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1

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

USGS Publications Warehouse

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.

Battley, Phil F.; Warnock, Nils; Tibbitts, T. Lee; Gill, Robert E., Jr.; 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

2

SYNTHESIS OF WESTERN WILLET (Catoptrophorus semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia  

E-print Network

SYNTHESIS OF WESTERN WILLET (Catoptrophorus semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia longicauda) RESEARCH semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia longicauda) RESEARCH

3

Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific  

USGS Publications Warehouse

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.

Gill, Robert E., Jr.; Douglas, David C.; Handel, Colleen M.; Tibbitts, T. Lee; Hufford, Gary; Piersma, Theunis

2014-01-01

4

Patterns in nuclear and mitochondrial DNA reveal historical and recent isolation in the Black-tailed Godwit (Limosa limosa).  

PubMed

On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies and an absence of sub-structuring within L. l. limosa. Here, population genetic structure and phylogeographic patterns have been analyzed using COI, HVR1 and HVR2 mtDNA sequence data as well as 12 microsatellite loci (nuDNA). The nuDNA data suggest genetic differentiation between L. l. limosa from Sweden and The Netherlands, between L. l. limosa and L. l. islandica, but not between L. l. limosa and L. l. melanuroides. However, the mtDNA data were not consistent with the nuDNA pattern. mtDNA did support a split between L. l. melanuroides and L. l. limosa/L. l. islandica and also demonstrated two L. l. limosa haplotype clusters that were not geographically isolated. This genetic structure can be explained by a scenario of isolation of L. l. melanuroides from L. l. limosa in Beringia during the Last Glacial Maximum. During the Pleistocene separation of L. l. islandica from L. l. limosa occurred, followed by colonization of Iceland by the L. l. islandica during the Holocene. Within L. l. limosa founder events, followed by population expansion, took place during the Holocene also. According to the patterns observed in both markers together and their geographic separation, we propose that the three traditional subspecies indeed represent three separate genetic units. PMID:24416186

Trimbos, Krijn B; Doorenweerd, Camiel; Kraaijeveld, Ken; Musters, C J M; Groen, Niko M; de Knijff, Peter; Piersma, Theunis; de Snoo, Geert R

2014-01-01

5

Patterns in Nuclear and Mitochondrial DNA Reveal Historical and Recent Isolation in the Black-Tailed Godwit (Limosa limosa)  

PubMed Central

On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies and an absence of sub-structuring within L. l. limosa. Here, population genetic structure and phylogeographic patterns have been analyzed using COI, HVR1 and HVR2 mtDNA sequence data as well as 12 microsatellite loci (nuDNA). The nuDNA data suggest genetic differentiation between L. l. limosa from Sweden and The Netherlands, between L. l. limosa and L. l. islandica, but not between L. l. limosa and L. l. melanuroides. However, the mtDNA data were not consistent with the nuDNA pattern. mtDNA did support a split between L. l. melanuroides and L. l. limosa/L. l. islandica and also demonstrated two L. l. limosa haplotype clusters that were not geographically isolated. This genetic structure can be explained by a scenario of isolation of L. l. melanuroides from L. l. limosa in Beringia during the Last Glacial Maximum. During the Pleistocene separation of L. l. islandica from L. l. limosa occurred, followed by colonization of Iceland by the L. l. islandica during the Holocene. Within L. l. limosa founder events, followed by population expansion, took place during the Holocene also. According to the patterns observed in both markers together and their geographic separation, we propose that the three traditional subspecies indeed represent three separate genetic units. PMID:24416186

Trimbos, Krijn B.; Doorenweerd, Camiel; Kraaijeveld, Ken; Musters, C. J. M.; Groen, Niko M.; de Knijff, Peter; Piersma, Theunis; de Snoo, Geert R.

2014-01-01

6

Proceedings of the South Dakota Academy of Science,Vol. 87 (2008) 85 STATUS OF MARBLED GODWITS IN SOUTH DAKOTA  

E-print Network

& Fisheries Sciences, Brookings, SD 57007 ABSTRACT The current status of the marbled godwit (Limosa fedoa history and habitat needs. INTRODUCTION Marbled godwits (Limosa fedoa) are large sandpipers of the order

7

Effects of Management Practices on Grassland Birds: Marbled Godwit  

Microsoft Academic Search

Marbled Godwit (Limosa fedoa): Breeding range Suitable habitat Area requirements Brown-headed Cowbird brood parasitism Breeding-season phenology and site fidelity Species’ response to management Management Recommendations Habitat Characteristics

Jill A. Dechant; Marriah L. Sondreal; Douglas H. Johnson; Lawrence D. Igl; Christopher M. Goldade; Melvin P. Nenneman; Betty R. Euliss

2001-01-01

8

STATUS OF MARBLED GODWITS IN SOUTH DAKOTA: BASED ON A 2007 LITERATURE SYNTHESIS  

Microsoft Academic Search

The current status of the marbled godwit (Limosa fedoa) population in South Dakota is of primary concern to natural resource managers because the two main habitats this species needs, native rangelands and wetlands, are being converted to other land uses at a rapid rate. We synthesized over 250 references to generate a comprehensive review on the occurrence and ecology of

Dawn M. Gardner; Kent C. Jensen; Kenneth F. Higgins

2008-01-01

9

Shorebird community variations indicative of a general perturbation in the Mont-Saint-Michel bay (France)  

Microsoft Academic Search

The Mont-Saint-Michel bay located on the East Atlantic Flyway is the first site in France for wintering shorebirds, with, on average, 53000 individuals in January. Seven species represent 96% of that community: dunlin (Calidris alpina), knot (Calidris canutus), oystercatcher (Haematopus ostralegus), curlew (Numenius arquata), grey plover (Pluvialis squatarola), bar-tailed godwit (Limosa lapponica) and black-tailed godwit (Limosa limosa). The international bird

Marie-Christine Eybert; Thomas Geslin; Sophie Questiau; Eric Feunteun

2003-01-01

10

A comparison between high water and low water counts of shorebirds on the Wash, east England  

Microsoft Academic Search

Comparisons are made between counts of shorebirds at high water roosts and low water feeding grounds on the Wash, east England. During autumn and winter 1985–87, Shelduck, Tadorna tadorna, Oystercatcher, Haematopus ostralegus, Ringed Plover, Charadrius hiaticula, Grey Plover, Pluvialis squatarola, Knot, Calidris canutus, Dunlin, Calidris alpina, Bar-tailed Godwit, Limosa lapponica, Curlew, Numenius arquata Redshank, Tringa totanus and Turnstone, Arenaria interpres

M. G. Yates; J. D. Goss-Custard

1991-01-01

11

Variation in the innate and acquired arms of the immune system among five shorebird species  

Microsoft Academic Search

To contribute to an understanding of the evolutionary processes that shape variation in immune responses, we compared several components of the innate and acquired arms of the immune system in five related, but ecologically diverse, migratory shorebirds (ruff Philomachus pugnax L., ruddy turnstone Arenaria interpres L., bar-tailed godwit Limosa lapponica L., sanderling Calidris alba Pallas and red knot C. canutus

Luisa Mendes; Theunis Piersma; Dennis Hasselquist; Kevin D. Matson; Robert E. Ricklefs

2006-01-01

12

Shorebird community variations indicative of a general perturbation in the Mont-Saint-Michel bay (France).  

PubMed

The Mont-Saint-Michel bay located on the East Atlantic Flyway is the first site in France for wintering shorebirds, with, on average, 53,000 individuals in January. Seven species represent 96% of that community: dunlin (Calidris alpina), knot (Calidris canutus), oystercatcher (Haematopus ostralegus), curlew (Numenius arquata), grey plover (Pluvialis squatarola), bar-tailed godwit (Limosa lapponica) and black-tailed godwit (Limosa limosa). The international bird census organised by Wetlands International in mid-January gave us the opportunity to study, for a 23 years period, population variations in the bay. Despite a quite good carrying capacity, we showed that the decreasing proportion of 4 species in the bay relative to the other French populations may indicate a general perturbation of the bay. We discuss the different hypotheses to explain that observation. PMID:14558463

Eybert, Marie-Christine; Geslin, Thomas; Questiau, Sophie; Feunteun, Eric

2003-08-01

13

Identifying predators of eggs and chicks of Lapwing Vanellus vanellus and Black-tailed Godwit Limosa limosa in the Netherlands and the importance of predation on wader reproductive output  

Microsoft Academic Search

Farmland bird populations in the Netherlands have shown an accelerating decline in recent years, despite extensive conservation efforts including reserves, agri-environment schemes and protection of nests by volunteers. Although agricultural intensification is the main cause underlying these declines, there is a growing concern that the ongoing decline of grassland-breeding shorebirds in recent years is caused or aggravated by increasing predation.

WOLF TEUNISSEN; HANS SCHEKKERMAN; FRANK WILLEMS; FRANK MAJOOR

2008-01-01

14

Carex limosa. (A) Pistillate scales, (B) perigynia, (C) achenes, (D) inflorescences. A through C: Left--dorsal view; right--ventral view.  

E-print Network

152 Carex limosa. (A) Pistillate scales, (B) perigynia, (C) achenes, (D) inflorescences. A through C: Left--dorsal view; right--ventral view. A B C D #12;153 Carex limosa L. Mud sedge, shore sedge in Nevada (Elko County), Utah (Uinta Mountains), and Wyoming. July-August. SIMILAR SPECIES: C. limosa

15

Metabolic profile of long-distance migratory flight and stopover in a shorebird  

PubMed Central

Migrating birds often complete long non-stop flights during which body energy stores exclusively support energetic demands. The metabolic correlates of such long-distance travel in free-living migrants are as yet poorly studied. Bar-tailed godwits, Limosa lapponica taymyrensis, undertake a 4500 km flight to their single spring stopover site and thus provide an excellent model in which to determine the energy fuels associated with endurance travel. To this end, we evaluated plasma concentrations of six key metabolites in arriving godwits caught immediately upon landing near their stopover site. Initial metabolite levels were compared with levels after 5 h of inactive rest to determine how flight per se affects energy metabolism. Birds refuelling on the stopover site were also examined. Arriving godwits displayed elevated plasma free fatty acids, glycerol and butyrate, confirming the importance of lipid fuel in the support of extended migratory activity. Furthermore, elevated plasma triglycerides in these birds suggest that fatty acid provisioning is facilitated through hepatic synthesis and release of neutral lipids, as previously hypothesized for small migrants with high mass-specific metabolic rates. Finally, elevations in plasma uric acid suggest that protein breakdown contributes to the support of long-distance movement, to possibly maintain citric acid cycle intermediates, gluconeogenesis and/or water balance. PMID:15705555

Landys, M?ta M.; Piersma, Theunis; Guglielmo, Christopher G.; Jukema, Joop; Ramenofsky, Marilyn; Wingfield, John C.

2005-01-01

16

Extreme endurance flights by landbirds crossing the Pacific Ocean: Ecological corridor rather than barrier?  

USGS Publications Warehouse

Mountain ranges, deserts, ice fields and oceans generally act as barriers to the movement of land-dependent animals, often profoundly shaping migration routes. We used satellite telemetry to track the southward flights of bar-tailed godwits (Limosa lapponica baueri), shorebirds whose breeding and non-breeding areas are separated by the vast central Pacific Ocean. Seven females with surgically implanted transmitters flew non-stop 8117-11680km (10153??1043 s.d.) directly across the Pacific Ocean; two males with external transmitters flew non-stop along the same corridor for 7008-7390km. Flight duration ranged from 6.0 to 9.4 days (7.8??1.3 s.d.) for birds with implants and 5.0 to 6.6 days for birds with externally attached transmitters. These extraordinary non-stop flights establish new extremes for avian flight performance, have profound implications for understanding the physiological capabilities of vertebrates and how birds navigate, and challenge current physiological paradigms on topics such as sleep, dehydration and phenotypic flexibility. Predicted changes in climatic systems may affect survival rates if weather conditions at their departure hub or along the migration corridor should change. We propose that this transoceanic route may function as an ecological corridor rather than a barrier, providing a wind-assisted passage relatively free of pathogens and predators. ?? 2008 The Royal Society.

Gill, R.E., Jr.; Tibbitts, T.L.; Douglas, D.C.; Handel, C.M.; Mulcahy, D.M.; Gottschalck, J.C.; Warnock, N.; McCaffery, B.J.; Battley, Phil F.; Piersma, T.

2009-01-01

17

Variation in the innate and acquired arms of the immune system among five shorebird species.  

PubMed

To contribute to an understanding of the evolutionary processes that shape variation in immune responses, we compared several components of the innate and acquired arms of the immune system in five related, but ecologically diverse, migratory shorebirds (ruff Philomachus pugnax L., ruddy turnstone Arenaria interpres L., bar-tailed godwit Limosa lapponica L., sanderling Calidris alba Pallas and red knot C. canutus L.). We used a hemolysis-hemagglutination assay in free-living shorebirds to assess two of the innate components (natural antibodies and complement-mediated lysis), and a modified quantitative enzyme-linked immunosorbent assay in birds held in captivity to assess the acquired component (humoral antibodies against tetanus and diphtheria toxoid) of immunity. Ruddy turnstones showed the highest levels of both innate and acquired immune responses. We suggest that turnstones could have evolved strong immune responses because they scavenge among rotting organic material on the seashore, where they might be exposed to a particularly broad range of pathogens. Although ruffs stand out among shorebirds in having a high prevalence of avian malaria, they do not exhibit higher immune response levels. Our results indicate that relationships between immune response and infection are not likely to follow a broad general pattern, but instead depend on type of parasite exposure, among other factors. PMID:16391350

Mendes, Luisa; Piersma, Theunis; Hasselquist, Dennis; Matson, Kevin D; Ricklefs, Robert E

2006-01-01

18

Extreme endurance flights by landbirds crossing the Pacific Ocean: ecological corridor rather than barrier?  

PubMed Central

Mountain ranges, deserts, ice fields and oceans generally act as barriers to the movement of land-dependent animals, often profoundly shaping migration routes. We used satellite telemetry to track the southward flights of bar-tailed godwits (Limosa lapponica baueri), shorebirds whose breeding and non-breeding areas are separated by the vast central Pacific Ocean. Seven females with surgically implanted transmitters flew non-stop 8117–11?680?km (10?153±1043 s.d.) directly across the Pacific Ocean; two males with external transmitters flew non-stop along the same corridor for 7008–7390?km. Flight duration ranged from 6.0 to 9.4 days (7.8±1.3 s.d.) for birds with implants and 5.0 to 6.6 days for birds with externally attached transmitters. These extraordinary non-stop flights establish new extremes for avian flight performance, have profound implications for understanding the physiological capabilities of vertebrates and how birds navigate, and challenge current physiological paradigms on topics such as sleep, dehydration and phenotypic flexibility. Predicted changes in climatic systems may affect survival rates if weather conditions at their departure hub or along the migration corridor should change. We propose that this transoceanic route may function as an ecological corridor rather than a barrier, providing a wind-assisted passage relatively free of pathogens and predators. PMID:18974033

Gill, Robert E.; Tibbitts, T. Lee; Douglas, David C.; Handel, Colleen M.; Mulcahy, Daniel M.; Gottschalck, Jon C.; Warnock, Nils; McCaffery, Brian J.; Battley, Philip F.; Piersma, Theunis

2008-01-01

19

Upland Nesting Prairie Shorebirds: Use of Managed Wetland Basins and Accuracy of Breeding Surveys Utilisation de terres humides aménagées par les oiseaux de rivage des prairies nichant dans les hautes terres et précision des dénombrements d'individus nicheurs  

Microsoft Academic Search

Wetlands in southern Alberta are often managed to benefit waterfowl and cattle production. Effects on other species usually are not examined. I determined the effect of managed wetlands on upland- nesting shorebirds in southern Alberta by comparing numbers of breeding willets ( Catoptrophorus semipalmatus), marbled godwits (Limosa fedoa), and long-billed curlews ( Numenius americanus) among areas of managed wetlands, natural

Cheri L. Gratto-Trevor

20

Spring-harvested game birds in the Western James Bay region of Northern Ontario, Canada: the amount of organochlorines in matched samples of breast muscle, skin, and abdominal fat  

Microsoft Academic Search

We examined matched-tissue samples (the right pectoral muscle plus the associated skin and fat was considered a breast portion)\\u000a of 81 spring-harvested waterfowl and 19 summer-harvested godwits (Limosa spp.) to assess the potential of these water birds contributing to the body burden of PCBs and DDT noted in First Nation\\u000a people of the western James Bay region, northern Ontario, Canada.

Leonard J. S. Tsuji; Ian D. Martin; Emily S. Martin; Alain LeBlanc; Pierre Dumas

2008-01-01

21

Functional ecology of saltglands in shorebirds: Flexible responses to variable environmental conditions  

USGS Publications Warehouse

Birds of marine environments have specialized glands to excrete salt, the saltglands. Located on the skull between the eyes, the size of these organs is expected to reflect their demand, which will vary with water turnover rates as a function of environmental (heat load, salinity of prey and drinking water) and organismal (energy demand, physiological state) factors. On the basis of inter- and intraspecific comparisons of saltgland mass (m sg) in 29 species of shorebird (suborder Charadrii) from saline, fresh and mixed water habitats, we assessed the relative roles of organism and environment in determining measured m sg species. The allometric exponent, scaling dry m sg to shorebird total body mass (m b), was significantly higher for coastal marine species (0??88, N=19) than for nonmarine species (0??43, N=14). Within the marine species, those ingesting bivalves intact had significantly higher m sg than species eating soft-bodied invertebrates, indicating that seawater contained within the shells added to the salt load. In red knots (Calidris canutus), dry m sg varied with monthly averaged ambient temperature in a U-shaped way, with the lowest mass at 12??5??C. This probably reflects increased energy demand for thermoregulation at low temperatures and elevated respiratory water loss at high temperatures. In fuelling bar-tailed godwits (Limosa lapponica), dry m sg was positively correlated with intestine mass, an indicator of relative food intake rates. These findings suggest once more that saltgland masses vary within species (and presumably individuals) in relation to salt load, that is a function of energy turnover (thermoregulation and fuelling) and evaporative water needs. Our results support the notion that m sg is strongly influenced by habitat salinity, and also by factors influencing salt load and demand for osmotically free water including ambient temperature, prey type and energy intake rates. Saltglands are evidently highly flexible organs. The small size of saltglands when demands are low suggests that any time costs of adjustment are lower than the costs of maintaining a larger size in this small but essential piece of metabolic machinery. ?? 2011 The Authors. Functional Ecology ?? 2011 British Ecological Society.

Gutierrez, J.S.; Dietz, M.W.; Masero, J.A.; Gill, R.E.; Dekinga, A.; Battley, Phil F.; Sanchez-Guzman, J. M.; Piersma, T.

2012-01-01

22

Effects of management practices on grassland birds: Marbled Godwit  

USGS Publications Warehouse

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 5,500 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental components or keys to management for the species. A section on breeding range outlines the current breeding distribution of the species in North America, including areas that could not be mapped using BBS data. The suitable habitat section describes the breeding habitat and occasionally microhabitat characteristics of the species, especially those habitats that occur in the Great Plains. Details on habitat and microhabitat requirements often provide clues to how a species will respond to a particular management practice. A table near the end of the account complements the section on suitable habitat, and lists the specific habitat characteristics for the species by individual studies. A special section on prey habitat is included for those predatory species that have more specific prey requirements. The area requirements section provides details on territory and home range sizes, minimum area requirements, and the effects of patch size, edges, and other landscape and habitat features on abundance and productivity. It may be futile to manage a small block of suitable habitat for a species that has minimum area requirements that are larger than the area being managed. The Brown-headed Cowbird (Molothrus ater) is an obligate brood parasite of many grassland birds. The section on cowbird brood parasitism summarizes rates of cowbird parasitism, host responses to parasitism, and factors that influence parasitism, such as nest concealment and host density. The impact of management depends, in part, upon a species' nesting phenology and biology. The section on breeding-season phenology and site fidelity includes details on spring arrival and fall departure for migratory populations in the Great Plains, peak breeding periods, the tendency to renest after nest failure or success, and the propensity to return to a previous breeding site. The duration and timing of breeding varies among regions and years. Species' response to management summarizes the current knowledge and major findings in the literature on the effects of different management practices on the species. The section on management recommendations complements the previous section and summarizes specific recommendations for habitat management provided in the literature. If management recommendations differ in different portions of the species' breeding range, recommendations are given separately by region. The literature cited contains references to published and unpublished literature on the management effects and habitat requirements of the species. This section is not meant to be a complete bibliography; for a searchable, annotated bibliography of published and unpublished papers dealing with habitat needs of grassland birds and their responses to habitat management, use the Grassland and Wetland Birds Bibliography on the home page of this resource.

Dechant, Jill A.; Sondreal, Marriah L.; Johnson, Douglas H.; Igl, Lawrence D.; Goldade, Christopher M.; Nenneman, Melvin P.; Euliss, Betty R.

1998-01-01

23

Seasonal matching of habitat quality and fitness in a migratory bird  

PubMed Central

When species occupy habitats that vary in quality, choice of habitat can be critical in determining individual fitness. In most migratory species, juveniles migrate independently of their parents and must therefore choose both breeding and winter habitats. Using a unique dataset of marked black-tailed godwits (Limosa limosa islandica) tracked throughout their migratory range, combined with analyses of stable carbon isotope ratios, we show that those individuals that occupy higher quality breeding sites also use higher quality winter sites. This seasonal matching can severely inflate inequalities in individual fitness. This population has expanded over the last century into poorer quality breeding and winter habitats and, across the whole population; individual birds tend to occupy either novel or traditional sites in both seasons. Winter and breeding season habitat selection are thus strongly linked throughout this population; these links have profound implications for a wide range of population and evolutionary processes. As adult godwits are highly philopatric, the initial choice of winter habitat by juveniles will be critical in determining future survival, timing of migration and breeding success. PMID:16191646

Gunnarsson, Tómas Grétar; Gill, Jennifer A; Newton, Jason; Potts, Peter M; Sutherland, William J

2005-01-01

24

Impacts of man-made landscape features on numbers of estuarine waterbirds at low tide.  

PubMed

The potential impact of human disturbance on wintering waterbirds using intertidal mudflats was considered by relating their numbers to the presence of nearby footpaths, roads, railroads, and towns. Data were obtained for six English estuaries from the Wetland Bird Survey Low Tide Count scheme. Counts were undertaken monthly from November to February, and data were available for an average of 2.8 years per estuary for the period 1992-1993 to 1999-2000. Count sections and the positions of man-made landscape features were mapped using a GIS. Generalized linear models tested whether bird numbers varied according to the estuary, month, area, whether or not the section bordered water, and the proportion of each section within a specified distance of each landscape feature. In addition, the proximity of sections to the nearest footpath access point was considered. Numbers of six of nine species, northern shelduck (Tadorna tadorna), red knot (Calidris canutus), dunlin (Calidris alpina), black-tailed godwit (Limosa limosa), Eurasian curlew (Numenius arquata) and common redshank (Tringa totanus), were significantly lower where a footpath was close to a count section, while those of brant (Branta bernicla) were greater. Northern shelduck, black-bellied plover (Pluvialis squatarola), dunlin, and black-tailed godwit numbers were reduced close to railroads and those of common ringed plover (Charadrius hiaticula), black-bellied plover, and Eurasian curlew close to roads. Common ringed plover numbers were greater close to towns. The relative distances to which species were affected by footpaths corresponded to published information concerning their flight distances in response to human disturbance. The study provided evidence that sustained disturbance associated with footpaths, roads, and railroads reduced local habitat quality for waterbirds and the carrying capacity of estuaries. PMID:12402099

Burton, Niall H K; Armitage, Michael J S; Musgrove, Andrew J; Rehfisch, Mark M

2002-12-01

25

Rapid changes in phenotype distribution during range expansion in a migratory bird  

PubMed Central

The capacity of species to track changing environmental conditions is a key component of population and range changes in response to environmental change. High levels of local adaptation may constrain expansion into new locations, while the relative fitness of dispersing individuals will influence subsequent population growth. However, opportunities to explore such processes are rare, particularly at scales relevant to species-based conservation strategies. Icelandic black-tailed godwits, Limosa limosa islandica, have expanded their range throughout Iceland over the last century. We show that current male morphology varies strongly in relation to the timing of colonization across Iceland, with small males being absent from recently occupied areas. Smaller males are also proportionately more abundant on habitats and sites with higher breeding success and relative abundance of females. This population-wide spatial structuring of male morphology is most likely to result from female preferences for small males and better-quality habitats increasing both small-male fitness and the dispersal probability of larger males into poorer-quality habitats. Such eco-evolutionary feedbacks may be a key driver of rates of population growth and range expansion and contraction. PMID:21715406

Gunnarsson, Tómas Grétar; Sutherland, William J.; Alves, José A.; Potts, Peter M.; Gill, Jennifer A.

2012-01-01

26

Sex-biases in distribution and resource use at different spatial scales in a migratory shorebird  

PubMed Central

In migratory species, sexual size dimorphism can mean differing energetic requirements for males and females. Differences in the costs of migration and in the environmental conditions occurring throughout the range may therefore result in sex-biases in distribution and resource use at different spatial scales. In order to identify the scale at which sexual segregation operates, and thus the scale at which environmental changes may have sex-biased impacts, we use range-wide tracking of individually color-ringed Icelandic black-tailed godwits (Limosa limosa islandica) to quantify sexual segregation at scales ranging from the occupation of sites throughout the non-breeding range to within-site differences in distribution and resource use. Throughout the range of this migratory shorebird, there is no evidence of large-scale sex differences in distribution during the non-breeding season. However, the sexes differ in their selection of prey types and sizes, which results in small-scale sexual segregation within estuaries. The scale of sexual segregation therefore depends on the scale of variation in resource distribution, which, in this system, is primarily within estuaries. Sexual segregation in within-site distribution and resource use means that local-scale anthropogenic impacts on estuarine benthic prey communities may disproportionately affect the sexes in these migratory shorebirds. PMID:23610645

Alves, José A; Gunnarsson, Tómas G; Potts, Peter M; Sutherland, William J; Gill, Jennifer A

2013-01-01

27

Variation in numbers and behaviour of waders during the tidal cycle: implications for the use of estuarine sediment flats  

NASA Astrophysics Data System (ADS)

Estuarine sediment flats are essential feeding areas for waders, but their exploitation is constrained by the movements of tides. In this cyclic environment the exposure period of sediment flats decreases several fold from upper to lower flats, and the moving tidal waterline briefly creates particular conditions for waders and their prey. This study attempts to determine how the exposure period and the movement of the tide line influence the use of space and food resources by waders across the sediment flats. Wader counts and observations of feeding behaviour were carried out in all phases of the tidal cycle, in plots forming a transect from upper to lower flats, thus representing a gradient of exposure periods. Pecking, prey intake, and success rates varied little along the gradient. Some species actively followed the tide line while foraging, whereas others are evenly spread over the exposed flats. Black-tailed Godwit, Dunlin and Avocet were 'tide followers', whereas Grey Plover, Redshank and Bar-tailed Godwit were 'non-followers'. Densities of 'followers' near the tide line were up to five times higher than elsewhere. Species differed markedly in the way they used space on the flats, but in general the rate of biomass acquisition (in grams of ash-free dry weight per time exposed) was much higher in lower flats. However, this preference was insufficient to counter the much longer exposure of the upper flats, so the total amount of biomass consumed on the latter was greater. Therefore, it was in these upper flats that waders fulfilled most of their energetic needs. Consequently, upper flats are of particular importance for the conservation of wader assemblages, but because they are usually closer to shore they tend to suffer the highest pressure from disturbance and land reclamation.

Granadeiro, José P.; Dias, Maria P.; Martins, Ricardo C.; Palmeirim, Jorge M.

2006-05-01

28

Trace element accumulation in relation to trophic niches of shorebirds using intertidal mudflats  

NASA Astrophysics Data System (ADS)

This study investigated the link between trace element concentrations and respective diets of two shorebird species present in the Pertuis Charentais, Atlantic coast of France: the Dunlin (Calidris alpina) and Redshank (Tringa totanus). Trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Zn) were investigated in the liver, kidney, muscle and feathers of 28 dunlins and 15 redshanks accidentally dead during catches by mist net. Analyses of carbon and nitrogen stable isotope ratios were carried out in liver, muscle and feathers to determine whether differences in diet explained the variations in elemental levels. These results were compared to previous data obtained on two other shorebird species present on the same sites: the Black-tailed Godwit (Limosa limosa) and the Red Knot (Calidris canutus). This study demonstrated that shorebirds of the Pertuis Charentais were characterized by differential trace element bioaccumulation. Arsenic and Se concentrations in internal tissues were elevated in red knots and dunlins, whereas redshanks displayed higher Cd concentrations. These trace element bioaccumulation discrepancies could mainly come from divergences of trophic habits between shorebirds. Species with the highest trophic position displayed the highest Hg concentrations in the liver, muscle and feathers demonstrating therefore the biomagnification potential of this metal, as opposed to Cd and Pb. The same trend was observed in muscle and feathers for Se and only in feathers for As. These data highlighted the need to study several tissues to obtain a full comprehension of trace element exposure and pathways especially for long-distance migrating species using various habitats and sites.

Lucia, Magali; Bocher, Pierrick; Chambosse, Mélanie; Delaporte, Philippe; Bustamante, Paco

2014-09-01

29

Remote sensing aides studies of climate and wildlife in the Arctic-on land, at sea, and in the air (Invited)  

NASA Astrophysics Data System (ADS)

Every day a variety of remote sensing technologies collects large volumes of data that are supporting new analyses and new interpretations about how weather and climate influence the status and distribution of wildlife populations worldwide. Understanding how climate presently affects wildlife is crucial for projecting how climate change could affect wildlife in the future. This talk highlights climate-related wildlife studies by the US Geological Survey in the Arctic. The Arctic is experiencing some of the most pronounced climate changes on earth, raising concerns for species that have evolved seasonal migration strategies tuned to habitat availability and quality. On land, large herbivores such as caribou select concentrated calving areas with high abundance of rapidly growing vegetation and calf survival increases with earlier green-up and with the quantity of food available to cows at peak lactation. Geese time their migrations and reproductive efforts to coincide with optimal plant phenology and peak nutrient availability and departures from this synchrony can influence the survival of goslings. At sea, the habitats of polar bears and other sea-ice-dependent species have dramatically changed over just the past two decades. The ice pack is comprised of younger ice that melts much more extensively during summer-a trend projected to continue by all general circulation models under all but the most aggressive greenhouse gas mitigation scenarios. Studies show that by mid-century optimal polar bear habitats will be so reduced that the species may become extirpated from some regions of the Arctic. In the air, a variety of shorebird species make non-stop endurance flights between northern and southern hemispheres. The bar-tailed godwit undertakes a trans-Pacific flight between Alaska and Australasia that lasts more than seven days and spans more than 10,000 km. Studies show that godwits time their flights to coincide with favorable wind conditions, but stochastic weather events en route can impose energetic costs that affect reproduction and possibly survival. As more is learned about how climate and climate change affect species and ecosystems, better adaptive management decisions can be made. Remote sensing will continue to play an essential role.

Douglas, D. C.; Durner, G. M.; Gill, R. E.; Griffith, B.; Schmutz, J. A.

2013-12-01

30

Consumption of benthic fauna by carnivorous birds in the Wadden Sea  

NASA Astrophysics Data System (ADS)

Consumption by carnivorous birds was estimated for the Sylt-Rømø tidal inlet in the northern part of the Wadden Sea, as well as the subarea Königshafen, a small, tidal bay. The bird community of the Sylt-Rømø Wadden Sea was dominated by Dunlin (35% of all birds counted), Eider (9%), Oystercatcher (8%), Knot (8%), and Shelduck (7%). The community in the Königshafen was dominated by Eider (20%), Knot (17%), Bar-tailed Godwit (17%), Dunlin (13%), and Oystercatcher (8%). Annual consumption was estimated at 3.4 g AFDW · m-2 · year-1 for the entire Sylt-Rømø Wadden Sea and 19.2 g AFDW · m-2 · year-1 for the Königshafen. Restricting the calculations to the intertidal area resulted in a consumption of 8.7 g AFDW · m-2 · year-1 for the Sylt-Rømø Wadden Sea and 17.6 g AFDW · m-2 · year-1 for the Königshafen. In the two areas, consumption was dominated by the Eider with 37% and 60% of the total consumption, respectively. In comparison to the western parts of the Wadden Sea the seasonal pattern of consumption as well as species composition differed, most probably as an effect of different climatic conditions, whereas annual consumption on intertidal flats seems to be in the same order of magnitude. On average, 15 25% of the mean annual macrozoobenthic biomass seems to be taken by carnivorous birds in the Wadden Sea, which is in the same order of magnitude as in other northern temperate estuarine areas.

Scheiffarth, G.; Nehls, G.

1997-12-01

31

ARCTIC Birds of the- Northcentral Alaska Peninsula,  

E-print Network

ABSTRACT. Between spring 1976 and fall 1980 we studied the occurrence, abundance, and habitat use of birds over a 2000-km2 segment ofthe northcentral Alaska Peninsula. During this period observers were present 473 days and obtained records for all seasons. A total of 125 species was recorded; 63 % (79 of 125) were water-associated. The breeding avifauna was found to be a mixture of Panboreal (49%), North her ican (34%), and Aleutican (17%) species. The Aleutican group was dominant in terms of biomass and numbers of individuals during the nonbreeding period. Forty-two species were confirmed breeding in the area and another 19 were suspected of breeding. The majority of birds occurred as migrants; 14 species were considered permanent residents and an additional 20 were winter residents. Our observations extended the known Alaska breeding distribution of American wigeon (Anus urnericana), black turnstone (Arenuriu melanocephalu), northern phalarope (Phuluropus loburus), short-billed dowitcher (Limnodromus griseus), western sandpiper (Culidris mauri), dunlin (C. alpinu), horned puffin (Fraterculu corniculara), tufted puffin (Lundu cirrhura), and orange-crowned warbler (Vermivoru celura). Our observations also extended the known postbreeding range or significantly changed the known status of bar-tailed godwit (Limosu lupponicu), whimbrel (Numenius phueopus), lesser yellowlegs (TringaJavipes), long-billed dowitcher (Limnodromus solopuceus), dunlin (Culidris alpinu), marbled murrelet (Bruchyrumphus marmorurus), American robin (Turdus migrutorius), yellow-rumped warbler (Dendroicu coronuru), and dark-eyed junco (Junco hyemulis). The area is a principal late summer and fall molting and staging area for several species of arctic and subarctic nesting waders and seaducks and emperor geese (Anser cunagica). From late September through mid-October the density of water birds over the entire littoral and nearshore area approached loo0 birds km-2. This density was exceeded many fold for certain species on particular

Robert E. Gill; Margaret R. Petersen; Paul D. Jorgensen

1976-01-01

32

Shorebird use of an exposed sandy beach in southern California  

NASA Astrophysics Data System (ADS)

Frequent morning surveys of birds were conducted on 1 km of beach in southern California to investigate shorebird use of an exposed sandy beach. The overall mean abundance (98.6 individuals km -1), estimated biomass (9.6 kg km -1), and species richness (5.5 species km -1) of shorebirds observed were very high for a sandy beach in the temperate zone. Eight species, sanderling ( Calidris alba), semipalmated plover ( Charadrius semipalmatus), marbled godwit ( Limosa fedoa), black-bellied plover ( Pluvialis squatarola), western sandpiper ( Calidris mauri), willet ( Catoptrophorus semipalmatus), surfbird ( Aphriza virgata), and whimbrel ( Numenius phaeopus), occurred in overall mean abundances >1 bird km -1 and accounted for 97% of the abundance and biomass of shorebirds. Sanderlings were the most abundant shorebird every year (64% of individuals and 35% of the biomass). Different species of abundant shorebirds exhibited distinct patterns of use of beach habitat, including fall, spring, and winter peaks in abundance. Temporal variation in shorebird use on seasonal and interannual scales was associated with migration patterns, and also with habitat availability and condition. Seasonal variation in monthly mean abundance and estimated biomass of shorebirds varied over more than an order of magnitude and followed a similar pattern in each year, reaching maxima in the fall or winter (161-280 individuals km -1 and 15.4-23.9 kg km -1) and minima in May or June (3-11 individuals km -1 and 0.8-2.2 kg km -1). A minor peak in shorebird abundance and biomass coinciding with spring migration was observed in April of most years. The number of species of shorebirds observed in individual surveys ranged from 0 to 11 species km -1 and was positively and significantly correlated with abundance. Monthly mean species richness and the total species observed monthly followed similar seasonal patterns, ranging from annual maxima of 7.4-9.1 and 12-17 species km -1 between August and October to minima of 0.8-2.1 and 2-8 species km -1, respectively, during June. In contrast, species turnover was lowest (1.1-1.7) in October and November, and generally highest (2-4) during early summer (June). The amount of sandy intertidal habitat available to shorebirds on the transect was estimated using sand elevations and predicted tide heights. In the fall and winter, the abundance of shorebirds was significantly and positively correlated with tide height, possibly reflecting feeding opportunities and high tide refuge effects during the highest tides. In the spring when sand levels were low, the abundance of shorebirds was negatively correlated with tide height. Prey availability, beach condition and the local availability, and condition of alternative foraging habitats may influence those relationships. Interannual variations in shorebird use and beach condition were observed in the course of the study. During an El Nino Southern Oscillation (ENSO) event (1997-1998), the extent of sandy habitat was greatly reduced and intertidal habitat was mostly converted to rocky substrate. The overall abundance of shorebirds and the mean abundance of some common species (e.g. sanderling) were depressed, and an uncommon species (surfbird, A. virgata) was unusually abundant during the ENSO event. In summary, the results suggest that sandy beaches are important habitat for many species of shorebirds, particularly in areas where alternative coastal foraging habitats, such as coastal wetlands, have become scarce. Understanding the dynamics of and threats to exposed sandy beaches may be increasingly important for shorebird conservation in many coastal regions.

Hubbard, David M.; Dugan, Jenifer E.

2003-10-01

33

Carex paupercula. (A) Inflorescences, (B) pistillate scales, (C) perigynia, (D) achenes. B through D: Left--dorsal view; right--ventral view.  

E-print Network

196 Carex paupercula. (A) Inflorescences, (B) pistillate scales, (C) perigynia, (D) achenes. B through D: Left--dorsal view; right--ventral view. A B C D #12;197 Carex paupercula Michx. Little sedge SPECIES: See C. limosa. #12;

34

LIZARD BURROWS PROVIDE THERMAL REFUGIA FOR LARKS IN THE ARABIAN DESERT  

Microsoft Academic Search

A common perception is that desert birds experience greater extremes of heat and aridity than their mammalian counterparts, in part, because birds do not use burrows as a refuge from the desert envi- ronment. We report observations of Dunn's Larks (Er- emalauda dunni), Bar-tailed Desert Larks (Ammo- manes cincturus), Black-crowned Finch Larks (Ere- mopterix nigriceps), and Hoopoe Larks (Alaemon alaudipes)

JOSEPH B. WILLIAMS; B. IRENE TIELEMAN; MOHAMMED SHOBRAK

1999-01-01

35

ABUNDANCE AND DIET OF ALEXANDER'S KESTREL (mALCO TINNUNCULUS ALEXANDRI) ON BOAVISTA ISLAND (ARCHIPELAGO OF CAPE VERDE)  

Microsoft Academic Search

Alexander's Kestrel (malco tinnunculus alexandri) is an endemic resident subspecies of the Common Kestrel re- siding on Cape Verde archipelago, characterized by heavily marked upper parts and a barred tail in all plum- ages (Hazevoet 1995), which occurs only on the eastern and southern islands (Sal, Boavista, Maio, Santiago, Fogo, and Brava). The geographical distribution of the subspe- cies in

DIEGO ONTIVEROS

36

Short-term effects of reclamation of part of Seal Sands, Teesmouth, on wintering waders and Shelduck  

Microsoft Academic Search

The invertebrate macrofauna of Seal Sands, Teesmouth, is very limited in species composition. Nereis diversicolor has a two-year life cycle; the larger size-class provides the main prey of the birds Pluvialis squatarola, Numenius arquata and Limosa lapponica. Hydrobia ulvae is an important food of P. squatarola and Calidris canutus. Small Carcinus maenas occur in late autumn and are taken by

P. R. Evans; D. M. Herdson; P. J. Knights; M. W. Pienkowski

1979-01-01

37

Clonal structure and hybrid susceptibility to a smut pathogen in microscale hybrid zones of northern wetland Carex (Cyperaceae)  

Microsoft Academic Search

Interspecific hybrid taxa, especially those with the potential for clonal spread, may play important roles in community dynamics and plant-pathogen interactions. This study combines the mapping of clonal structure for two rhizomatous sedges (Carex limosa, C. rariflora ) and their nearly sterile interspecific hybrid with an investigation of the relationship between these taxa and a nonsystemic floral smut pathogen (

ELIOT J. B. MCINTIRE

2002-01-01

38

Clonal structure and hybrid susceptibility to a smut pathogen in microscale hybrid zones of northern wetland Carex (Cyperaceae).  

PubMed

Interspecific hybrid taxa, especially those with the potential for clonal spread, may play important roles in community dynamics and plant-pathogen interactions. This study combines the mapping of clonal structure for two rhizomatous sedges (Carex limosa, C. rariflora) and their nearly sterile interspecific hybrid with an investigation of the relationship between these taxa and a nonsystemic floral smut pathogen (Anthracoidea limosa) in six subarctic fens in Nouveau-Québec, Canada. We used allozyme polymorphisms in 14 of 18 putative loci to confirm hybrid identification and to distinguish among genotypes for mapping. The incidence of A. limosa was 5-20 times greater on hybrids than on parental taxa across all sites at two spatial scales (intensive extent = 10.5 m(2), extensive extent = entire fens). Spatial autocorrelation was detected in smut incidence; however, its statistical removal did not alter the strong association between hybrids and smut infection. Smut incidence on both C. limosa and hybrids was greater when they were growing in areas of high hybrid density. Our study provides evidence that disease can help maintain boundaries between species. We suggest explanations for hybrid susceptibility and provide evidence for a model in which hybrids act as a source for reinfection for all three taxa during subsequent years. PMID:21665665

McIntire, Eliot J B; Waterway, Marcia J

2002-04-01

39

Texas Rice, Volume 1, Number 8  

E-print Network

of Agriculture’s Agricultural Re- search Service, a substantial number have been evalu- ated for allelopathic effects on aquatic weeds-about 12,000 for ducksalad [Heteranthera limosa (Sw.) Willd] and around 5,000 for redstem (Ammannia coccinea Rottb.). In field...

40

[Community composition, seasonal dynamics and interspecific correlation of waterbirds in the Qiantangjiang River estuary and Hangzhou Bay].  

PubMed

Waterbird surveys were conducted regularly in the Qiantangjiang River estuary and Hangzhou Bay from July 2007 to November 2011. A total of 128 species (nine orders and 18 families) were recorded, including 119 migrants which accounted for 93% of the total species; eleven species were listed as National Protected Species. Inter-specific correlation analysis for 13 shorebird populations and nine duck populations recorded over time found that 21 pairs of shorebirds and 23 pairs of ducks were correlated. By looking at seasonal dynamics and migration patterns we were able to divide the migration process into six stages: (1) late July to late September was the migration peak of shorebirds, which were dominated by Limosa limosa, Calidris ruficollis and Charadrius mongolus. (2) Early October to mid-December was the migration peak of wintering migrants of shorebirds and ducks, which were the first two large groups in our study areas. (3) Late December to mid-February was the wintering period of migration waterbirds. (4) Late February to late March was the peak migration of ducks and the winter migrants of shorebirds dominated by Calidris alpina. (5) Early April to mid-May was the migration peak of passage migrants such as, Calidris ruficollis, Calidris acuminate and Limosa limosa but the population size of shorebird winter migrants dominated by Calidris alpine was still larger than the former. (6) Late May to mid-July was the breeding season of all egrets, summer migrants of gulls and several species of shorebirds. Our surveys show that interaction among species is possibly an important determinant of community composition of shorebirds and wintering ducks during the migration season. It may be the geographical position and community composition of migrant shorebirds across Hangzhou Bay that mean during the northward migration there are far more shorebirds than during the southward migration. PMID:22184022

Jiang, Ke-Yi; Wu, Ming; Shao, Xue-Xin

2011-12-01

41

Methane emissions from an alpine fen in central Switzerland  

Microsoft Academic Search

Methane emissions and below ground methane pore water concentrations were determined in an alpine fen at 1,915 m a.s.l. in\\u000a central Switzerland. The fen represented an acidic (pH 4.5–4.9), nutrient-poor to mesotrophic habitat dominated by Carex limosa, Carex rostrata, Trichophorum caespitosum and Sphagnum species. From late fall to late spring the fen was snow-covered. Throughout winter the temperatures never dropped below

Susanne Liebner; Simon P. Schwarzenbach; Josef Zeyer

42

Trade-off between tolerance to drought and tolerance to flooding in three wetland plants  

Microsoft Academic Search

We tested whether a trade-off exists between tolerance to flooding and tolerance to drought in wetland plants by assessing\\u000a biomass accumulation, relative growth rate (RGR), survival rate, and physiological response of three wetland plants growing\\u000a in drought or flooded environments. In wetlands of China’s Sanjiang Plain, Carex lasiocarpa typically occurs at low elevations (10–50 cm water depths), Carex limosa at

Wenbo Luo; Fengbin Song; Yonghong Xie

2008-01-01

43

Limicolen-Vorkommen an der westafrikanischen Küste auf der Banc d'Arguin (Mauretanien)  

Microsoft Academic Search

Zusammenfassung 1.Neben den Lagunen der Küste Marokkos und dem Tal des Senegal stellen die Watten und Inseln der Banc d'Arguin ein drittes wichtiges Ruhegebiet für Limicolen in West-und Nordwestafrika dar, das vor allem von Arten mit enger Bindung an das Meer aufgesucht wird:Calidris alpina, Calidris canutus, Crocethia alba, Limosa lapponica, Numenius phaeopus undArenaria interpres.2.Außer eigenen Daten im Mai 1967 konnten

Wolfgang von Westernhagen

1968-01-01

44

Structural identification of the beta-hydroxy fatty acid-based diester preen gland waxes of shorebirds.  

PubMed

The intact C33-C52 diester wax esters of the preen gland of the shorebirds Limosa lapponica, Pluvialis squatarola, and Pluvialis fulva were determined, using synthesized standards, to comprise predominantly C12-C16 beta-hydroxy fatty acids esterified with a C8-C18 fatty acid at the beta-hydroxy position and with predominantly C12-C20 fatty alcohols esterified at the carboxyl group. PMID:17960891

Rijpstra, W Irene C; Reneerkens, Jeroen; Piersma, Theunis; Damsté, Jaap S Sinninghe

2007-11-01

45

Multiple gene sequences resolve phylogenetic relationships in the shorebird suborder Scolopaci (Aves: Charadriiformes).  

PubMed

Shorebirds (Charadriiformes) are a diverse assemblage of species renowned for their variation in behavior, morphology, and life-history traits, but comparative studies of trait variation remain limited by the lack of a well-supported phylogeny based on DNA sequences. In this study we build upon previous shorebird phylogenies to construct the first sequence-based species-level phylogeny for the Scolopaci, one of three shorebird suborders. We sampled 84 species in the Scolopaci, and collected data for five genes (one nuclear and four mitochondrial) via PCR and sequencing or from GenBank. The phylogeny was estimated using Bayesian inference on a partitioned dataset of 6365 aligned base pairs, and was well-supported except for the radiations within Tringa and Calidris. The shanks and phalaropes are sister to the snipes, woodcocks and dowitchers, which in turn are sister to the sandpipers. The godwits and curlews are successive sister-groups to these clades, and the morphologically disparate taxa (jacanas, painted snipes, seedsnipes, and the Plains-wanderer) are the basal sister-group in the Scolopaci. We show that Tringa, Gallinago, and Calidris are paraphyletic assemblages, and thus are in need of taxonomic revision. The clade of Calidridine sandpipers has very short internal branches indicative of a relatively recent rapid radiation, and will require a gene tree/species tree approach to resolve relationships among species. PMID:22491071

Gibson, Rosemary; Baker, Allan

2012-07-01

46

Morphodynamically-based sediment budget in gravel-bed rivers: methodological problems (Invited)  

NASA Astrophysics Data System (ADS)

Estimation of the bed-material sediment budget from morphological changes has been adopted as an acceptable practice for gravel-bed rivers in which trends of morphological change persist for some considerable period. The qualification is important: co-located erosion and deposition within a survey interval biases the result. Another source of significant bias that has not generally been noted is the ';two-speed' nature of the fluvial sediment system by which sand moves through a reach much more quickly than gravel. Resident sand occurs in particular sedimentary environments (e.g., bar tail) and as cover sands - sometimes extensively so - in addition to forming gravel matrix. These materials are readily entrained during high flows and may constitute a large proportion of mobile sediment during flood. Unless explicitly accounted for in end-point assessments, they may significantly bias the gravel budget. Furthermore, they may easily be replaced during a single flood event, introducing the problem of co-located exchange. In Fraser River, British Columbia, a large gravel-bed river that appears suitable for sediment budget calculations by morphodynamic methods, an attempt is being made to understand this problem by mapping surficial sand using hyperspatial air photography and assessing its volume by application of a distribution of sand depths. The volume of these deposits may thereby be separately estimated and discounted in the assessments of changing gravel storage.

Church, M. A.

2013-12-01

47

Isoprene emission from a subarctic peatland under enhanced UV-B radiation.  

PubMed

Isoprene is a reactive hydrocarbon with an important role in atmospheric chemistry, and emissions from vegetation contribute to atmospheric carbon fluxes. The magnitude of isoprene emissions from arctic peatlands is not known, and it may be altered by increasing UV-B radiation. Isoprene emission was measured with the dynamic chamber method from a subarctic peatland under long-term enhancement of UV-B radiation targeted to correspond to a 20% loss in the stratospheric ozone layer. The site type of the peatland was a flark fen dominated by the moss Warnstorfia exannulata and sedges Eriophorum russeolum and Carex limosa. The relationship between species densities and the emission was also assessed. Isoprene emissions were significantly increased by enhanced UV-B radiation during the second (2004) and the fourth (2006) growing seasons under the UV-B exposure. Emissions were related to the density of E. russeolum. The dominant moss, W. exannulata, proved to emit small amounts of isoprene in a laboratory trial. Subarctic fens, even without Sphagnum moss, are a significant source of isoprene to the atmosphere, especially under periods of warm weather. Warming of the Arctic together with enhanced UV-B radiation may substantially increase the emissions. PMID:17888116

Tiiva, Päivi; Rinnan, Riikka; Faubert, Patrick; Räsänen, Janne; Holopainen, Toini; Kyrö, Esko; Holopainen, Jarmo K

2007-01-01

48

Avian assemblages on altered grasslands  

USGS Publications Warehouse

Grasslands comprise 17% of the North American landscape but provide primary habitat for only 5% of native bird species. On the Great Plains, grasslands include an eastern component of tall grasses and a western component of short grasses, both of which have been regionally altered by removing native grazers, plowing sod, draining wetlands, and encouraging woody vegetation. As a group, populations of endemic bird species of the grasslands have declined more than others (including neotropical migrants) in the last quarter century. Individually, populations of the Upland Sandpiper and McCown’s Longspur have increased; the wetlands-associated Marbled Godwit and Wilson’s Phalarope appear stable; breeding ranges are shifting for the Ferruginous Hawk, Mississippi Kite, Short-eared Owl, Upland Sandpiper, Horned Lark, Vesper, Savannah, and Henslow’s sparrows, and Western Meadowlark; breeding habitats are disappearing locally for Franklin’s Gull, Dickcissel, Henslow’s and Grasshopper sparrows. Lark Bunting, and Eastern Meadowlark; and populations are declining throughout the breeding ranges for Mountain Plover, and Cassin’s and Clay-colored sparrows. Declines of these latter three species, and also the Franklin’s Gull, presumably are due to ecological phenomena on their respective wintering areas. Unlike forest species that winter in the neotropics, most birds that breed in the North American grasslands also winter on the continent and problems driving declines in grassland species are associated almost entirely with North American processes. Contemporary programs and initiatives hold promise for the conservation of breeding habitats for these birds. Ecological ignorance of wintering habits and habitats clouds the future of the endemic birds of grasslands, especially those currently experiencing widespread declines across breeding locales.

Knopf, Fritz L.

1994-01-01

49

Goals and objectives  

USGS Publications Warehouse

We report results from shorebird surveys in the North American Arctic, defined here as Bird Conservation Regions 2 and 3 of the North American Bird Conservation Initiative (http://www.nabci.net/International/English/bcrmap.html). The surveys estimate population size and trend, and provide information on habitat relationships, at the regional and Arctic-wide scale (Table 1, Fig 1). Of the 53 species of shorebirds that breed in the United States and Canada, 26 (47%) breed in the arctic in sufficient numbers that arctic surveys are an important part of monitoring programs for them (Brown et al. 2001, Donaldson et al. 2000; Table 1). Arctic-breeding shorebirds are a diverse group that exhibits a wide range of migration, reproductive, and wintering strategies (Table 1.1). Some species migrate a short distance to the northern United States and southern Canada (e.g. Purple Sandpiper; for scientific names, see Appendix D), while others undertake epic migrations to West Africa (e.g. Red Phalarope) or southern South America (e.g. Hudsonian Godwit, Red Knot). Some migrate in huge flocks, while others trickle south singly or in small groups. There are monogamous, polygamous, and polyandrous breeders, and most habitats in the Arctic provide nesting opportunities for shorebird species. Despite their different life history characteristics, all Arctic shorebird species share two traits: 1) they are all are migrants (none inhabit the Arctic year-round) and 2) because of their migratory behavior, all are exposed to anthropogenic hazards at some point(s) in their life cycle.

Bart, Jonathan; Johnston, Victoria

2012-01-01

50

Ground-based LiDAR to investigate landscape engineering by woody riparian trees  

NASA Astrophysics Data System (ADS)

Plant-scale disruption to flow can result in upstream scour and downstream deposition, creating 'tail bars'. Tail bars have been postulated to exhibit airfoil geometries that reduce drag, causing a positive feedback whereby additional deposition of sediment results in growth of pioneer islands. We quantify the relative influence of vegetation morphology and grain size on morphodynamics by using ground-based LiDAR to scan trees and associated scour and tail bar features. We scanned trees of various growth stages and morphologies (Populus and Tamarix) in both sand- and gravel-bed settings. We post-process vegetation scans for hydrodynamic vegetation density, a proxy for leaf area index that we use in stress partitioning calculations to compare the magnitude of grain versus vegetation roughness. We also quantify the dimensions of upstream scour (maximum depth and volume) and downstream tail bar deposits (maximum height, width, length, volume). The vegetation and ground scans will be used to evaluate whether scour and tail bar geometries can be predicted from hydrodynamic vegetation density, and whether tail bars exhibit airfoil geometries in a manner that reduces drag. Field observations indicate single-stem trees (e.g. Populus) produce greater upstream scour but more subdued tail bar deposits, whereas multi-stem trees (e.g. Tamarix) produce less upstream scour but more tail bar deposition. Scour and tail bar features are more dramatic in the sand-bed setting compared to the gravel-bed, where grain roughness may play a larger role. Our research quantifies the magnitude of vegetation-morphodynamic feedbacks, with implications for plant community and landscape evolution in a multitude of riverine settings.

Bywater-Reyes, S.; Wilcox, A. C.; Manners, R.; Lightbody, A.

2013-12-01

51

Liparis loeselii (L.) L.C.Rich bog twayblade Orchidaceae (Orchid Family) Liparis loeselii bog twayblade Status: State Endangered  

E-print Network

General Description: Plant with two large basal leaves with parallel venation; flower stalk 3-8 inches tall; flowers white to yellowish-green; sepals 3/16 to 5/16 inch, 3-nerved; petals 1-nerved, 3/16 to 1/4 inch; lip 3/16 to 1/4 inch, oblong-oval, abruptly acute and with a narrow base, curved downward, 5-7 veined. The use of a technical key is recommended for positive identification. Identification Tips: This is the only Liparis which occurs in WA. The other genera which are at least superficially similar include Listera and Platanthera. The former all have leaves that are borne near midlength of the stem, rather than essentially at the base. The latter have a spur on the lowermost petal (the lip). Phenology: This species is identifiable in June. Range: Nova Scotia to Alabama, very sporadically to Saskatchewan, North Dakota, and Iowa. Also occurs in Europe. Disjunct in WA, occurring in the Eastern Cascades and Puget Trough physiographic provinces. Habitat: The species occurs around springs, in bogs, and wet sunny places within Douglas fir dominated forests in WA. Associated species include red alder (Alnus rubra), salmonberry (Rubus spectabilis), hardhack (Spirea douglasii), adder’s tongue (Ophioglossum vulgatum), skunk cabbage (Lysichitum americanum), mountain alder (Alnus incana), bog willow (Salix pedicellaris), mud sedge (Carex limosa), slender sedge (Carex lasiocarpa), roundleaf sundew (Drosera rotundifolia), common buckbean (Menyanthes trifoliata), swamp laurel (Kalmia occidentalis), trailing St. John’s wort (Hypericum anagalloides), marsh cinquefoil (Potentilla palustris), and Baltic rush (Juncus balticus).

Rank Gs

52

Mechanisms of point bar growth and accretion in experimental bedload-dominated streams  

NASA Astrophysics Data System (ADS)

As channels migrate across their floodplains they erode their outer banks and create new floodplain on their inner bank via deposition of a point bar. While there has been considerable work on flow through bends and on erosion of the outer bank, there has been comparatively little study of the mechanisms of lateral point bar growth and accretion. We hypothesize that if slope and discharge are sufficient for meandering channels, meandering requires three additional conditions: (1) increased bank strength so that bar growth can keep pace with bank erosion; (2) overbank flows so the point bar can grow to the elevation of the floodplain; and (3) finer (suspendable) particles to allow the point bar to attach to the floodplain downstream of the bar apex. The first condition stems from experiments conducted with the same bed and bank material without sprouts that resulted in a braided morphology and observations of characteristics of meandering channels in the field. The second condition arises because sediment deposition to the elevation of the floodplain requires flow depth that exceeds the elevation of floodplain. The last condition emerges from the strong tendency for the downstream tail of point bars to form a ridge away from the inner bank and leave a trough where bedload sediment doesn't enter. These hypotheses are based on initial single bend experiments in a 3.7 m by 6.1 m flume with a slope of 0.005 that uses alfalfa sprouts to provide bank strength. New experiments are now underway using a 6.1 m wide and 16.5 m long flume with a valley slope of 0.004. The initial channel is set to 1.9 cm deep and 40 cm wide. As before, we have used alfalfa sprouts to increase the bank strength and reduce the bank erosion rate. The previous experiments consisted of two runs with 4 discharges ranging from the critical flow for the initiation of sediment transport to a flow double bankfull. In the experiments in the larger basin, we will use a two-stage hydrograph with a long-duration bankfull flow and a shorter-duration overbank flow. Our goal is to model a meandering gravel bedded stream, which puts particular emphasis on the availability of finer sediment to bridge the gap between the bar tail and the floodplain. Here we use two sediment types to represent gravel and sand. The model gravel was sand with a median size of 0.85 mm and a specific gravity of 2.66. We used plastic sediment with a median size of 370 microns and specific gravity of 1.5 as the model sand. The lower specific gravity allows the plastic to be re-entrained more easily than denser particles with the same settling velocity. We anticipate being able to develop four bends, with the lower ones evolving to cutoff. Initial experiments without plastic were able to connect the bar to the floodplain upstream of the bar apex but the trough remained downstream of the bar apex. Subsequent test runs with both plastic and sand showed that the plastic was able to deposit where the trough formed downstream of the bar apex.

Braudrick, C. A.; Leverich, G.; Dietrich, W. E.; Sklar, L.

2006-12-01

53

Constructing a Baseline Model of Alpine Wetlands of the Uinta Mountains, Utah, USA  

NASA Astrophysics Data System (ADS)

Alpine wetlands of the Uinta Mountains, northeastern Utah, contain a variety of groundwater-dependent ecosystems. Unlike their counterparts in other areas of the Rocky Mountains, these systems have been relatively unstudied. The Reader Lakes area on the southern slope of the range was selected for detailed study because of its variety of wetland plant communities, homogenous bedrock geology, and minimal human impact. The primary goal of this interdisciplinary study is to establish the functional links between the geomorphology and hydrogeology of these high mountain wetlands and their constituent plant communities. In addition to traditional field studies and water chemistry, geospatial technologies are being used to organize and analyze both field data (water chemistry and wetland vegetation) and archived multispectral imagery (2006 NAIP images). The hydrology of these wetlands is dominated by groundwater discharge and their surface is dominated by string-and-flark morphology of various spatial scales, making these montane wetlands classic patterned fens. The drainage basin is organized into a series of large-scale stair-stepping wetlands, bounded by glacial moraines at their lower end. Wetlands are compartmentalized by a series of large strings (roughly perpendicular to the axial stream) and flarks. This pattern may be related to small ridges on the underlying ground moraine and possibly modified by beaver activity along the axial stream. Small-scale patterning occurs along the margins of the wetlands and in sloping-fen settings. The smaller-scale strings and flarks form a complex; self-regulating system in which water retention is enhanced and surface flow is minimized. Major plant communities have been identified within the wetlands for example: a Salix planifolia community associated with the peaty strings; Carex aquatilis, Carex limosa, and Eriophorum angustifolium communities associated with flarks; as well as a Sphagnum sp.- rich hummocky transition zone between wetland and non-wetland areas. On-going analyses of water-chemistry data will be used to identify discrete water sources and to characterize the degree of horizontal and vertical water mixing within the system, as well as to help identify the biochemical requirements of the different plant communities. Results indicate that the chemical composition of the main creek reflects the accumulative effect that the peaty flarks have on the creek as it passes through the wetland system, with pH overall decreasing from 7.3 to 7.0, dissolved oxygen decreasing from 9400 to 8400 micrograms per liter and total dissolved solids increasing from 9 mg/L to 13 mg/L. String ground water is characterized by relatively high pH (ranging from 6.0 to 7.1), high oxidizing-reducing potential (ORP) (ranging from 50 mV to 180 mV), high dissolved oxygen (from 2500 ?g/L to 9600 ?g /L) while flark ground water has relatively lower pH (5.6 to 6.8), low oxidizing reducing potential (ORP) (ranging from -66 mV to 150 mV), low dissolved oxygen (from 900 ?g /L to 9000 ?g /L).

Matyjasik, M.; Ford, R. L.; Bartholomew, L. M.; Welsh, S. B.; Hernandez, M.; Koerner, D.; Muir, M.

2008-12-01