric products and the Doppler spectrum were extracted at each time step over the duration of the observation. The periodic and time changing nature of some of these different measurements was found to have a strong correlation with flight behavior (i.e. flapping vs. gliding behavior). Assumptions about flight behavior and orientation were corroborated through scattering simulations of birds in flight. The presence of a strong correlation between certain radar measurements and flight behavior would suggest the potential for a broad, species based avian classification algorithm. Such a classification scheme could ultimately help select and monitor wind sites in order to minimize harm to at-risk bird and bat species.

Seasonal relationships between birds and arthropods in bottomland forest canopy gaps.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowen, Liessa, Thomas

2004-12-31

Bowen, Liessa, Thomas. 2004. Seasonal relationships between birds and arthropods in bottomland forest canopy gaps. PhD Dissertation. North Carolina State University. Raleigh, North Carolina. 98pp. I investigated the influence of arthropod availability and vegetation structure on avian habitat use at the center, edge, and adjacent to forest canopy gaps in 2001 and 2002. I used mist-netting and plot counts to estimate abundance of birds using three sizes (0.13, 0.26, and 0.5 ha) of 7-8 year old group-selection timber harvest openings during four seasons (spring migration, breeding, post-breeding, and fall migration) in a bottomland hardwood forest in the Upper Coastal Plainmore » of South Carolina. I used foliage clipping, Malaise trapping, and pitfall trapping to determine arthropod abundance within each habitat, and I used a warm water crop-flush on captured birds to gather information about arthropods eaten. I observed more birds, including forest interior species, forest-edge spedge species, and several individual species, in early-successional canopy gap and gap-edge habitats than in surrounding mature forest during all seasons. I found a significant interaction between season and habitat type for several groups and individual species, suggesting a seasonal shift in habitat use. Captures of all birds, insectivorous birds, foliage- gleaners, ground-gleaners, aerial salliers, Hooded Warbler (Wilsonia citrina), Northern Cardinal (Cardinalis cardinalis), White-eyed Vireo (Vireo griseus), and Black-throated Blue Warbler (Dendroica caerulescens) were positively correlated with understory vegetation density during two or more seasons. I found relationships between insectivorous birds and leaf-dwelling Lepidoptera, insectivorous birds and ground-dwelling arthropods, foliage-gleaning birds and foliage-dwelling arthropods, and aerial salliers and flying arthropods, as well as between individual bird species and arthropods. Relationships were inconsistent, however, with many species being negatively correlated with arthropod abundance. Coleopteran, Lepidopteran, and Aranid prey items represented the greatest proportions of crop-flush samples during all seasons. Proportional consumption of Coleopteran and Hemipteran prey items was higher than their proportional availability, and consumption of Aranid and Hymenopteran prey items was lower than their proportional availability during all seasons. Individual bird species and guilds consistently consumed similar proportions of certain groups of arthropods from spring through fall migration, with no apparent seasonal shift in diet composition. My research suggests that many species of birds selectively choose mid-successional gap and gap-edge habitat over surrounding mature forest during the non-breeding season, and the creation of small canopy gaps within a mature forest may increase local bird species richness. It is less obvious how arthropod availability affects bird habitat use across seasons. A structurally diverse mosaic of habitat types, including regenerating canopy gaps within a mature forest, may provide valuable habitat for birds and a variety of arthropod prey items across multiple seasons.« less

KSC-99pp0258

NASA Image and Video Library

1999-03-01

KENNEDY SPACE CENTER, FLA. -- A pair of willets soars to a landing among a flock of short-billed dowitchers on a grassy mound in the shallow waters of the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Willets are best identified in flight by their black-and-white wing pattern. They breed in southern Canada, the United States and the West Indies, wintering from the southern U.S. to central South America. The dowitchers' range is southern Alaska to eastern Canada, and they also winter from the southern United States to central South America. They often frequent coastal flats during migrations. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds

Understanding the stopover of migratory birds: a scale dependent approach

Treesearch

Frank R. Moore; Mark S. Woodrey; Jeffrey J. Buler; Stefan Woltmann; Ted R. Simons

2005-01-01

The development of comprehensive conservation strategies and management plans for migratory birds depends on understanding migrant-habitat relations throughout the annual cycle, including the time when migrants stopover en route. Yet, the complexity of migration makes the assessment of habitat requirements and development of a comprehensive...

Highly pathogenic avian influenza virus among wild birds in Mongolia

USDA-ARS?s Scientific Manuscript database

The central Asian country of Mongolia supports large populations of migratory water birds that migrate across much of Asia where highly pathogenic avian influenza (HPAI) virus subtype H5N1 is endemic. This, together with the near absence of domestic poultry, makes Mongolia an ideal location to unde...

High altitude flights by ruddy shelduck Tadorna ferruginea during trans-Himalayan migrations

USGS Publications Warehouse

Parr, N.; Bearhop, S.; Douglas, David C.; Takekawa, J.Y.; Prosser, Diann J.; Newman, S.H.; Perry, W.M.; Balachandran, S.; Witt, M.J.; Hou, Y.; Luo, Z.; Hawkes, L.A.

2017-01-01

Birds that migrate across high altitude mountain ranges are faced with the challenge of maintaining vigorous exercise in environments with limited oxygen. Ruddy shelducks are known to use wintering grounds south of the Tibetan Plateau at sea level and breeding grounds north of Himalayan mountain range. Therefore, it is likely these shelducks are preforming high altitude migrations. In this study we analyse satellite telemetry data collected from 15 ruddy shelduck from two populations wintering south of the Tibetan Plateau from 2007 to 2011. During north and south migrations ruddy shelduck travelled 1481 km (range 548–2671 km) and 1238 km (range 548–2689 km) respectively. We find mean maximum altitudes of birds in flight reached 5590 m (range of means 4755–6800 m) and mean maximum climb rates of 0.45 m s–1 (range 0.23–0.74 m s–1). The ruddy shelduck is therefore an extreme high altitude migrant that has likely evolved a range of physiological adaptations in order to complete their migrations.

Satellite-marked waterfowl reveal migratory connection between H5N1 outbreak areas in China and Mongolia

USGS Publications Warehouse

Prosser, D.J.; Takekawa, John Y.; Newman, S.H.; Yan, B.; Douglas, David C.; Hou, Y.; Xing, Z.; Zhang, Dongxiao; Li, T.; Li, Y.; Zhao, D.; Perry, W.M.; Palm, E.C.

2009-01-01

The role of wild birds in the spread of highly pathogenic avian influenza H5N1 has been greatly debated and remains an unresolved question. However, analyses to determine involvement of wild birds have been hindered by the lack of basic information on their movements in central Asia. Thus, we initiated a programme to document migrations of waterfowl in Asian flyways to inform hypotheses of H5N1 transmission. As part of this work, we studied migration of waterfowl from Qinghai Lake, China, site of the 2005 H5N1 outbreak in wild birds. We examined the null hypothesis that no direct migratory connection existed between Qinghai Lake and H5N1 outbreak areas in central Mongolia, as suggested by some H5N1 phylogeny studies. We captured individuals in 2007 from two of the species that died in the Qinghai Lake outbreaks and marked them with GPS satellite transmitters: Bar-headed Geese Anser indicus (n = 14) and Ruddy Shelduck Tadorna ferruginea (n = 11). Three of 25 marked birds (one Goose and two Shelducks) migrated to breeding grounds near H5N1 outbreak areas in Mongolia. Our results describe a previously unknown migratory link between the two regions and offer new critical information on migratory movements in the region. ?? 2009 British Ornithologists' Union.

Disentangling migratory routes and wintering grounds of Iberian near-threatened European Rollers Coracias garrulus.

PubMed

Rodríguez-Ruiz, Juan; de la Puente, Javier; Parejo, Deseada; Valera, Francisco; Calero-Torralbo, Miguel A; Reyes-González, José M; Zajková, Zuzana; Bermejo, Ana; Avilés, Jesús M

2014-01-01

Long-distance migrants are suffering drastic declines in the last decades. Causes beneath this problem are complex due to the wide spatial and temporal scale involved. We aim to reveal migratory routes, stopover areas, wintering grounds, and migratory strategies for the most southwestern populations of the near-threatened European Roller Coracias garrulus in order to identify conservation key areas for the non-breeding stage of this species. To this end, we used tracking data from seven satellite transmitters fitted to birds breeding in different populations throughout the Iberian Peninsula and four geolocators fitted to individuals in a southeastern Iberian population. Precise satellite data were used to describe daily activity patterns and speed in relation to the main regions crossed during the migration. Individuals from the most southwestern Iberian populations made a detour towards the Atlantic African coast whereas those from northeastern populations followed a straight north-to-south route. We identified important stopover areas in the Sahel belt, mainly in the surroundings of the Lake Chad, and wintering grounds on southwestern Africa farther west than previously reported for the species. Concerning the migratory strategy, satellite data revealed: 1) a mainly nocturnal flying activity, 2) that migration speed depended on the type of crossed habitat, with higher average speed while crossing the desert; and 3) that the migration was slower and lasted longer in autumn than in spring. The studied populations showed weak migratory connectivity, suggesting the confluence of birds from a wide range of breeding grounds in a restricted wintering area. Therefore, we suggest to target on defining precisely key areas for this species and identifying specific threats in them in order to develop an appropriate global conservation programme for the European Roller.

Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific

USGS Publications Warehouse

Gill, Robert E.; Douglas, David C.; Handel, Colleen M.; Tibbitts, T. Lee; Hufford, Gary; Piersma, Theunis

2014-01-01

The annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop flights of a week's duration or longer. At a minimum, their decisions will affect wind profitability and thus reduce energetic costs of migration; in the extreme, poor decisions or unpredictable weather events will risk survival. We used satellite telemetry to track the annual migration of 24 bar-tailed godwits and analysed their flight performance relative to wind conditions during three major migration legs between nonbreeding grounds in New Zealand and breeding grounds in Alaska. Because flight altitudes of birds en route were unknown, we modelled flight efficiency at six geopotential heights across each migratory segment. Birds selected departure dates when atmospheric conditions conferred the greatest wind assistance both at departure and throughout their flights. This behaviour suggests that there exists a cognitive mechanism, heretofore unknown among migratory birds, that allows godwits to assess changes in weather conditions that are linked (i.e. teleconnected) across widely separated atmospheric regions. Godwits also showed adaptive flexibility in their response not only to cues related to seasonal changes in macrometeorology, such as spatial shifting of storm tracks and temporal periods of cyclogenesis, but also to cues associated with stochastic events, especially at departure sites. Godwits showed limits to their response behaviours, however, especially relative to rapidly developing stochastic events while en route. We found that flight efficiency depended significantly upon altitude and hypothesize that godwits exhibit further adaptive flexibility by varying flight altitude en route to optimize flight efficiency.

Morphological constraints on changing avian migration phenology.

PubMed

Møller, A P; Rubolini, D; Saino, N

2017-06-01

Many organisms at northern latitudes have responded to climate warming by advancing their spring phenology. Birds are known to show earlier timing of spring migration and reproduction in response to warmer springs. However, species show heterogeneous phenological responses to climate warming, with those that have not advanced or have delayed migration phenology experiencing population declines. Although some traits (such as migration distance) partly explain heterogeneity in phenological responses, the factors affecting interspecies differences in the responsiveness to climate warming have yet to be fully explored. In this comparative study, we investigate whether variation in wing aspect ratio (reflecting relative wing narrowness), an ecomorphological trait that is strongly associated with flight efficiency and migratory behaviour, affects the ability to advance timing of spring migration during 1960-2006 in a set of 80 European migratory bird species. Species with larger aspect ratio (longer and narrower wings) showed smaller advancement of timing of spring migration compared to species with smaller aspect ratio (shorter and wider wings) while controlling for phylogeny, migration distance and other life-history traits. In turn, migration distance positively predicted aspect ratio across species. Hence, species that are better adapted to migration appear to be more constrained in responding phenologically to rapid climate warming by advancing timing of spring migration. Our findings corroborate the idea that aspect ratio is a major evolutionary correlate of migration, and suggest that selection for energetically efficient flights, as reflected by high aspect ratio, may hinder phenotypically plastic/microevolutionary adjustments of migration phenology to ongoing climatic changes. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Conceptual ecological model for management of breeding shrubland birds in the Mid-Atlantic Region

USGS Publications Warehouse

Peterjohn, Bruce G.

2006-01-01

While grassland birds have become the focus of increased conservation activities, the status of birds occupying shrubland habitats has received relatively little attention (Hunter et al. 2001). Yet, in eastern North America, shrubland birds exhibited consistent population declines during the past 40 years, based on data from the North American Breeding Bird Survey (Pardieck and Sauer 2001). These population declines primarily reflect large-scale changes in land use patterns during the previous century (Lorimer 2001). Large areas of marginal farmland were abandoned and underwent secondary succession during the first half of the twentieth century, producing abundant successional habitats favored by shrubland birds. As these habitats matured, combined with strict fire-suppression policies (Hunter et al. 2001), shrublands succeeded into mature forests, and shrubland bird communities were replaced by woodland birds (Irland 1982; Askins 1993). For example, while nearly 29% of New England forests were classified as sapling stage in 1950, only 8% remained at that stage in the 1980s (Askins 1993). The trend towards forest maturation and loss of shrubland habitats continues, yet concerted conservation activities have not been directed to benefit declining shrubland bird populations. The National Park Service (NPS) could contribute to shrubland bird conservation in the Mid- Atlantic Region. The NPS maintains a number of historic sites and former battlefields managed for their cultural significance but also support wildlife populations. Many of these “cultural parks” maintain open landscapes, recreating land use patterns existing at the times of the historical events. While these open landscapes are frequently managed grasslands, some parks also support successional habitats that could be managed to benefit shrubland birds. In 2005, the NPS initiated a project exploring the potential of “cultural parks” to support significant breeding grassland and shrubland bird communities. This project involved parks within three NPS Inventory and Monitoring Program (I&M) networks, Mid-Atlantic, National Capital, and Eastern Rivers and Mountains. Five parks were selected for the initial focus of this study, all of which maintain open landscapes for interpreting historic events. Most parks were selected because they contain the most extensive grassland habitats within their networks, although some also support shrubby successional habitats. The five parks included in this study are Antietam National Battlefield, Fort Necessity National Battlefield, Gettysburg National Battlefield, Manassas National Battlefield, and Monocacy National Battlefield. This conceptual ecological model is one product of this project. The information presented below allows NPS network coordinators to understand which factors should be considered when making decisions concerning shrubland management within their networks. This model provides park resource managers with information on shrubland ecology in the Mid-Atlantic Region, the ecological requirements of shrubland birds likely to occur in their parks, and management issues influencing whether significant breeding populations can occupy shrublands created and maintained in the parks. Resource managers can then make informed decisions concerning their ability to create and maintain shrubland habitats. The emphasis of this conceptual model is restricted to management of breeding shrubland birds. Additional species occur during migration and winter, and habitat requirements of shrubland birds during nonbreeding seasons may differ from those described for the breeding season.

Utilization Patterns of Intertidal Habitats by Birds in Yaquina Estuary, Oregon

EPA Science Inventory

Bird utilization patterns were assessed in five types of intertidal soft sediment and low marsh habitat in the Yaquina estuary, Oregon. Censuses were designed to determine the spatial and seasonal utilization patterns of birds in Zostera marina (eelgrass), Upogebia (mud shrimp)/...

Local site variation in stopover physiology of migrating songbirds near the south shore of Lake Ontario is linked to fruit availability and quality

PubMed Central

Smith, Susan B.; Miller, Allyson C.; Merchant, Charmaine R.; Sankoh, Amie F.

2015-01-01

Birds that migrate long distances between breeding and wintering grounds are challenged to find adequate stopover sites that can provide a high-quality source of nutrition in order to refuel quickly and continue on their migratory journeys. Wild fruits are a well-documented component in the diets of many passerines during autumn migration. Thus, fruit availability and the proliferation of shrubs that bear low-quality fruits at important stopover sites may dictate the quality of food resources available for refuelling birds and present a conservation concern. We profiled plasma metabolites of two migratory passerine species at two different stopover sites near the south shore of Lake Ontario during the peak of autumn migration. We also measured diversity, availability and nutritional quality of fruits present at these sites. Site explained most of the variation in plasma triglyceride for both bird species, but was less important than other confounding variables for explaining concentrations of plasma β-hydroxybutyrate and plasma uric acid concentrations. Site differences in fat deposition, as indicated by plasma triglyceride, may in part be explained by the large differences in diversity and availability of high-quality fruits between the two sites. Our results suggest that abundant, lipid-rich native fruits with high-energy density are associated with increased fat deposition during autumn stopovers for some species, although other factors, such as proximity to the Lake Ontario shoreline and the opportunities to refuel in the surrounding landscape, are likely to play a role in stopover site use by birds. It is possible that local site characteristics that influence growing conditions may impact the quality of fruits produced by a plant species, altering the availability of critical nutrients for avian consumers. PMID:27293721

2014-2016 Avian Point Count and Migration Surveys at Site 300 for the Lawrence Livermore National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fratanduono, M.

The primary goals of the surveys were to: 1) collect minutes of bird activity within Site 300, 2) consider relative abundance of the different bird species occurring within the Site, 3) collect behavioral information, and 4) provide compelling evidence to determine the status of the Site as a migration corridor or migration stopover site. To this end, two survey types were conducted: avian point counts were conducted on a monthly basis from February 2014 through January 2016 and migration surveys were conducted over two three-month periods from September 2014 through November 2014, and September 2015 through November 2015. These twomore » surveys types provided the opportunity to observe avian species in a variety of conditions across a two year period. Whenever possible or relevant, the observations of either survey were used to inform and complement the observations of the other survey in pursuit of the above goals. Both survey types are described below.« less

An assessment of spatio-temporal relationships between nocturnal bird migration traffic rates and diurnal bird stopover density.

PubMed

Horton, Kyle G; Shriver, W Gregory; Buler, Jeffrey J

2016-01-01

Daily magnitudes and fluxes of landbird migration are often measured via nocturnal traffic rates aloft or diurnal densities within terrestrial habitats during stopover. However, these measures are not consistently correlated and at times reveal opposing trends. For this reason we sought to determine how comparison methods (daily magnitude or daily flux), nocturnal monitoring tools (weather surveillance radar, WSR; thermal imaging, TI), and temporal scale (preceding or following diurnal sampling) influenced correlation strength from stopover densities estimated by daily transect counts. We quantified nocturnal traffic rates at two temporal scales; averaged across the entire night and within individual decile periods of the night, and at two spatial scales; within 1 km of airspace surrounding the site via WSR and directly overhead within the narrow beam of a TI. Overall, the magnitude of daily bird density during stopover was positively related to the magnitude of broad-scale radar traffic rates of migrants on preceding and following nights during both the spring and fall. These relationships were strongest on the following night, and particularly from measures early in the night. Only during the spring on the following nights did we find positive correlations between the daily flux of transect counts and migration traffic rates (both WSR and TI). This indicates that our site likely had a more consistent daily turnover of migrants compared to the fall. The lack of general correlations between seasonal trends or daily flux in fine-scale TI traffic rates and stopover densities across or within nights was unexpected and likely due to poor sampling of traffic rates due to the camera's narrow beam. The order (preceding or following day) and metric of comparisons (magnitude or flux), as well as the tool (WSR or TI) used for monitoring nocturnal migration traffic can have dramatic impacts when compared with ground-based estimates of migrant density. WSR provided measures of the magnitude and daily flux in nocturnal migration traffic rates that related to daily stopover counts of migrants during spring and fall. Relationships among migrating bird flux measures are more complex than simple measures of magnitude of migration. Care should be given to address these complexities when comparing data among methods.

Experimental Evidence for Branch-to-Bird Transfer as a Mechanism for Avian Dispersal of the Hemlock Woolly Adelgid (Hemiptera: Adelgidae).

PubMed

Russo, Nicholas J; Cheah, Carole A S-J; Tingley, Morgan W

2016-10-01

Birds have long been hypothesized as primary dispersal agents of the hemlock woolly adelgid (Adelges tsugae Annand). Although A. tsugae eggs and mobile first instars (crawlers) have been collected from wild birds, key mechanistic elements necessary for avian dispersal have never been examined. To evaluate the mechanisms of bird-mediated A. tsugae dispersal, we conducted both stationary (i.e., where crawlers must actively disperse) and disturbance (i.e., where crawlers may transfer from substrates due to mechanical abrasion) dispersal trials. For stationary trials, we tested the role of perching duration, ovisac density, and seasonal timing on the rate of crawler transfer to immobile preserved bird mounts at a single site in Connecticut. For disturbance trials, we explored if transfer rates were different when branches were actively brushed against birds. Both stationary and disturbance trials resulted in successful transfers of A. tsugae to bird mounts, with disturbance trials having significantly higher rates of transfers. Crawler counts from stationary trials increased significantly with local ovisac density. Additionally, we found a nonlinear relationship between crawler transfer and experimental week, with crawler transfer highest at the beginning of sampling in May, coinciding with avian spring migration in Connecticut and the emergence of progrediens crawlers, and spiking again near 14 June, when sistens generation crawlers began to emerge. While many aspects of potential avian dispersal of A. tsugae remain unknown, these results suggest that crawler transfer to birds may occur most often when peak crawler emergence coincides with the northward migration of many small passerine bird species. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

When and where does mortality occur in migratory birds? Direct evidence from long-term satellite tracking of raptors.

PubMed

Klaassen, Raymond H G; Hake, Mikael; Strandberg, Roine; Koks, Ben J; Trierweiler, Christiane; Exo, Klaus-Michael; Bairlein, Franz; Alerstam, Thomas

2014-01-01

Information about when and where animals die is important to understand population regulation. In migratory animals, mortality might occur not only during the stationary periods (e.g. breeding and wintering) but also during the migration seasons. However, the relative importance of population limiting factors during different periods of the year remains poorly understood, and previous studies mainly relied on indirect evidence. Here, we provide direct evidence about when and where migrants die by identifying cases of confirmed and probable deaths in three species of long-distance migratory raptors tracked by satellite telemetry. We show that mortality rate was about six times higher during migration seasons than during stationary periods. However, total mortality was surprisingly similar between periods, which can be explained by the fact that risky migration periods are shorter than safer stationary periods. Nevertheless, more than half of the annual mortality occurred during migration. We also found spatiotemporal patterns in mortality: spring mortality occurred mainly in Africa in association with the crossing of the Sahara desert, while most mortality during autumn took place in Europe. Our results strongly suggest that events during the migration seasons have an important impact on the population dynamics of long-distance migrants. We speculate that mortality during spring migration may account for short-term annual variation in survival and population sizes, while mortality during autumn migration may be more important for long-term population regulation (through density-dependent effects). © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Monitoring potential geographical distribution of four wild bird species in China

NASA Astrophysics Data System (ADS)

Dai, S.; Feng, D.; Xu, B.

2015-12-01

The outbreak of highly pathogenic avian influenza (HPAI) of the H5N1 subtype in wild birds and poultry have caught worldwide attention. To explore the association between wild bird migration and avian influenza virus transmission, we monitored potential geographical distribution of four wild bird species that might carry the avian influenza viruses in China. They are Bar-headed geese (Anser indicus), Ruddy Shelduck (Tadorna ferruginea), Whooper Swan (Cygnus cygnus) and Black-headed Gull (Larus ridibundus). They served as major reservoir of the avian influenza viruses. We used bird watching records with the precise latitude/longitude coordinates from January 2002 to August 2014, and environmental variables with a pixel resolution of 5 km × 5 km from 2002 to 2014. The study utilized maximum entropy (MaxEnt) model based on ecological niche model approaches, and got the following results: 1) MaxEnt model have good discriminatory ability with the area under the curve (AUC) of the receiver operating curve (ROC) of 0.86-0.97; 2) The four wild bird species were estimated to concentrate in the North China Plain, the middle and lower region of the Yangtze River, Qinghai Lake, Tianshan Mountain and Tarim Basin, part of Tibet Plateau, and Hengduan Mountains; 3) Radiation and the minimum temperature were found to provide the most significant information. Our findings will help to understand the spread of avian influenza viruses by wild bird migration in China, which benefits for effective monitoring strategies and prevention measures.

Influence of weather conditions on the flight of migrating black storks

PubMed Central

Chevallier, D.; Handrich, Y.; Georges, J.-Y.; Baillon, F.; Brossault, P.; Aurouet, A.; Le Maho, Y.; Massemin, S.

2010-01-01

This study tested the potential influence of meteorological parameters (temperature, humidity, wind direction, thermal convection) on different migration characteristics (namely flight speed, altitude and direction and daily distance) in 16 black storks (Ciconia nigra). The birds were tracked by satellite during their entire autumnal and spring migration, from 1998 to 2006. Our data reveal that during their 27-day-long migration between Europe and Africa (mean distance of 4100 km), the periods of maximum flight activity corresponded to periods of maximum thermal energy, underlining the importance of atmospheric thermal convection in the migratory flight of the black stork. In some cases, tailwind was recorded at the same altitude and position as the birds, and was associated with a significant rise in flight speed, but wind often produced a side azimuth along the birds' migratory route. Whatever the season, the distance travelled daily was on average shorter in Europe than in Africa, with values of 200 and 270 km d−1, respectively. The fastest instantaneous flight speeds of up to 112 km h−1 were also observed above Africa. This observation confirms the hypothesis of thermal-dependant flight behaviour, and also reveals differences in flight costs between Europe and Africa. Furthermore, differences in food availability, a crucial factor for black storks during their flight between Europe and Africa, may also contribute to the above-mentioned shift in daily flight speeds. PMID:20427337

Application of ground-truth for classification and quantification of bird movements on migratory bird habitat initiative sites in southwest Louisiana: final report

USGS Publications Warehouse

Barrow, Wylie C.; Baldwin, Michael J.; Randall, Lori A.; Pitre, John; Dudley, Kyle J.

2013-01-01

This project was initiated to assess migrating and wintering bird use of lands enrolled in the Natural Resources Conservation Service’s (NRCS) Migratory Bird Habitat Initiative (MBHI). The MBHI program was developed in response to the Deepwater Horizon oil spill in 2010, with the goal of improving/creating habitat for waterbirds affected by the spill. In collaboration with the University of Delaware (UDEL), we used weather surveillance radar data (Sieges 2014), portable marine radar data, thermal infrared images, and visual observations to assess bird use of MBHI easements. Migrating and wintering birds routinely make synchronous flights near dusk (e.g., departure during migration, feeding flights during winter). Weather radars readily detect birds at the onset of these flights and have proven to be useful remote sensing tools for assessing bird-habitat relations during migration and determining the response of wintering waterfowl to wetland restoration (e.g., Wetlands Reserve Program lands). However, ground-truthing is required to identify radar echoes to species or species group. We designed a field study to ground-truth a larger-scale, weather radar assessment of bird use of MBHI sites in southwest Louisiana. We examined seasonal bird use of MBHI fields in fall, winter, and spring of 2011-2012. To assess diurnal use, we conducted total area surveys of MBHI sites in the afternoon, collecting data on bird species composition, abundance, behavior, and habitat use. In the evenings, we quantified bird activity at the MBHI easements and described flight behavior (i.e., birds landing in, departing from, circling, or flying over the MBHI tract). Our field sampling captured the onset of evening flights and spanned the period of collection of the weather radar data analyzed. Pre- and post-dusk surveys were conducted using a portable radar system and a thermal infrared camera. Landbirds, shorebirds, and wading birds were commonly found on MBHI fields during diurnal surveys in the fall. Ducks (breeding and early migrating species) were also detected on diurnal surveys, but were less abundant than the previously mentioned taxa. Wading birds were the most abundant taxa observed during evening surveys up to 5 min before dusk when their numbers declined and duck densities increased. Ducks accounted for 64.0% of all birds detected from 0-5 min before dusk. Most ducks observed at that time were flyovers (71.4%), but circling (9.2%), departing (12.1%), and landing birds (7.4%) were also detected. In fall, the portable radar system detected two peaks in bird movement: one shortly before sunset and a second shortly after dusk. The later movement began just before dusk, peaked approximately 9 min after dusk, and concluded within 20 min after dusk. The flight headings of birds changed in relation to time from dusk. In general, the majority of targets flew towards the southwest before dusk and towards the northeast after dusk. The change in flight direction pre- and post-dusk may be related to movements dominated by migratory versus local flight. In winter, ducks, shorebirds, wading birds, and landbirds were the most abundant taxa in diurnal surveys. Geese were abundant at times, but their frequency of occurrence and densities were highly variable. The majority of ducks, shorebirds, and wading birds were observed feeding in MBHI fields. Landbirds and geese were more commonly seen resting. Overwintering ducks and geese dominated the movements near dusk (95.9% of all birds ≤ 5 min pre-dusk). Ducks were more frequently observed landing in (40.8%) and flying over (33.5%) MBHI fields while geese were mainly observed circling (54.7%) and flying over (38.9%) sites. Most of the shorebirds detected Shorebirds, ducks, and wading birds were the most abundant taxa during diurnal surveys of MBHI fields in spring, and the majority of individuals were observed actively foraging rather than resting. Breeding, overwintering, and transient migrant species were all detected on MBHI fields. Near dusk, the majority of birds in flight were ducks (67.7% of all birds) that were flying over (38.2%), departing from (34.2%), or landing in (22.9%) MBHI fields. These results contrast with our winter observations when 40.8% of ducks landed in MBHI fields and 9.1% departed from fields. Portable radar and thermal camera data documented a peak in bird movements shortly after dusk, however, the peak was of lower magnitude than observed in the winter. Thermal camera data identified the birds as mostly shorebirds (57.3%) and waterfowl (40.4%). Flight headings were more variable than winter and lacked an undirectional flow. After the post-dusk movement had concluded, bird activity remained low throughout the night until approximately 30 min before dawn when a small peck in activity was observed. Flight headings during the pre-dawn were variable and multidirectional. We compared bird abundance data collected by each of our three sampling techniques (portable radar, thermal infrared camera, and direct visual observation) for the 45-min observation period immediately preceding dusk; the period when all three survey methods were used simultaneously. Abundance data from the three methods were significantly correlated at P ≤ 0.05. We documented diurnal and nocturnal bird use of MBHI fields. Most observations near dusk in winter, when weather radar data were sampled, were of ducks and geese, and in spring, shorebirds and ducks. Our winter observations show large synchronous movements of waterfowl occurring near dusk. These birds were moving to the NE and feeding in agricultural fields at night. Portable radar data suggest that birds stay in these fields through the night and make return flights near dawn.

Red List of birds of the Wadden Sea area

NASA Astrophysics Data System (ADS)

Rasmussen, L. M.; Norden Andersen, O. G.; Frikke, J.; Laursen, K.; Salvig, J.; Fleet, D. M.; Hälterlein, B.; Heckenroth, H.; Merck, T.; Rösner, H.-U.; Südbeck, P.; Wolff, W. J.; Thissen, J. B. M.

1996-10-01

350000 400000 pairs of breeding birds as well as 10 12 millions of migratory waterbirds use the Danish-German-Dutch Wadden Sea as a feeding, roosting and moulting area. The exact number of migrating birds using the Wadden Sea is unknown. 4 Wadden Sea breeding bird species are (probably) extinct in the area, e.g. Caspian Tern ( Sterna caspia) and Roseate Tern ( Sterna dougallii); the status of 5 species is critical, 4 species are endangered, the status of 6 species is vulnerable and of 4 species susceptible. Internaional responsibility can be stated for at least 15 breeding bird species or subspecies, because considerable parts of the north-west-european population (at least 5%) breed in the Wadden Sea (e.g. Eurasian Spoonbill ( Platalea leucorodia), Common Shelduck ( Tadorna tadorna), Hen Harrier ( Circus cyaneus), Avocet ( Recurvirostra avosetta), Kentish Plover ( Charadrius alexandrinus), Common Redshank ( Tringa totanus totanus), Gull-billed Tern ( Gelochelidon nilotica), Sandwich Tern ( Sterna sandvicensis), Common Tern ( Sterna hirundo), Little Tern ( Sterna albifrons). International responsibility can be determined for at least 54 migratory bird species or subspecies, because considerable parts of the biogeographical population (at least 1%) occur in the Wadden Sea during migration. Some species are present in the Wadden Sea with about 50% or nearly 90% of all individuals of the concerned populations, which means a very special international responsibility of the Wadden Sea has to be stated for these species.

Satellite tracking of two lesser spotted eagles Aquila pomarina, migrating from Namibia

USGS Publications Warehouse

Meyburg, B.-U.; Ellis, D.H.; Meyburg, C.; Mendelsohn, J.; Scheller, W.

2001-01-01

One immature and one subadult Lesser Spotted Eagle, Aquila pomarina, were followed by satellite telemetry from their non-breeding areas in Namibia. Both birds were fitted with transmitters (PTTs) in February 1994 and tracked, the immature for six months and two weeks, over distances of 10084 and 16773 km, respectively. During their time in Namibia both birds? movements were in response to good local rainfall. The immature eagle left Namibia at the end of February, the subadult at the end of March. They flew to their respective summer quarters in Hungary and the Ukraine, arriving there 2.5 and 1.5 months later than the breeding adults. The immature eagle took over two months longer on the homeward journey than a breeding male followed by telemetry in a previous study. On returning, the immature eagle followed the narrow flightpath through Africa used by other Lesser Spotted Eagles on their outward migration. It reached this corridor, which runs roughly between longitudes 31? and 36? East from Suez to Lake Tanganyika, veering from the shortest route in a direction east-northeast through Angola and Zambia to the southern end of Lake Tanganyika. The route taken by the subadult bird on its return migration differed markedly from that of all Lesser Spotted Eagles tracked to date, running further west through the Democratic Republic of Congo where, level with the equator, it flew over the eastern rainforest of that country. The outward migration, however, followed the same corridor and coincided in time with the migration of adults.

Building a Better Birdhouse

ERIC Educational Resources Information Center

Navah, Jan

2010-01-01

In a discussion about architecture, the author's students learned that architects must consider their client's needs when designing a home. To complement their study of bird migration in science class, the author decided to ask students to "think like a bird" in order to design wooden birdhouses that they could take home and actually use. This…

Serologic evidence of exposure of raptors to influenza A virus.

PubMed

Redig, Patrick T; Goyal, Sagar M

2012-06-01

Serum or plasma samples from raptors that prey or scavenge upon aquatic birds were tested by a commercially available blocking enzyme-linked immunosorbent assay for the evidence of antibodies to influenza A virus. Samples were taken from birds (n = 616) admitted to two rehabilitation centers in the United States. In addition, samples from 472 migrating peregrine falcons (Falco peregrinus) trapped on autumnal and vernal migrations for banding purposes were also tested. Only bald eagles were notably seropositive (22/406). One each of peregrine falcon, great horned owl (Bubo virginianus), and Cooper's hawk (Accipiter cooperi) from a total of 472, 81, and 100, respectively, were also positive. None of the turkey vultures (n = 21) or black vultures (n = 8) was positive. No clinical signs referable to avian influenza were seen in any bird at the time of capture. These data indicate that, among raptors, bald eagles do have exposure to influenza A viruses.

On the potential roles of ticks and migrating birds in the ecology of West Nile virus.

PubMed

Hagman, Karl; Barboutis, Christos; Ehrenborg, Christian; Fransson, Thord; Jaenson, Thomas G T; Lindgren, Per-Eric; Lundkvist, Ake; Nyström, Fredrik; Waldenström, Jonas; Salaneck, Erik

2014-01-15

Mosquitoes are the primary vectors of West Nile virus (WNV). Ticks have, however, been suggested to be potential reservoirs of WNV. In order to investigate their role in the spread of the virus, ticks, which had been collected from birds migrating northwards from Africa to Europe, were analyzed for the potential presence of WNV-RNA. On the Mediterranean islands Capri and Antikythira a total of 14,824 birds were captured and investigated from which 747 ticks were collected. Most of the identified ticks (93%) were nymphs and larvae of Hyalomma marginatum sensu lato, most of which were or appear to be Hyalomma rufipes. Of these ticks 729 were individually screened for WNV-RNA. None of the ticks was found to be WNV positive. Thus, there was no evidence that Hyalomma marginatum s.l. ticks play a role in the spread of WNV from Africa to Europe.

Drinking water boosts food intake rate, body mass increase and fat accumulation in migratory blackcaps (Sylvia atricapilla).

PubMed

Tsurim, Ido; Sapir, Nir; Belmaker, Jonathan; Shanni, Itai; Izhaki, Ido; Wojciechowski, Michał S; Karasov, William H; Pinshow, Berry

2008-05-01

Fat accumulation by blackcaps (Sylvia atricapilla) is a prerequisite for successful migratory flight in the autumn and has recently been determined to be constrained by availability of drinking water. Birds staging in a fruit-rich Pistacia atlantica plantation that had access to water increased their body mass and fat reserves both faster and to a greater extent than birds deprived of water. We conducted a series of laboratory experiments on birds captured during the autumn migration period in which we tested the hypotheses that drinking water increases food use by easing limitations on the birds' dietary choices and, consequently, feeding and food processing rates, and that the availability of drinking water leads to improved digestion and, therefore, to higher apparent metabolizable energy. Blackcaps were trapped in autumn in the Northern Negev Desert, Israel and transferred to individual cages in the laboratory. Birds were provided with P. atlantica fruit and mealworms, and had either free access to water (controls) or were water-deprived. In experiment 1, in which mealworm availability was restricted, water-deprived birds had a fourfold lower fruit and energy intake rates and, consequently, gained less fat and total mass than control birds. Water availability did not affect food metabolizability. In experiment 2, in which mealworms were provided ad libitum, water availability influenced the birds' diet: water-restricted birds ate more mealworms, while control birds consumed mainly P. atlantica fruit. Further, in experiment 2, fat and mass gain did not differ between the two treatment groups. We conclude that water availability may have important consequences for fat accumulation in migrating birds while they fatten at stopover sites, especially when water-rich food is scarce. Restricted water availability may also impede the blackcap's dietary shift from insectivory to frugivory, a shift probably necessary for successful pre-migratory fattening.

Effects of radio transmitters on migrating wood thrushes

USGS Publications Warehouse

Powell, L.A.; Krementz, D.G.; Lang, J.D.; Conroy, M.J.

1998-01-01

We quantified the effects of radio transmitters on Wood Thrushes (Hylocichla mustelina) using 4 yr of banding and telemetry data from Piedmont National Wildlife Refuge, Georgia. Flight performance models suggest that the 1.6-g transmitter shortens the migratory range of Wood Thrushes by only 60 km, and the estimated migratory range is adequate to accomplish migration even with limited fat stores. We used two strengths of line, 5- and 9-kg test-strength braided Dacron, to attach the transmitters using the thigh-harness method. We recaptured 13 returning radio-marked Wood Thrushes, seven of which were still marked. Six of the seven birds marked with the 5-kg test harnesses lost their transmitters within 1 yr while all six of the 9-kg test harnesses were still attached up to 21 mo later. Radio-marking did not reduce the return rates of adults and immatures, and the transmitters did not cause radio-marked birds to lose more mass than banded-only birds. Wood Thrushes can successfully carry a transmitter during migration with no detectable negative effects. We recommend continued use of the thigh-harness method, but we encourage the use of 5-kg cotton line.

Honey buzzards don't always make a beeline.

PubMed

Chapman, Jason W

2017-03-01

(a) European honey buzzards breeding in Western Europe primarily use soaring flight to make annual long-range migrations via the Strait of Gibraltar to winter in West Africa; this adult male was photographed on migration near Gibraltar. Photo: Javier Elloriaga. (b) Autumn migration routes of 12 satellite tagged adult European honey buzzards (colour-coded lines); compared with the shortest possible straight-line routes (dashed lines), most routes involved substantial westerly detours in Africa. Adapted from Vansteelant et al. (2016). (c) In contrast, Montagu's harriers predominantly use flapping flight during their migrations; this adult male is carrying a satellite transmitter. Photo: Theo van Kooten. (d) Autumn migration routes of 34 satellite tagged adult Montagu's harriers; migratory tracks more closely approached straight-line routes, and typically involved longer sea crossings, than seen in European honey buzzards. Adapted from Trierweiler et al. (). In Focus: Vansteelant, W.M.G., Shamoun-Baranes, J., van Manen, W., van Diermen, J. & Bouten, W. (2017) Seasonal detours by soaring migrants shaped by wind regimes along the East Atlantic Flyway. Journal of Animal Ecology, 86, 179-191. Migratory birds often make substantial detours from the shortest possible route during their annual migrations, which may potentially increase the duration and energetic cost of their journeys. Vansteelant et al. () investigate repeated migrations of adult European honey buzzards between the Netherlands and sub-Saharan Africa, and find that they make large westerly detours in Africa on both the spring and autumn routes. These detours allow migrants to capitalise on more favourable winds further along the route, thus reducing energy expenditure. Lifelong tracking studies will allow researchers to identify how migration routes have evolved to exploit predictable atmospheric and oceanic circulation patterns. © 2017 The Author. Journal of Animal Ecology © 2017 British Ecological Society.

The challenges of the first migration: movement and behaviour of juvenile vs. adult white storks with insights regarding juvenile mortality.

PubMed

Rotics, Shay; Kaatz, Michael; Resheff, Yehezkel S; Turjeman, Sondra Feldman; Zurell, Damaris; Sapir, Nir; Eggers, Ute; Flack, Andrea; Fiedler, Wolfgang; Jeltsch, Florian; Wikelski, Martin; Nathan, Ran

2016-07-01

Migration conveys an immense challenge, especially for juvenile birds coping with enduring and risky journeys shortly after fledging. Accordingly, juveniles exhibit considerably lower survival rates compared to adults, particularly during migration. Juvenile white storks (Ciconia ciconia), which are known to rely on adults during their first fall migration presumably for navigational purposes, also display much lower annual survival than adults. Using detailed GPS and body acceleration data, we examined the patterns and potential causes of age-related differences in fall migration properties of white storks by comparing first-year juveniles and adults. We compared juvenile and adult parameters of movement, behaviour and energy expenditure (estimated from overall dynamic body acceleration) and placed this in the context of the juveniles' lower survival rate. Juveniles used flapping flight vs. soaring flight 23% more than adults and were estimated to expend 14% more energy during flight. Juveniles did not compensate for their higher flight costs by increased refuelling or resting during migration. When juveniles and adults migrated together in the same flock, the juvenile flew mostly behind the adult and was left behind when they separated. Juveniles showed greater improvement in flight efficiency throughout migration compared to adults which appears crucial because juveniles exhibiting higher flight costs suffered increased mortality. Our findings demonstrate the conflict between the juveniles' inferior flight skills and their urge to keep up with mixed adult-juvenile flocks. We suggest that increased flight costs are an important proximate cause of juvenile mortality in white storks and likely in other soaring migrants and that natural selection is operating on juvenile variation in flight efficiency. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Genetic diversity of highly pathogenic H5N8 avian influenza viruses at a single overwintering site of migratory birds in Japan, 2014/15.

PubMed

Ozawa, M; Matsuu, A; Tokorozaki, K; Horie, M; Masatani, T; Nakagawa, H; Okuya, K; Kawabata, T; Toda, S

2015-05-21

We isolated eight highly pathogenic H5N8 avian influenza viruses (H5N8 HPAIVs) in the 2014/15 winter season at an overwintering site of migratory birds in Japan. Genetic analyses revealed that these isolates were divided into three groups, indicating the co-circulation of three genetic groups of H5N8 HPAIV among these migratory birds. These results also imply the possibility of global redistribution of the H5N8 HPAIVs via the migration of these birds next winter.

Stable Isotopes in Ecological Sceinces: Bird and Fish Diet and Migration in Virginia

NASA Astrophysics Data System (ADS)

Schmidt, S.; Dias, R. F.; Ake, R.; Jones, C. M.

2002-12-01

The preservation of ecologically sensitive habitats for birds and fishes in Virginia requires a detailed understanding of the important changes in diet and migration over the life span of the animal. Stable isotope analysis offers the potential to assess migration and trophic level variability in birds and fishes from southeastern Virginia and the greater Chesapeake Bay. Fish of various species and ages from different locations throughout the Chesapeake Bay were analyzed for carbon-13 and nitrogen-15 bulk natural abundance. Of particular note, blue fish were found to have significantly higher d15N values than striped bass which are believed to be trophic competitors. Observations are discussed relative to the maturity of the different fish, variation in water-mass chemistry (N-inputs), local environmental habitats, trophic relationships and migratory habits. In conjunction with banding studies being conducted by Virginia Department of Game and Inland Fisheries in the Great Dismal Swamp (VA), breast feathers from Carolina Wren, Common Yellowthroat, Northern Cardinal, Ovenbird, and Prothonotary Warbler were analyzed for carbon-13 and nitrogen-15 bulk natural abundance. Given the preliminary nature of this work our ability to identify trends between species was less than satisfying, thus highlighting the need for larger sample populations over more than one breeding season. However, within a given species (most notably the Prothonotary Warbler) we are able to discern a change in diet. The hatching year Prothonotary warbler were more enriched in both carbon-13 and nitrogen-15 than the after-hatching-year (AHY) birds, indicating a change in food sources between the two age groups. By sampling over time and at various sample sites, isotopic analyses allow a more detailed investigation of the spatial and temporal variation in the diets and migratory habits of fishes and birds in Virginia and the Chesapeake Bay.

Testing an attachment method for solar-powered tracking devices on a long-distance migrating shorebird

USGS Publications Warehouse

Chan, Ying-Chi; Brugge, Martin; Tibbitts, T. Lee; Dekinga, Anne; Porter, Ron; Klaassen, Raymond H. G.; Piersma, Theunis

2016-01-01

Small solar-powered satellite transmitters and GPS data loggers enable continuous, multi-year, and global tracking of birds. What is lacking, however, are reliable methods to attach these tracking devices to small migratory birds so that (1) flight performance is not impacted and (2) tags are retained during periods of substantial mass change associated with long-distance migration. We developed a full-body harness to attach tags to Red Knots (Calidris canutus), a medium-sized shorebird (average mass 124 g) that undertakes long-distance migrations. First, we deployed dummy tags on captive birds and monitored them over a complete migratory fattening cycle (February–July 2013) during which time they gained and lost 31–110 g and underwent a pre-alternate moult of body feathers. Using each individual’s previous year fattening and moult data in captivity as controls, we compared individual mass and moult differences between years between the tagged and reference groups, and concluded that the attachment did not impact mass and moult cycles. However, some birds shed feathers under the tags and under the polyester harness line commonly used in avian harnesses. Feather shedding was alleviated by switching to smoothed-bottom tags and monofilament harness lines. To field-trial this design, we deployed 5-g satellite transmitters on ten Red Knots released on 3 October 2013 in the Dutch Wadden Sea. Bird movements and tag performance appeared normal. However, nine tags stopped transmitting 11–170 days post-release which was earlier than expected. We attribute this to bird mortality rather than failure of the attachments or transmitters and suggest that the extra weight and drag caused by the tag and its feather-blocking shield increased the chance of depredation by the locally common Peregrine Falcons (Falco peregrinus). Our results demonstrate that species- and place-specific contexts can strongly determine tagging success. While captive trials are an important first step in developing an attachment method, field trials are essential to fully assess attachment designs.

Trans-equatorial migration routes, staging sites and wintering areas of a high-Arctic avian predator: the long-tailed Skua (Stercorarius longicaudus).

PubMed

Gilg, Olivier; Moe, Børge; Hanssen, Sveinn Are; Schmidt, Niels Martin; Sittler, Benoît; Hansen, Jannik; Reneerkens, Jeroen; Sabard, Brigitte; Chastel, Olivier; Moreau, Jérôme; Phillips, Richard A; Oudman, Thomas; Biersma, Elisabeth M; Fenstad, Anette A; Lang, Johannes; Bollache, Loïc

2013-01-01

The Long-tailed Skua, a small (<300 g) Arctic-breeding predator and seabird, is a functionally very important component of the Arctic vertebrate communities in summer, but little is known about its migration and winter distribution. We used light-level geolocators to track the annual movements of eight adult birds breeding in north-east Greenland (n = 3) and Svalbard (n = 5). All birds wintered in the Southern Hemisphere (mean arrival-departure dates on wintering grounds: 24 October-21 March): five along the south-west coast of Africa (0-40°S, 0-15°E), in the productive Benguela upwelling, and three further south (30-40°S, 0-50°E), in an area extending into the south-west Indian Ocean. Different migratory routes and rates of travel were documented during post-breeding (345 km d(-1) in late August-early September) and spring migrations (235 km d(-1) in late April) when most birds used a more westerly flyway. Among the different staging areas, a large region off the Grand Banks of Newfoundland appears to be the most important. It was used in autumn by all but one of the tracked birds (from a few days to three weeks) and in spring by five out of eight birds (from one to more than six weeks). Two other staging sites, off the Iberian coast and near the Azores, were used by two birds in spring for five to six weeks. Over one year, individuals travelled between 43,900 and 54,200 km (36,600-45,700 when excluding staging periods) and went as far as 10,500-13,700 km (mean 12,800 km) from their breeding sites. This study has revealed important marine areas in both the south and north Atlantic Ocean. Sustainable management of these ocean basins will benefit Long-tailed Skuas as well as other trans-equatorial migrants from the Arctic.

Fuel use and metabolic response to endurance exercise: a wind tunnel study of a long-distance migrant shorebird.

PubMed

Jenni-Eiermann, Susanne; Jenni, Lukas; Kvist, Anders; Lindström, Ake; Piersma, Theunis; Visser, G Henk

2002-08-01

This study examines fuel use and metabolism in a group of long-distance migrating birds, red knots Calidris canutus (Scolopacidae), flying under controlled conditions in a wind tunnel for up to 10 h. Data are compared with values for resting birds fasting for the same time. Plasma levels of free fatty acids, glycerol and uric acid were elevated during flight, irrespective of flight duration (1-10 h). Triglyceride levels, the estimated concentration of very-low-density lipoproteins (VLDLs) and beta-hydroxybutyrate levels were lower during flight, while glucose levels did not change. In flying birds, plasma levels of uric acid and lipid catabolites were positively correlated with the residual variation in body mass loss, and lipid catabolites with energy expenditure (as measured using the doubly labelled water method), after removing the effect of initial body mass. The plasma metabolite levels indicate: (i) that the rates of catabolism of lipids from adipose tissue and of protein are higher during flight; (ii) that low ketone body concentrations probably facilitate fatty acid release from adipose tissue; (iii) that low triglyceride and VLDL levels do not indicate the use of an additional pathway of fatty acid delivery, as found in small birds; and (iv) that the relationships between energy expenditure, body mass loss and metabolic pattern suggest that a higher individual energy expenditure entails a higher rate of catabolism of both lipids and protein and not a shift in fuel substrate.

Migrating birds’ use of stopover habitat in the southwestern United States

USGS Publications Warehouse

Ruth, Janet M.; Diehl, R.H.; Felix, R.K.

2012-01-01

In the arid Southwest, migratory birds are known to use riparian stopover habitats; we know less about how migrants use other habitat types during migratory stopover. Using radar data and satellite land-cover data, we determined the habitats with which birds are associated during migration stopover. Bird densities differed significantly by habitat type at all sites in at least one season. In parts of Arizona and New Mexico upland forest supported high densities of migrants, especially in fall. Developed habitat, in areas with little upland forest, also supported high densities of migrants. Scrub/shrub and grassland habitats supported low to intermediate densities, but because these habitat types dominate the Southwestern landscape, they may provide stopover habitat for larger numbers of migratory birds than previously recognized. These results are complicated by continuing challenges related to target identity (i.e., distinguishing among birds, arthropods and bats). Our results suggest that it is too simplistic to (1) consider the arid West as a largely inhospitable landscape in which there are only relatively small oases of habitat that provide the resources needed by all migrants, (2) think of western riparian and upland forests as supporting the majority of migrants in all cases, and (3) consider a particular habitat unimportant for stopover solely on the basis of low densities of migrants.

Wild bird migration across the Qinghai-Tibetan Plateau: A transmission route for highly pathogenic H5N1

USGS Publications Warehouse

Prosser, Diann J.; Cui, Peng; Takekawa, John Y.; Tang, Mingjie; Hou, Yuansheng; Collins, Bridget M.; Yan, Baoping; Hill, Nichola J.; Li, Tianxian; Li, Yongdong; Lei, Fumin; Guo, Shan; Xing, Zhi; He, Yubang; Zhou, Yuanchun; Douglas, David C.; Perry, William M.; Newman, Scott H.

2011-01-01

This is the first study to compare phylogenetics of the virus with spatial ecology of its host, and the combined results suggest that wild birds play a role in the spread of H5N1 in this region. However, the strength of the evidence would be improved with additional sequences from both poultry and wild birds on the Qinghai-Tibet Plateau where H5N1 has a clear stronghold.

Spring migration routes and chronology of surf scoters (Melanitta perspicillata): a synthesis of Pacific coast studies

USGS Publications Warehouse

de la Cruz, S.E.W.; Takekawa, John Y.; Wilson, M.T.; Nysewander, D.R.; Evenson, J.R.; Esler, Daniel N.; Boyd, W.S.; Ward, D.H.

2009-01-01

Understanding interconnectivity among wintering, stopover, and breeding areas of migratory birds is pivotal to discerning how events occurring in each might have a cross-seasonal effect on another. Such information can guide the location and timing of conservation efforts. Thus, we examined spring migration routes, chronology, and stopover use of 85 surf scoters (Melanitta perspicillata (L., 1758)) marked with satellite transmitters at four Pacific Flyway wintering sites: San Quintin Bay, Baja California; San Francisco Bay, California; Puget Sound, Washington; and Strait of Georgia, British Columbia. Eighty-three percent of marked scoters followed two main routes to the breeding area: a Southern Inland route involving staging in Puget Sound and Strait of Georgia and protracted inland migration, or a Northern Coastal route characterized by short movements along the Pacific coast of British Columbia and southeast Alaska with inland migration initiating from Lynn Canal and surrounding areas. Route choice was related to nesting site latitude in the Canadian Northern Boreal Forest. Data from birds tracked over 2 years indicated strong migration route fidelity, but altered chronology and stopover locations between years. Departure date varied by wintering site, but arrival and apparent settling dates were synchronous, suggesting individuals adjusted migration timing to meet an optimized reproductive schedule.

Comparative osteohistology of Hesperornis with reference to pygoscelid penguins: the effects of climate and behaviour on avian bone microstructure

PubMed Central

Wilson, Laura E.; Chin, Karen

2014-01-01

The broad biogeographic distribution of Hesperornis fossils in Late Cretaceous Western Interior Seaway deposits has prompted questions about whether they endured polar winters or migrated between mid- and high latitudes. Here, we compare microstructures of hesperornithiform long bones from Kansas and the Arctic to investigate whether migration or Late Cretaceous polar climate affected bone growth. We also examine modern penguin bones to determine how migration and climate may influence bone growth in birds with known behaviours. Histological analysis of hesperornithiform samples reveals continuous bone deposition throughout the cortex, plus an outer circumferential layer in adults. No cyclic growth marks, zonation or differences in vasculature are apparent in the Hesperornis specimens. Comparatively, migratory Adélie and chinstrap penguin bones show no zonation or changes in microstructure, suggesting that migration is not necessarily recorded in avian bone microstructure. Non-migratory gentoos show evidence of rapid bone growth possibly associated with increased chick growth rates in high-latitude populations and large body size. The absence of histological evidence for migration in extinct Hesperornis and extant pygoscelid penguins may reflect that these birds reached skeletal maturity before migration or overwintering. This underscores the challenges of using bone microstructure to infer the effects of behaviour and climate on avian growth. PMID:26064560

Year-round movements of a Wahlberg's eagle Aquila wahlbergi tracked by satellite

USGS Publications Warehouse

Meyburg, B.-U.; Mendelsohn, J.M.; Ellis, D.H.; Smith, D.G.; Meyburg, C.; Kemp, A.C.

1995-01-01

An adult female Wahlberg's Eagle from northern Namibia was tracked by satellite ovcr a total distance of 8816 km and located 104 times between 11 February and 4 November 1994. It migrated on an almost due north heading to northern Cameroon, north-eastern Nigeria and western Chad through the rain forest belt of the Congo and Zaire after the breeding season. The total trans-equatorial distance between the breeding and non-breeding ranges was 3520 km. During the non-breeding season the bird ranged over a large area (ca. 60 000 km2) for about six weeks (29 April - 14 June) in these three countries in a rather nomadic pattern covering a minimum distance of 1256 km. During two further months (14 June - 14 August) it restricted its movements to an area of about 50002 km near Maiduguri in the Sudan savannah of north-eastern Nigeria. The return migration took about two weeks longer than that to the north, which took about a month.

Estimating shorebird populations during spring stopover in rice fields of the Louisiana and Texas Gulf Coastal Plain

USGS Publications Warehouse

Norling, Wayne; Jeske, Clinton W.; Thigpen, Tyler F.; Chadwick, Paul C.

2012-01-01

Migrating shorebird populations using approximately 2% of Louisiana and Texas Gulf Coastal rice fields were surveyed during spring migration (March–May of 1997 and 1998) using biweekly stratified random surveys conducted at 50 roadside survey points and approximately 30,000 shorebirds were observed. Shorebird counts were extrapolated and almost 1.4 million birds in 1997 and over 1.6 million birds of 31 species in 1998 were estimated to use rice field habitat for stopover sites in Louisiana and Texas. Greater than 50% of the estimated North American populations were estimated to use rice field habitats for five species, including a species of concern, Buff-breasted Sandpiper (Tryngites subruficollis) at 187%. Because of predictability of suitable rice field habitat acreage, timing of field preparation and water availability, coastal rice prairies are identified as critical spring migration stopover sites.

Phenological synchrony of bird migration with tree flowering at desert riparian stopover sites

USGS Publications Warehouse

Kellermann, Jherime L.; van Riper, Charles

2015-01-01

Small-bodied songbirds replenish fat reserves during migration at stopover sites where they continually encounter novel and often unpredictable environmental conditions. The ability to select and utilize high quality habitats is critical to survival and fitness. Vegetation phenology is closely linked with emergence of insect prey and may provide valid cues of food availability for stopover habitat selection. Climate change is disrupting phenological synchrony across trophic levels with negative impacts on bird populations. However, whether synchrony or mismatch indicates historic or disrupted systems remains unclear. Many Neotropical migratory songbirds of western North America must cross arid regions where drought conditions related to climate change and human water use are expected to increase. We studied migrant abundance and the diversity (niche breadth) and proportional use of vegetation species as foraging substrates and their synchrony with vegetation flowering during spring migration along the lower Colorado River in the Sonoran Desert of the U.S. and Mexico.

Ecology of influenza A and Newcastle disease viruses in wild birds and poultry in Eastern Siberia (2012-2014)

USDA-ARS?s Scientific Manuscript database

The Russian Territory covering a large part of Northern Eurasia is of special interest for influenza virus ecology and evolution, for it is situated in the center of Eurasia and covers three major migration routes, combining bird populations from Asia, Africa, and Europe. During surveillance for av...

Are populations of neotropical migrant birds limited in summer or winter? implications for management

Treesearch

Thomas W. Sherry; Richard T. Holmes

1993-01-01

Understanding where in their annual cycle Neotropical-Nearctic migrant bird populations are limited is essential for developing effective management and conservation policies. A review of currently available information indicates that these long-distance migrant species may be limited by events and circumstances in both summer and winter, and possibly on migration as...

The Difference That Data Make: Examining Bird Migration Data to Build Scientific Skills

ERIC Educational Resources Information Center

Sturner, Kelly; Lucci, Karen

2015-01-01

This inquiry-based activity for high school students introduces concepts of ecology and the importance of data analysis to science. Using an investigative case, students generate independent questions about birds, access Cornell Lab of Ornithology online resources to collect data, organize and graph data using Excel, and make claims based on…

Arthropod abundance and seasonal bird use of bottomland forest harvest gaps

Treesearch

Christopher E. Moorman; Liessa T. Woen; John C. Kilgo; James L. Hanula; Scott Horn; Michael D. Ulyshen

2012-01-01

We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and...

Condition varies with habitat choice in postbreeding forest birds

Treesearch

Scott H. Stoleson

2013-01-01

Many birds that are experiencing population declines require extensive tracts of mature forest habitat for breeding. Recent work suggests that at least some may shift their habitat use to early-successional areas after nesting but before migration. I used constant-effort mist netting in regenerating clearcuts (4-8 years postcut) and dense mature-forest understories to...

Burning for birds: concepts and applications

Treesearch

R. Todd Engstrom; David J. Brownlie

2002-01-01

Prescribed fire is being used extensively for habitat management of non-game birds, although the area burned today is small relative to the amount of land that burned historically. Results of a non-scientific questionnaire of public and private land managers in the eastern U.S. revealed prescribed fire is being used to provide winter, breeding season, and migration...

Detours in long-distance migration across the Qinghai-Tibetan Plateau: individual consistency and habitat associations.

PubMed

Liu, Dongping; Zhang, Guogang; Jiang, Hongxing; Lu, Jun

2018-01-01

Migratory birds often follow detours when confronted with ecological barriers, and understanding the extent and the underlying drivers of such detours can provide important insights into the associated cost to the annual energy budget and the migration strategies. The Qinghai-Tibetan Plateau is the most daunting geographical barrier for migratory birds because the partial pressure of oxygen is dramatically reduced and flight costs greatly increase. We analyzed the repeated migration detours and habitat associations of four Pallas's Gulls Larus ichthyaetus across the Qinghai-Tibetan Plateau over 22 migration seasons. Gulls exhibited notable detours, with the maximum distance being more than double that of the expected shortest route, that extended rather than reduced the passage across the plateau. The extent of longitudinal detours significantly increased with latitude, and detours were longer in autumn than in spring. Compared with the expected shortest routes, proximity to water bodies increased along autumn migration routes, but detour-habitat associations were weak along spring migration routes. Thus, habitat availability was likely one, but not the only, factor shaping the extent of detours, and migration routes were determined by different mechanisms between seasons. Significant between-individual variation but high individual consistency in migration timing and routes were revealed in both seasons, indicating a stronger influence of endogenous schedules than local environmental conditions. Gulls may benefit from repeated use of familiar routes and stopover sites, which may be particularly significant in the challenging environment of the Qinghai-Tibetan Plateau.

It Takes Time to Be Cool: On the Relationship between Hyperthermia and Body Cooling in a Migrating Seaduck

PubMed Central

Guillemette, Magella; Polymeropoulos, Elias T.; Portugal, Steven J.; Pelletier, David

2017-01-01

The large amount of energy expended during flapping flight is associated with heat generated through the increased work of the flight muscles. This increased muscle work rate can manifest itself in core body temperature (Tb) increase of 1–2°C in birds during flight. Therefore, episodic body cooling may be mandatory in migratory birds. To elucidate the thermoregulatory strategy of a short-distance migrant, common eiders (Somateria mollissima), we implanted data loggers in the body cavity of wild birds for 1 year, and report information on Tb during their entire migration for 19 individuals. We show that the mean body temperature during flight (TbMean) in the eiders was associated with rises in Tb ranging from 0.2 to 1.5°C, largely depending on flight duration. To understand how eiders are dealing with hyperthermia during migration, we first compare, at a daily scale, how Tb differs during migration using a before-after approach. Only a slight difference was found (0.05°C) between the after (40.30°C), the before (40.41°C) and the migration (40.36°C) periods, indicating that hyperthermia during flight had minimal impact at this time scale. Analyses at the scale of a flight cycle (flight plus stops on the water), however, clearly shows that eiders were closely regulating Tb during migration, as the relationship between the storage of heat during flight was highly correlated (slope = 1) with the level of heat dumping during stops, at both inter-individual and intra-individual levels. Because Tb at the start of a flight (TbStart) was significantly and positively related to Tb at the end of a flight (TbEnd), and the maximal attained Tb during a flight (TbMax), we conclude that in absence of sufficient body cooling during stopovers, eiders are likely to become increasingly hyperthermic during migration. Finally, we quantified the time spent cooling down during migration to be 36% of their daily (24 h) time budget, and conclude that behavioral body cooling in relation to hyperthermia represents an important time cost. PMID:28790930

Unidirectional pulmonary airflow patterns in the savannah monitor lizard.

PubMed

Schachner, Emma R; Cieri, Robert L; Butler, James P; Farmer, C G

2014-02-20

The unidirectional airflow patterns in the lungs of birds have long been considered a unique and specialized trait associated with the oxygen demands of flying, their endothermic metabolism and unusual pulmonary architecture. However, the discovery of similar flow patterns in the lungs of crocodilians indicates that this character is probably ancestral for all archosaurs--the group that includes extant birds and crocodilians as well as their extinct relatives, such as pterosaurs and dinosaurs. Unidirectional flow in birds results from aerodynamic valves, rather than from sphincters or other physical mechanisms, and similar aerodynamic valves seem to be present in crocodilians. The anatomical and developmental similarities in the primary and secondary bronchi of birds and crocodilians suggest that these structures and airflow patterns may be homologous. The origin of this pattern is at least as old as the split between crocodilians and birds, which occurred in the Triassic period. Alternatively, this pattern of flow may be even older; this hypothesis can be tested by investigating patterns of airflow in members of the outgroup to birds and crocodilians, the Lepidosauromorpha (tuatara, lizards and snakes). Here we demonstrate region-specific unidirectional airflow in the lungs of the savannah monitor lizard (Varanus exanthematicus). The presence of unidirectional flow in the lungs of V. exanthematicus thus gives rise to two possible evolutionary scenarios: either unidirectional airflow evolved independently in archosaurs and monitor lizards, or these flow patterns are homologous in archosaurs and V. exanthematicus, having evolved only once in ancestral diapsids (the clade encompassing snakes, lizards, crocodilians and birds). If unidirectional airflow is plesiomorphic for Diapsida, this respiratory character can be reconstructed for extinct diapsids, and evolved in a small ectothermic tetrapod during the Palaeozoic era at least a hundred million years before the origin of birds.

A global analysis of bird plumage patterns reveals no association between habitat and camouflage

PubMed Central

Marshall, Kate L.A.; Gluckman, Thanh-Lan

2016-01-01

Evidence suggests that animal patterns (motifs) function in camouflage. Irregular mottled patterns can facilitate concealment when stationary in cluttered habitats, whereas regular patterns typically prevent capture during movement in open habitats. Bird plumage patterns have predominantly converged on just four types—mottled (irregular), scales, bars and spots (regular)—and habitat could be driving convergent evolution in avian patterning. Based on sensory ecology, we therefore predict that irregular patterns would be associated with visually noisy closed habitats and that regular patterns would be associated with open habitats. Regular patterns have also been shown to function in communication for sexually competing males to stand-out and attract females, so we predict that male breeding plumage patterns evolved in both open and closed habitats. Here, taking phylogenetic relatedness into account, we investigate ecological selection for bird plumage patterns across the class Aves. We surveyed plumage patterns in 80% of all avian species worldwide. Of these, 2,756 bird species have regular and irregular plumage patterns as well as habitat information. In this subset, we tested whether adult breeding/non-breeding plumages in each sex, and juvenile plumages, were associated with the habitat types found within the species’ geographical distributions. We found no evidence for an association between habitat and plumage patterns across the world’s birds and little phylogenetic signal. We also found that species with regular and irregular plumage patterns were distributed randomly across the world’s eco-regions without being affected by habitat type. These results indicate that at the global spatial and taxonomic scale, habitat does not predict convergent evolution in bird plumage patterns, contrary to the camouflage hypothesis. PMID:27867762

A global analysis of bird plumage patterns reveals no association between habitat and camouflage.

PubMed

Somveille, Marius; Marshall, Kate L A; Gluckman, Thanh-Lan

2016-01-01

Evidence suggests that animal patterns (motifs) function in camouflage. Irregular mottled patterns can facilitate concealment when stationary in cluttered habitats, whereas regular patterns typically prevent capture during movement in open habitats. Bird plumage patterns have predominantly converged on just four types-mottled (irregular), scales, bars and spots (regular)-and habitat could be driving convergent evolution in avian patterning. Based on sensory ecology, we therefore predict that irregular patterns would be associated with visually noisy closed habitats and that regular patterns would be associated with open habitats. Regular patterns have also been shown to function in communication for sexually competing males to stand-out and attract females, so we predict that male breeding plumage patterns evolved in both open and closed habitats. Here, taking phylogenetic relatedness into account, we investigate ecological selection for bird plumage patterns across the class Aves. We surveyed plumage patterns in 80% of all avian species worldwide. Of these, 2,756 bird species have regular and irregular plumage patterns as well as habitat information. In this subset, we tested whether adult breeding/non-breeding plumages in each sex, and juvenile plumages, were associated with the habitat types found within the species' geographical distributions. We found no evidence for an association between habitat and plumage patterns across the world's birds and little phylogenetic signal. We also found that species with regular and irregular plumage patterns were distributed randomly across the world's eco-regions without being affected by habitat type. These results indicate that at the global spatial and taxonomic scale, habitat does not predict convergent evolution in bird plumage patterns, contrary to the camouflage hypothesis.

Moonlight Drives Ocean-Scale Mass Vertical Migration of Zooplankton during the Arctic Winter.

PubMed

Last, Kim S; Hobbs, Laura; Berge, Jørgen; Brierley, Andrew S; Cottier, Finlo

2016-01-25

In extreme high-latitude marine environments that are without solar illumination in winter, light-mediated patterns of biological migration have historically been considered non-existent [1]. However, diel vertical migration (DVM) of zooplankton has been shown to occur even during the darkest part of the polar night, when illumination levels are exceptionally low [2, 3]. This paradox is, as yet, unexplained. Here, we present evidence of an unexpected uniform behavior across the entire Arctic, in fjord, shelf, slope and open sea, where vertical migrations of zooplankton are driven by lunar illumination. A shift from solar-day (24-hr period) to lunar-day (24.8-hr period) vertical migration takes place in winter when the moon rises above the horizon. Further, mass sinking of zooplankton from the surface waters and accumulation at a depth of ∼50 m occurs every 29.5 days in winter, coincident with the periods of full moon. Moonlight may enable predation of zooplankton by carnivorous zooplankters, fish, and birds now known to feed during the polar night [4]. Although primary production is almost nil at this time, lunar vertical migration (LVM) may facilitate monthly pulses of carbon remineralization, as they occur continuously in illuminated mesopelagic systems [5], due to community respiration of carnivorous and detritivorous zooplankton. The extent of LVM during the winter suggests that the behavior is highly conserved and adaptive and therefore needs to be considered as "baseline" zooplankton activity in a changing Arctic ocean [6-9]. VIDEO ABSTRACT. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Evaluating predictors of local dabbling duck abundance during migration: Managing the spectrum of conditions faced by migrants

USGS Publications Warehouse

Aagaard, Kevin; Crimmins, Shawn M.; Thogmartin, Wayne E.; Tavernia, Brian G.; Lyons, James E.

2015-01-01

The development of robust modelling techniques to derive inferences from large-scale migratory bird monitoring data at appropriate scales has direct relevance to their management. The Integrated Waterbird Management and Monitoring programme (IWMM) represents one of the few attempts to monitor migrating waterbirds across entire flyways using targeted local surveys. This dataset included 13,208,785 waterfowl (eight Anas species) counted during 28,000 surveys at nearly 1,000 locations across the eastern United States between autumn 2010 and spring 2013 and was used to evaluate potential predictors of waterfowl abundance at the wetland scale. Mixed-effects, log-linear models of local abundance were built for the Atlantic and Mississippi flyways during spring and autumn migration to identify factors relating to habitat structure, forage availability, and migration timing that influence target dabbling duck species abundance. Results indicated that migrating dabbling ducks responded differently to environmental factors. While the factors identified demonstrated a high degree of importance, they were inconsistent across species, flyways and seasons. Furthermore, the direction and magnitude of the importance of each covariate group considered here varied across species. Given our results, actionable policy recommendations are likely to be most effective if they consider species-level variation within targeted taxonomic units and across management areas. The methods implemented here can easily be applied to other contexts, and serve as a novel investigation into local-level population patterns using data from broad-scale monitoring programmes.

Candidate genes have sex-specific effects on timing of spring migration and moult speed in a long-distance migratory bird.

PubMed

Bazzi, Gaia; Podofillini, Stefano; Gatti, Emanuele; Gianfranceschi, Luca; Cecere, Jacopo G; Spina, Fernando; Saino, Nicola; Rubolini, Diego

2017-10-01

The timing of major life-history events, such as migration and moult, is set by endogenous circadian and circannual clocks, that have been well characterized at the molecular level. Conversely, the genetic sources of variation in phenology and in other behavioral traits have been sparsely addressed. It has been proposed that inter-individual variability in the timing of seasonal events may arise from allelic polymorphism at phenological candidate genes involved in the signaling cascade of the endogenous clocks. In this study of a long-distance migratory passerine bird, the willow warbler Phylloscopus trochilus , we investigated whether allelic variation at 5 polymorphic loci of 4 candidate genes ( Adcyap1 , Clock , Creb1 , and Npas2 ), predicted 2 major components of the annual schedule, namely timing of spring migration across the central Mediterranean sea and moult speed, the latter gauged from ptilochronological analyses of tail feathers moulted in the African winter quarters. We identified a novel Clock gene locus ( Clock region 3) showing polyQ polymorphism, which was however not significantly associated with any phenotypic trait. Npas2 allele size predicted male (but not female) spring migration date, with males bearing longer alleles migrating significantly earlier than those bearing shorter alleles. Creb1 allele size significantly predicted male (but not female) moult speed, longer alleles being associated with faster moult. All other genotype-phenotype associations were statistically non-significant. These findings provide new evidence for a role of candidate genes in modulating the phenology of different circannual activities in long-distance migratory birds, and for the occurrence of sex-specific candidate gene effects.

Satellite tracking of two Lesser Spotted Eagles, Aquila pomarina, migrating from Namibia

USGS Publications Warehouse

Meyburg, B.-U.; Ellis, D.H.; Meyburg, C.; Mendelsohn, J.M.; Scheller, W.

2001-01-01

One immature and one subadult Lesser Spotted Eagle, Aquila pomarina, were followed by satellite telemetry from their nonbreeding areas in Namibia. Both birds were fitted with transmitters (PTTs) in February 1994 and tracked, the immature for six months and three weeks, the subadult for eight months and two weeks, over distances of 10 084 and 16 773 km, respectively. During their time in Namibia both birds' movements were in response to good local rainfall. The immature eagle left Namibia at the end of February, the subadult at the end of March. They flew to their respective summer quarters in Hungary and the Ukraine, arriving there 2.5 and 1.5 months later than the breeding adults. The immature eagle took over two months longer on the homeward journey than a breeding male followed by telemetry in a previous study. On returning, the immature eagle followed the narrow flightpath through Africa used by other Lesser Spotted Eagles on their outward migration. It reached this corridor, which runs roughly between longitudes 31?? and 36?? East from Suez to Lake Tanganyika, veering from the shortest route in a direction east-northeast through Angola and Zambia to the southern end of Lake Tanganyika. The route taken by the subadult bird on its return migration differed markedly from that of all Lesser Spotted Eagles tracked to date, running further west through the Democratic Republic of Congo where, level with the equator, it flew over the eastern rainforest of that country. The outward migration, however, followed the same corridor and coincided in time with the migration of adults. [A German translation of the abstract is provided on p. 40.].

Evidence that dorsally mounted satellite transmitters affect migration chronology of Northern Pintails

USGS Publications Warehouse

Hupp, Jerry W.; Kharitonov, Sergei; Yamaguchi, Noriyuki M.; Ozaki, K.; Flint, Paul L.; Pearce, John M.; Tokita, Ken-ichi; Shimada, Tetsuo; Higuchi, Hiroyoshi

2015-01-01

We compared migration movements and chronology between Northern Pintails (Anas acuta) marked with dorsally mounted satellite transmitters and pintails marked only with tarsus rings. During weekly intervals of spring and autumn migration between their wintering area in Japan and nesting areas in Russia, the mean distance that ringed pintails had migrated was up to 1000 km farther than the mean distance radiomarked pintails migrated. Radiomarked pintails were detected at spring migration sites on average 9.9 days (90 % CI 8.0, 11.8) later than ringed pintails that were recovered within 50 km. Although ringed and radiomarked pintails departed from Japan on similar dates, the disparity in detection of radiomarked versus ringed pintails at shared sites increased 7.7 days (90 % CI 5.2, 10.2) for each 1000 km increase in distance from Japan. Thus, pintails marked with satellite transmitters arrived at nesting areas that were 2500 km from Japan on average 19 days later than ringed birds. Radiomarked pintails were detected at autumn migration stopovers on average 13.1 days (90 % CI 9.8, 16.4) later than ringed birds that were recovered within 50 km. We hypothesize that dorsal attachment of 12–20 g satellite transmitters to Northern Pintails increased the energetic cost of flight, which resulted in more rapid depletion of energetic reserves and shortened the distance pintails could fly without refueling. Radiomarked pintails may have used more stopovers or spent longer periods at stopovers. causing their migration schedule to diverge from ringed pintails. We urge further evaluation of the effects of dorsally mounted transmitters on migration chronology of waterfowl.

Avian influenza survey in migrating waterfowl in Sonora, Mexico.

PubMed

Montalvo-Corral, M; López-Robles, G; Hernández, J

2011-02-01

A two-year survey was carried out on the occurrence of avian influenza in migrating birds in two estuaries of the Mexican state of Sonora, which is located within the Pacific flyway. Cloacal and oropharyngeal swabs were collected from 1262 birds, including 20 aquatic bird species from the Moroncarit and Tobari estuaries in Sonora, Mexico. Samples were tested for type A influenza (M), H5 Eurasian and North American subtypes (H5EA and H5NA respectively) and the H7 North American subtype (H7NA). Gene detection was determined by one-step real-time reverse transcription polymerase chain reaction (RRT-PCR). The results revealed that neither the highly pathogenic avian influenza virus H5 of Eurasian lineage nor H7NA were detected. The overall prevalence of avian influenza type A (M-positive) in the sampled birds was 3.6% with the vast majority in dabbling ducks (Anas species). Samples from two birds, one from a Redhead (Aythya americana) and another from a Northern Shoveler (Anas clypeata), were positive for the low-pathogenic H5 avian influenza virus of North American lineage. These findings represented documented evidence of the occurrence of avian influenza in wintering birds in the Mexican wetlands. This type of study contributes to the understanding of how viruses spread to new regions of North America and highlights the importance of surveillance for the early detection and control of potentially pathogenic strains, which could affect animal and human health. © 2010 Blackwell Verlag GmbH.

Are birds stressed during long-term flights? A wind-tunnel study on circulating corticosterone in the red knot.

PubMed

Jenni-Eiermann, Susanne; Hasselquist, Dennis; Lindström, Ake; Koolhaas, Anita; Piersma, Theunis

2009-01-01

During endurance flight most birds do not feed and have to rely on their body reserves. Fat and protein is catabolised to meet the high energetic demands. Even though the hormonal regulation of migration is complex and not yet fully understood, the adrenocortical hormone corticosterone crystallizes to play a major role in controlling physiological traits in migratory birds during flight. However, results from field studies are partially equivocal, not least because data from birds during endurance flight are hard to get and present mostly a momentary shot. A wind-tunnel experiment offered the possibility to measure repeatedly under controlled conditions the effect of long flights on the stress hormone corticosterone. In a long-distance migrating shorebird, the red knot Calidris canutus, we measured plasma concentrations of corticosterone within 3 min and after a restraint time of 30 min directly after 2h and 10h non-stop flights, respectively, and during rest. Baseline corticosterone levels were unchanged directly after the flights, indicating that endurance flight did not affect corticosterone levels. The adrenocortical response to restraint showed the typical rise in birds during rest, while birds after a 2 or 10h flight substantially decreased plasma corticosterone concentrations. We suggest that the negative adrenocortical response to restraint after flight is part of the mechanism to reduce the proteolytic effect of corticosterone to save muscle protein and to avoid muscle damaging effects.

Combining Breeding Bird Survey and distance sampling to estimate density of migrant and breeding birds

USGS Publications Warehouse

Somershoe, S.G.; Twedt, D.J.; Reid, B.

2006-01-01

We combined Breeding Bird Survey point count protocol and distance sampling to survey spring migrant and breeding birds in Vicksburg National Military Park on 33 days between March and June of 2003 and 2004. For 26 of 106 detected species, we used program DISTANCE to estimate detection probabilities and densities from 660 3-min point counts in which detections were recorded within four distance annuli. For most species, estimates of detection probability, and thereby density estimates, were improved through incorporation of the proportion of forest cover at point count locations as a covariate. Our results suggest Breeding Bird Surveys would benefit from the use of distance sampling and a quantitative characterization of habitat at point count locations. During spring migration, we estimated that the most common migrant species accounted for a population of 5000-9000 birds in Vicksburg National Military Park (636 ha). Species with average populations of 300 individuals during migration were: Blue-gray Gnatcatcher (Polioptila caerulea), Cedar Waxwing (Bombycilla cedrorum), White-eyed Vireo (Vireo griseus), Indigo Bunting (Passerina cyanea), and Ruby-crowned Kinglet (Regulus calendula). Of 56 species that bred in Vicksburg National Military Park, we estimated that the most common 18 species accounted for 8150 individuals. The six most abundant breeding species, Blue-gray Gnatcatcher, White-eyed Vireo, Summer Tanager (Piranga rubra), Northern Cardinal (Cardinalis cardinalis), Carolina Wren (Thryothorus ludovicianus), and Brown-headed Cowbird (Molothrus ater), accounted for 5800 individuals.

Campylobacter jejuni and Campylobacter coli in wild birds on Danish livestock farms.

PubMed

Hald, Birthe; Skov, Marianne Nielsine; Nielsen, Eva Møller; Rahbek, Carsten; Madsen, Jesper Johannes; Wainø, Michael; Chriél, Mariann; Nordentoft, Steen; Baggesen, Dorte Lau; Madsen, Mogens

2016-02-03

Reducing the occurrence of campylobacteriosis is a food safety issue of high priority, as in recent years it has been the most commonly reported zoonosis in the EU. Livestock farms are of particular interest, since cattle, swine and poultry are common reservoirs of Campylobacter spp. The farm environment provides attractive foraging and breeding habitats for some bird species reported to carry thermophilic Campylobacter spp. We investigated the Campylobacter spp. carriage rates in 52 wild bird species present on 12 Danish farms, sampled during a winter and a summer season, in order to study the factors influencing the prevalence in wild birds according to their ecological guild. In total, 1607 individual wild bird cloacal swab samples and 386 livestock manure samples were cultured for Campylobacter spp. according to the Nordic Committee on Food Analysis method NMKL 119. The highest Campylobacter spp. prevalence was seen in 110 out of 178 thrushes (61.8 %), of which the majority were Common Blackbird (Turdus merula), and in 131 out of 616 sparrows (21.3 %), a guild made up of House Sparrow (Passer domesticus) and Eurasian Tree Sparrow (Passer montanus). In general, birds feeding on a diet of animal or mixed animal and vegetable origin, foraging on the ground and vegetation in close proximity to livestock stables were more likely to carry Campylobacter spp. in both summer (P < 0.001) and winter (P < 0.001) than birds foraging further away from the farm or in the air. Age, fat score, gender, and migration range were not found to be associated with Campylobacter spp. carriage. A correlation was found between the prevalence (%) of C. jejuni in wild birds and the proportions (%) of C. jejuni in both manure on cattle farms (R(2) = 0.92) and poultry farms (R(2) = 0.54), and between the prevalence (%) of C. coli in wild birds and the proportions (%) of C. coli in manure on pig farms (R(2) = 0.62). The ecological guild of wild birds influences the prevalence of Campylobacter spp. through the behavioural patterns of the birds. More specifically, wild birds eating food of animal or mixed animal and vegetable origin and foraging on the ground close to livestock were more likely to carry Campylobacter spp. than those foraging further away or hunting in the air. These findings suggest that wild birds may play a role in sustaining the epidemiology of Campylobacter spp. on farms.

Normalized burn ratios link fire severity with patterns of avian occurrence

USGS Publications Warehouse

Rose, Eli T.; Simons, Theodore R.; Klein, Rob; McKerrow, Alexa

2016-01-01

ContextRemotely sensed differenced normalized burn ratios (DNBR) provide an index of fire severity across the footprint of a fire. We asked whether this index was useful for explaining patterns of bird occurrence within fire adapted xeric pine-oak forests of the southern Appalachian Mountains.ObjectivesWe evaluated the use of DNBR indices for linking ecosystem process with patterns of bird occurrence. We compared field-based and remotely sensed fire severity indices and used each to develop occupancy models for six bird species to identify patterns of bird occurrence following fire.MethodsWe identified and sampled 228 points within fires that recently burned within Great Smoky Mountains National Park. We performed avian point counts and field-assessed fire severity at each bird census point. We also used Landsat™ imagery acquired before and after each fire to quantify fire severity using DNBR. We used non-parametric methods to quantify agreement between fire severity indices, and evaluated single season occupancy models incorporating fire severity summarized at different spatial scales.ResultsAgreement between field-derived and remotely sensed measures of fire severity was influenced by vegetation type. Although occurrence models using field-derived indices of fire severity outperformed those using DNBR, summarizing DNBR at multiple spatial scales provided additional insights into patterns of occurrence associated with different sized patches of high severity fire.ConclusionsDNBR is useful for linking the effects of fire severity to patterns of bird occurrence, and informing how high severity fire shapes patterns of bird species occurrence on the landscape.

Interspecific Comparison of the Performance of Soaring Migrants in Relation to Morphology, Meteorological Conditions and Migration Strategies

PubMed Central

Mellone, Ugo; Klaassen, Raymond H. G.; García-Ripollés, Clara; Limiñana, Ruben; López-López, Pascual; Pavón, Diego; Strandberg, Roine; Urios, Vicente; Vardakis, Michalis; Alerstam, Thomas

2012-01-01

Background Performance of migrating birds can be affected by a number of intrinsic and extrinsic factors like morphology, meteorological conditions and migration strategies. We compared travel speeds of four raptor species during their crossing of the Sahara desert. Focusing the analyses on this region allows us to compare different species under equivalent conditions in order to disentangle which factors affect migratory performance. Methodology/Principal Finding We tracked raptors using GPS satellite transmitters from Sweden, Spain and Italy, and evaluated their migratory performance at both an hourly and a daily scale. Hourly data (flight speed and altitude for intervals of two hours) were analyzed in relation to time of day, species and season, and daily data (distance between roosting sites) in relation to species, season, day length and tailwind support. Conclusions/Significance Despite a clear variation in morphology, interspecific differences were generally very small, and did only arise in spring, with long-distance migrants (>5000 km: osprey and Western marsh-harrier) being faster than species that migrate shorter distances (Egyptian vulture and short-toed eagle). Our results suggest that the most important factor explaining hourly variation in flight speed is time of day, while at a daily scale, tailwind support is the most important factor explaining variation in daily distance, raising new questions about the consequences of possible future changes in worldwide wind patterns. PMID:22768314

Direct Visual and Radar Methods for the Detection, Quantification, and Prediction of Bird Migration.

DTIC Science & Technology

1980-04-30

domesticus), 12 cm2 ; and Rock Dove ( Columba livia ), 80 cm’. Eastwood (1967) has given the radar cross sections of a number of European birds as mea...in Table 4 and Table 5 it is apparent that a single pigeon ( Columba livia ) flying toward the radar should theoretically produce an echo on the ASR-4

Monitoring bird migration in the Caribbean basin: multi-national cooperation can close the loop

Treesearch

Paul B. Hamel; Cecilia M. Riley; W. C. Hunter; Mark S. Woodrey

2005-01-01

The Gulf Coast Bird Observatory (GCBO) and the Southeastern Working Group of Partners in Flight have developed a protocol to monitor landbirds with volunteer observers performing avian censuses in the field. Field observations are compiled within a powerful internet database, and recording and summary capability is maintained by the GCBO. More than 100 observers have...

Novel Reassortant Highly Pathogenic Avian Influenza (H5N8) Virus in Zoos, India.

PubMed

Nagarajan, Shanmugasundaram; Kumar, Manoj; Murugkar, Harshad V; Tripathi, Sushil; Shukla, Shweta; Agarwal, Sonam; Dubey, Garima; Nagi, Raunaq Singh; Singh, Vijendra Pal; Tosh, Chakradhar

2017-04-01

Highly pathogenic avian influenza (H5N8) viruses were detected in waterfowl at 2 zoos in India in October 2016. Both viruses were different 7:1 reassortants of H5N8 viruses isolated in May 2016 from wild birds in the Russian Federation and China, suggesting virus spread during southward winter migration of birds.

An overview of a landbird monitoring program at Tortuguero, on the Caribbean coast of Costa Rica

Treesearch

C. John Ralph; Margaret J. Widdowson; Robert I. Frey; Pablo A. Herrera; Brian P. O' Donnell

2005-01-01

Since 1994, the Tortuguero Integrated Bird Monitoring Program has been monitoring birds in a coastal lowland rain forest of northeast Costa Rica. The Program has combined the use of area searches, constanteffort mist netting, and migration counts into a longterm landbird monitoring and training program following the recommendations of the Partners In Flight &ndash...

Radar ornithology and the conservation of migratory birds

Treesearch

Sidney A. Gauthreaux; Carroll G. Belser

2005-01-01

It is possible to study with surveillance radar the movements of migrating birds in the atmosphere at different spatial scales. At a spatial scale within a range of 6 kilometers, high-resolution, 3-centimeter wavelength surveillance radar (e.g. BIRDRAD) can detect the departure of migrants from different types of habitat within a few kilometers of the radar. The radar...

Movements by juvenile and immature Steller's Sea Eagles Haliaeetus pelagicus tracked by satellite

USGS Publications Warehouse

McGrady, M.J.; Ueta, M.; Potapov, E.R.; Utekhina, I.; Marterov, V.; Ladyguine, A.; Zykov, V.; Cibor, J.; Fuller, Mark R.; Seegar, J.K.

2003-01-01

Twenty-four juvenile Steller's Sea Eagles Haliaeetus pelagicus were tracked via satellite from natal areas in Magadan, Kabarovsk, Amur, Sakhalin and Kamchatka. Nestling dispersal occurred between 9 September and 6 December (n = 24), mostly 14 September-21 October, and did not differ among regions or years. Most eagles made stopovers of 4-28 days during migration. Migration occurred 9 September-18 January, mostly along previously described routes, taking 4-116 days to complete (n = 18). Eagles averaged 47.8 km/day excluding stopovers; 22.9 km/day including stopovers. The mean degrees of latitude spanned during migration was: Kamchatka, 2.1; Magadan, 11.6; Amur, 7.3; and Sakhalin, 1.1. Eagle winter range sizes varied. Eagles concentrated in 1-3 subareas within overall winter ranges. The mean size of the first wintering subareas was 274 km2, the second 529 km2, and the third 1181 km2. Second wintering areas were south of first wintering areas. Spring migration started between 2 February and 31 March. Two eagles from Magadan were tracked onto summering grounds, well south of their natal areas. Both had early and late summering areas. One bird was followed for 25 months. It initiated its second autumn migration in the first half of October and arrived on its wintering grounds on 26 December. The second autumn migration covered 1839 km (20.9-22.4 km/day). Unlike its first winter when it used two subareas, this bird used only one subarea in 1998-99, but this was located near wintering areas used in 1997-98. It left its wintering ground between 13 April and 13 May, and arrived on its summering grounds between 7 June and 8 July. Unlike most satellite radiotracking studies, data are presented from a relatively large number of birds from across their breeding range, including new information on eagle movements on the wintering grounds and during the second year

Migration and winter distributions of canvasbacks staging on the Upper Mississippi River

USGS Publications Warehouse

Serie, J.R.; Trauger, D.L.; Sharp, D.E.

1983-01-01

Fall and winter distribution patterns of canvasbacks (Aythya valisineria) staging on the upper Mississippi River near LaCrosse, Wisconsin (navigational Pools 7 and 8) and Keokuk, Iowa (Pool 19) were studied during 1973-77. Sightings and recoveries obtained from 1,488 color-marked males during 1973-75 and 3,789 banded males and females during 1973-77 suggested 2 principal migration corridors: 1 extending eastward from Pools 7 and 8 to the eastern Great Lakes and southeast to the Mid-Atlantic Region and another southward from Pools 7 and 8 to the lower Mississippi Valley, Gulf Coast, and east Texas regions. These discrete populations stage concurrently on Pools 7 and 8 during the fall, but winter in different areas of the Atlantic, Mississippi, and Central flyways. Populations staging on Pool 19 were not discrete from those staging on Pools 7 and 8. A continual turnover of birds passing through these staging areas was indicated. Canvasbacks wintering in the Mississippi and Central flyways were widely dispersed among a variety of habitats, whereas canvasbacks wintering in the Atlantic Flyway were concentrated in a few traditional habitats. Canvasbacks exhibited strong fidelity to wintering areas. Distribution patterns and population attributes of canvasbacks during fall and winter may be explained by the predictability of natural foods and their ability to exploit these foods.

Migratory patterns and population structure among breeding and wintering red-breasted mergansers (Mergus serrator) and common mergansers (M. merganser)

USGS Publications Warehouse

Pearce, J.M.; McCracken, K.G.; Christensen, Thomas K.; Zhuravlev, Y.N.

2009-01-01

Philopatry has long been assumed to structure populations of waterfowl and other species of birds genetically, especially via maternally transmitted mitochondrial DNA (mtDNA), yet other migratory behaviors and nesting ecology (use of ground vs. cavity sites) may also contribute to population genetic structure. We investigated the effects of migration and nesting ecology on the population genetic structure of two Holarctic waterfowl, the Red-breasted Merganser (Mergus serrator) and Common Merganser (M. merganser), using mtDNA control-region sequence data. Red-breasted Mergansers (a ground-nesting species) exhibited lower levels of population differentiation across their North American range, possibly as a result of post-Pleistocene range expansion and population growth. By contrast, Common Mergansers (a cavity-nesting species) breeding in western and eastern North America were strongly differentiated, as were continental groups in North America and Europe. Our hypothesis that population differentiation of breeding female Common Mergansers results from limited migration during non-breeding periods was not supported, in that equally heterogeneous mtDNA lineages were observed in males and females on several wintering areas. The interspecific differences in mtDNA patterns for these two closely related species may have resulted from factors related to nesting ecology (ground vs. cavity nesting) and responses to historical climate change.

Swainson's Thrushes do not show strong wind selectivity prior to crossing the Gulf of Mexico.

PubMed

Bolus, Rachel T; Diehl, Robert H; Moore, Frank R; Deppe, Jill L; Ward, Michael P; Smolinsky, Jaclyn; Zenzal, Theodore J

2017-10-27

During long-distance fall migrations, nocturnally migrating Swainson's Thrushes often stop on the northern Gulf of Mexico coast before flying across the Gulf. To minimize energetic costs, trans-Gulf migrants should stop over when they encounter crosswinds or headwinds, and depart with supportive tailwinds. However, time constrained migrants should be less selective, balancing costs of headwinds with benefits of continuing their migrations. To test the hypotheses that birds select supportive winds and that selectivity is mediated by seasonal time constraints, we examined whether local winds affected Swainson's Thrushes' arrival and departure at Ft. Morgan, Alabama, USA at annual, seasonal, and nightly time scales. Additionally, migrants could benefit from forecasting future wind conditions, crossing on nights when winds are consistently supportive across the Gulf, thereby avoiding the potentially lethal consequences of depleting their energetic reserves over water. To test whether birds forecast, we developed a movement model, calculated to what extent departure winds were predictive of future Gulf winds, and tested whether birds responded to predictability. Swainson's Thrushes were only slightly selective and did not appear to forecast. By following the simple rule of avoiding only the strongest headwinds at departure, Swainson's Thrushes could survive the 1500 km flight between Alabama and Veracruz, Mexico.

Size dimorphism, molt status, and body mass variation of Prairie Falcons nesting in the Snake River Birds of Prey National Conservation Area

USGS Publications Warehouse

Steenhof, Karen; McKinley, James O.

2006-01-01

Birds face challenges in how they allocate energy during the reproductive season. Most temperate zone species do not breed and molt at the same time, presumably because of the high energy demands of these two activities (Espie et al. 1996 and citations therein). However, representatives of at least four raptor genera are known to molt during the nesting season (Schmutz and Schmutz 1975, Newton and Marquiss 1982, Schmutz 1992, Espie et al. 1996). Molt strategies vary among raptor species depending on prey abundance, migration strategies, and the relative costs of reproduction. Sexually-dimorphic raptors typically have different roles in parenting, which result in different strategies for energy allocation. Male and female Eurasian Kestrels (Falco tinnunculus), for example, exhibit different molt patterns and mass changes during the breeding season (Village 1990). Prairie Falcons (Falco mexicanus) are similar to Eurasian Kestrels in that males provide most of the prey to females and young during the first part of the nesting season (Holthuijzen 1990), but no published data exist on molt patterns or mass changes in Prairie Falcons. Reliable information about raptor molt and morphometrics has important implications for modeling energetics and for understanding the role of sexes in raising young. Such knowledge also has practical application for distinguishing sexes of raptors and for determining appropriate size limits of transmitters used for telemetry studies. In this paper, we report on morphometric characteristics useful in distinguishing sexes of Prairie Falcons captured during several breeding seasons in the Snake River Birds of Prey National Conservation Area (NCA), and we assess changes in mass and molt status through the nesting season.

Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area

PubMed Central

2014-01-01

Background A few billion birds migrate annually between their breeding grounds in Europe and their wintering grounds in Africa. Many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. The aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in Europe as disseminators of Rickettsia-infected ticks. Methods Ticks were collected from a total of 14,789 birds during their seasonal migration northwards in spring 2009 and 2010 at bird observatories on two Mediterranean islands: Capri and Antikythira. All ticks were subjected to RNA extraction followed by cDNA synthesis and individually assayed with a real-time PCR targeting the citrate synthase (gltA) gene. For species identification of Rickettsia, multiple genes were sequenced. Results Three hundred and ninety-eight (2.7%) of all captured birds were tick-infested; some birds carried more than one tick. A total number of 734 ticks were analysed of which 353 ± 1 (48%) were Rickettsia-positive; 96% were infected with Rickettsia aeschlimannii and 4% with Rickettsia africae or unidentified Rickettsia species. The predominant tick taxon, Hyalomma marginatum sensu lato constituted 90% (n = 658) of the ticks collected. The remaining ticks were Ixodes frontalis, Amblyomma sp., Haemaphysalis sp., Rhipicephalus sp. and unidentified ixodids. Most ticks were nymphs (66%) followed by larvae (27%) and adult female ticks (0.5%). The majority (65%) of ticks was engorged and nearly all ticks contained visible blood. Conclusions Migratory birds appear to have a great impact on the dissemination of Rickettsia-infected ticks, some of which may originate from distant locations. The potential ecological, medical and veterinary implications of such Rickettsia infections need further examination. PMID:25011617

Allocation of endogenous and dietary protein in the reconstitution of the gastrointestinal tract in migratory blackcaps at stopover sites.

PubMed

Muñoz-Garcia, Agustí; Aamidor, Sarah E; McCue, Marshall D; McWilliams, Scott R; Pinshow, Berry

2012-04-01

During migratory flight, the mass of the gastrointestinal tract (GIT) and its associated organs in small birds decreases in size by as much as 40%, compared with the preflight condition because of the catabolism of protein. At stopover sites, birds need 2-3 days to rebuild their GIT so that they can restore body mass and fat reserves to continue migration. The source of protein used to rebuild the GIT may be exogenous (from food ingested) or endogenous (reallocated from other organs) or both. Because the relative contribution of these sources to rebuild the GIT of migratory birds is not yet known, we mimicked in-flight fasting and then re-feeding in two groups of blackcaps (Sylvia atricapilla), a Palearctic migratory passerine. The birds were fed a diet containing either 3% or 20% protein to simulate different refueling scenarios. During re-feeding, birds received known doses of (15)N-(l)-leucine before we measured the isotope concentrations in GIT and associated digestive organs and in locomotory muscles. We then quantified the extent to which blackcaps rebuilt their GIT with endogenous and/or dietary protein while refeeding after a fast. Our results indicate that blackcaps fed the low-protein diet incorporated less exogenous nitrogen into their tissues than birds fed the 20% protein diet. They also allocated relatively more exogenous protein to the GIT than to pectoral muscle than those birds re-fed with the high-protein diet. However, this compensation was not sufficient for birds eating the low-protein diet to rebuild their intestine at the same rate as the birds re-fed the high-protein diet. We concluded that blackcaps must choose stopover sites at which they can maximize protein intake to minimize the time it takes to rebuild their GIT and, thus, resume migration as soon as possible.

Wildlife and electric power transmission

USGS Publications Warehouse

Ellis, D.H.; Goodwin, J.G.; Hunt, J.R.; Fletcher, John L.; Busnel, R.G.

1978-01-01

Hundreds of thousands of miles of transmission lines have been introduced into our natural environment. These lines and their corridors can be damaging or beneficial to wildlife communities depending on how they are designed, where they are placed, and when they are constructed and maintained. With the current trend toward UHV systems, new problems (associated with additional increments in audible noise, electric and magnetic force fields, etc.) must be addressed. We recommend the following areas for careful study: (1) the response of wilderness species to transmission lines and line construction and maintenance activities (2) the magnitude of bird collision and electrocution mortality, (3) the response of power corridor and power tower in habiting wildlife to laboratory and field doses of electro-chemical oxidants, corona noise, electric and magnetic fields, etc., (4) the productivity of tower inhabiting birds compared with nearby non-tower nesters, and (5) the influence of powerline corridors on mammalian and avian migration patterns. It is our hope that the questions identified in this study will help stimulate further research so that we can maximize wildlife benefits and minimize wildlife detriments.

Radioactivity measurements on migrating birds (Turdus philomelos) captured in the Comunidad Valenciana (Spain).

PubMed

Navarro, E; Roldán, C; Cervera, J; Ferrero, J L

1998-01-19

The radionuclides 137Cs, 134Cs and 90Sr have been measured in edible tissues and bones of migratory birds (song-thrushes, Turdus philomelos) from central and northern Europe and captured in the Comunidad Valenciana, Spain in the 1994 autumn-winter season. Eight years after the Chernobyl accident, extensive agricultural lands in Europe are still contaminated and this study shows that there was a transfer of radioactive isotopes to the captured migratory song-thrushes. The whole-body dose commitment to humans consuming these birds is estimated.

Satellite‐tracking of Northern Pintail Anas acuta during outbreaks of the H5N1 virus in Japan: Implications for virus spread

USGS Publications Warehouse

Yamaguchi, Noriyuki; Hupp, Jerry W.; Higuchi, Hiroyoshi; Flint, Paul L.; Pearce, John M.

2010-01-01

We fitted Northern Pintail Anas acuta in Japan with satellite transmitters and monitored their spring migration movements relative to locations where the highly pathogenic H5N1 avian influenza virus was detected in Whooper Swans Cygnus cygnus in 2008. Pintails were assumed not to be infected with the H5N1 virus at the time they were marked because capture occurred between 2 and 5 months before reported outbreaks of the virus in Japan. We assessed spatial and temporal overlap between marked birds and occurrence of the virus and tracked Pintails after they departed outbreak locations. Eight of 66 (12.1%) Northern Pintails marked with satellite transmitters used wetlands in Japan where the H5N1 virus was detected in Whooper Swans. Apparent survival did not differ between Pintails that used H5N1 sites and those that did not. However, the proportion of Pintails that migrated from Japan was significantly lower among birds that used H5N1 sites compared with those that did not (0.50 vs. 0.79). Northern Pintails were present at the H5N1 sites from 1 to 88 days, with five birds present at the sites from 0 to 7 days prior to detection of the virus in Swans. The six Pintails observed to depart H5N1 sites did so within 2–77 days of the reported outbreaks and moved between 6 and 1200 km within 4 days of departure. Four Pintails migrated to eastern Russia. After their departure from outbreak sites, Northern Pintails made long‐distance migrations within the period when newly infected ducks would shed the H5N1 virus. This supports a hypothesized mechanism by which a highly pathogenic avian influenza virus could be spread by migratory birds.

Magnetic information affects the stellar orientation of young bird migrants

NASA Astrophysics Data System (ADS)

Weindler, Peter; Wiltschko, Roswitha; Wiltschko, Wolfgang

1996-09-01

WHEN young birds leave on their first migration, they are guided by innate information about their direction of migration. It is generally assumed that this direction is represented twice, namely with respect to celestial rotation and with respect to the Earth's magnetic field1,2. The interactions between the two cue systems have been analysed by exposing hand-raised young birds during the premigratory period to cue-conflict situations, in which celestial rotation and the magnetic field provided different information. Celestial rotation altered the course with respect to the magnetic field3-7, whereas conflicting magnetic information did not seem to affect the course with respect to the stars8,9. Celestial information thus seemed to dominate over magnetic information. Here we report that the interaction between the two cue systems is far more complex than this. Celestial rotation alone seems to provide only a tendency to move away from its centre (towards geographical south), which is then modified by information from the magnetic field to establish the distinctive, population-specific migratory direction.

Tracking long-distance migration to assess marine pollution impact

PubMed Central

Montevecchi, William; Fifield, David; Burke, Chantelle; Garthe, Stefan; Hedd, April; Rail, Jean-François; Robertson, Gregory

2012-01-01

Animal tracking provides new means to assess far-reaching environmental impacts. In the aftermath of the Deepwater Horizon explosion in the Gulf of Mexico, a long-distance migrant, the northern gannet (Morus bassanus) suffered the highest oiling among beach-wrecked birds recovered. Analysis of bird-borne tracking data indicated that 25 per cent of their North American population from multiple colonies in eastern Canada migrated to the pollution zone. Findings contrasted sharply with available mark-recapture (band recovery) data. The timing of movement into and out of the Gulf indicates that immature birds would have absorbed most oil-induced mortality. Consequently, one of two outcomes is likely: either a lagged (likely difficult to assess) population decrease, or an undetectable population response buffered by age-related life-history adaptations. Tracking research is especially useful when little information on animal distributions in pollution zones is available, as is the case in the Gulf of Mexico. Ongoing research highlights current risks and conservation concerns. PMID:22012949

Promoting wildness in sandhill cranes conditioned to follow an ultralight aircraft

USGS Publications Warehouse

Duff, J.W.; Lishman, W.A.; Clark, D.A.; Gee, G.F.; Sprague, D.T.; Ellis, D.H.

2001-01-01

During the 1998 field season, we developed and tested a new protocol to teach sandhill cranes (Grus canadensis) to follow ultralight aircraft yet avoid humans. Although successful in teaching the cranes a migration route, our previous migration (1997) resulted in birds that were overly tame and sought association with humans. For this study, 16 sandhill cranes were costume-reared at USGS Patuxent Wildlife Research Center and transported to Ontario shortly before fledging. After the birds learned to follow the aircraft, 14 were transported to an isolated wintering site in South Carolina, 1300 km south of the training area. Twelve arrived safely. Eleven of 12 birds survived the winter. All of these 11 cranes moved north to Cape Hatteras in early May. Thereafter, 6 of the cranes were captured and translocated to northern New York state. The remaining 5 returned to South Carolina, autumn 1999. Prior to capture, although the cranes sometimes allowed humans to approach them, none of the cranes approached buildings or humans.

Influence of Novel Highly Pathogenic Avian Influenza A (H5N1) Virus Infection on Migrating Whooper Swans Fecal Microbiota.

PubMed

Zhao, Na; Wang, Supen; Li, Hongyi; Liu, Shelan; Li, Meng; Luo, Jing; Su, Wen; He, Hongxuan

2018-01-01

The migration of wild birds plays an important role in the transmission and spread of H5 highly pathogenic avian influenza (HPAI) virus, posing a severe risk to animal and human health. Substantial evidence suggests that altered gut microbial community is implicated in the infection of respiratory influenza virus. However, the influence of H5N1 infection in gut microbiota of migratory birds remains unknown. In January 2015, a novel recombinant H5N1 virus emerged and killed about 100 migratory birds, mainly including whooper swans in Sanmenxia Reservoir Area of China. Here, we describe the first fecal microbiome diversity study of H5N1-infected migratory birds. By investigating the influence of H5N1 infection on fecal bacterial communities in infected and uninfected individuals, we found that H5N1 infection shaped the gut microbiota composition by a difference in the dominance of some genera, such as Aeromonas and Lactobacillus . We also found a decreased α diversity and increased β diversity in infectious individuals. Our results highlight that increases in changes in pathogen-containing gut communities occur when individuals become infected with H5N1. Our study may provide the first evidence that there are statistical association among H5N1 presence and fecal microbiota compositional shifts, and properties of the fecal microbiota may serve as the risk of gut-linked disease in migrates with H5N1 and further aggravate the disease transmission.

Stopover habitats of spring migrating surf scoters in southeast Alaska

USGS Publications Warehouse

Lok, E.K.; Esler, Daniel N.; Takekawa, John Y.; De La Cruz, S.W.; Sean, Boyd W.; Nysewander, D.R.; Evenson, J.R.; Ward, D.H.

2011-01-01

Habitat conditions and nutrient reserve levels during spring migration have been suggested as important factors affecting population declines in waterfowl, emphasizing the need to identify key sites used during spring and understand habitat features and resource availability at stopover sites. We used satellite telemetry to identify stopover sites used by surf scoters migrating through southeast Alaska during spring. We then contrasted habitat features of these sites to those of random sites to determine habitat attributes corresponding to use by migrating scoters. We identified 14 stopover sites based on use by satellite tagged surf scoters from several wintering sites. We identified Lynn Canal as a particularly important stopover site for surf scoters originating throughout the Pacific winter range; approximately half of tagged coastally migrating surf scoters used this site, many for extended periods. Stopover sites were farther from the mainland coast and closer to herring spawn sites than random sites, whereas physical shoreline habitat attributes were generally poor predictors of site use. The geography and resource availability within southeast Alaska provides unique and potentially critical stopover habitat for spring migrating surf scoters. Our work identifies specific sites and habitat resources that deserve conservation and management consideration. Aggregations of birds are vulnerable to human activity impacts such as contaminant spills and resource management decisions. This information is of value to agencies and organizations responsible for emergency response planning, herring fisheries management, and bird and ecosystem conservation.

Test of salt marsh as a site of production and export of fish biomass with implications for impoundment management and restoration

USGS Publications Warehouse

Stevens, Philip W.

2002-01-01

Salt marshes are among the most productive ecosystems in the world, and although they are thought to enhance the productivity of open estuarine waters, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Saltmarsh impoundments in the Indian River Lagoon, Florida, that have been reconnected to the estuary by culverts provide unique opportunities for studying marsh systems with respect to aquatic communities. The boundaries between salt marshes and the estuary are clearly defined by a system of dikes that confine fishes into a known area, and the exchange of aquatic organisms are restricted to culverts where they may be easily sampled. A multi-gear approach was used monthly to estimate fish standing stock, fish ingress/egress, and predation. Changes in saltmarsh fish abundance, and exchange with the estuary reflected the seasonal pattern of marsh flooding in the xv northern Indian River Lagoon system. During a six month period of marsh flooding, saltmarsh fishes had continuous access to marsh food resources. Piscivorous fishes regularly entered the marsh via creeks and ditches to prey upon marsh fishes, and piscivorous birds aggregated following major fish migrations to the marsh surface or to deep habitats. As water levels receded in winter, saltmarsh fishes concentrated into deep habitats and migration to the estuary ensued. The monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a biomass budget to estimate annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to be 17.7 g·m-2 salt marsh, which falls within the range of previously reported values for estuarine fish communities. The relative yields were at least 21% to piscivorous fishes, 14% to piscivorous birds, and 32% to export. Annual export of fish biomass was 5.6 g fish·m-2 salt marsh, representing about 2% of saltmarsh primary production. Saltmarsh fishes convert marsh production to high quality vagile biomass (fishes concentrate energy, protein, and nutrients as body mass) and move this readily useable production to the estuary, providing an efficient link between salt marshes and estuarine predators.

Tracking migrant songbirds with stable isotopes

Treesearch

Jeffrey F. Kelly; Deborah M. Finch

1998-01-01

Migration is a fundamental aspect of avian biology and one of the most astounding phenomena in the natural world. In North America alone there are approximately 350 species of land birds that migrate seasonally. Most of these species weigh considerably less than 50 g and travel thousands of kilometers twice annually. Migratory biology has attracted and, in no small...

Cerulean Warbler (Setophaga cerulea) spring migration stopover in northern Middle America

Treesearch

Melinda J. Welton; David L. Anderson; Gabriel J. Colorado; Paul B. Hamel; Diego Calderón-F.

2012-01-01

The Cerulean Warbler (Setophaga cerulea) has one of the longest migrations of any small passerine, traveling approximately 4,000 km between breeding grounds in eastern North America and nonbreeding residency in northern South America. However, unlike many migratory birds, little is known about this aspect of the ecology of this species. In 2004 –...

Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

USGS Publications Warehouse

Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

2013-01-01

Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

Cues, corticosterone and departure decisions in a partial migrant.

PubMed

Eikenaar, Cas; Ballstaedt, Elmar; Hessler, Sven; Klinner, Thomas; Müller, Florian; Schmaljohann, Heiko

2018-05-15

Most migrating birds make multiple stopovers to fuel and/or rest. The decision to resume migration from stopover is based on various cues, such as time within the season and wind conditions. There are hints that the strength of these departure cues shapes corticosterone level, which in its turn appears to regulate the timing of departure. We here provide results that very strongly indicate that indeed departure cues jointly shape corticosterone level of migrants at stopover. We compared corticosterone level between migrating and sedentary common blackbirds (Turdus merula) sampled simultaneously at the same location during autumn migration. As expected, in migrating individuals corticosterone level was positively associated with time within the season and with current wind conditions. The latter was only apparent in adult birds and not in 1st year migrants, thus matching the observation that 1st year autumnal migrants are less wind selective than adults. In contrast to the migrants, in sedentary blackbirds these "cues" did not explain variation in corticosterone level. Furthermore, stopover departure seemed more likely and to occur earlier in the night in migrants with high corticosterone level. Our unique comparative study thus supports the newly developed concept that corticosterone mediates between departure cues and stopover departure timing in avian migrants. Copyright © 2018 Elsevier Inc. All rights reserved.

Converging migration routes of Eurasian hobbies Falco subbuteo crossing the African equatorial rain forest.

PubMed

Strandberg, Roine; Klaassen, Raymond H G; Hake, Mikael; Olofsson, Patrik; Alerstam, Thomas

2009-02-22

Autumn migration of adult Eurasian hobbies Falco subbuteo from Europe to southern Africa was recorded by satellite telemetry and observed routes were compared with randomly simulated routes. Two non-random features of observed routes were revealed: (i) shifts to more westerly longitudes than straight paths to destinations and (ii) strong route convergence towards a restricted area close to the equator (1 degree S, 15 degrees E). The birds migrated south or southwest to approximately 10 degrees N, where they changed to south-easterly courses. The maximal spread between routes at 10 degrees N (2134 km) rapidly decreased to a minimum (67 km) close to the equator. We found a striking relationship between the route convergence and the distribution of continuous rainforest, suggesting that hobbies minimize flight distance across the forest, concentrating in a corridor where habitat may be more suitable for travelling and foraging. With rainforest forming a possible ecological barrier, many migrants may cross the equator either at 15 degrees E, similar to the hobbies, or at 30-40 degrees E, east of the rainforest where large-scale migration is well documented. Much remains to be understood about the role of the rainforest for the evolution and future of the trans-equatorial Palaearctic-African bird migration systems.

Foraging interactions of small Hawaiian forest birds

Treesearch

C. John Ralph; Barry R. Noon

1986-01-01

In a search for competition, limiting factors, and other patterns in a community of small passerine birds in Hawaii, we recorded the foraging behaviors, resource abundances, and climatic variables believed to influence resource levels. Some definite patterns were found, showing that the rare, endangered birds were specialists; however, some specialists were quite...

Transboundary pollution: Persistent organochlorine pesticides in migrant birds of the Southwestern United States and Mexico

USGS Publications Warehouse

Mora, Miguel A.

1997-01-01

The hypothesis that migratory birds accumulate persistent organochlorine pesticides (POPs) during the winter in Latin America has been prevalent for many years, particularly since 1,1,1-trichloro-2,2–bis(p-chlorophenyl)ethane (DDT) was banned in the United States in 1972. It has been suggested that peregrine falcons (Falco peregrinus), black-crowned night herons (Nycticorax nycticorax), white-faced ibises (Plegadis chihi), various migratory waterfowl and shorebirds, and other avian species accumulate higher concentrations of POPs while on migration or on their wintering grounds in Latin America. Nonetheless, the data obtained thus far are limited, and there is no clear pattern to suggest that such accumulation occurs on a widespread basis. In this review wildlife contaminant studies conducted along the U.S.-Mexico border and throughout Mexico are discussed. The results for the most part seem to indicate that no major accumulation of 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene) (DDE), the most persistent organochlorine compound, has occurred or been reported for most parts of Mexico. The majority of the DDE values in birds from Mexico were similar to those reported in birds from the southwestern United States during the same years. More work needs to be done, particularly in those cotton-producing areas of Mexico where DDT was applied heavily in the past (e.g., Chiapas and Michoacan). Because DDT is still used for malaria control and may still be used in agriculture in Chiapas, this state is probably the one where most migrant species would still be at a significant risk of increased accumulation of DDE and DDT.

Stopover ecology of a migratory ungulate

USGS Publications Warehouse

Sawyer, Hall; Kauffman, Matthew J.

2011-01-01

1. Birds that migrate long distances use stopover sites to optimize fuel loads and complete migration as quickly as possible. Stopover use has been predicted to facilitate a time-minimization strategy in land migrants as well, but empirical tests have been lacking, and alternative migration strategies have not been considered. 2. We used fine-scale movement data to evaluate the ecological role of stopovers in migratory mule deer Odocoileus hemionus— a land migrant whose fitness is strongly influenced by energy intake rather than migration speed. 3. Although deer could easily complete migrations (range 18–144 km) in several days, they took an average of 3 weeks and spent 95% of that time in a series of stopover sites that had higher forage quality than movement corridors. Forage quality of stopovers increased with elevation and distance from winter range. Mule deer use of stopovers corresponded with a narrow phenological range, such that deer occupied stopovers 44 days prior to peak green-up, when forage quality was presumed to be highest. Mule deer used one stopover for every 5∙3 and 6∙7 km travelled during spring and autumn migrations, respectively, and used the same stopovers in consecutive years. 4. Study findings indicate that stopovers play a key role in the migration strategy of mule deer by allowing individuals to migrate in concert with plant phenology and maximize energy intake rather than speed. Our results suggest that stopover use may be more common among non-avian taxa than previously thought and, although the underlying migration strategies of temperate ungulates and birds are quite different, stopover use is important to both. 5. Exploring the role of stopovers in land migrants broadens the scope of stopover ecology and recognizes that the applied and theoretical benefits of stopover ecology need not be limited to avian taxa.

Novel Reassortant Highly Pathogenic Avian Influenza (H5N8) Virus in Zoos, India

PubMed Central

Nagarajan, Shanmugasundaram; Kumar, Manoj; Murugkar, Harshad V.; Tripathi, Sushil; Shukla, Shweta; Agarwal, Sonam; Dubey, Garima; Nagi, Raunaq Singh; Singh, Vijendra Pal

2017-01-01

Highly pathogenic avian influenza (H5N8) viruses were detected in waterfowl at 2 zoos in India in October 2016. Both viruses were different 7:1 reassortants of H5N8 viruses isolated in May 2016 from wild birds in the Russian Federation and China, suggesting virus spread during southward winter migration of birds. PMID:28117031

A multi-scale examination of stopover habitat use by birds

USGS Publications Warehouse

Buler, J.J.; Moore, F.R.; Woltmann, S.

2007-01-01

Most of our understanding of habitat use by migrating land birds comes from studies conducted at single, small spatial scales, which may overemphasize the importance of intrinsic habitat factors, such as food availability, in shaping migrant distributions. We believe that a multi-scale approach is essential to assess the influence of factors that control en route habitat use. We determined the relative importance of eight variables, each operating at a habitat-patch, landscape, or regional spatial scale, in explaining the differential use of hardwood forests by Nearctic-Neotropical land birds during migration. We estimated bird densities through transect surveys at sites near the Mississippi coast during spring and autumn migration within landscapes with variable amounts of hardwood forest cover. At a regional scale, migrant density increased with proximity to the coast, which was of moderate importance in explaining bird densities, probably due to constraints imposed on migrants when negotiating the Gulf of Mexico. The amount of hardwood forest cover at a landscape scale was positively correlated with arthropod abundance and had the greatest importance in explaining densities of all migrants, as a group, during spring, and of insectivorous migrants during autumn. Among landscape scales ranging from 500 m to 10 km radius, the densities of migrants were, on average, most strongly and positively related to the amount of hardwood forest cover within a 5 km radius. We suggest that hardwood forest cover at this scale may be an indicator of habitat quality that migrants use as a cue when landing at the end of a migratory flight. At the patch scale, direct measures of arthropod abundance and plant community composition were also important in explaining migrant densities, whereas habitat structure was of little importance. The relative amount of fleshy-fruited trees was positively related and was the most important variable explaining frugivorous migrant density during autumn. Although constraints extrinsic to habitat had a moderate role in explaining migrant distributions, our results are consistent with the view that food availability is the ultimate factor shaping the distributions of birds during stopover. ?? 2007 by the Ecological Society of America.

Insect ectoparasites on wild birds in the Czech Republic during the pre-breeding period

PubMed Central

Sychra, O.; Literák, I.; Podzemný, P.; Harmat, P.; Hrabák, R.

2011-01-01

Wild passerine birds (Passeriformes) from the northeastern part of the Czech Republic were examined for ectoparasites during the pre-breeding period in 2007. Two species of fleas of the genera Ceratophyllus and Dasypsyllus (Siphonaptera: Ceratophyllidae), and 23 species of chewing lice belonging to the genera Ricinus, Myrsidea, Menacanthus (Phthiraptera: Menoponidae), Brueelia, Penenirmus, and Philopterus (Phthiraptera: Philopteridae) were found on 108 birds of 16 species. Distribution of insect ectoparasites found on wild birds during pre-breeding was compared with previous data from the post-breeding period. There was no difference in total prevalence of chewing lice in prebreeding and post-breeding periods. Higher prevalence of fleas and slightly higher mean intensity of chewing lice were found on birds during the pre-breeding period. There was a significant difference in total prevalence but equal mean intensity of chewing lice on resident and migrating birds. PMID:21395201

Human preferences for colorful birds: Vivid colors or pattern?

PubMed

Lišková, Silvie; Landová, Eva; Frynta, Daniel

2015-04-29

In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern), and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.

Monitoring breeding and migration of neotropical migratory birds at Point Loma, San Diego County, California, 5-year summary, 2011–15

USGS Publications Warehouse

Lynn, Suellen; Madden, Melanie C.; Kus, Barbara E.

2017-04-27

Executive SummaryWe operated a bird banding station on the Point Loma peninsula in western San Diego County, California, during spring and summer from 2011 to 2015. The station was established in 2010 as part of a long-term monitoring program for neotropical migratory birds during spring migration and for breeding birds as part of the Monitoring Avian Productivity and Survivorship (MAPS) program.During spring migration (April and May), 2011–15, we captured 1,760 individual birds of 54 species, 91 percent (1,595) of which were newly banded, fewer than 1 percent (3) of which were recaptures that were banded in previous years, and 9 percent (143 hummingbirds, 2 hawks, and 17 other birds) of which we released unbanded. We observed an additional 22 species that were not captured. Thirty-four individuals were captured more than once. Bird capture rate averaged 0.49 ± 0.07 captures per net-hour (range 0.41–0.56). Species richness per day averaged 6.87 ± 0.33. Cardellina pusilla (Wilson’s warbler) was the most abundant spring migrant captured, followed by Empidonax difficilis (Pacific-slope flycatcher), Vireo gilvus (warbling vireo), Zonotrichia leucophrys (white-crowned sparrow), and Selasphorus rufus (rufous hummingbird). Captures of white-crowned sparrow decreased, and captures of Pacific-slope flycatcher increased, over the 5 years of our study. Fifty-six percent of known-sex individuals were male and 44 percent were female. The peak number of new species arriving per day ranged from April 1 (2013-six species) to April 16 (2012-five species). A significant correlation was determined between the number of migrants captured each day per net-hour and the density of echoes on the Next-Generation Radar (NEXRAD) images across all 5 years, and in each year except 2014. NEXRAD radar imagery appears to be a useful tool for detecting pulses in migration.Our results indicate that Point Loma provides stopover habitat during migration for 76 migratory species, including 20 species of conservation concern. Two of these species, Vireo bellii pusillus (least Bell’s vireo) and Empidonax traillii (willow flycatcher) are listed as State and (or) federally threatened or endangered.Except for Archilochus alexandri (black-chinned hummingbird) and Setophaga occidentalis (hermit warbler), which arrived later during the migratory season in latter years of our study, median arrival dates for migratory species tended to be earlier each year or did not change across 5 years. Of the five most common migratory species, white-crowned sparrow and rufous hummingbird arrived earlier in latter years of the study, but Pacific-slope flycatcher, warbling vireo, and Wilson’s warbler median arrival dates were variable and showed no trend.We captured 1,680 individuals of 66 species during the MAPS/breeding season (May through August) across the 5 years of our study, 72 percent (1,211) of which were newly banded, 10 percent (167) of which were recaptures, and 18 percent (302 hummingbirds and other birds that escaped prior to banding) of which we released unbanded. Bird capture rate averaged 0.65 ± 0.21 captures per net-hour (range 0.12–2.54). Species richness per day ranged from 9.80 ± 5.01 to 14.20 ± 4.57. Calypte anna (Anna’s hummingbird) was the most abundant breeding species captured, followed by Oreothlypis celata (orange-crowned warbler), Psaltriparus minimus (bushtit), Pipilo maculatus (spotted towhee), Thryomanes bewickii (Bewick’s wren), Melozone crissalis (California towhee), and Chamaea fasciata (wrentit). Fifty-one percent of known-sex captures were female, and 49 percent were male. Thirty-one percent of known-age captures were juveniles.Populations of bushtits and orange-crowned warbler decreased significantly over 5 years. Anna’s hummingbird abundance was high for 4 years, and then decreased in 2015. Bewick’s wren and wrentit populations were highest in 2015. There was no obvious pattern in spotted towhee and California towhee abundance across 5 years. Annual breeding productivity for most species was low in 2014 and high in 2015. Bewick’s wren had the highest breeding productivity of the six most commonly captured species, followed by bushtit. Orange-crowned warbler had the lowest breeding productivity. Breeding productivity was a significant predictor of population size the next year for bushtit, but not for any other resident breeding species examined.Adult survivorship was generally high from 2013 to 14, and low from 2014 to 15. Wrentits had the highest survivorship of the most common species captured, followed by California towhee and orange-crowned warbler. Adult survivorship was lowest for bushtits and spotted towhees. Adult survivorship was a significant predictor of population size for bushtits, but not for any other resident species examined.Our monitoring results indicate that Point Loma provides breeding habitat for seven species of conservation concern. One of these species, the federally threatened Polioptila californica californica (California gnatcatcher), was documented breeding at the study site.

West Nile Virus in Resident Birds from Yucatan, Mexico.

PubMed

Chaves, Andrea; Sotomayor-Bonilla, Jesus; Monge, Otto; Ramírez, Abigaíl; Galindo, Francisco; Sarmiento-Silva, Rosa Elena; Gutiérrez-Espeleta, Gustavo A; Suzán, Gerardo

2016-01-01

West Nile virus (WNV) in the Americas is thought to be transported at large spatial scales by migratory birds and locally spread and amplified by resident birds. Local processes, including interspecific interactions and dominance of passerine species recognized as competent reservoirs, may boost infection and maintain endemic cycles. Change in species composition has been recognized as an important driver for infection dynamics. Due to migration and changes in species diversity and composition in wintering grounds, changes in infection prevalence are expected. To these changes, we used PCR to estimate the prevalence of WNV in wild resident birds during the dry and rainy seasons of 2012 in Yucatan, Mexico. Serum samples were obtained from 104 wild birds, belonging to six orders and 35 species. We detected WNV in 14 resident birds, representing 11 species and three orders. Prevalences by order was Passeriformes (27%), Columbiformes (6%), and Piciformes (33%). Resident birds positive to WNV from Yucatan may be indicative of local virus circulation and evidence of past virus transmission activity.

Migration patterns, use of stopover areas, and austral summer movements of Swainson's hawks

USGS Publications Warehouse

Kocher, Michael N.; Fuller, Mark R.; Schueck, Linda S.; Bond, Laura; Bechard, Marc J.; Woodbridge, Brian; Holroyd, Geoff L.; Martell, Mark S.; Banasch, Ursula

2011-01-01

from 1995 to 1998, we tracked movements of adult Swainson's Hawks (Buteo swainsoni), using satellite telemetry to characterize migration, important stopover areas, and movements in the austral summer. we tagged 46 hawks from July to September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson's Hawks followed three basic routes south on a broad front, converged along the east coast of cen-tral Mexico, and followed a concentrated corridor to a communal area in central Argentina for the austral summer. North of 20° N, southward and northward tracks differed little for individuals from east of the continental divide but differed greatly (up to 1700 km) for individuals from west of the continental divide. Hawks left the breeding grounds mid-August to mid-October; departure dates did not differ by location, year, or sex. Southbound migra-tion lasted 42 to 98 days, northbound migration 51 to 82 days. Southbound, 36% of the Swainson's Hawks departed the nesting grounds nearly 3 weeks earlier than the other radio-marked hawks and made stopovers 9.0–26.0 days long in seven separate areas, mainly in the southern great Plains, southern Arizona and New Mexico, and north-central Mexico. The birds stayed in their nonbreeding range for 76 to 128 days. All used a core area in central Ar-gentina within 23% of the 738 800-km2 austral summer range, where they frequently moved long distances (up to 1600 km). Conservation of Swainson's Hawks must be an international effort that considers habitats used during nesting and non-nesting seasons, including migration stopovers.

Ecomorphology of the external flight apparatus of blackcaps (Sylvia atricapilla) with different migration behavior.

PubMed

Fiedler, Wolfgang

2005-06-01

An analysis of the external flight apparatus of 700 blackcaps from eight different populations (sedentary to long-distance migrators) is presented. With increasing migration distances of populations, (1) wing length, aspect ratio, and wing pointedness increase; (2) wing load decreases; (3) slots on the wing tips become relatively shorter; (4) the alula tends to be shorter in relation to wing length; and (5) the tail is shorter in relation to wing length. Although body mass increases from southern to northern populations, changes in wing length and wing area are two to three times larger than expected for simple isometric relationships. Regarding the aerodynamic background of these changes, it can be stated that traits for energy-effective flight are more strongly developed and traits for maneuverability are less developed in birds traveling longer distances, presumably as a consequence of trade-offs. Nonmigratory blackcaps from Madeira and the Cape Verde islands do not always show the traits we would expect in view of their sedentary behavior. This can be seen as a result of recent colonization of these islands by migrants or of selection by factors other than migration behavior. In migratory populations, changes between the first and the second set of primaries during first complete molt show almost the same pattern as the changes from nonmigratory to migratory populations. During molt of the primaries, blackcaps of nonmigratory populations do not show these changes. Hybrids between migrating and nonmigrating blackcap populations (Moscow and Madeira) showed intermediate values between parent populations in wing length, wing shape, and wing area; in the other variables they resembled either parent population.

Organochlorine pollutants and stable isotopes in resident and migrant passerine birds from northwest Michoacán, Mexico.

PubMed

Mora, Miguel A

2008-10-01

Although concentrations of organochlorine compounds (OCs) in birds from most of the United States and Canada have decreased over the last 30 years, there is still concern that migrant birds might be exposed to elevated concentrations of OCs during migration in Latin America. The Lerma-Chapala Basin in west-central Mexico is an important migration corridor and wintering area for many species. The objectives of this study were to assess if resident and migrant birds wintering in western Michoacán, Mexico accumulated elevated concentrations of OCs during fall and spring and to determine if the stable isotopes delta(15)N, delta(13)C, and deltaD could be used to predict burdens and origins of DDE accumulation. Resident and migrant passerine insectivorous birds were collected during fall and spring (2001-2002) in northwest Michoacán, near Chapala Lake, Mexico. The carcasses were analyzed for OCs and tail feathers were analyzed for stable isotopes delta(15)N, delta(13)C, and deltaD. The OCs detected in more than 50% of the samples were: oxychlordane (79%), p,p'-DDE (100%), p,p'-DDT (57%), and total PCBs (100%). p,p'-DDE was the OC detected at the highest concentrations, whereas residues of other OCs were near or below detection limits. Overall, there were no significant differences in concentrations of OCs between seasons or between resident and migrant birds. Concentrations of DDE and oxychlordane were somewhat higher in migrant and resident birds during spring than in fall; however, concentrations were significantly different only for oxychlordane. Two resident birds collected in fall and spring had DDE residues >10 microg/g wet weight in carcass. There were no significant differences in delta(13)C and delta(15)N values among species, between seasons, or between migrant and resident birds. However, deltaD values were clearly different between species and helped differentiate migrant from resident birds. deltaD values also were negatively and significantly correlated with DDE concentrations in carcass. Birds with more depleted deltaD values in feathers tended to have higher DDE concentrations than those with less depleted deltaD values, suggesting a potential latitudinal accumulation of DDE. Overall, our results suggest that during fall and spring, there is not a significant buildup of persistent OCs in migrant and resident passerine insectivorous birds in northwest Michoacán, Mexico.

Spring-migration ecology of Northern Pintails in south-central Nebraska

USGS Publications Warehouse

Pearse, A.T.; Krapu, G.L.; Cox, R.R.; Davis, B.E.

2011-01-01

Spring-migration ecology of staging Northern Pintails, Anas acuta, was investigated in south-central Nebraska, USA. Habitat associations, local movements, settling patterns, arrival dates, residency times and survival were estimated from 71 radiomarked pintails during spring 2001, 2003 and 2004, and diet determined from 130 females collected during spring 1998 and 1999. Seventy-two percent of pintail diurnal locations were in palustrine wetlands, 7% in riverine wetlands, 3% in lacustrine wetlands, 6% in municipal sewage lagoons and irrigation reuse pits and 10.5% in croplands. Emergent wetlands with hemi-marsh conditions were used diurnally more often than wetlands with either open or closed vegetation structures. Evening foraging flights averaged 4.3 km (SE = 0.6) and 72% were to cornfields. In accord with these findings, 87% of 93 pintails collected during spring 1998 and 1999 returning to evening roosts consumed corn, which represented 84% dry mass of all foods. Pintails collected on non-cropped wetlands ingested invertebrates and seeds from wetland plants more frequently than birds returning to roost. Radiomarked pintails arrived in Nebraska on 7 March 2003 and 18 February 2004; average arrival date was six days earlier during 2004 compared to 2003. Residency time for individuals varied greatly (1-40 days) yet yearly means were similar and averaged 9.5 days within the region. No mortality was detected for 71 birds monitored over 829 exposure days. Conservation planners linking population dynamics and habitat conditions at spring-staging areas need to focus on pintail body condition during spring and its connection with reproductive success and survival during the breeding season.

Spring-migration ecology of Northern Pintails in south-central Nebraska

USGS Publications Warehouse

Pearse, Aaron T.; Krapu, Gary L.; Cox, Robert R.; Davis, Bruce E.

2011-01-01

Spring-migration ecology of staging Northern Pintails, Anas acuta, was investigated in south-central Nebraska, USA. Habitat associations, local movements, settling patterns, arrival dates, residency times and survival were estimated from 71 radiomarked pintails during spring 2001, 2003 and 2004, and diet determined from 130 females collected during spring 1998 and 1999. Seventy-two percent of pintail diurnal locations were in palustrine wetlands, 7% in riverine wetlands, 3% in lacustrine wetlands, 6% in municipal sewage lagoons and irrigation reuse pits and 10.5% in croplands. Emergent wetlands with hemi-marsh conditions were used diurnally more often than wetlands with either open or closed vegetation structures. Evening foraging flights averaged 4.3 km (SE = 0.6) and 72% were to cornfields. In accord with these findings, 87% of 93 pintails collected during spring 1998 and 1999 returning to evening roosts consumed corn, which represented 84% dry mass of all foods. Pintails collected on non-cropped wetlands ingested invertebrates and seeds from wetland plants more frequently than birds returning to roost. Radiomarked pintails arrived in Nebraska on 7 March 2003 and 18 February 2004; average arrival date was six days earlier during 2004 compared to 2003. Residency time for individuals varied greatly (1–40 days) yet yearly means were similar and averaged 9.5 days within the region. No mortality was detected for 71 birds monitored over 829 exposure days. Conservation planners linking population dynamics and habitat conditions at spring-staging areas need to focus on pintail body condition during spring and its connection with reproductive success and survival during the breeding season.

Arthropods of native and exotic vegetation and their association with willow flycatchers and Wilson's warblers

Treesearch

Linda S. DeLay; Deborah M. Finch; Sandra Brantley; Richard Fagerlund; Michael D. Means; Jeffrey F. Kelly

1999-01-01

We compared abundance of migrating Willow Flycatchers and Wilson's Warblers to the abundance of arthropods in exotic and native vegetation at Bosque del Apache National Wildlife Refuge. We trapped arthropods using glue-boards in 1996 and 1997 in the same cottonwood, saltcedar, and willow habitats where we mist-netted birds during spring and fall migration. There...

The anatomical relationships between the avian eye, orbit and sclerotic ring: implications for inferring activity patterns in extinct birds

PubMed Central

Hall, Margaret I

2008-01-01

Activity pattern, or the time of day when an animal is awake and active, is highly associated with that animal's ecology. There are two principal activity patterns: diurnal, or awake during the day in a photopic, or high light level, environment; and nocturnal, awake at night in scotopic, or low light level, conditions. Nocturnal and diurnal birds exhibit characteristic eye shapes associated with their activity pattern, with nocturnal bird eyes optimized for visual sensitivity with large corneal diameters relative to their eye axial lengths, and diurnal birds optimized for visual acuity, with larger axial lengths of the eye relative to their corneal diameters. The current study had three aims: (1) to quantify the nature of the relationship between the avian eye and its associated bony anatomy, the orbit and the sclerotic ring; (2) to investigate how activity pattern is reflected in that bony anatomy; and (3) to identify how much bony anatomy is required to interpret activity pattern reliably for a bird that does not have the soft tissue available for study, specifically, for a fossil. Knowledge of extinct avian activity patterns would be useful in making palaeoecological interpretations. Here eye, orbit and sclerotic ring morphologies of 140 nocturnal and diurnal bird species are analysed in a phylogenetic context. Although there is a close relationship between the avian eye and orbit, activity pattern can only be reliably interpreted for bony-only specimens, such as a fossil, that include both measurements of the sclerotic ring and orbit depth. Any missing data render the fossil analysis inaccurate, including fossil specimens that are flat and therefore do not have an orbit depth available. For example, activity pattern cannot be determined with confidence for Archaeopteryx lithographica, which has a complete sclerotic ring but no orbit depth measurement. Many of the bird fossils currently available that retain a good sclerotic ring tend to be flat specimens, while three-dimensionally preserved bird fossils tend not to have a well-preserved sclerotic ring or a well-defined optic foramen, necessary for delimiting the orbit depth. PMID:18510506

[Book review] The known birds of North and Middle America: Distribution and variation, migrations, changes, hybrids, etc, Part I, Hirundinidae to Mimidae, Certhiidae

USGS Publications Warehouse

Banks, Richard C.; Phillips, R.

1991-01-01

"Known Birds" is the culmination of Allan Phillips' long and productive career in elucidating the taxonomy and relationships of North American, particularly Mexican, birds. It reflects many years of largely independent work in the field, museum, and library. Although Part I includes contributions by Robert W. Dickerman, Amadeo M. Rea, and J. Dan Webster, the series (Part II will be available by the time this long-overdue review of Part I appears) reflects Phillips' views of avian systematics and his idiosyncratic scientific philosophy.

Visual guidance of forward flight in hummingbirds reveals control based on image features instead of pattern velocity.

PubMed

Dakin, Roslyn; Fellows, Tyee K; Altshuler, Douglas L

2016-08-02

Information about self-motion and obstacles in the environment is encoded by optic flow, the movement of images on the eye. Decades of research have revealed that flying insects control speed, altitude, and trajectory by a simple strategy of maintaining or balancing the translational velocity of images on the eyes, known as pattern velocity. It has been proposed that birds may use a similar algorithm but this hypothesis has not been tested directly. We examined the influence of pattern velocity on avian flight by manipulating the motion of patterns on the walls of a tunnel traversed by Anna's hummingbirds. Contrary to prediction, we found that lateral course control is not based on regulating nasal-to-temporal pattern velocity. Instead, birds closely monitored feature height in the vertical axis, and steered away from taller features even in the absence of nasal-to-temporal pattern velocity cues. For vertical course control, we observed that birds adjusted their flight altitude in response to upward motion of the horizontal plane, which simulates vertical descent. Collectively, our results suggest that birds avoid collisions using visual cues in the vertical axis. Specifically, we propose that birds monitor the vertical extent of features in the lateral visual field to assess distances to the side, and vertical pattern velocity to avoid collisions with the ground. These distinct strategies may derive from greater need to avoid collisions in birds, compared with small insects.

Patterns and predictors of β-diversity in the fragmented Brazilian Atlantic forest: a multiscale analysis of forest specialist and generalist birds.

PubMed

Morante-Filho, José Carlos; Arroyo-Rodríguez, Víctor; Faria, Deborah

2016-01-01

Biodiversity maintenance in human-altered landscapes (HALs) depends on the species turnover among localities, but the patterns and determinants of β-diversity in HALs are poorly known. In fact, declines, increases and neutral shifts in β-diversity have all been documented, depending on the landscape, ecological group and spatial scale of analysis. We shed some light on this controversy by assessing the patterns and predictors of bird β-diversity across multiple spatial scales considering forest specialist and habitat generalist bird assemblages. We surveyed birds from 144 point counts in 36 different forest sites across two landscapes with different amount of forest cover in the Brazilian Atlantic forest. We analysed β-diversity among points, among sites and between landscapes with multiplicative diversity partitioning of Hill numbers. We tested whether β-diversity among points was related to within-site variations in vegetation structure, and whether β-diversity among sites was related to site location and/or to differences among sites in vegetation structure and landscape composition (i.e. per cent forest and pasture cover surrounding each site). β-diversity between landscapes was lower than among sites and among points in both bird assemblages. In forest specialist birds, the landscape with less forest cover showed the highest β-diversity among sites (bird differentiation among sites), but generalist birds showed the opposite pattern. At the local scale, however, the less forested landscape showed the lowest β-diversity among points (bird homogenization within sites), independently of the bird assemblage. β-diversity among points was weakly related to vegetation structure, but higher β-diversity values were recorded among sites that were more isolated from each other, and among sites with higher differences in landscape composition, particularly in the less forested landscape. Our findings indicate that patterns of bird β-diversity vary across scales and are strongly related to landscape composition. Bird assemblages are shaped by both environmental filtering and dispersal limitation, particularly in less forested landscapes. Conservation and management strategies should therefore prevent deforestation in this biodiversity hotspot. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Genetic evidence of intercontinental movement of avian influenza in a migratory bird: The northern pintail (Anas acuta)

USGS Publications Warehouse

Koehler, A.V.; Pearce, J.M.; Flint, Paul L.; Franson, J.C.; Ip, Hon S.

2008-01-01

The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses confirmed the genetic divergence between Asian and North American strains of LPAI, but also suggested inter-continental virus exchange and at a higher frequency than previously documented. In 38 isolates from Alaska, nearly half (44.7%) had at least one gene segment more closely related to Asian than to North American strains of LPAI. Additionally, sequences of several Asian LPAI isolates from GenBank clustered more closely with North American northern pintail isolates than with other Asian origin viruses. Our data support the role of wild birds in the intercontinental transfer of influenza viruses, and reveal a higher degree of transfer in Alaska than elsewhere in North America. ?? 2008 The Authors.

Genetic evidence of intercontinental movement of avian influenza in a migratory bird: the northern pintail (Anas acuta).

PubMed

Koehler, Anson V; Pearce, John M; Flint, Paul L; Franson, J Christian; Ip, Hon S

2008-11-01

The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses confirmed the genetic divergence between Asian and North American strains of LPAI, but also suggested inter-continental virus exchange and at a higher frequency than previously documented. In 38 isolates from Alaska, nearly half (44.7%) had at least one gene segment more closely related to Asian than to North American strains of LPAI. Additionally, sequences of several Asian LPAI isolates from GenBank clustered more closely with North American northern pintail isolates than with other Asian origin viruses. Our data support the role of wild birds in the intercontinental transfer of influenza viruses, and reveal a higher degree of transfer in Alaska than elsewhere in North America.

Ecophysiology of avian migration in the face of current global hazards

PubMed Central

Klaassen, Marcel; Hoye, Bethany J.; Nolet, Bart A.; Buttemer, William A.

2012-01-01

Long-distance migratory birds are often considered extreme athletes, possessing a range of traits that approach the physiological limits of vertebrate design. In addition, their movements must be carefully timed to ensure that they obtain resources of sufficient quantity and quality to satisfy their high-energy needs. Migratory birds may therefore be particularly vulnerable to global change processes that are projected to alter the quality and quantity of resource availability. Because long-distance flight requires high and sustained aerobic capacity, even minor decreases in vitality can have large negative consequences for migrants. In the light of this, we assess how current global change processes may affect the ability of birds to meet the physiological demands of migration, and suggest areas where avian physiologists may help to identify potential hazards. Predicting the consequences of global change scenarios on migrant species requires (i) reconciliation of empirical and theoretical studies of avian flight physiology; (ii) an understanding of the effects of food quality, toxicants and disease on migrant performance; and (iii) mechanistic models that integrate abiotic and biotic factors to predict migratory behaviour. Critically, a multi-dimensional concept of vitality would greatly facilitate evaluation of the impact of various global change processes on the population dynamics of migratory birds. PMID:22566678

Juvenile Osprey Navigation during Trans-Oceanic Migration

PubMed Central

Horton, Travis W.; Bierregaard, Richard O.; Zawar-Reza, Peyman; Holdaway, Richard N.; Sagar, Paul

2014-01-01

To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus) are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old) of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean. PMID:25493430

Prevalence and Diversity of Low Pathogenicity Avian Influenza Viruses in Wild Birds in Guatemala, 2010-2013.

PubMed

Gonzalez-Reiche, Ana S; Müller, Maria L; Ortiz, Lucía; Cordón-Rosales, Celia; Perez, Daniel R

2016-05-01

Waterfowl species are known to harbor the greatest diversity of low pathogenicity influenza A virus (LPAIV) subtypes and are recognized as their main natural reservoir. In Guatemala there is evidence of circulation of LPAIV in wild ducks; however, the bird species contributing to viral diversity during the winter migration in Central America are unknown. In this study, samples obtained from 1250 hunter-killed birds from 22 different species were collected on the Pacific coast of Guatemala during three winter migration seasons between 2010 and 2013. Prevalence of LPAIV detected by real-time reverse-transcriptase polymerase chain reaction was 38.2%, 23.5%, and 24.7% in the 2010-11, 2011-12, and 2012-13 seasons, respectively. The highest virus prevalence was detected in the northern shoveler (Anas clypeata), followed by the blue-winged teal (Anas discors). The majority of positive samples and viral isolates were obtained from the blue-winged teal. Analysis of LPAIV prevalence over time in this species indicated a decreasing trend in monthly prevalence within a migration season. Sixty-eight viruses were isolated, and nine HA and seven NA subtypes were identified in 19 subtype combinations. In 2012-13 the most prevalent subtype was H14, a subtype identified for the first time in the Western Hemisphere in 2010. The results from this study represent the most detailed description available to date of LPAIV circulation in Central America.

Habitat selection of woodchat shrikes Lanius senator during spring stopover is related to foraging strategy

PubMed Central

Barboutis, Christos; Kassara, Christina; Giokas, Sinos

2017-01-01

Abstract Every spring a huge number of passerines cross the Sahara Desert and the Mediterranean Sea on their way to their breeding grounds. Stopover sites after such extended barriers where birds can rest, refuel, and find shelter from adverse weather, are of crucial importance for the outcome of their migration. Stopover habitat selection used by migrating birds depends on landscape context, habitat patch characteristics, as well as on the particular energetic conditions and needs of individual birds, but it is still poorly investigated. We focused on a long-distance migrating passerine, the woodchat shrike, in order to investigate for the first time the species’ habitat selection at a spring stopover site (island of Antikythira, Greece) after the crossing of the Sahara Desert and Mediterranean Sea. We implemented radio-tracking, color-ringing, and visual behavioral observations to collect data on microhabitat use. Generalized Linear Mixed Models were developed to identify the species’ most preferred microhabitat during its stopover on this low human disturbed island. We found that high maquis vegetation surrounded by low vegetation was chosen as perches for hunting. Moreover, high maquis vegetation appeared to facilitate hunting attempts toward the ground, the most frequently observed foraging strategy. Finally, we discuss our findings in the context of conservation practices for the woodchat shrike and their stopover sites on Mediterranean islands. PMID:29491971

Molt and aging criteria for four North American grassland passerines

USGS Publications Warehouse

Pyle, Peter; Jones, Stephanie L.; Ruth, Janet M.

2008-01-01

Prairie and grassland habitats in central and western North America have declined substantially since settlement by Europeans (Knopf 1994) and many of the birds and other organisms that inhabit North American grasslands have experienced steep declines (Peterjohn and Sauer 1999; Johnson and Igl 1997; Sauer, Hines, and Fallon 2007). The species addressed here, Sprague’s Pipit (Anthus spragueii), Grasshopper (Ammodramus savannarum) and Baird’s (A. bairdii) sparrows, and Chestnut-collared Longspurs (Calcarius ornatus), are grassland birds that are of special conservation concern throughout their ranges due to declining populations and the loss of the specific grassland habitats required on both their breeding and wintering ranges (Knopf 1994, Davis and Sealy 1998, Davis 2003, Davis 2004, Jones and Dieni 2007). Population-trend data on grassland birds, while clearly showing declines, provides no information on the causes of population declines. Without demographic information (i.e., productivity and survivorship), there are no means to determine when in their life cycle the problems that are creating these declines are occurring, or to determine to what extent population trends are driven by factors that affect birth rates, death rates, or both (DeSante 1995). For migratory birds, population declines may be driven by factors on breeding grounds, during migration, and/or on wintering grounds. Lack of data on productivity and survivorship thus impedes the formulation of effective management and conservation strategies to reverse population declines (DeSante 1992). Furthermore, if deficiencies in survivorship are revealed, management strategies may need to address habitats on both breeding and non-breeding grounds, as well as along migratory pathways. One technique that helps inform management strategies is the biochemical analysis of isotopes and genetic markers, from the sampling of individual feathers from live birds (Smith et al. 2003, Pérez and Hobson 2006; Appendix). Determining demographic parameters and effectively sampling feathers to reveal connectivity between breeding and wintering grounds requires detailed knowledge of molt patterns and age determination criteria for the target species, in the hand. For example, productivity, survivorship, and territory acquisition may all be age-dependent, with first-year birds showing different patterns and responses than older birds. In many cases it may be possible to sample both a feather grown on the breeding grounds and one grown on the wintering grounds from a single individual, but knowledge of age-specific molt patterns, as well as an ability to recognize different feather generations, is needed to accomplish such a task. While some information on molt and aging criteria exists for grassland passerine species (Pyle 1997a), these species have been rarely captured during mark-recapture studies (Jones et al. 2007) and this information thus needs refining. There is a need for additional resources to assist field workers in determining molt patterns and age in captured individuals. Our objective is to describe molt and aging criteria for four grassland passerine species with the aid of digital photographs taken in the field. We hope that this document will be useful for researchers studying grassland species through capture and banding of live individuals on either the breeding or the wintering grounds. We present a general section on molt and aging techniques, followed by specific accounts for the four species treated: Sprague’s Pipits, Grasshopper and Baird sparrows, and Chestnut-collared Longspur. We also provide a brief protocol on collecting feather samples (Appendix).

Nutritional condition of Pacific Black Brant wintering at the extremes of their range

USGS Publications Warehouse

Mason, D.D.; Barboza, P.S.; Ward, D.H.

2006-01-01

Endogenous stores of energy allow birds to survive periods of severe weather and food shortage during winter. We documented changes in lipid, protein, moisture, and ash in body tissues of adult female Pacific Black Brant (Branta bernicla nigricans) and modeled the energetic costs of wintering. Birds were collected at the extremes of their winter range, in Alaska and Baja California, Mexico. Body lipids decreased over winter for birds in Alaska but increased for those in Baja California. Conversely, body protein increased over winter for Brant in Alaska and remained stable for birds in Baja California. Lipid stores likely fuel migration for Brant wintering in Baja California and ensure winter survival for those in Alaska. Increases in body protein may support earlier reproduction for Brant in Alaska. Predicted energy demands were similar between sites during late winter but avenues of expenditure were different. Birds in Baja California spent more energy on lipid synthesis while those in Alaska incurred higher thermoregulatory costs. Estimated daily intake rates of eelgrass were similar between sites in early winter; however, feeding time was more constrained in Alaska because of high tides and short photoperiods. Despite differences in energetic costs and foraging time, Brant wintering at both sites appeared to be in good condition. We suggest that wintering in Alaska may be more advantageous than long-distance migration if winter survival is similar between sites and constraints on foraging time do not impair body condition. ?? The Cooper Ornithological Society 2006.

The ENSO-pandemic influenza connection: coincident or causal?

NASA Astrophysics Data System (ADS)

Shaman, J. L.; Lipsitch, M.

2011-12-01

The El Niño-Southern Oscillation (ENSO) is a coupled ocean-atmosphere system in the tropical Pacific, which affects weather conditions, including temperatures, precipitation, winds and storm activity, across the planet. ENSO has two extreme phases marked by either warmer (El Niño) or cooler (La Niña) than average sea surface temperatures in the central equatorial Pacific. We find that the 4 most recent human influenza pandemics (1918, 1957, 1968, 2009), all of which were first identified in boreal spring or summer, were preceded by La Niña conditions in the equatorial Pacific. Changes in ENSO have been shown to alter the migration, stopover time, fitness and interspecies mixing of migratory birds, and consequently likely affect their mixing with domestic animals. We hypothesize that La Niña conditions bring divergent influenza subtypes together in some parts of the world and favor the reassortment of influenza through simultaneous multiple infection of individual hosts and the generation of novel pandemic strains. We propose approaches to test this hypothesis using influenza population genetics, virus prevalence in various host species, and avian migration patterns.

Tracking through Life Stages: Adult, Immature and Juvenile Autumn Migration in a Long-Lived Seabird

PubMed Central

Péron, Clara; Grémillet, David

2013-01-01

Seasonal long-distance migration is likely to be experienced in a contrasted manner by juvenile, immature and adult birds, leading to variations in migratory routes, timing and behaviour. We provide the first analysis of late summer movements and autumn migration in these three life stages, which were tracked concurrently using satellite tags, geolocators or GPS recorders in a long-ranging migratory seabird, the Scopoli’s shearwater (formerly named Cory’s shearwater, Calonectris diomedea ) breeding on two French Mediterranean islands. During the late breeding season, immatures foraged around their colony like breeding adults, but they were the only group showing potential prospecting movements around non-natal colonies. Global migration routes were broadly comparable between the two populations and the three life stages, with all individuals heading towards the Atlantic Ocean through the strait of Gibraltar and travelling along the West African coast, up to 8000 km from their colony. However, detailed comparison of timing, trajectory and oceanographic conditions experienced by the birds revealed remarkable age-related differences. Compared to adults and immatures, juveniles made a longer stop-over in the Balearic Sea (10 days vs 4 days in average), showed lower synchrony in crossing the Gibraltar strait, had more sinuous pathways and covered longer daily distances (240 km.d-1 vs 170 km.d-1). Analysis of oceanographic habitats along migratory routes revealed funnelling selection of habitat towards coastal and more productive waters with increasing age. Younger birds may have reduced navigational ability and learn progressively fine-scale migration routes towards the more profitable travelling and wintering areas. Our study demonstrates the importance of tracking long-lived species through the stages, to better understand migratory behavior and assess differential exposure to at-sea threats. Shared distribution between life stages and populations make Scopoli’s shearwaters particularly vulnerable to extreme mortality events in autumn and winter. Such knowledge is key for the conservation of critical marine habitats. PMID:23977344

A DNA microarray for identification of selected Korean birds based on mitochondrial cytochrome c oxidase I gene sequences.

PubMed

Chung, In-Hyuk; Yoo, Hye Sook; Eah, Jae-Yong; Yoon, Hyun-Kyu; Jung, Jin-Wook; Hwang, Seung Yong; Kim, Chang-Bae

2010-10-01

DNA barcoding with the gene encoding cytochrome c oxidase I (COI) in the mitochondrial genome has been proposed as a standard marker to identify and discover animal species. Some migratory wild birds are suspected of transmitting avian influenza and pose a threat to aircraft safety because of bird strikes. We have previously reported the COI gene sequences of 92 Korean bird species. In the present study, we developed a DNA microarray to identify 17 selected bird species on the basis of nucleotide diversity. We designed and synthesized 19 specific oligonucleotide probes; these probes were arrayed on a silylated glass slide. The length of the probes was 19-24 bps. The COI sequences amplified from the tissues of the selected birds were labeled with a fluorescent probe for microarray hybridization, and unique hybridization patterns were detected for each selected species. These patterns may be considered diagnostic patterns for species identification. This microarray system will provide a sensitive and a high-throughput method for identification of Korean birds.

Wind conditions on migration influence the annual survival of a neotropical migrant, the western yellow-breasted chat (Icteria virens auricollis).

PubMed

Huang, Andrew C; Bishop, Christine A; McKibbin, René; Drake, Anna; Green, David J

2017-08-10

Long-distance migratory birds in North America have undergone precipitous declines over the past half-century. Although the trend is clear, for many migrating species underpinning the exact causes poses a challenge to conservation due to the numerous stressors that they encounter. Climate conditions during all phases of their annual cycle can have important consequences for their survival. Here, using 15 years of capture-recapture dataset, we determined the effects of various climate factors during the breeding, wintering, and migrating stages on the annual survival of a western yellow-breasted chat (Icteria virens auricollis) population breeding in southwestern Canada. El Niño effects over the entire annual cycle had little influence on the annual apparent survival of yellow-breasted chats. However, we found evidence that wind conditions during migration, specifically average westerly wind speed or the frequency of storm events, had significant adverse effects on adult annual apparent survival. In comparison, precipitation levels on wintering ground had little to no influence on adult annual apparent survival, whereas growing degree days on the breeding ground had moderate but positive effects. In the face of climate change and its predicted impacts on climate processes, understanding the influence of weather conditions on the survival of migrating birds can allow appropriate conservation strategies to be adopted for chats and other declining neotropical migrants.

Converging migration routes of Eurasian hobbies Falco subbuteo crossing the African equatorial rain forest

PubMed Central

Strandberg, Roine; Klaassen, Raymond H.G.; Hake, Mikael; Olofsson, Patrik; Alerstam, Thomas

2008-01-01

Autumn migration of adult Eurasian hobbies Falco subbuteo from Europe to southern Africa was recorded by satellite telemetry and observed routes were compared with randomly simulated routes. Two non-random features of observed routes were revealed: (i) shifts to more westerly longitudes than straight paths to destinations and (ii) strong route convergence towards a restricted area close to the equator (1° S, 15° E). The birds migrated south or southwest to approximately 10° N, where they changed to south-easterly courses. The maximal spread between routes at 10° N (2134 km) rapidly decreased to a minimum (67 km) close to the equator. We found a striking relationship between the route convergence and the distribution of continuous rainforest, suggesting that hobbies minimize flight distance across the forest, concentrating in a corridor where habitat may be more suitable for travelling and foraging. With rainforest forming a possible ecological barrier, many migrants may cross the equator either at 15° E, similar to the hobbies, or at 30–40° E, east of the rainforest where large-scale migration is well documented. Much remains to be understood about the role of the rainforest for the evolution and future of the trans-equatorial Palaearctic-African bird migration systems. PMID:18986977

Regional variation in immature Ixodes scapularis parasitism on North American songbirds: implications for transmission of the Lyme pathogen, Borrelia burgdorferi.

PubMed

Brinkerhoff, R Jory; Folsom-O'Keefe, Corrine M; Streby, Henry M; Bent, Stephen J; Tsao, Kimberly; Diuk-Wasser, Maria A

2011-03-01

Borrelia burgdorferi, the etiological agent of Lyme disease, is transmitted among hosts by the black-legged tick, Ixodes scapularis, a species that regularly parasitizes various vertebrate hosts, including birds, in its immature stages. Lyme disease risk in the United States is highest in the Northeast and in the upper Midwest where I. scapularis ticks are most abundant. Because birds might be important to the range expansion of I. scapularis and B. burgdorferi, we explored spatial variation in patterns of I. scapularis parasitism on songbirds, as well as B. burgdorferi infection in bird-derived I. scapularis larvae. We sampled birds at 23 sites in the eastern United States to describe seasonal patterns of I. scapularis occurrence on birds, and we screened a subset of I. scapularis larvae for presence of B. burgdorferi. Timing of immature I. scapularis occurrence on birds is consistent with regional variation in host-seeking activity with a generally earlier peak in larval parasitism on birds in the Midwest. Significantly more I. scapularis larvae occurred on birds that were contemporaneously parasitized by nymphs in the Midwest than the Northeast, and the proportion of birds that yielded B. burgdorferi-infected larvae was also higher in the Midwest. We conclude that regional variation in immature I. scapularis phenology results in different temporal patterns of parasitism on birds, potentially resulting in differential importance of birds to B. burgdorferi transmission dynamics among regions.

Rapid 3-week transition from migration to incubation in a female Roseate Tern (Sterna dougallii)

USGS Publications Warehouse

Spendelow, Jeffrey A.

2017-01-01

A female Roseate Tern that staged in Puerto Rico on 10 May 2008 on its migration north was first observed in the nesting area at Bird Island, Buzzards Bay, Massachusetts on 21 May. It was incubating a complete clutch of two eggs by 1 June and likely had initiated laying within 20 days of having been in Puerto Rico.

Landbird species composition and relative abundance during migration along the Rio Grande

Treesearch

Wang Yong; Deborah M. Finch

1996-01-01

In this paper, we report species composition and relative abundances of stopover migrants during spring and fall migration along the middle Rio Grande in 1994. We recorded 157 landbird species using mist-netting and survey methods at two sites on the Rio Grande, the Bosque del Apache and the Rio Grande Nature Center. A total of 6,509 birds was captured during spring...

Positive associations among riparian bird species correspond to elevational changes in plant communities

Treesearch

Deborah M. Finch

1991-01-01

Bird count data were used to characterize patterns of abundance and distribution among 20 bird species occupying streamside habitats of the central Rocky Mountains. Cluster analysis classified bird assemblages from 10 study plots into three elevational zones that varied in bird species diversity. Monotonic declines in total bird densities over the elevational gradient...