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Sample records for gaviota cangrejera larus

  1. Monitoring organic contaminants in eggs of glaucous and glaucous-winged gulls (Larus hyperboreus and Larus glaucescens) from Alaska.

    PubMed

    Vander Pol, Stacy S; Becker, Paul R; Ellisor, Michael B; Moors, Amanda J; Pugh, Rebecca S; Roseneau, David G

    2009-03-01

    Gull eggs have been used to monitor contaminants in many parts of the world. The Seabird Tissue Archival and Monitoring Project (STAMP) is a long-term program designed to track trends in pollutants in northern marine environments using seabird eggs. Glaucous and glaucous-winged gull (Larus hyperboreus and Larus glaucescens) eggs collected in 2005 from seven Alaskan colonies were analyzed for organic contaminants. Concentrations ranged from below detection limits to 322 ng g(-1) wet mass in one egg for 4,4'-DDE and differed among the samples collected in the Gulf of Alaska and Bering and Chukchi Seas. Chick growth and survival rates may be affected by the contaminant levels found in the eggs, but the eggs should be safe for human consumption if they are eaten in small quantities. STAMP plans to continue collecting and banking gull eggs for future real-time and retrospective analyses.

  2. The Whole AMS Matrix: Using the Owens Lake, Ardath Slump, and Gaviota Slide cores to explore classification of ellipsoid shapes

    NASA Astrophysics Data System (ADS)

    Schwehr, K.; Driscoll, N.; Tauxe, L.

    2004-12-01

    Categorizing sediment history using Anisotropy of Magnetic Susceptibility (AMS) has been a long standing challenge for the paleomagnetic community. The goal is to have a robust test of shape fabrics that allows workers to classify sediments in terms of being primary depositional fabric, deposition in with currents, or altered fabrics. Additionally, it is important to be able to distinguish altered fabrics into such classes as slumps, crypto-slumps, drilling deformation (such as fluidization from drilling mud and flow-in), and so forth. To try to bring a unified test scheme to AMS interpretation, we are using three example test cases. First is the Owens Lake OL92 core, which has provided previous workers with a long core example in a lacustrian environment. OL92 was classified into five zones based on visual observations of the core photographs. Using these groupings, Rosenbaum et al. (2000) was able to use the deflection of the minimum eigen vector from vertical to classify each individual AMS sample. Second is the Ardath Shale location, which provides a clear case of a lithified outcrop scale problem that showed success with the bootstrap eigen value test. Finally is the Gaviota Slide in the Santa Barbara Basin, which provides usage of 1-2 meter gravity cores. Previous work has focused on Flinn, Jelinek, and bootstrap plots of eigen values. In supporting the shape characterization we have also used a 95% confidence F-Test by means of Hext's statistical work. We have extended the F-Test into a promising new plot of the F12 and F23 confidence values, which shows good clustering in early tests. We have applied all of the available techniques to the above three test cases and will present how each technique either succeeds or fails. Since each method has its own strengths and weaknesses, it is clear that the community needs to carefully evaluate which technique should be applied to any particular problem.

  3. Extensive mitochondrial introgression in North American Great Black-backed Gulls (Larus marinus) from the American Herring Gull (Larus smithsonianus) with little nuclear DNA impact.

    PubMed

    Pons, J-M; Sonsthagen, S; Dove, C; Crochet, P-A

    2014-03-01

    Recent genetic studies have shown that introgression rates among loci may greatly vary according to their location in the genome. In particular, several cases of mito-nuclear discordances have been reported for a wide range of organisms. In the present study, we examine the causes of discordance between mitochondrial (mtDNA) and nuclear DNA introgression detected in North American populations of the Great Black-backed Gull (Larus marinus), a Holarctic species, from the Nearctic North American Herring Gull (Larus smithsonianus). Our results show that extensive unidirectional mtDNA introgression from Larus smithsonianus into Larus marinus in North America cannot be explained by ancestral polymorphism but most likely results from ancient hybridization events occurring when Larus marinus invaded the North America. Conversely, our nuclear DNA results based on 12 microsatellites detected very little introgression from Larus smithsonianus into North American Larus marinus. We discuss these results in the framework of demographic and selective mechanisms that have been postulated to explain mito-nuclear discrepancies. We were unable to demonstrate selection as the main cause of mito-nuclear introgression discordance but cannot dismiss the possible role of selection in the observed pattern. Among demographic explanations, only drift in small populations and bias in mate choice in an invasive context may explain our results. As it is often difficult to demonstrate that selection may be the main factor driving the introgression of mitochondrial DNA in natural populations, we advocate that evaluating alternative demographic neutral hypotheses may help to indirectly support or reject hypotheses invoking selective processes.

  4. Extensive mitochondrial introgression in North American Great Black-backed Gulls (Larus marinus) from the American Herring Gull (Larus smithsonianus) with little nuclear DNA impact

    PubMed Central

    Pons, J-M; Sonsthagen, S; Dove, C; Crochet, P-A

    2014-01-01

    Recent genetic studies have shown that introgression rates among loci may greatly vary according to their location in the genome. In particular, several cases of mito-nuclear discordances have been reported for a wide range of organisms. In the present study, we examine the causes of discordance between mitochondrial (mtDNA) and nuclear DNA introgression detected in North American populations of the Great Black-backed Gull (Larus marinus), a Holarctic species, from the Nearctic North American Herring Gull (Larus smithsonianus). Our results show that extensive unidirectional mtDNA introgression from Larus smithsonianus into Larus marinus in North America cannot be explained by ancestral polymorphism but most likely results from ancient hybridization events occurring when Larus marinus invaded the North America. Conversely, our nuclear DNA results based on 12 microsatellites detected very little introgression from Larus smithsonianus into North American Larus marinus. We discuss these results in the framework of demographic and selective mechanisms that have been postulated to explain mito-nuclear discrepancies. We were unable to demonstrate selection as the main cause of mito-nuclear introgression discordance but cannot dismiss the possible role of selection in the observed pattern. Among demographic explanations, only drift in small populations and bias in mate choice in an invasive context may explain our results. As it is often difficult to demonstrate that selection may be the main factor driving the introgression of mitochondrial DNA in natural populations, we advocate that evaluating alternative demographic neutral hypotheses may help to indirectly support or reject hypotheses invoking selective processes. PMID:24105440

  5. Dechlorane Plus in eggs of two gull species (Larus michahellis and Larus audouinii) from the southwestern Mediterranean Sea.

    PubMed

    Muñoz-Arnanz, Juan; Roscales, Jose Luis; Vicente, Alba; Aguirre, Jose Ignacio; Jiménez, Begoña

    2012-11-01

    Dechlorane Plus (DP) and some of its possible degradation products were measured in eggs from the yellow-legged gull (Larus michahellis) and Audouin's gull (Larus audouinii) from a protected area in the southwestern Mediterranean Sea. Statistically significant differences were found between both gull species, with yellow-legged gull eggs showing the highest average total DP concentration (209 pg/g wet weight). According to stable nitrogen and carbon isotope values, variations in DP concentrations in the gull species studied are explained by foraging behavior and diet rather than by the trophic position. Both DP stereoisomers were quantified in all the samples studied, and a slight enrichment of the anti-DP could have occurred in both species. The quantification of anti-[DP-1Cl] only in ∼58 % of yellow-legged gulls support the hypothesis of a species-dependent factor influencing the bioaccumulation and/or biotransformation of Dechlorane-related compounds. This study reports on the first measurements of Dechlorane-related compounds in biota from the North African continent, contributing to the knowledge about DP environmental fate and distribution. In the light of our results, more research on differences in species-dependent bioaccumulation and biotransformation capabilities as well as ecological effects is encouraged in future Dechlorane-related compound studies.

  6. Persistent Organic Pollutants in gull eggs of two species (Larus michahellis and Larus audouinii) from the Ebro delta Natural Park.

    PubMed

    Morales, Laura; Martrat, Maria Generosa; Olmos, Jorge; Parera, Jordi; Vicente, Joana; Bertolero, Albert; Abalos, Manuela; Lacorte, Silvia; Santos, Francisco Javier; Abad, Esteban

    2012-09-01

    The aim of this study was to determine the impact of priority and emerging Persistent Organic Pollutants (POPs) in gull eggs from two species, the scavenger Larus michahellis and the protected species, Larus audouinii. These two species share habitat in the Natural Park of the Ebro delta (Catalonia, Spain). Compounds studied are included or under consideration in the Stockholm Convention and comprise polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated compounds (OCs), perfluorinated compounds (PFCs) and short chain chlorinated paraffins (SCCPs). Four methods based in selective extraction and gas or liquid chromatography coupled to mass spectrometry were used and quality parameters are provided. OC pesticides and marker PCBs were the most abundant chemical families detected in eggs from the two species, followed by PFCs, PBDEs (especially BDE 209) and SCCPs. Dioxin-like PCBs and PCDD/Fs were also detected in all samples. The overall widespread presence of POPs is discussed in terms of feeding habits, bird ecology and anthropogenic pressures in the protected Ebro delta breeding area. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Introduction of the air cushion vehicle 'Larus' to the North American market

    NASA Astrophysics Data System (ADS)

    Makinen, E.; Wainwright, J.

    The 'Larus' ACV, which currently operates as a ferry in the Northern Baltic with a payload of 25 tonnes and 46 passengers, will be refurbished for operations in the Canadian Arctic. These modifications will encompass the incorporation of an Arctic-grade rubber skirt, additional fire and thermal insulation, more heating and washrooms for passenger compartments, a fire extinghuishing system, a second radar unit, and satellite navigation. A development history and performance evaluation of the Larus are given.

  8. Reduced oxygen diffusion across the shell of Gray gull (Larus modestus) eggs.

    PubMed

    Monge, C C; Ostojic, H; Aguilar, R; Cifuentes, V

    2000-01-01

    Gray gulls, Larus modestus, nest 1500 m above sea level in northern Chile's Atacama Desert, one of the driest in the world. Their eggshell gas permeability, one third of that found in other Larus species, is an adaptation that reduces water loss, but at the expense of oxygen diffusion into the air cell with resultant hypoxia and reduced metabolic rate. This contrasts with characteristics found in birds nesting at very high altitudes where oxygen diffusion across the egg shell is maximized at the expense of water conservation. The oxygen consumption (MO2) of Larus modestus is 66% that of Larus argentatus; the oxygen conductance (GO2) is equivalent to 48% of that obtained in 5 other bird species. The oxygen partial pressure (PAO2) in the air chamber of Larus modestus (84 Torr) is lower than that of 10 other bird species whose average (PAO2) is 106 Torr. The CO2 partial pressure (PACO2) in the air chamber of Larus modestus is 68 Torr, a higher value than that found in 9 other bird species whose average (PACO2) is 39 Torr.

  9. Probable epizootic chlamydiosis in wild California (Larus californicus) and ring-billed (Larus delawarensis) gulls in North Dakota

    USGS Publications Warehouse

    Franson, J.C.; Pearson, J.E.

    1995-01-01

    During the summer of 1986, more than 400 California gulls (Larus californicus) and ring-billed gulls (Larvus delawarensis), primarily fledglings, died on an island in Lake Sakakawea near New Town, North Dakota (USA). Mortality was attributed largely to chlamydiosis. Necropsy findings in nine carcasses included splenomegaly (n = 9), hepatomegaly (n = 4), and pericarditis (n = 1). Livers from three California gulls and two ring-billed gulls, and spleens from the same five birds plus a third ring-billed gull were positive for Chlamydia psittaci by the direct immunofluorescence test. Chlamydia psittaci was isolated from separate pools of liver and spleen from one California gull and one ring-billed gull. This is believed to be the first record of epizootic chlamydiosis in gulls and the second report of epizootic chlamydial mortality in wild birds in North America.

  10. First record of laughing gull (Larus atricilla) in French Polynesia

    USGS Publications Warehouse

    Vanderwerf, Eric A.; Pierce, Ray J.; Tibbitts, T.L.; Salducci, J.-M.; Gill, V.A.; Wragg, Graham

    2004-01-01

    On 6 March 2003 at 0800 h and again at 1300 h, while preparing for biological surveys in the Tuamotu and Gambier archipelagos of French Polynesia, we observed an immature gull flying in Rikitea harbor on Mangareva in the Gambier Islands. On both occasions we observed the gull for several minutes at distances as close as 20 m while it flew around the waterfront. It was a medium-sized gull, with long, pointed wings. The head was white with dark streaks and smudging on the nape. The bill was dark and of moderate length and thickness. The back and inner secondaries were dark grey, and the outer secondaries and primaries were a mottled dusky grey-brown. There was a complete, broad, dark band across the tip of the tail. These characters, particularly the long, pointed wings and broad tail band, led us to conclude that the bird was a laughing gull (Larus atricilla) in first winter plumage. Franklin’s gull (L. pipixcan) is similar in appearance and has been reported previously in several Pacific island groups (King 1967; Pratt et al. 1987), but can be distinguished from L. atricilla by its slightly smaller size, smaller bill, and narrower, incomplete tail band (Sibley 2000).

  11. Fidelity and persistence of Ring-billed (Larus delawarensis) and Herring (Larus argentatus) gulls to wintering sites

    USGS Publications Warehouse

    Clark, Daniel E.; Koenen, Kiana K. G.; Whitney, Jillian J.; MacKenzie, Kenneth G.; Destefano, Stephen

    2016-01-01

    While the breeding ecology of gulls (Laridae) has been well studied, their movements and spatial organization during the non-breeding season is poorly understood. The seasonal movements, winter-site fidelity, and site persistence of Ring-billed (Larus delawarensis) and Herring (L. argentatus) gulls to wintering areas were studied from 2008–2012. Satellite transmitters were deployed on Ring-billed Gulls (n = 21) and Herring Gulls (n = 14). Ten Ring-billed and six Herring gulls were tracked over multiple winters and > 300 wing-tagged Ring-billed Gulls were followed to determine winter-site fidelity and persistence. Home range overlap for individuals between years ranged between 0–1.0 (95% minimum convex polygon) and 0.31–0.79 (kernel utilization distributions). Ringbilled and Herring gulls remained at local wintering sites during the non-breeding season from 20–167 days and 74–161 days, respectively. The probability of a tagged Ring-billed Gull returning to the same site in subsequent winters was high; conversely, there was a low probability of a Ring-billed Gull returning to a different site. Ring-billed and Herring gulls exhibited high winter-site fidelity, but exhibited variable site persistence during the winter season, leading to a high probability of encountering the same individuals in subsequent winters.

  12. High-Resolution Chirp and Mini-Sparker Seismic-Reflection Data From the Southern California Continental Shelf - Gaviota to Mugu Canyon

    USGS Publications Warehouse

    Sliter, Ray W.; Triezenberg, Peter J.; Hart, Patrick E.; Draut, Amy E.; Normark, William R.; Conrad, James E.

    2008-01-01

    The U.S. Geological Survey (USGS) collected high-resolution shallow seismic-reflection data in September, 2007, and June-July, 2008, from the continental shelf offshore of southern California between Gaviota and Mugu Canyon, in support of the California's State Waters Mapping Program. Data were acquired using SIG 2mille mini-sparker and Edgetech chirp 512 instruments aboard the R/V Zephyr (Sept. 2007) and R/V Parke Snavely (June-July 2008). The survey area spanned approximately 120 km of coastline, and included shore-perpendicular transects spaced 1.0-1.5 km apart that extended offshore to at least the 3-mile limit of State waters, in water depths ranging from 10 m near shore to 300 m near the offshore extent of Mugu and Hueneme submarine canyons. Subbottom acoustic penetration spanned tens to several hundred meters, variable by location. This report includes maps of the surveyed transects, linked to Google Earth software, as well as digital data files showing images of each transect in SEG-Y, JPEG, and TIFF formats. The images of sediment deposits, tectonic structure, and natural-gas seeps collected during this study provide geologic information that is essential to coastal zone and resource management at Federal, State and local levels, as well as to future research on the sedimentary, tectonic, and climatic record of southern California.

  13. Community structure of lice (Insecta: Phthiraptera) from two sympatric gull species: kelp gull (Larus dominicanus) and Franklin's gull (Larus pipixcan) in Talcahuano, Chile.

    PubMed

    González-Acuña, D; Corvalan, F; Barrientos, C; Doussang, D; Mathieu, C; Nilsson, L; Casanueva, M E; Palma, R L

    2011-01-01

    A total of 1,177 lice of four species were collected from 124 kelp gulls (Larus dominicanus) and 137 lice of the same four species from 60 Franklin's gulls (Larus pipixcan). The louse Saemundssonia lari (O Fabricius) (Phthiraptera: Philopteridae) was the most numerous on both gull species, with infestation rates of 4.9 on kelp gulls and 1.8 on Franklin's gulls. The second most abundant louse was Quadraceps punctatus (Burmeister), with a high infestation rate but low prevalence on kelp gulls; those parameters were much lower among lice from Franklin's gulls. The composition and community structure of the lice were similar on both host species, but not their infestation rates. In addition, the feather mite Zachvatkinia larica Mironov (Acari: Avenzoariidae) is recorded from kelp gulls and Franklin's gulls for the first time, while the gamasid mite Larinyssus sp. is recorded from kelp gulls, also for the first time. The population parameters of all species of ectoparasites are discussed.

  14. Genetic affinities within the herring gull Larus argentatus assemblage revealed by AFLP genotyping.

    PubMed

    de Knijff P; Denkers, F; van Swelm, N D; Kuiper, M

    2001-01-01

    To date, the taxonomic status of circumpolar breeding populations of the Herring Gull Larus argentatus, the Lesser Black-backed Gull Larus fuscus, and the closely related Yellow-legged Gull Larus cachinnans has been based on differences or similarities in phenotype, morphology, and feeding and premating behavior. To shed some new light on the many taxonomic uncertainties surrounding these taxa, we describe the results of a large DNA study based on comparing the distribution of 209 biallelic markers among 109 gulls, representing 11 gull taxa of the Herring Gull assemblage and the Common Gull Larus canus. A detailed phylogenetic analysis failed to show clustering of individuals into groups representing either geographic origin or phenotype. Alternatively, birds were grouped into taxa defined on the basis of phenotype and geographic origin or phenotype alone. Genetic analyses revealed significantly different genetic distances between all pairs of taxa. However, based on these genetic distances, again no consistent phylogenetic tree could be constructed. Analysis of molecular variance indicated that about 77% of the total genetic variability among these gulls could be explained by within-taxon differences. Only 23% of the total genetic variability was due to genetic differences between taxa, irrespective of their species or subspecies status. Although this seems to challenge the current taxonomic treatment of the herring gull assemblage, our results are too premature and too incomplete to recommend a drastic change.

  15. [Paramonostomum antarcticum (Trematoda, Notocotylidae) in Larus dominicanus from South Shetlands (Antarctica)].

    PubMed

    Odening, K

    1982-08-01

    Paramonostomum antarcticum Graefe, 1968 from the rectum of blackbacked gull from King George as Island (South Shetlands, Antarctica) is described. As a result of that Larus dominicanus is presented the new host of this trematode. The morphology is compared with the original description of P. signiense Jones & Williams, 1969. The relations between the two possibly identical Antarctic species are discussed. It is proposed to invalidate the subgenus Paramonostomoides Yamaguti, 1971.

  16. Contaminant levels in Herring (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs from colonies in the New York harbor complex between 2012 and 2013.

    PubMed

    Burger, Joanna; Elbin, Susan

    2015-03-01

    Birds living in coastal areas are exposed to severe storms and tidal flooding during the nesting season, but also to contaminants that move up the food chain from the water column and sediment to their prey items. We examine metals in Herring Gull (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs collected from the New York/New Jersey harbor estuary in 2012 and in 2013 to determine if there were significant yearly differences in metal levels. We test the null hypothesis that there were no significant yearly differences in metal levels. We investigate whether there were consistent differences in metals from 2012 to 2013 that might suggest a storm-related effect because Superstorm Sandy landed in New Jersey in October 2012 with high winds and extensive flooding, and view this research as exploratory. Except for arsenic, there were significant inter-year variations in the mean levels for all colonies combined for Herring Gull, and for lead, mercury and selenium for Great Black-backed Gulls. All metal levels in 2013 were less than in 2012, except for lead. These differences were present for individual colonies as well. Metal levels varied significantly among islands for Herring Gulls in both years (except for cadmium in 2013). No one colony had the highest levels of all metals for Herring Gulls. A long term data set on mercury levels in Herring Gulls indicated that the differences between 2012 and 2013 were greater than usual. Several different factors could account for these differences, and these are discussed.

  17. Contaminant levels in Herring (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs from colonies in the New York harbor complex between 2012 and 2013

    PubMed Central

    Elbin, Susan

    2014-01-01

    Birds living in coastal areas are exposed to severe storms and tidal flooding during the nesting season, but also to contaminants that move up the food chain from the water column and sediment to their prey items. We examine metals in Herring Gull (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs collected from the New York/New Jersey harbor estuary in 2012 and in 2013 to determine if there were significant yearly differences in metal levels. We test the null hypothesis that there were no significant yearly differences in metal levels. We investigate whether there were consistent differences in metals from 2012 to 2013 that might suggest a storm-related effect because Superstorm Sandy landed in New Jersey in October 2012 with high winds and extensive flooding, and view this research as exploratory. Except for arsenic, there were significant inter-year variations in the mean levels for all colonies combined for Herring Gull, and for lead, mercury and selenium for Great Black-backed Gulls. All metal levels in 2013 were less than in 2012, except for lead. These differences were present for individual colonies as well. Metal levels varied significantly among islands for Herring Gulls in both years (except for cadmium in 2013). No one colony had the highest levels of all metals for Herring Gulls. A long term data set on mercury levels in Herring Gulls indicated that the differences between 2012 and 2013 were greater than usual. Several different factors could account for these differences, and these are discussed. PMID:25471353

  18. Malignant melanoma in a seagull (Larus fuscus): morphological and immunohistochemical approach.

    PubMed

    Costagliola, Alessandro; Britti, Domenico; Russo, Valeria; Meomartino, Leonardo; Castagna, Fabio; Giordano, Debora; Insabato, Luigi; Paciello, Orlando

    2011-03-01

    A common seagull (Larus fuscus) was found near the southern coast of Italy by the veterinarians of the local wild animal rescue center. Physical examination of the bird revealed an ulcerated mass involving a majority of the oral cavity; the mass did not allow for normal feeding. After the bird died necropsy was performed and the mass was histologically and immunohistochemically examined. The morphology and the immunoreactivity for Melan-A and S-100 antigens led to a diagnosis of malignant melanoma. This is the first case of malignant melanoma described in a seagull, and herein we compare the characteristics of the present case with malignant melanoma already described in domestic animals.

  19. Vigilance and feeding behaviour in large feeding flocks of laughing gulls, Larus atricilla, on Delaware Bay

    NASA Astrophysics Data System (ADS)

    Burger, Joanna; Gochfeld, Michael

    1991-02-01

    Laughing gulls ( Larus atricilla) forage on horseshoe crab ( Limulus polyphemus) eggs during May in Delaware Bay each year. They feed in dense flocks, and foraging rates vary with vigilance, bird density, number of steps and location in the flock, whereas time devoted to vigilance is explained by number of steps, density, location and feeding rates. The time devoted to vigilance decreases with increasing density, increasing foraging rates and decreasing aggression. Birds foraging on the edge of flocks take fewer pecks and more steps, and devote more time to vigilance than those in the intermediate or central parts of a flock.

  20. Campylobacter volucris sp. nov., isolated from black-headed gulls (Larus ridibundus).

    PubMed

    Debruyne, Lies; Broman, Tina; Bergström, Sven; Olsen, Björn; On, Stephen L W; Vandamme, Peter

    2010-08-01

    During a study of the prevalence of Campylobacter jejuni in black-headed gulls (Larus ridibundus) in Sweden, three isolates, strains LMG 24379, LMG 24380T and LMG 24381, were initially identified as Campylobacter lari. Further characterization by both AFLP and whole-cell protein SDS-PAGE analyses revealed that they formed a distinct group in the genus Campylobacter. This unique position was confirmed by phenotypic characterization, 16S rRNA and hsp60 gene sequence analysis and DNA-DNA hybridizations. The combined data confirm that these isolates represent a novel species within the genus Campylobacter, for which the name Campylobacter volucris sp. nov. is proposed. The type strain is LMG 24380T (=CCUG 57498T).

  1. Plastic consumption and diet of Glaucous-winged Gulls (Larus glaucescens).

    PubMed

    Lindborg, Valerie A; Ledbetter, Julia F; Walat, Jean M; Moffett, Cinamon

    2012-11-01

    We analyzed dietary habits and presence of plastic in 589 boluses of Glaucous-winged Gulls (Larus glaucescens) as one of two studies on the impact of plastics on marine life in the US Salish Sea. Volunteers dissected boluses collected (2007-2010) from Protection Island, Washington. Components were separated into 23 food and non-food categories. Plastic was found in 12.2% of boluses, with plastic film being the most common plastic form. No diet specialization was observed. Vegetation was the most abundant component, found in 91.3% of boluses. No relationship was observed between any dietary items and occurrence or type of plastic found. Load and potential ecological impact in the marine environment can be expected to increase concurrently with increasing plastic use and number and variety of plastic sources. Future studies are necessary to understand the impacts of plastic ingestion on this species. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Organochlorines and heavy metals in Herring Gull (Larus argentatus) eggs and chicks from the same clutch

    SciTech Connect

    Becker, P.H. ); Sperveslage, H. )

    1989-05-01

    In an earlier paper the authors investigated the intraclutch variability in levels of toxic pollutants and compared this contamination with that of the female Herring Gull (Larus argentatus) after production of the clutch in question. In the present study, they examine the concentrations of contaminants in chicks as compared with one egg of the same clutch. Such studies are important with regard to the question as to which ontogenetic stage is most endangered by toxic pollutants. Some investigations concerning this problem have already been carried out, but they don't refer to samples taken from the same clutches. Chicks receive contaminants mainly from two sources: from the egg, which reflects directly the contamination of the breeding female as well as from the food. Moreover the concentrations of pollutants in chicks vary with growth-dependent body distribution and with a decline of the lipid content.

  3. Enteric infections by trematodes and nematodes in Olrog's gull, Larus atlanticus.

    PubMed

    La Sala, Luciano F; Smits, Judit E; Martorelli, Sergio R

    2012-12-01

    Trematodes and nematodes can be pathogenic helminths of birds. Every year during the breeding season, there is variable mortality among chicks from the largest Olrog's gull (Larus atlanticus) colony in Argentina. During two consecutive breeding seasons of Olrog's gull, we studied epidemiological and pathological aspects of infections by digeneans (Microphallidae) and nematodes (Acuariidae) in Olrog's gull chicks. Prevalence of nematode infection was 80.3% in 2005 and 89.2% in 2006, and mean intensity was 23.7 in 2005 and 50.8 in 2006. The risk for infection rose 34.3% and the intensity of infection 6.7% for every increase of 1 mm in head-beak length. The nematodes occupied the proventricular glands and caused disruption of their structure and mild inflammatory proventriculitis. Prevalence of digenean infection was 97.0% in 2005 and 97.3% in 2006. In 10-day-old live chicks, prevalence was 98.0% in 2006 and 95.3% in 2007. Infection was associated with severe catarrhal enteritis, lymphocyte/eosinophil-rich inflammatory responses, extensive fibroblast proliferation around the parasites, and disruption of the architecture of the adjacent crypts.

  4. Effects of Invasive European Fire Ants (Myrmica rubra) on Herring Gull (Larus argentatus) Reproduction

    PubMed Central

    DeFisher, Luke E.; Bonter, David N.

    2013-01-01

    Various invasive ant species have negatively affected reproductive success in birds by disrupting nest site selection, incubation patterns, food supply, and by direct predation on nestlings. Impacts can be particularly severe when non-native ants colonize seabird nesting islands where thousands of birds may nest in high densities on the ground or in burrows or crevices. Here we report on the first documented effects of Myrmica rubra, the European fire ant, on the reproduction of birds in its non-native range. We documented herring gulls (Larus argentatus) on Appledore Island, Maine, engaging in more erratic incubation behaviors at nests infested by the ants. Newly-hatched chicks in some nests were swarmed by ants, leading to rapid chick death. Due to high overall rates of chick mortality, survival probabilities did not vary between nests with and without ant activity, however chick growth rates were slower at nests with ants than at ant-free nests. Ant infestation likely leads to longer-term fitness consequences because slower growth rates early in life may ultimately lead to lower post-fledging survival probabilities. PMID:23691168

  5. Heavy metal concentrations in Black-tailed Gull (Larus crassirostris) chicks, Korea.

    PubMed

    Kim, Jungsoo; Oh, Jon-Min

    2014-10-01

    The objectives of this study were to quantify concentrations of heavy metals in livers and stomach contents of Black-tailed Gull (Larus crassirostris) chicks from two islands in Korea. Iron and manganese concentrations were significantly higher in chick livers at Hongdo Island compared to Rando Islnad. In contrast, zinc, copper and cadmium concentrations were significantly higher at Rando Island than Hongdo Island. On Hongdo Island, Black-tailed Gull chicks at a lighthouse site had higher lead concentrations in livers and stomach contents than at a nearby reference site and stomach contents of Black-tailed Gull chicks had significantly higher lead concentrations than regurgitated diets. In Hongdo Island, manganese, lead and cadmium concentrations were significantly correlated between livers and stomach contents. Essential elements such as iron, zinc, manganese and copper concentrations from the present study were within the range reported for other seabird species including gulls. Livers of four individual gull chicks (13.3%) were at a level considered lead exposed (6-30 μg g(-1) dry weight), but cadmium concentrations in all specimens were within the background level (<3 μg g(-1) dry weight) for wild birds. Elevated lead concentrations on lighthouse site may be attributed to ingestion of paint chips and these concentrations may negatively affect chick behavior, growth and survival.

  6. Interseasonal variation in blood concentrations of organochlorines in great black-backed gulls (Larus marinus).

    PubMed

    Bustnes, Jan Ove; Skaare, Janneche Utne; Berg, Vidar; Tveraa, Torkild

    2005-07-01

    In two subsequent breeding seasons (2001 and 2002), we measured 12 organochlorines (OCs), including hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), p,p'-dichlorodiphenyldichloroethylene (DDE), oxychlordane, and eight polychlorinated biphenyl congeners (PCBs), in the blood of the same 25 great black-backed gulls (Larus marinus). The wet-weight concentrations of different OCs in the blood decreased between 45 and 60% from 2001 to 2002. The main reasons for this were lower blood-lipid concentrations and higher body condition in 2002 compared to 2001. The differences in blood lipids and body condition probably resulted from changes in the availability of different prey types between the years. Despite the variation in the blood concentrations of OCs, there was a high predictability of the relative relationship among individuals between the years, especially for the most-persistent compounds (persistent PCBs, oxychlordane, and DDE); that is, individuals with high levels in 2001 still had relatively high levels compared to other individuals in 2002. This suggests that a concentration obtained from a single blood sample is a relatively reliable measurement of OC burdens for individual great black-backed gulls compared to other individuals, independent of changes in mean OC levels within the population. However, by including information about the nutritional status of individuals, more precise interference from samples in different years and locations may be made. Moreover, the great seasonal variation in OC levels within individuals may have implications for how OC monitoring should be conducted in gull populations.

  7. An outbreak of type C botulism in Herring Gulls (Larus argentatus) in Southeastern Sweden

    USGS Publications Warehouse

    Neimanis, A.; Gavier-Widen, D.; Leighton, F.; Bollinger, T.; Rocke, T.; Morner, T.

    2007-01-01

    From 2000 to 2004, over 10,000 seabirds, primarily Herring Gulls (Larus argentatus), died from an undetermined cause in the Blekinge archipelago in southeastern Sweden. In June 2004, 24 affected Herring Gulls were examined clinically, killed humanely, and 23 were examined by necropsy. Seven and 10 unaffected Herring Gulls collected from a local landfill site and from Iceland, respectively, served as controls. All affected birds showed similar neurologic signs, ranging from mild incoordination and weakness to severe flaccid paralysis of legs and wings, but generally were alert and responsive. All affected gulls were in normal nutritional condition, but were dehydrated and had empty stomachs. No gross or microscopic lesions, and no bacterial or viral pathogens were identified. Type C botulinum toxin was detected in the sera of 11 of 16 (69%) affected gulls by mouse inoculation. Type C botulism was the proximate cause of disease in 2004. Sera from 31% of birds tested from outbreaks in 2000 to 2003 also had detectable type C botulinum toxin by mouse inoculation. No large-scale botulism outbreak has been documented previously in this area. The source of toxin, initiating conditions, and thus, the ultimate cause of this outbreak are not known. This epidemic might signal environmental change in the Baltic Sea. ?? Wildlife Disease Association 2007.

  8. Seasonal movements and migration of Pallas's Gulls Larus ichthyaetus from Qinghai Lake, China

    USGS Publications Warehouse

    Muzaffar, S.B.; Takekawa, J.Y.; Prosser, D.J.; Douglas, D.C.; Yan, B.; Xing, Z.; Hou, Y.; Palm, E.C.; Newman, S.H.

    2008-01-01

    We studied the seasonal movements and migration often Pallas's Gulls Larus ichthyaetus trom Qinghai Lake to assess migratory routes and stopover areas. Each individual was captured and equipped with an 18 g solar-powered Platform Transmitter Terminal (PIT) to track its movements from September 2007 to May 2008. Six individuals remained near Qinghai Lake until the PTTs stopped transmitting. Three individuals flew 50-330 km from Qinghai Lake to nearby salt lakes. One individual departed on 8 December and flew over 1,700 km south-west to arrive at coastal Bangladesh on 9 January 2008. Two individuals flew in October to the Brahmaputra River in Assam, India, remaining in the area for at least one month until one stopped transmitting. The second individual travelled southwest to coastal Bangladesh. Of the two individuals overwintering in Bangladesh, one remained for 67 days before migrating north. The second bird departed after 96 days, and it returned to Qinghai on 10 May 2008 after 48 days in migration. Both individuals that overwintered in coastal Bangladesh arrived much later than the outbreaks of Highly Pathogenic Avian Influenza (HP AI H5N I) in poultry in 2007. This disparity in timing would tentatively suggest that this species was not involved in long-distance movements of the virus. Instead, the converse may be true: previous work demonstrates the potential for virus spill-over trom poultry into gulls and other wild bird species upon arrival into locations with widespread HPAI H5NI outbreaks and environmental contamination.

  9. Macroanatomic, light, and electron microscopic examination of pecten oculi in the seagull (Larus canus).

    PubMed

    Ince, Nazan Gezer; Onuk, Burcu; Kabak, Yonca Betil; Alan, Aydin; Kabak, Murat

    2017-07-01

    The present study was conducted to determine macroanatomic characteristic as well as light and electron microscopic examination (SEM) of pecten oculi and totally 20 bulbus oculi belonging to 10 seagulls (Larus canus) were used. Pecten oculi formations consisted of 18 to 21 pleats and their shape looked like a snail. Apical length of the pleats forming pecten oculi were averagely measured as 5.77 ± 0.56 mm, retina-dependent base length was 9.01 ± 1.35 mm and height was measured as 6.4 ± 0.62 mm. In pecten oculi formations which extend up to 1/3 of the bulbus oculi, two different vascular formations were determined according to thickness of the vessel diameter. Among these, vessels with larger diameters which are less than the others in count were classified as afferent and efferent vessels, smaller vessels which are greater in size were classified as capillaries. Furthermore, the granules which were observed intensely in apical side of the pleats of pecten oculi were observed to distribute randomly along the plica. © 2017 Wiley Periodicals, Inc.

  10. Hybridization among Arctic white-headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Chesser, R. Terry; Bell, Douglas A.; Dove, Carla J.

    2012-01-01

    We studied the influence of glacial oscillations on the genetic structure of seven species of white-headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice-free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (FST= 0.129), introns (ΦST= 0.185), and mtDNA control region (ΦST= 0.461), with among-group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among-group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger t estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white-headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species-specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white-headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed.

  11. Perfluorinated, brominated, and chlorinated contaminants in a population of lesser black-backed gulls (Larus fuscus).

    PubMed

    Bustnes, Jan O; Borgå, Katrine; Erikstad, Kjell E; Lorentsen, Svein-Håkon; Herzke, Dorte

    2008-06-01

    Protein-bound perfluorinated compounds (PFCs) and lipid-soluble polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) were measured in whole blood from a large number (n = 83) of breeding lesser black-backed gulls (Larus fuscus) caught during two distinct sampling periods in a colony on the coast of northern Norway. We analyzed 14 PFCs (seven were detected in more than 75% of samples), 10 PBDEs (only BDE 47 was detected), and 27 OCs, including 12 polychlorinated biphenyl (PCB) congeners (14 OCs were detected). Median total PFC concentration was higher than median total OC concentration (43 vs 39 ng/g wet wt). Perfluorooctane sulfonate (PFOS) was the dominant PFC (mean relative contribution of PFOS to total contaminant concentration in blood [Sigmatotal contaminants] was 38%), whereas total PCB (26% of Sigmatotal contaminants) and p,p'-DDE (2,2-bis(4-chlorophenyl)-1,1-dichloroethene; 13% of Sigmatotal contaminants) were the dominant OCs. No covariability was found between protein-bound and lipid-soluble compounds; individuals with high concentrations of PFCs did not have high concentrations of OCs or BDE 47. The concentrations of PFCs were lower in birds caught during the late sampling period compared to those of the early period, and females had lower levels of some PFCs compared with males, suggesting that females sequester fluorinated substances into eggs. For lipid-soluble compounds, no significant sex or sampling period differences were found, except that trans-nonachlor, cis-nonachlor, and p,p'-DDE concentrations were lower in birds caught during the late sampling period. The pattern of PFC compounds (relative to PFOS) and lipid-soluble compounds (relative to PCB 153) differed between sampling periods in females but not in males. Finally, PFCs were distributed more uniformly within the population than the lipid-soluble compounds, for which the distributions were strongly negatively skewed.

  12. Trace element contamination in nestling black-tailed gulls (Larus crassirostris) in Korea.

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2015-05-01

    At Hongdo Island, Gyeongsangnam-do, Korea, a breeding site of black-tailed gull (Larus crassirostris), we collected nestlings from two locations: a "reference" site (n = 10) with no known source of lead contamination and "lighthouse" site (n = 10) with suspected lead contamination from leaded paint. Iron concentrations in the kidney and bone, manganese in the muscle, copper in the bone, lead in the muscle and bone, and cadmium in the liver, muscle, and bone at the reference site were significantly higher than at the lighthouse. Manganese concentrations in the liver and kidney, and lead in the kidney were significantly greater at the lighthouse than at the reference site. Iron, zinc, manganese, copper, lead and cadmium concentrations had tissue-specific accumulation at both sites. Lead concentrations in 10 % of livers and in 80 % of kidneys at the lighthouse, and in 20 % of livers from the reference were within a range considered toxic (>6.00 μg/g dw in the liver and kidney). Lead concentrations in 50 % of black-tailed gull nestlings at the reference and 80 % nestlings at the lighthouse were greater in livers than in bones, which is suggestive of acute lead exposure. For cadmium, all liver and kidney concentrations from two sites were at a level considered background in birds. Cadmium concentrations of every sample were higher in kidneys than in livers, suggestive of chronic cadmium exposure. Lead concentrations in gull nestlings in the present study were relatively higher than other gull species worldwide, but cadmium concentrations were relatively lower.

  13. Effects of organochlorine contaminants on thyroid hormone levels in Arctic breeding glaucous gulls, Larus hyperboreus.

    PubMed Central

    Verreault, Jonathan; Skaare, Janneche Utne; Jenssen, Bjørn Munro; Gabrielsen, Geir Wing

    2004-01-01

    Studies on glaucous gulls (Larus hyperboreus) breeding in the Barents Sea have reported that high blood levels of halogenated organic contaminants in this species might cause reproductive, behavioral, and developmental stress. However, potential endocrine system modulation caused by contaminant exposure has yet not been reported in this Arctic apical predator. In this present study we aimed to investigate whether the current levels of a selection of organochlorines (OCs) were associated with altered circulating levels of thyroid hormones (THs) in free-ranging adult glaucous gulls breeding at Bear Island in the Barents Sea. Blood concentrations of 14 polychlorinated biphenyls, hexachlorobenzene (HCB), oxychlordane, and p,p' -dichlorodiphenyldichloroethylene (p,p' -DDE) were quantified, in addition to free and total thyroxine (T4) and triiodothyronine (T3), in plasma of 66 glaucous gulls in the spring of 2001. Negative correlations were found between plasma levels of T4 and T4:T3 ratio, and blood levels of OCs in male glaucous gulls. Despite their relatively low contribution to the total OC fraction, HCB and oxychlordane were the most prominent compounds in terms of their negative effect on the variation of the T4:T3 ratio. Moreover, lower T4 levels and T4:T3 ratios were measured in glaucous gulls breeding in a colony exposed to high levels of OCs, compared with a less exposed colony. Levels of T3 were elevated in the high-OC-exposed colony. This may indicate that the glaucous gull is susceptible to changes to TH homeostasis mediated by exposure to halogenated organic contaminants. PMID:15064156

  14. Hybridization among Arctic white-headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene

    PubMed Central

    Sonsthagen, Sarah A; Chesser, R Terry; Bell, Douglas A; Dove, Carla J

    2012-01-01

    We studied the influence of glacial oscillations on the genetic structure of seven species of white-headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice-free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (FST= 0.129), introns (ΦST= 0.185), and mtDNA control region (ΦST= 0.461), with among-group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among-group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger τ estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white-headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species-specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white-headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed. PMID:22833800

  15. Comparisons of host specificity in feather louse genera (Insecta: Phthiraptera: Philopteridae) parasitizing gulls (Aves: Laridae: Larus).

    PubMed

    Yamagishi, Ayaka; Yao, Izumi; Johnson, Kevin P; Yoshizawa, Kazunori

    2014-06-01

    Data from gene sequences and morphological structures were collected for the gull feather lice, Saemundssonia lari, Quadraceps punctatus, and Q. ornatus, parasitizing Larus crassirostris and L. schistisagus. Saemundssonia lari was collected from both gull species, and no detectable morphological and genetic differences were found between lice collected from the two different hosts. In contrast, Q. punctatus was only collected from L. crassirostris, whereas Q. ornatus was only collected from L. schistisagus. The two Quadraceps species were genetically highly divergent, and body-size differences corresponding to the gull's body size (Harrison's rule) were also detected between them. Both Quadraceps species were collected from the interbarb of the remex or rectrix, and a match in body size between the louse and the interbarb space may be important in escape from host preening defenses. In contrast, Saemundssonia is a head louse, inhabiting the finer feathers of the head and neck, which the bird cannot preen. A close match to host body size may be less important for lice in the head microhabitat. The differences in the pattern of host-specificity between Saemundssonia and Quadraceps on the two focal host species of this study were probably due to their different microhabitat preferences. More broadly, comparisons of the gene sequences of S. lari and Q. punctatus to those from other gull hosts showed that genetically almost undifferentiated populations of both species were distributed on wide range of gull species. Frequent interspecific hybridization of gulls is one possible factor that may allow these lice to maintain gene flow across multiple host species.

  16. Food availability and nest predation influence life history traits in Audouin's gull, Larus audouinii.

    PubMed

    Oro, Daniel; Pradel, Roger; Lebreton, Jean-Dominique

    1999-03-01

    The effects of food availability and nest predation on several life history traits such as adult survival, dispersal, and reproductive performance were assessed in an Audouin's gull (Larus audouinii) colony during the period 1992-1997. The amounts of fish discarded from trawlers were used as a measure of food availability, and a trawling moratorium which partially overlapped with the breeding season of the gulls was taken into account. The effects of nest predation were assessed in 1994, when a terrestrial predator entered the colony and remained for the whole breeding season preying on both eggs and chicks. Using the moratorium and the predatory event as natural experiments, several hypotheses were tested: (a) food supply would affect breeding performance but not adult survival (independently of age and sex), since gulls are long-lived and adult survival is the most sensitive demographic parameter in their population dynamics; (b) the predator would trigger breeding dispersal (although gulls are mostly philopatric, they are known to abandon their natal colony after breeding failure instigated by events such as this). If breeding dispersal occurs, the rate is expected to be higher in females than in males, and higher in new breeders than in more experienced breeding birds, as is usually recorded in colonial seabirds. Probabilities of resighting and survival were estimated separately, using capture-recapture models. As expected, changes in food availability did not affect adult survival, whereas they influenced egg volume, clutch size, and breeding success. Local adult survival was estimated to be 0.908 (SD = 0.007) for males and females, and it did not change significantly with the age of individuals (range 3-8 years). The predator significantly decreased breeding success, and caused the dispersal of a number of adults probably to breed in another colony; this rate was estimated at an average of 0.10 (SD = 0.02). As expected, inexperienced breeders

  17. Characterization of AhR agonists reveals antagonistic activity in European herring gull (Larus argentatus) eggs.

    PubMed

    Muusse, Martine; Christensen, Guttorm; Gomes, Tânia; Kočan, Anton; Langford, Katherine; Tollefsen, Knut Erik; Vaňková, Lenka; Thomas, Kevin V

    2015-05-01

    European herring gull (Larus argentatus) eggs from two Norwegian islands, Musvær in the south east and Reiaren in Northern Norway, were screened for dioxins, furans, and dioxin-like and selected non-dioxin-like polychlorinated biphenyls (PCBs), and subjected to non-target analysis to try to identify the aryl hydrocarbon receptor (AhR) agonists, responsible for elevated levels measured using the dioxin responsive chemically activated luciferase expression (DR-CALUX) assay. Eggs from Musvær contained chemically calculated toxic equivalent (WHO TEQ) levels of between 109 and 483 pg TEQ/g lw, and between 82 and 337 pg TEQ/g lw was determined in eggs from Reiaren. In particular PCB126 contributed highly to the total TEQ (69-82%). In 19 of the 23 samples the calculated WHO TEQ was higher than the TEQCALUX. Using CALUX specific relative effect potencies (REPs), the levels were lower at between 77 and 292 pg/g lw in eggs from Musvær and between 55 and 223 pg/g lw in eggs from Reiaren, which was higher than the TEQCALUX in 16 of the 23 samples. However, the means of the REP values and the TEQCALUX were not significantly different. This suggests the presence of compounds that can elicit antagonist effects, with a low binding affinity to the AhR. Non-target analysis identified the presence of hexachlorobenzene (HCB) (quantified at 9.6-185 pg/g lw) but neither this compound nor high concentrations of PCB126 and non-dioxin-like PCBs could explain the differences between the calculated TEQ or REP values and the TEQCALUX. Even though, for most AhR agonists, the sensitivity of herring gulls is not known, the reported levels can be considered to represent a risk for biological effects in the developing embryo, compared to LC50 values in chicken embryos. For human consumers of herring gull eggs, these eggs contain TEQ levels up to four times higher than the maximum tolerable weekly intake. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Hepatic EROD activity is not a useful biomarker of polychlorinated biphenyl exposure in the adult herring gull (Larus argentatus).

    PubMed

    Kennedy, Sean W; Fox, Glen A; Jones, Stephanie P; Trudeau, Suzanne F

    2003-01-01

    Liver concentrations of polychlorinated biphenyls (PCBs) and chicken embryo hepatocyte (CEH) bioassay-derived 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQs) were measured in livers of adult herring gulls (Larus argentatus) collected from several locations on the Great Lakes and two reference sites. Total PCB concentrations (sum of 42 congeners) and TCDD-EQ concentrations were compared with hepatic ethoxyresorufin-O-deethylase (EROD) activity, methoxyresorufin-O-deethylase (MROD) activity and immunodetectable cytochrome P4501A (CYP1A) protein concentration. EROD and MROD activity were not significantly correlated with total PCB concentration or TCDD-EQ concentration in liver tissue. CYP1A protein concentration was significantly correlated with total PCB concentration, but the linear relationship had little predictive power. We conclude that EROD is not a useful biomarker of PCB exposure in the adult herring gull.

  19. Early maternal, genetic and environmental components of antioxidant protection, morphology and immunity of yellow-legged gull (Larus michahellis) chicks.

    PubMed

    Rubolini, D; Romano, M; Bonisoli Alquati, A; Saino, N

    2006-09-01

    Maternal effects mediated by egg quality are important sources of offspring phenotypic variation and can influence the course of evolutionary processes. Mothers allocate to the eggs diverse antioxidants that protect the embryo from oxidative stress. In the yellow-legged gull (Larus michahellis), yolk antioxidant capacity varied markedly among clutches and declined considerably with egg laying date. Analysis of bioptic yolk samples from clutches that were subsequently partially cross-fostered revealed a positive effect of yolk antioxidant capacity on embryonic development and chick growth, but not on immunity and begging behaviour, while controlling for parentage and common environment effects. Chick plasma antioxidant capacity varied according to rearing environment, after statistically partitioning out maternal influences mediated by egg quality. Thus, the results of this study indicate that egg antioxidants are important mediators of maternal effects also in wild bird populations, especially during the critical early post-hatching phase.

  20. Nesting biology of laughing gulls Larus atricilla in relation to agricultural chemicals in south Texas USA 1978-1981

    USGS Publications Warehouse

    White, D.H.; Mitchell, C.A.; Prouty, R.M.

    1983-01-01

    Various aspects of the breeding biology of Laughing Gulls (Larus atricilla) have been studied extensively in Florida (Dinsmore and Schreiber 1974, Schreiber et al. 1979, Schreiber and Schreiber 1980), New Jersey (Bongiorno 1970, Burger and Beer 1976, Burger 1976, Montevecchi 1978), and Massachusetts (Noble and Wurm 1943), but little is known of their yearly fledging success in Texas or elsewhere. The Laughing Gull is a common colonial nester along most of the Texas coast, second only to the Cattle Egret (Bubulcus ibis) in breeding abundance; however, the Laughing Gull may be threatened in Texas because of suspected declines at certain traditional nesting locales (Blacklock et al. 1979). Since Laughing Gulls often nest in proximity to agricultural and industrial areas, we were concerned that environmental pollutants might be adversely affecting productivity. In 1978-1981 we conducted studies along the south Texas coast to learn more about the nesting ecology of Laughing Gulls and to evaluate the effects of environmental contaminants on reproduction.

  1. Organochlorine contaminants in the muscle, liver and brain of seabirds (Larus) from the coastal area of the Southern Baltic.

    PubMed

    Falkowska, Lucyna; Reindl, Andrzej R; Grajewska, Agnieszka; Lewandowska, Anita U

    2016-11-01

    The presence of persistent organic pollutants in the environment manifests itself most strongly in the marine trophic chain, where the highest link is comprised of seabirds. At the same time, seabirds are excellent indicators of contamination in their habitat. The present study concentrates on toxic substances: polychlorinated dibenzo-p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs) and chlorinated organic pesticides (OCPs) accumulated in the livers, pectoral muscles and brains of dead gulls collected along the Polish coast of the Baltic Sea in the years 2010-12. The highest toxic equivalence was determined in the livers of Larus argentatus (TEQ(birds TEF)-28.3pgg(-1) ww) and Larus marinus (TEQ(birds TEF)-29.9pgg(-1) ww.). However, the toxic equivalence of muscles was lower and amounted to 3.9pgg(-1) ww. and 7.8pgg(-1) ww. respectively for the two species. The lowest toxic equivalence was found in the brains of birds, where only one, the most toxic, 2,3,7,8 TCDD congener was found (TEQ(birds TEF) 0.87pgg(-1) ww). The highest concentration of chloroorganic pesticides was determined in the brains of the birds (total OCP 167.8pgg(-1) ww.), lower concentrations were found in the livers (total OCP 92.1pgg(-1) ww.) and muscles (total OCP 43.1pgg(-1) ww.). With regard to pesticides, the highest proportion in the total OCP content was constituted by DDT and its isomers (liver 81%, muscles 77% and brain 55%). High concentrations of the studied pollutants in the livers of gulls found dead on the coast of the Southern Baltic could have been effected by levels of contamination in the birds' last meals, which resulted in a seven-fold increase of the liver's toxic equivalence and a two-fold increase in OCP concentration in relation to muscles.

  2. Effects of contaminant exposure and food restriction on hepatic autophagic lysosomal parameters in Herring Gull (Larus argentatus) chicks.

    PubMed

    Hegseth, Marit Nøst; Gorbi, Stephania; Bocchetti, Raffaella; Camus, Lionel; Gabrielsen, Geir Wing; Regoli, Francesco

    2014-08-01

    Lysosomal autophagic responses, such as lysosomal membrane stability, neutral lipids (NL), lipofuscin (LF), and malondialdehyde (MDA) levels, are valuable measures of cellular early-onset effects induced by environmental stress factors, such as contaminant exposure and fasting. In this study, these parameters were analysed and related to levels of halogenated organic contaminants (HOCs) in 40 Herring Gull (Larus argentatus) chicks. Chicks were experimentally exposed to HOCs through diet and went through a period of nutrient deprivation at the end of the experiment. HOC exposure and fasting were conducted separately and in combination. NL storages were depleted, and lysosomal membranes were destabilised after HOC exposure and nutrient deprivation. These responses were not related specifically to one type of stress or the extent of the treatment. No synergistic or additive effects from the combination of HOC exposure and fasting were observed. LF accumulated, and MDA levels increased as a result of fasting, but were unaffected by HOC exposure. LF accumulation was strongly associated with the percent weight change in the chicks. Large weight loss was associated with high LF levels, and slight weight gain was associated with low LF levels. Hence, food deprivation affected all the measured parameters, and HOC exposure decreased NL levels and lysosomal membrane stability in HG chick liver. Furthermore, autophagic lysosomal parameters have frequently been applied as biomarkers of cellular health status in previous studies of marine and terrestrial invertebrates, and this study suggests that these parameters may be good candidates for biomarkers of cellular health status in seabirds as well.

  3. Trace element concentrations in eggshells and egg contents of black-tailed gull (Larus crassirostris) from Korea.

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2014-09-01

    Concentrations of trace elements (cadmium, lead, copper, manganese and zinc) were examined in eggs of black-tailed gulls (Larus crassirostris) from Hongdo Island, Korea to determine the difference and distribution of trace elements in eggshells and egg contents. Cadmium, lead and manganese concentrations were greater in eggshells than in egg contents. In contrast, zinc concentrations were higher in egg contents than in eggshells. Trace element concentrations followed the order: zinc > lead = manganese = copper > cadmium (eggshells) and zinc > copper > manganese > lead > cadmium (egg contents). Cadmium concentrations were relatively low (<1 μg/g dw) in egg contents and eggshells. Concentrations of cadmium, lead and copper were significantly correlated between egg contents and eggshells. This indicates that cadmium, lead and copper levels in the eggshell can reflect their levels in the egg contents. There was also a high ratio (3.2) of eggshell/egg content for lead. These results indicate that the eggshell might be useful as a bio-indicator for monitoring cadmium, lead and copper in the egg content.

  4. Evidence of weak contaminant-related oxidative stress in glaucous gulls (Larus hyperboreus) from the Canadian Arctic.

    PubMed

    Wayland, Mark; Hoffman, David J; Mallory, Mark L; Alisauskas, Ray T; Stebbins, Katherine R

    2010-01-01

    Environmental contaminants are transported over great distances to Arctic ecosystems, where they can accumulate in wildlife. Whether contaminant concentrations in wildlife are sufficient to produce adverse effects remains poorly understood. Exposure to contaminants elevates oxidative stress with possible fitness consequences. The glaucous gull (Larus hyperboreus), an Arctic top predator, was used as a bioindicator for investigating relationships between contaminant levels (organochlorines and polychlorinated biphenyls [OC/PCB], mercury [Hg], and selenium [Se]) and measures of oxidative stress (glutathione [GSH] metabolism and lipid peroxidation) in Canadian Arctic ecosystems. Contaminant levels were low and associations between contaminant exposure and oxidative stress were weak. Nevertheless, glutathione peroxidase activity rose with increasing hepatic Se concentrations, levels of thiols declined as Hg and OC/PCB levels rose, and at one of the two study sites levels of lipid peroxidation were elevated with increasing levels of hepatic Hg. These results suggest the possibility of a deleterious effect of exposure to contaminants on gull physiology even at low contaminant exposures.

  5. Variation in Immune Parameters and Disease Prevalence among Lesser Black-Backed Gulls (Larus fuscus sp.) with Different Migratory Strategies

    PubMed Central

    Arriero, Elena; Müller, Inge; Juvaste, Risto; Martínez, Francisco Javier; Bertolero, Albert

    2015-01-01

    The ability to control infections is a key trait for migrants that must be balanced against other costly features of the migratory life. In this study we explored the links between migration and disease ecology by examining natural variation in parasite exposure and immunity in several populations of Lesser Black-backed Gulls (Larus fuscus) with different migratory strategies. We found higher activity of natural antibodies in long distance migrants from the nominate subspecies L.f.fuscus. Circulating levels of IgY showed large variation at the population level, while immune parameters associated with antimicrobial activity showed extensive variation at the individual level irrespective of population or migratory strategy. Pathogen prevalence showed large geographical variation. However, the seroprevalence of one of the gull-specific subtypes of avian influenza (H16) was associated to the migratory strategy, with lower prevalence among the long-distance migrants, suggesting that migration may play a role in disease dynamics of certain pathogens at the population level. PMID:25679797

  6. Variation in immune parameters and disease prevalence among Lesser Black-backed Gulls (Larus fuscus sp.) with different migratory strategies.

    PubMed

    Arriero, Elena; Müller, Inge; Juvaste, Risto; Martínez, Francisco Javier; Bertolero, Albert

    2015-01-01

    The ability to control infections is a key trait for migrants that must be balanced against other costly features of the migratory life. In this study we explored the links between migration and disease ecology by examining natural variation in parasite exposure and immunity in several populations of Lesser Black-backed Gulls (Larus fuscus) with different migratory strategies. We found higher activity of natural antibodies in long distance migrants from the nominate subspecies L.f.fuscus. Circulating levels of IgY showed large variation at the population level, while immune parameters associated with antimicrobial activity showed extensive variation at the individual level irrespective of population or migratory strategy. Pathogen prevalence showed large geographical variation. However, the seroprevalence of one of the gull-specific subtypes of avian influenza (H16) was associated to the migratory strategy, with lower prevalence among the long-distance migrants, suggesting that migration may play a role in disease dynamics of certain pathogens at the population level.

  7. Antimicrobial Resistance of Salmonella Serovars and Campylobacter spp. Isolated from an Opportunistic Gull Species, Yellow-legged Gull ( Larus michahellis ).

    PubMed

    Migura-Garcia, Lourdes; Ramos, Raül; Cerdà-Cuéllar, Marta

    2017-01-01

    Wildlife is a natural reservoir of Salmonella and Campylobacter, the most important human foodborne pathogens worldwide. Free-living birds have the potential to transport, over large distances, such zoonotic bacteria that may harbor antimicrobial resistance traits. On the northeastern Iberian coast, we assessed the role of Yellow-legged Gulls ( Larus michahellis ) as reservoirs of antimicrobial resistance in Salmonella and thermophilic Campylobacter isolates recovered from gulls at three colonies, with varying degrees of dependence on refuse dumps as food sources. Of the 39 Salmonella isolates we tested, 17 were multiresistant (resistance to three antimicrobial families), with eight being Salmonella enterica serovar Typhimurium. Other clinically relevant Salmonella serovars showing multiresistance included Hadar, Bredeney, and Virchow. Relevant Campylobacter antimicrobial resistances were detected among three Campylobacter jejuni isolates, of which all three showed resistance to nalidixic acid, two were resistant to ciprofloxacin, one was resistant to enrofloxacin, and one was resistant to tetracycline. Our results highlight the importance of free-living gulls with opportunistic feeding habits in the dissemination of enteric pathogens resistant to multiple antimicrobial agents of public health concern.

  8. Diets of nesting laughing gulls (Larus atricilla) at the Virginia Coast Reserve: observations from stable isotope analysis.

    PubMed

    Knoff, A J; Macko, S A; Erwin, R M

    2001-01-01

    Food web studies often ignore details of temporal, spatial, and intrapopulation dietary variation in top-level consumers. In this study, intrapopulation dietary variation of a dominant carnivore, the Laughing Gull (Larus atricilla), was examined using carbon, nitrogen, and sulfur isotope analysis of gull tissues as well as their prey (fish, invertebrates, and insects) from the Virginia Coast Reserve estuarine system. As earlier traditional diet studies found evidence of individual dietary specialization within gull populations, this study used stable isotope analysis to assess specialization in a coastal Laughing Gull population. Specifically, blood, muscle, and feather isotope values indicated significant intrapopulation dietary specialization. Some gulls relied more heavily on estuarine prey (mean blood delta13C = -17.5, delta15N = 12.6, and delta34S = 9.3), whereas others appeared to consume more foods of marine origin (mean blood delta13C = -19.4, delta15N = 14.8, and delta34S = 10.4). It is important to account for such dietary variability when assessing trophic linkages in dynamic estuarine systems.

  9. Diets of nesting laughing gulls (Larus atricilla) at the Virginia Coast Reserve: observations from stable isotope analysis

    USGS Publications Warehouse

    Knoff, A.J.; Macko, S.A.; Erwin, R.M.

    2001-01-01

    Food web studies often ignore details of temporal, spatial, and intrapopulation dietary variation in top-level consumers. In this study, intrapopulation dietary variation of a dominant carnivore, the Laughing Gull (Larus atricilla), was examined using carbon, nitrogen, and sulfur isotope analysis of gull tissues as well as their prey (fish, invertebrates, and insects) from the Virginia Coast Reserve estuarine system. As earlier traditional diet studies found evidence of individual dietary specialization within gull populations, this study used stable isotope analysis to assess specialization in a coastal Laughing Gull population. Specifically, blood, muscle, and feather isotope values indicated significant intrapopulation dietary specialization. Some gulls relied more heavily on estuarine prey (mean blood δ13C = -17.5, δ15N = 12.6, and δ34S = 9.3), whereas others appeared to consume more foods of marine origin (mean blood δ13C = -19.4, δ15N = 14.8, and δ34S = 10.4). It is important to account for such dietary variability when assessing trophic linkages in dynamic estuarine systems.

  10. Egg Production in a Coastal Seabird, the Glaucous-Winged Gull (Larus glaucescens), Declines during the Last Century

    PubMed Central

    Blight, Louise K.

    2011-01-01

    Seabirds integrate information about oceanic ecosystems across time and space, and are considered sensitive indicators of marine conditions. To assess whether hypothesized long-term foodweb changes such as forage fish declines may be reflected in a consumer's life history traits over time, I used meta-regression to evaluate multi-decadal changes in aspects of egg production in the glaucous-winged gull (Larus glaucescens), a common coastal bird. Study data were derived from literature searches of published papers and unpublished historical accounts, museum egg collections, and modern field studies, with inclusion criteria based on data quality and geographic area of the original study. Combined historical and modern data showed that gull egg size declined at an average of 0.04 cc y−1 from 1902 (108 y), equivalent to a decline of 5% of mean egg volume, while clutch size decreased over 48 y from a mean of 2.82 eggs per clutch in 1962 to 2.25 in 2009. There was a negative relationship between lay date and mean clutch size in a given year, with smaller clutches occurring in years where egg laying commenced later. Lay date itself advanced over time, with commencement of laying presently (2008–2010) 7 d later than in previous studies (1959–1986). This study demonstrates that glaucous-winged gull investment in egg production has declined significantly over the past ∼50–100 y, with such changes potentially contributing to recent population declines. Though gulls are generalist feeders that should readily be able to buffer themselves against food web changes, they are likely nutritionally constrained during the early breeding period, when egg production requirements are ideally met by consumption of high-quality prey such as forage fish. This study's results suggest a possible decline in the availability of such prey, and the incremental long-term impoverishment of a coastal marine ecosystem bordering one of North America's rapidly growing urban areas. PMID

  11. Seasonal dispersal and longitudinal migration in the Relict Gull Larus relictus across the Inner-Mongolian Plateau.

    PubMed

    Liu, Dongping; Zhang, Guogang; Jiang, Hongxing; Chen, Lixia; Meng, Derong; Lu, Jun

    2017-01-01

    The Relict Gull Larus relictus is a globally vulnerable species and one of the least known birds, so understanding its seasonal movements and migration will facilitate the development of effective conservation plans for its protection. We repeatedly satellite-tracked 11 adult Relict Gulls from the Ordos sub-population in Hongjian Nur, China, over 33 migration seasons and conducted extensive ground surveys. Relict Gulls traveled ∼800 km between Hongjian Nur in northern China to the coast of eastern China in a predominantly longitudinal migration, following a clockwise loop migration pattern. The gulls migrated faster in spring (4 ± 2 d) than in autumn (15 ± 13 d) due to a time-minimization strategy for breeding, and they showed considerable between-individual variation in the timing of the autumn migration, probably due to differences in the timing of breeding. Gulls that made at least two round trips exhibited high flexibility in spring migration timing, suggesting a stronger influence of local environment conditions over endogenous controls. There was also high route flexibility among different years, probably due to variations in meteorological or habitat conditions at stopover sites. Relict Gulls stayed for a remarkably long time (234 ± 17 d) on their major wintering grounds in Bohai Bay and Laizhou Bay, between which there were notable dispersals. Pre-breeding dispersals away from the breeding area were distinct, which seemed to be a strategy to cope with the degradation of breeding habitat at Hongjian Nur. Overwhelming lake shrinkage on the breeding ground and at stopover sites and loss of intertidal flats on the wintering grounds are regarded as the main threats to Relict Gulls. It is crucial to make protection administrations aware of the great significance of key sites along migration routes and to promote the establishment of protected areas in these regions.

  12. Seasonal dispersal and longitudinal migration in the Relict Gull Larus relictus across the Inner-Mongolian Plateau

    PubMed Central

    Liu, Dongping; Jiang, Hongxing; Chen, Lixia; Meng, Derong; Lu, Jun

    2017-01-01

    The Relict Gull Larus relictus is a globally vulnerable species and one of the least known birds, so understanding its seasonal movements and migration will facilitate the development of effective conservation plans for its protection. We repeatedly satellite-tracked 11 adult Relict Gulls from the Ordos sub-population in Hongjian Nur, China, over 33 migration seasons and conducted extensive ground surveys. Relict Gulls traveled ∼800 km between Hongjian Nur in northern China to the coast of eastern China in a predominantly longitudinal migration, following a clockwise loop migration pattern. The gulls migrated faster in spring (4 ± 2 d) than in autumn (15 ± 13 d) due to a time-minimization strategy for breeding, and they showed considerable between-individual variation in the timing of the autumn migration, probably due to differences in the timing of breeding. Gulls that made at least two round trips exhibited high flexibility in spring migration timing, suggesting a stronger influence of local environment conditions over endogenous controls. There was also high route flexibility among different years, probably due to variations in meteorological or habitat conditions at stopover sites. Relict Gulls stayed for a remarkably long time (234 ± 17 d) on their major wintering grounds in Bohai Bay and Laizhou Bay, between which there were notable dispersals. Pre-breeding dispersals away from the breeding area were distinct, which seemed to be a strategy to cope with the degradation of breeding habitat at Hongjian Nur. Overwhelming lake shrinkage on the breeding ground and at stopover sites and loss of intertidal flats on the wintering grounds are regarded as the main threats to Relict Gulls. It is crucial to make protection administrations aware of the great significance of key sites along migration routes and to promote the establishment of protected areas in these regions. PMID:28560115

  13. Gene expression, glutathione status and indicators of hepatic oxidative stress in laughing gull (Larus atricilla) hatchlings exposed to methylmercury

    USGS Publications Warehouse

    Jenko, Kathryn; Karouna-Renier, Natalie K.; Hoffman, David J.

    2012-01-01

    Despite extensive studies of methylmercury (MeHg) toxicity in birds, molecular effects on birds are poorly characterized. To improve our understanding of toxicity pathways and identify novel indicators of avian exposure to Hg, the authors investigated genomic changes, glutathione status, and oxidative status indicators in liver from laughing gull (Larus atricilla) hatchlings that were exposed in ovo to MeHg (0.05–1.6 µg/g). Genes involved in the transsulfuration pathway, iron transport and storage, thyroid-hormone related processes, and cellular respiration were identified by suppression subtractive hybridization as differentially expressed. Quantitative polymerase chain reaction (qPCR) identified statistically significant effects of Hg on cytochrome C oxidase subunits I and II, transferrin, and methionine adenosyltransferase RNA expression. Glutathione-S-transferase activity and protein-bound sulfhydryl levels decreased, whereas glucose-6-phosphate dehydrogenase activity increased dose-dependently. Total sulfhydryl concentrations were significantly lower at 0.4 µg/g Hg than in controls. T ogether, these endpoints provided some evidence of compensatory effects, but little indication of oxidative damage at the tested doses, and suggest that sequestration of Hg through various pathways may be important for minimizing toxicity in laughing gulls. This is the first study to describe the genomic response of an avian species to Hg. Laughing gulls are among the less sensitive avian species with regard to Hg toxicity, and their ability to prevent hepatic oxidative stress may be important for surviving levels of MeHg exposures at which other species succumb.

  14. Mercury and other metals in eggs and feathers of glaucous-winged gulls (Larus glaucescens) in the Aleutians

    PubMed Central

    Gochfeld, Michael; Jeitner, Christian; Burke, Sean; Volz, Conrad D.; Snigaroff, Ronald; Snigaroff, Daniel; Shukla, Tara; Shukla, Sheila

    2014-01-01

    Levels of mercury and other contaminants should be lower in birds nesting on isolated oceanic islands and at high latitudes without any local or regional sources of contamination, compared to more urban and industrialized temperate regions. We examined concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in the eggs, and the feathers of fledgling and adult glaucous-winged gulls (Larus glaucescens) nesting in breeding colonies on Adak, Amchitka, and Kiska Islands in the Aleutian Chain of Alaska in the Bering Sea/North Pacific. We tested the following null hypotheses: 1) There were no differences in metal levels among eggs and feathers of adult and fledgling glaucous-winged gulls, 2) There were no differences in metal levels among gulls nesting near the three underground nuclear test sites (Long Shot 1965, Milrow 1969, Cannikin 1971) on Amchitka, 3) There were no differences in metal levels among the three islands, and 4) There were no gender-related differences in metal levels. All four null hypotheses were rejected at the 0.05 level, although there were few differences among the three test sites on Amchitka. Eggs had the lowest levels of cadmium, lead, and mercury, and the feathers of adults had the lowest levels of selenium. Comparing only adults and fledglings, adults had higher levels of cadmium, chromium, lead and mercury, and fledglings had higher levels of arsenic, manganese and selenium. There were few consistent interisland differences, although levels were generally lower for eggs and feathers from gulls on Amchitka compared to the other islands. Arsenic was higher in both adult feathers and eggs from Amchitka compared to Adak, and chromium and lead were higher in adult feathers and eggs from Adak compared to Amchitka. Mercury and arsenic, and chromium and manganese levels were significantly correlated in the feathers of both adult and fledgling gulls. The feathers of males had significantly higher levels of chromium and

  15. A transactional analysis of changes in parent and chick behaviour prior to separation of Herring Gulls (Larus Argentatus): A three-term contingency model.

    PubMed

    Reed, Phil

    2015-09-01

    The effect of the passage of time on parent-offspring behaviour of urban Herring Gulls (Larus Argentatus) was studied and analysed using a three-term contingency model. A behavioural sequence was initiated by the arrival of a parental adult gull, which would lead to feeding in the chick. However, with the passage of time, and approach of the separation period, this pattern changed. Chicks' begging became more intense, and parent gulls more often withheld food. However, the chicks' begging became directed at a wider range of adults over the observation period. These activities are placed within a three-term contingency model, which may have implications for understanding some behavioural processes involved in parent-offspring separation.

  16. Complete genome analysis of an avian paramyxovirus type 1 strain isolated in 1994 from an asymptomatic black-headed gull (Larus ridibundus) in southern Sweden.

    PubMed

    Munir, Muhammad; Linde, Anna-Malin; Zohari, Siamak; Ståhl, Karl; Baule, Claudia; Holm, Kerstin; Engström, Björn; Berg, Mikael

    2010-06-01

    The complete genome sequence of an avian paramyxovirus serotype 1 (APMV-1) isolated from a black-headed gull (Larus ridibundus) in Sweden was determined and compared with other APMV-1 sequences. Sequence analyses showed that this isolate consists of six genes in the order 3'-NP-P-M-F-HN-L-5', is 15,186 nucleotides long, and contains a typical, avirulent fusion protein cleavage site. It was also shown to have a hemagglutinin-neuraminidase protein with a length of 585 amino acids (aa) instead of the expected 616 aa. Phylogenetic analyses showed that the isolate belongs to genotype I, and the relationship with some other, known APMV-1 virus sequences was revealed. Waterfowl have been considered to act as a reservoir for APMV-1 and, therefore, it is important to broaden the knowledge of viruses circulating within this population.

  17. Enterobacter cloacae with a novel variant of ACT AmpC beta-lactamase originating from glaucous gull (Larus hyperboreus) in Svalbard.

    PubMed

    Literak, Ivan; Manga, Ivan; Wojczulanis-Jakubas, Katarzyna; Chroma, Magdalena; Jamborova, Ivana; Dobiasova, Hana; Sedlakova, Miroslava Htoutou; Cizek, Alois

    2014-07-16

    We aimed at Escherichia coli and Enterobacter cloacae isolates resistant to cephalosporins and fluoroquinolones and Salmonella isolates in wild birds in Arctic Svalbard, Norway. Cloacal swabs of little auks (Alle alle, n=215) and samples of faeces of glaucous gulls (Larus hyperboreus, n=15) were examined. Inducible production of AmpC enzyme was detected in E. cloacae KW218 isolate. Sequence analysis of the 1146 bp PCR product of the ampC gene from this isolate revealed 99% sequence homology with the blaACT-14 and blaACT-5 AmpC beta-lactamase genes. Four, respectively six of the identified single nucleotide polymorphisms generated amino acid substitutions in the amino acid chain. As the ampC sequence polymorphism in the investigated E. cloacae strain was identified as unique, we revealed a novel variant of the ampC beta-lactamase gene blaACT-23.

  18. Polychlorinated camphenes (toxaphenes), polybrominated diphenylethers and other halogenated organic pollutants in glaucous gull (Larus hyperboreus) from Svalbard and Bjørnøya (Bear Island).

    PubMed

    Herzke, Dorte; Gabrielsen, Geir Wing; Evenset, Anita; Burkow, Ivan C

    2003-01-01

    The levels of polychlorinated camphenes (toxaphenes) were investigated in liver samples from 18 glaucous gulls (Larus hyperboreus) from Bjørnøya (74 degrees N, 19 degrees E) and four individuals from Longyearbyen (78 degrees N, 15 degrees E). Additionally brominated flame retardants (BFRs), PCBs and chlorinated pesticides were investigated in liver and intestinal contents of 15 of the glaucous gulls from Bjørnøya. Of the analysed BFRs only 2,2',4,4'-tetra- and 2,2',4,4',5-pentabrominated diphenylethers (PBDE 47 and 99) could be detected. The concentrations ranged between 2 and 25 ng/g ww. In addition, high resolution measurements with GC/HRMS revealed the existence of several, not quantified, PBDEs and polybrominated biphenyls (PBBs) congeners in the samples. B9-1679 and B8-1413 were the dominating toxaphenes with median concentrations of 8 and 15 ng/g ww. Concentrations of toxaphenes and PBDEs were up to 100-times lower than the concentrations of PCB and some of the pesticides. PCB and p,p/-DDE constituted 90% of the contaminants found.

  19. Developmental toxicity of PFOS and PFOA in great cormorant (Phalacrocorax carbo sinensis), herring gull (Larus argentatus) and chicken (Gallus gallus domesticus).

    PubMed

    Nordén, Marcus; Berger, Urs; Engwall, Magnus

    2016-06-01

    Perfluoroalkyl acids (PFAAs) are found globally in environmental samples and have been studied in various species. In this study, we compare the sensitivity of three avian species to the toxic effects of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA). Eggs of great cormorant (Phalacrocorax carbo sinensis), herring gull (Larus argentatus) and the domestic White Leghorn chicken (Gallus gallus domesticus) were exposed in ovo by injection into the air sac. Effects on embryo survival were observed following exposure to PFOS and PFOA in chicken and herring gull. Chicken was found to be the most sensitive species with 50 % reduced embryo survival at 8.5 μg/g egg for PFOS and 2.5 μg/g egg for PFOA. Cormorant was shown to be the least sensitive species. The difference in sensitivity between chicken and herring gull was a factor of 2.7 for PFOS and 3.5 for PFOA. Between chicken and great cormorant, the sensitivity difference was 2.6 for PFOS and 8.2 for PFOA. Effects on embryo survival were seen at egg injection doses of PFOS close to levels found in environmental samples from wild birds, indicating that PFOS could be having effects in highly exposed populations of birds. This study also shows that there are differences in species sensitivity to PFOS and PFOA that should be taken into consideration in avian wildlife risk assessment.

  20. Characterization and locus-specific typing of MHC class I genes in the red-billed gull (Larus scopulinus) provides evidence for major, minor, and nonclassical loci.

    PubMed

    Cloutier, Alison; Mills, James A; Baker, Allan J

    2011-06-01

    A major challenge facing studies of major histocompatibility complex (MHC) evolution in birds is the difficulty in genotyping alleles at individual loci, and the consequent inability to investigate sequence variation and selection pressures for each gene. In this study, four MHC class I loci were isolated from the red-billed gull (Larus scopulinus), representing both the first characterized MHCI genes within Charadriiformes (shorebirds, gulls, and allies) and the first full-length MHCI sequences described outside Galloanserae (gamebirds + waterfowl). Complete multilocus genotypes were obtained for 470 individuals using a combination of reference-strand conformation analysis and direct sequencing of gene-specific amplification products, and variation of peptide-binding region (PBR) exons was surveyed for all loci. Each gene is transcribed and has conserved sequence features characteristic of antigen-presenting MHCI molecules. However, higher allelic variation, a more even allele frequency distribution, and evidence of positive selection acting on a larger number of PBR residues suggest that only one locus (Lasc-UAA) functions as a major classical MHCI gene. Lasc-UBA, with more limited variation and PBR motifs that encompass a subset of Lasc-UAA diversity, was assigned a putative minor classical function, whereas the divergent and largely invariant binding-groove motifs of Lasc-UCA and -UDA are suggestive of nonclassical loci with specialized ligand-binding roles.

  1. Effect of rapid modulation of circulating plasma testosterone concentration on begging, aggressive behavior and competition for food in black-headed gull (Larus ridibundus) chicks.

    PubMed

    Boncoraglio, Giuseppe; Groothuis, Ton G G

    2013-08-01

    Sibling competition mediated by begging behavior is extremely common in avian species and recent studies have highlighted the role of endogenous testosterone in regulating such phenomenon. However, current literature depicts an inconsistent pattern in altricial vs. semi-precocial species, with stimulating versus inhibitory effects of the hormone respectively. This is possibly due to a difference in the methodology of hormone treatment (short-term moderate dose versus a long-term stronger elevation, respectively) between the studies performed so far. In this study, we induced short-term moderate peaks in plasma testosterone levels, as applied in altricial bird species, and assessed the effects of our manipulation on begging, competitive and aggressive behavior in black-headed gull (Larus ridibundus) chicks, a semi-precocial species. Our results suggest that, unlike in altricial songbirds, temporary increase of plasma testosterone concentration suppresses begging and enhances aggressiveness towards intruders. However, it also increases aggression and the chances of getting priority while scrambling with nest mates to gain access to food. Thus, the inconsistencies in the hormonal control of begging behavior observed between altricial vs. semi-precocial birds seem real and perhaps related to species differences in complexity of the display and the nature of competition. These may be elucidated by future comparative studies.

  2. [Dynamics of physiological parameters in the nestling of black-backed gull Larus marinus experimentally infested by the cestode Microsomacanthus ductilus (Cestoda: Hymenolepididae)].

    PubMed

    Kuklina, M M; Kuklin, V V

    2008-01-01

    The effect of the invasion with the cestode Microsomacanthus ductilus on physiological and biochemical processes in black-backed gull Larus marinus was examined. Experimental invasion of the gull nestling by the cestodes has been performed. Dynamics of the protein, lipid, and carbohydrate metabolism in the time history of the invasion was observed, in comparison with noninfested nestling. Increasing of the content of alpha-globulins and decreasing of the content of protein and albumin in the blood plasma of experimentally infested birds were registered to 4th day after invasion. To 7th day after invasion the level of general lipids and phospholipids decreases, while the content of gamma-globulins and modified form of albumin increases. To 10th day after invasion symptoms of intoxication were observed, but some parameters proved to be reverted to normal condition. So, it can be assumed, that the most intensive reorganization of the metabolism in infested birds takes place in the period between 4th and 7th days after infestation. Possible causes of the observed phenomena are discussed.

  3. Description of Sarcocystis lari sp. n. (Apicomplexa: Sarcocystidae) from the great black-backed gull, Larus marinus (Charadriiformes: Laridae), on the basis of cyst morphology and molecular data.

    PubMed

    Prakas, Petras; Kutkiené, Liuda; Butkauskas, Dalius; Sruoga, Aniolas; Zalakevicius, Mecislovas

    2014-02-01

    A morphological type of Sarcocystis cysts found in one of two examined great black-backed gull, Larus marinus (Linnaeus) (Laridae), is considered to represent a new species for which the name Sarcocystis lari sp. n. is proposed and its description is provided. The cysts are ribbon-shaped, very long (the largest fragment found was 6 mm long) and relatively narrow (up to 75 microm). Under a light microscope the cyst wall reaches up to 1 microm and seems to be smooth. Using a computerized image analysis system, knolls, which resemble protrusions on the wall surface, are visible. Lancet-shaped cystozoites measure in average 6.9 x 1.4 microm (range 6.3-7.9 microm x 1.2-1.5 microm) in length. Observed using Transmission electron microscopy (TEM), the cyst wall is wavy and measures up to 1.2 microm in thickness. The parasitophorous vacuolar membrane has regularly arranged small invaginations. Cyst content is divided into large chambers by septa. Sarcocystis lari sp. n. has type-1 tissue cyst wall and is morphologically indistinguishable from other bird Sarcocystis species characterized by the same type of the wall. On the basis of 18S rRNA gene, 28S rRNA gene and ITS-1 region sequences, S. lari is a genetically distinct species, being most closely related to avian Sarcocystis species whose definitive hosts are predatory birds.

  4. Foraging movements of Audouin’s gull (Larus audouinii) in the Ebro Delta, NW Mediterranean: A preliminary satellite-tracking study

    NASA Astrophysics Data System (ADS)

    Christel, Isadora; Navarro, Joan; del Castillo, Marcos; Cama, Albert; Ferrer, Xavier

    2012-01-01

    A knowledge of the foraging strategies of marine predators is essential to understand the intrinsic factors controlling their distribution, abundance and their ecological function within the marine ecosystem. Here, we investigated for the first time the foraging movements and activity patterns of Audouin's gull Larus audouinii by using satellite-tracking data from eight breeding adults in the main colony of the species worldwide (Ebro Delta, NW Mediterranean). Tagged gulls foraged in the marine area close to the breeding colony (62% of foraging locations) and in the terrestrial area of the Ebro Delta (mainly rice fields; 38% of foraging locations). The foraging activity patterns changed significantly throughout the day; lower from dusk through the first half of the night (19-1 h; 32% of active locations) and higher during the rest of the day (1-19 h; 75.5 ± 4.3% of active locations). These results confirm the foraging plasticity of this seabird and, based on previous information about the dietary habits of this species, we hypothesize how its time-dependent activity patterns and habitat use could be associated with variations in the availability of marine food resources (e.g. diel vertical migrations of pelagic fish) and the exploitation of terrestrial resources (e.g. American crayfish Procambarus clarkii).

  5. Heavy metal contamination and metallothionein mRNA in blood and feathers of Black-tailed gulls (Larus crassirostris) from South Korea.

    PubMed

    Kim, Miran; Park, Kiyun; Park, Jin Young; Kwak, Inn-Sil

    2013-03-01

    The objectives of this study were to determine levels of heavy metal in the feathers and blood of Black-tailed gulls (Larus crassirostris), to evaluate metallothionein (MT) mRNA level in Black-tailed gulls on three independent islets, and to examine the correlation between heavy metal concentrations and MT mRNA expression. Eleven heavy metals (Al, Cd, Mn, Pb, Cr, Fe, Cu, Zn, Se, Hg, and As) were investigated in blood and feathers of 65 chicks from breeding colonies (Seomando, Hongdo, and Dokdo islet) of South Korea in 2010. Heavy metals were assayed by PerkinElmer NexION 300 inductively coupled plasma mass spectrometry. The mean concentrations of non-essential heavy metals were found to blood containing Cd (0.002 ~ 0.02 ppm), Pb (0.06 ~ 0.18) ppm, Hg (0.03 ~ 0.05) ppm, and As (0.26 ~ 0.48 ppm), and feather containing Cd (0.05 ~ 0.30 ppm), Pb (2.47 ~ 10.80 ppm), Hg (1.18 ~ 1.57 ppm), and As (0.15 ~ 0.44 ppm). Chicks on Seomando islet showed the highest levels of metals (Cd, Pb, Mn, Cr, Cu, and Se in blood; Al, As, Mn, Cr, Fe, Cu, and Se in feathers) among the colonies. Concentrations of Pb and Hg in feathers were the highest on Hongdo, and the levels of Cd and Zn in feathers were the highest on Dokdo islet. MT mRNA in the blood of Black-tailed gulls was relatively higher in gulls from Seomando than in gulls from Hongdo and Dokdo islet. MT mRNA level is thus positively correlated to heavy metal concentrations in Black-tailed gulls.

  6. Isomers of Dechlorane Plus flame retardant in the eggs of herring gulls (Larus argentatus) from the Laurentian Great Lakes of North America: temporal changes and spatial distribution.

    PubMed

    Gauthier, Lewis T; Letcher, Robert J

    2009-03-01

    Dechlorane Plus (DP) is a chlorinated flame retardant (FR) comprised of two major structural isomers, syn and anti. For the Laurentian Great Lakes of North America, reports on DP have been limited to sediment and fish, not known for birds, and regardless temporal trends in Great Lakes wildlife is unknown. In the present study, syn- and anti-DP isomers were detected in egg pools spanning 1982-2006 of a Great Lakes biomonitoring species, the herring gull (Larus argentatus), from seven colonies in the five Laurentian Great Lakes. The sum (Sigma) of syn- and anti-DP concentrations were generally <15 ng g(-1) wet weight (ww) and variable depending on the colonial site and year, although Sigma-DP concentrations were generally higher post mid-1990s for all sites. Syn- and anti-DP concentrations ranged from 3.1 x 10(2) to 1.4 x 10(3)pg g(-1)ww and 1.3 x 10(2) to 4.4 x 10(3)pg g(-1)ww, respectively. There was a weak but significant (r(S)=-0.31, p<0.001) negative relationship between the Sigma-DP concentration and the distance for the only DP production facility in North America at Niagara Falls, New York. However, the fraction of the anti-DP to the Sigma-DP concentration (f(anti)) was 0.69+/-0.08 (for all seven colonies and years, n=101 pools), and there was no significant (r(S)=-0.18, p=0.07) negative relationship of f(anti) with increasing distance from the production facility at Niagara Falls, New York, which indicated that there was no temporal or spatial enrichment of either isomer relative to the commercial DP mixture. Over the past 25 years, it is clear that DP isomers have accumulated in the food web of female herring gulls with subsequent transfer during ovogenesis.

  7. Increased Wounding of Southern Right Whale (Eubalaena australis) Calves by Kelp Gulls (Larus dominicanus) at Península Valdés, Argentina.

    PubMed

    Marón, Carina F; Beltramino, Lucas; Di Martino, Matías; Chirife, Andrea; Seger, Jon; Uhart, Marcela; Sironi, Mariano; Rowntree, Victoria J

    2015-01-01

    At least 626 southern right whale (Eubalaena australis) calves died at the Península Valdés calving ground, Argentina, between 2003 and 2014. Intense gull harassment may have contributed to these deaths. In the 1970s, Kelp Gulls (Larus dominicanus) began feeding on skin and blubber pecked from the backs of living right whales at Valdés. The frequency of gull attacks has increased dramatically over the last three decades and mother-calf pairs are the primary targets. Pairs attacked by gulls spend less time nursing, resting and playing than pairs not under attack. In successive attacks, gulls open new lesions on the whales' backs or enlarge preexisting ones. Increased wounding could potentially lead to dehydration, impaired thermoregulation, and energy loss to wound healing. The presence, number and total area of gull-inflicted lesions were assessed using aerial survey photographs of living mother-calf pairs in 1974-2011 (n = 2680) and stranding photographs of dead calves (n = 192) in 2003-2011. The percentage of living mothers and calves with gull lesions increased from an average of 2% in the 1970s to 99% in the 2000s. In the 1980s and 1990s, mothers and calves had roughly equal numbers of lesions (one to five), but by the 2000s, calves had more lesions (nine or more) covering a greater area of their backs compared to their mothers. Living mother-calf pairs and dead calves in Golfo Nuevo had more lesions than those in Golfo San José in the 2000s. The number and area of lesions increased with calf age during the calving season. Intensified Kelp Gull harassment at Península Valdés could be compromising calf health and thereby contributing to the high average rate of calf mortality observed in recent years, but it cannot explain the large year-to-year variance in calf deaths since 2000.

  8. [A comparative analysis of the helminth fauna of kittiwake Rissa tridactyla (Linnaeus, 1758) and glaucous gull Larus hyperboreus Gunnerus, 1767 from different parts of the Barents Sea].

    PubMed

    Kuklin, V V; Galaktionov, K V; Galkin, A K; Marasaev, S F

    2005-01-01

    The article is based on the results of helminthological observations made on kittiwake Rissa tridactyla and glaucous gull Larus hyperboreus in 1991-2001 in different areas of the Barents Sea (Eastern Murman coast, Franz Josef Land, Novaya Zemlya, Spitzbergen). 18 helminth species (2 trematodes, 11 cestodes, 4 nematodes, and 2 acanthocephalans) were recorded in the kittiwakes and 19 (3 trematodes, 9 cestodes, 5 nematodes and 2 acanthocephalans) species were recorded in the glaucous gulls. Trematodes were absent in the birds collected at the Franz Josef Land and the northern island of Novaya Zemlya. 3 trematode species, namely Gymnophallus sp. (somateria?), Microphallus sp. 1 (M. pseudopygmaeus), and Cryptocotyle lingua were found in the glaucous gulls of western Spitzbergen. It was supposed that the life cycles of these parasites can be completed there. On the other hand, coastal ecosystems of Arctic archipelagoes turn out to be favourable for the transmission of some cestodes. This is closely connected with the regional traits in the marine bird diet, namely the increase of the amphipod (intermediate hosts of hymenolepidids and some dilepidids) and polar cod (supposed second intermediate host for some tetrabothriids) portion in Arctic. As a result, cestodes are the base of the helminth fauna of kittiwakes and glaucous gulls of the Barents Sea, by their species richness, prevalence and abundance. Nematodes and acanthocephalans were represented by a few species with low infection intensity. The main ecological factors affected the regional difference in the species richness and abundance of the helminths parasitising kittiwakes and glaucous gulls in the Barents Sea are proposed. Those are regional climatic features and regional traits in the behaviour and food priorities of birds, and also the distribution of the helminths intermediate hosts, invertebrates and fishes. The phenomenon of host specificity lowering with respect to the definitive host was recorded in some

  9. The Glaucous-Winged Gull (Larus glaucescens) as an Indicator of Chemical Contaminants in the Canadian Pacific Marine Environment: Evidence from Stable Isotopes.

    PubMed

    Davis, M L; Elliott, J E; Williams, T D

    2017-08-01

    The Glaucous-winged gull (Larus glaucescens) has been selected by Environment Canada as a marine indicator species for long-term monitoring of persistent contaminants in the Canadian Pacific. However, the indicator value of this species depends on its trophic level and proportion of marine prey in its diet. Eggs, used as the monitoring medium, are produced entirely from maternal resources and knowledge of adult diet before and during egg production is critical to interpreting contaminant levels. Due to a lack of recent and reliable dietary ecology work, we examined the diet of breeding Glaucous-winged gulls through carbon (δ(13)C) and nitrogen (δ(15)N) stable isotope analysis at three colonies on the Pacific coast. Near-shore marine prey, occupying a high trophic level (δ(15)N), composed a predominant component of all Glaucous-winged gull diet. Adult diet composition from colonies in the Salish Sea was more varied than the west coast of Vancouver Island, reflecting the opportunistic foraging nature of this species in areas where the abundance of marine prey is known to fluctuate. Compared with incubating adults, pre-laying adults had a significantly lower trophic level that may reflect the need to consume marine invertebrates to acquire specific nutrients necessary for egg production. Interannual variation in both trophic level and prey source (δ(13)C) in egg and chick tissues indicates the need to pair ongoing contaminant monitoring with stable isotope analysis. The predominantly marine diet and relatively high trophic level of this gull supports its use as an indicator of marine pollution on the Pacific coast.

  10. Increased Wounding of Southern Right Whale (Eubalaena australis) Calves by Kelp Gulls (Larus dominicanus) at Península Valdés, Argentina

    PubMed Central

    Marón, Carina F.; Beltramino, Lucas; Di Martino, Matías; Chirife, Andrea; Seger, Jon; Uhart, Marcela; Sironi, Mariano; Rowntree, Victoria J.

    2015-01-01

    At least 626 southern right whale (Eubalaena australis) calves died at the Península Valdés calving ground, Argentina, between 2003 and 2014. Intense gull harassment may have contributed to these deaths. In the 1970s, Kelp Gulls (Larus dominicanus) began feeding on skin and blubber pecked from the backs of living right whales at Valdés. The frequency of gull attacks has increased dramatically over the last three decades and mother-calf pairs are the primary targets. Pairs attacked by gulls spend less time nursing, resting and playing than pairs not under attack. In successive attacks, gulls open new lesions on the whales’ backs or enlarge preexisting ones. Increased wounding could potentially lead to dehydration, impaired thermoregulation, and energy loss to wound healing. The presence, number and total area of gull-inflicted lesions were assessed using aerial survey photographs of living mother-calf pairs in 1974–2011 (n = 2680) and stranding photographs of dead calves (n = 192) in 2003–2011. The percentage of living mothers and calves with gull lesions increased from an average of 2% in the 1970s to 99% in the 2000s. In the 1980s and 1990s, mothers and calves had roughly equal numbers of lesions (one to five), but by the 2000s, calves had more lesions (nine or more) covering a greater area of their backs compared to their mothers. Living mother-calf pairs and dead calves in Golfo Nuevo had more lesions than those in Golfo San José in the 2000s. The number and area of lesions increased with calf age during the calving season. Intensified Kelp Gull harassment at Península Valdés could be compromising calf health and thereby contributing to the high average rate of calf mortality observed in recent years, but it cannot explain the large year-to-year variance in calf deaths since 2000. PMID:26488493

  11. The influence of predation by herring gulls Larus argentatus and oystercatchers Haematopus ostralegus on a newly established mussel Mytilus edulis bed in autumn and winter

    NASA Astrophysics Data System (ADS)

    Hilgerloh, G.; Herlyn, M.; Michaelis, H.

    1997-08-01

    Predation by herring gulls Larus argentatus and oystercatchers Haematopus ostralegus was evaluated on a newly established mussel Mytilus edulis bed on tidal flats of the German Wadden Sea. The mussel bed covered an area of 2 ha and showed a decrease in biomass of 40% in the most densely covered parts from August to January. Synchronously, the extent of the mussel bed was reduced, resulting in a decrease of average biomass of 98% over the whole mussel bed. From the beginning of August 1994 to mid January 1995, the average size of mussels increased from 10.7 to 20.3 mm. The P/B-ratio was 0.68 in August and 0.18 between September and November. Herring gulls and oystercatchers were the most important mussel predators. On average, 266 herring gulls and 63 oystercatchers were present on the mussel bed during one low tide; 34% of the herring gulls and 78% of the oystercatchers were observed to be feeding. Herring gulls fed at a rate of 4.2 mussels per minute and oystercatchers at a rate of 1.3 mussels per minute. While herring gulls took the most common mussel sizes (mean: 20 mm), oystercatchers searched for the largest mussels available (mean: 25 mm). Herring gulls consumed 13 mussels/m2 (0.3g AFDW) during one day and oystercatchers 1.7 mussels/m2 (0.1 g AFDW). Predation by birds was compensated by 33% of the production. The proportion removed by bird predation amounted to 10% of abundance and to 16% of biomass (including production). Oystercatchers were responsible for 1% of the reduction in abundance and for 3% of biomass. Removal was highest in the most common size classes of mussels, mainly caused by herring gulls. However, the highest proportion of mussels was eaten in the largest size classes, mainly by oystercatchers. *** DIRECT SUPPORT *** A03B6035 00004

  12. Maternal effects mediated by egg quality in the Yellow-legged Gull Larus michahellis in relation to laying order and embryo sex

    PubMed Central

    2011-01-01

    Background Maternal effects mediated by egg size and quality may profoundly affect offspring development and performance, and mothers may adjust egg traits according to environmental or social influences. In avian species, context-dependency of maternal effects may result in variation in egg composition, as well as in differential patterns of covariation among selected egg components, according to, for example, position in the laying sequence or offspring sex. We investigated variation in major classes of egg yolk components (carotenoids, vitamins and steroid hormones) in relation to egg size, position in the laying sequence and embryo sex in clutches of the Yellow-legged Gull (Larus michahellis). We also investigated their covariation, to highlight mutual adjustments, maternal constraints or trade-offs in egg allocation. Results Laying sequence-specific patterns of allocation emerged: concentration of carotenoids and vitamin E decreased, while concentrations of androgens increased. Vitamin A, estradiol and corticosterone did not show any change. There was no evidence of sex-specific allocation or covariation of yolk components. Concentrations of carotenoids and vitamins were positively correlated. Egg mass decreased along the laying sequence, and this decrease was negatively correlated with the mean concentrations of carotenoids in clutches, suggesting that nutritionally constrained females lay low quality clutches in terms of carotenoid content. Finally, clutches with smaller decline in antioxidants between first- and last-laid eggs had a larger increase in yolk corticosterone, suggesting that a smaller antioxidant depletion along the laying sequence may entail a cost for laying females in terms of increased stress levels. Conclusions Since some of the analyzed yolk components (e.g. testosterone and lutein) are known to exert sex-specific phenotypic effects on the progeny in this species, the lack of sex-specific egg allocation by mothers may either result from

  13. Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment.

    PubMed

    Marteinson, Sarah C; Giroux, Jean-François; Hélie, Jean-François; Gentes, Marie-Line; Verreault, Jonathan

    2015-01-01

    Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in

  14. Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment

    PubMed Central

    Marteinson, Sarah C.; Giroux, Jean-François; Hélie, Jean-François; Gentes, Marie-Line; Verreault, Jonathan

    2015-01-01

    Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in

  15. Reassortment of American and Eurasian genes in an influenza A virus isolated from a great black-backed gull (Larus marinus), a species demonstrated to move between these regions.

    PubMed

    Wille, Michelle; Robertson, Gregory J; Whitney, Hugh; Ojkic, Davor; Lang, Andrew S

    2011-01-01

    The primary hosts for influenza A viruses are waterfowl, although gulls and shorebirds are also important in global avian influenza dynamics. Avian influenza virus genes are separated phylogenetically into two geographic clades, American and Eurasian, which is caused by the geographic separation of the host species between these two regions. We surveyed a gregarious and cosmopolitan species, the Great Black-backed Gull (Larus marinus), in Newfoundland, Canada, for the presence of avian influenza viruses. We have isolated and determined the complete genome sequence of an H13N2 virus, A/Great Black-backed Gull/Newfoundland/296/2008(H13N2), from one of these birds. Phylogenetic analysis revealed that this virus contained two genes in the American gull clade (PB1, HA), two genes in the American avian clade (PA, NA), and four genes in the Eurasian gull clade (PB2, NP, M, NS). We analyzed bird band recovery information and found the first evidence of trans-Atlantic migration from Newfoundland to Europe (UK, Spain and Portugal) for this species. Thus, great black-backed gulls could be important for movement of avian influenza viruses across the Atlantic Ocean and within North America.

  16. Brain cholinesterase reactivation as a marker of exposure to anticholinesterase pesticides: a case study in a population of yellow-legged gull Larus michahellis (Naumann, 1840) along the northern coast of Portugal.

    PubMed

    Santos, Cátia S A; Monteiro, Marta S; Soares, Amadeu M V M; Loureiro, Susana

    2016-01-01

    Between late 2010 to early 2011, an increased mortality in gulls was observed along the northern coast of Portugal, with individuals exhibiting neurologic disorders consistent with an eventual anticholinesterase pesticide poisoning event. To clarify if this mortality was related to organophosphate (OP) and/or carbamate (CB) poisoning, chemical and spontaneous cholinesterase (ChE) reactivation was tested in the brain of the yellow-legged gull (Larus michahellis). Initial brain ChE activity in L. michahellis was 40.92 ± 5.23 U/mg of protein (average ± SE). Following chemical and spontaneous reactivation, ChE activity increased in average 70.38 ± 48.59% and 131.95 ± 92.64%, respectively. ChE reactivation was found to decrease at increasing concentrations of the oxime pyridine-2-aldoxime methochloride and dilution factor, underscoring the importance of first optimizing the assay conditions prior to its use on bird species. These results suggest that birds analysed could have been exposed to OP and CB pesticide compounds and that in most cases CB exposure appeared to be the main cause of birds poisoning. These results are an important contribution to environmental monitoring as it demonstrates the suitability of L. michaellis as sentinel species of OP and CB pesticides within an urban environment.

  17. Phylogenetic Placement of a Schistosome from an Unusual Marine Snail Host, the False Limpet (Siphonaria lessoni) and Gulls (Larus dominicanus) from Argentina with a Brief Review of Marine Schistosomes from Snails.

    PubMed

    Brant, Sara V; Loker, Eric S; Casalins, Laura; Flores, Veronica

    2017-02-01

    In the blood fluke family Schistosomatidae, marine snails are well known as intermediate hosts. Eight families of marine snails have thus far been reported to host schistosomes across the world, most of which have been implicated in human cercarial dermatitis (HCD) outbreaks. As part of our larger effort to define the species diversity and biology of schistosomes in Argentina, in particular their role in causing HCD, we searched in the marine pulmonate snail (Siphonaria lessoni) for a schistosome species described previously from S. lessoni from southern Argentina. Additionally, gulls (Larus dominicanus) collected from a different project locality (inland) were examined, because they are known to spend time in the intertidal regions. Schistosome sporocysts were found in S. lessoni, and a small worm fragment was retrieved from a gull. Molecular phylogenies for 28S, ITS1-5.8S-ITS2, and cox1 genes revealed that the specimens from the gull and S. lessoni grouped closely together, suggesting they are conspecifics. Also, ITS1-5.8S-ITS2 sequences suggested one of the schistosomes from S. lessoni and a schistosome from a South African penguin were also conspecifics. Further study is needed to verify if these specimens comprise a distinct marine clade within the larger avian schistosome clade that is comprised mostly of species using freshwater snail hosts. Thus far, it appears this group of marine schistosomes may be more likely found in the southern hemisphere. It is unclear if the observed distribution pattern of schistosomes in Siphonaria is a result of sampling bias and/or indicative of a specific bird-snail-schistosome association. It is clear they are sharply differentiated from the basal marine clade of avian schistosomes that includes Austrobilharzia.

  18. Temporal and geographic variation of organochlorine residues in eggs of the common snapping turtle (Chelydra serpentina serpentina) (1981-1991) and comparisons to trends in the herring gull (Larus argentatus) in the Great Lakes basin in Ontario, Canada.

    PubMed

    Bishop, C A; Ng, P; Norstrom, R J; Brooks, R J; Pettit, K E

    1996-11-01

    Common snapping turtle (Chelydra serpentina serpentina) eggs from five sites within the Great Lakes basin, and from a reference site in north-central Ontario were collected during 1981-1991 and analyzed for four organochlorine pesticides, polychlorinated biphenyls (PCBs) including six non-ortho PCBs, polychlorinated dibenzodioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). The pattern of geographic variation was consistent over time in eggs with Cootes Paradise/ Hamilton Harbour and Lynde Creek eggs on Lake Ontario containing the highest concentrations and most PCDD and PCDF congeners among all sites. Eggs from Cranberry Marsh on Lake Ontario contained organochlorine concentrations similar to those from Big Creek Marsh and Rondeau Provincial Park on Lake Erie except PCDDs and PCDFs which occurred at higher concentrations and more congeners were detectable in Cranberry Marsh eggs. Concentrations of most contaminants in turtle eggs from Algonquin Park, the reference site, have significantly decreased in the past decade. Dieldrin concentrations, however, increased in Algonquin Park eggs from 1981 to 1989. Significant decreases in concentrations of hexachlorobenzene, mirex and PCBs occurred between turtle eggs collected in 1981/84 and 1989 at Big Creek Marsh and Rondeau Provincial Park, whereas there was no significant change in concentrations of p,p'-DDE and dieldrin. In Lake Ontario eggs, concentrations of PCBs, p,p'-DDE and dieldrin increased significantly between 1984 and 1991. Differences were also found in patterns of temporal variation in contamination between herring gulls (Larus argentatus) and snapping turtles which were attributed to differences in diet. Elevated and continued contamination in turtle eggs from Lake. Ontario is probably due to a combination of local sources of chemicals and consumption of large migratory fish that spawn in wetlands inhabited by these turtles.

  19. Influence of trophic ecology on the accumulation of dioxins and furans (PCDD/Fs), non-ortho polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in Mediterranean gulls (Larus michahellis and L. audouinii): A three-isotope approach.

    PubMed

    Roscales, Jose L; Vicente, Alba; Muñoz-Arnanz, Juan; Morales, Laura; Abad, Esteban; Aguirre, Jose I; Jiménez, Begoña

    2016-05-01

    The impact of pollution caused by severe anthropogenic pressure in the Mediterranean Sea, an important biodiversity hotspot, requires continuous research efforts. Sources of highly toxic chemicals such as Persistent Organic Pollutants (POPs) are misunderstood in representative Mediterranean species, which limits our capability to establish proper conservation strategies. In the present study, eggs of Audouin's and yellow-legged gulls (Larus audouinii and L. michahellis) were used to investigate the trophic sources, as measured by δ(13)C, δ(15)N, and δ(34)S, of legacy POPs, in particular, polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and non-ortho polychlorinated biphenyls (no-PCBs), as well as recently-regulated POPs, e.g., polybrominated diphenyl ethers (PBDEs). Special attention was paid to the usefulness of rarely-explored δ(34)S ratios in explaining POP exposure in wildlife, and δ(34)S was the isotopic ratio that best explained POP variations among gulls in most cases, thus demonstrating its usefulness for understanding POP exposure in wildlife. Significant relationships between stable isotope signatures and POP concentrations revealed increasing levels of no-PCBs and low halogenated PCDD/Fs and PBDEs in Mediterranean gulls as the consumption of marine resources increases. In contrast, highly chlorinated and brominated congeners appeared to preferentially accumulate in gulls feeding primarily on refuse from dump sites and terrestrial food webs. The use of suitable dietary tracers in the study of POPs in yellow-legged gulls revealed the importance of dump sites as a source of POPs in Mediterranean seabirds, which has not previously been reported. In contrast, the preferential accumulation through marine food webs of low chlorinated PCCD/Fs and no-PCBs, which show the highest toxic equivalents factors (TEFs), led to a significantly greater toxicological concern in Audouin's as compared to yellow-legged gulls. Audouin's gull exposure to POPs appears

  20. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2009-05-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles.

  1. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska

    PubMed Central

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles. PMID:18521716

  2. Capillarity and fibre types in locomotory muscles of wild yellow-legged gulls (Larus cachinnans).

    PubMed

    Torrella, J R; Fouces, V; Palomeque, J; Viscor, G

    1998-01-01

    This study analyzes the capillarity and fibre-type distribution of six locomotory muscles of gulls. The morphological basis and the oxygen supply characteristics of the skeletal muscle of a species with a marked pattern of gliding flight are established, thus contributing to a better understanding of the physiology of a kind of flight with low energetic requirements. The four wing muscles studied (scapulotriceps, pectoralis, scapulohumeralis, and extensor metacarpi) exhibited higher percentages of fast oxidative glycolytic fibres (>70%) and lower percentages of slow oxidative fibres (<16%) than the muscles involved in nonflight locomotion (gastrocnemius and iliotibialis). Capillary densities ranged from 816 to 1,233 capillaries mm(-2), having the highest value in the pectoralis. In this muscle, the fast oxidative glycolytic fibres had moderate staining for succinate dehydrogenase and relatively large fibre sizes, as deduced from the low fibre densities (589-665 fibres mm(-2)). All these findings are seen as an adaptive response for gliding, when the wing is held outstretched by isometric contractions. The leg muscles studied included a considerable population of slow oxidative fibres (>14% in many regions), which suggests that they are adapted to postural activities. Regional variations in the relative distributions of fibre types in muscle gastrocnemius may reflect different functional demands placed on this muscle during terrestrial and aquatic locomotion. The predominance of oxidative fibres and capillary densities under 1,000 capillaries mm(-2) in leg muscles is probably a consequence of an adaptation for slow swimming and maintenance of the posture on land rather than for other locomotory capabilities, such as endurance or sprint activities.

  3. Modelling terrestrial and marine foraging habitats in breeding Audouin's gulls Larus audouinii: timing matters.

    PubMed

    Bécares, Juan; García-Tarrasón, Manuel; Villero, Dani; Bateman, Santiago; Jover, Lluís; García-Matarranz, Víctor; Sanpera, Carolina; Arcos, José Manuel

    2015-01-01

    Although the breeding ecology of Audouin's gull has been widely studied, its spatial distribution patterns have received little attention. We assessed the foraging movements of 36 GPS-tracked adult Audouin's gulls breeding at the Ebro Delta (NW Mediterranean), coinciding with the incubation period (May 2011). This also coincided with a trawling moratorium northwards from the colony. We modelled the distribution of the gulls by combining these tracking data with environmental variables (including fishing activities from Vessel Monitoring System, VMS), using Maxent. The modelling range included both marine and terrestrial areas. Models were produced separately for every 2h time interval across the day, and for 2 fishing activity scenarios (workdays vs. weekends), allowing to assess the spatio-temporal distribution patterns of the gulls and the degree of association with fisheries. During workdays, gull distribution at sea fully matched with fishing activities, both trawling (daylight) and purse-seining (nightime). Gulls tended to avoid the area under trawling moratorium, confirming the high influence of fisheries on the distribution patterns of this species. On weekends, gulls made lesser use of the sea and tended to increase the use of rice fields. Overall, Audouin's gull activity was more intense during dailight hours, although birds also showed nocturnal activity, on both workdays and weekends. Nocturnal patterns at sea were more disperse during the latter, probably because these gulls are able to capture small pelagic fish at night in natural conditions, but tend to congregate around purse-seiners (which would enhance their foraging efficiency) in workdays. These results provide important insight for the management of this species. This is of particular relevance under the current scenario of European fisheries policies, since new regulations are aimed at eliminating discards, and this would likely influence Audouin's gull populations.

  4. Insects, vegetation, and the control of laughing gulls (Larus atricilla) at Kennedy International Airport, New York

    USGS Publications Warehouse

    Buckley, P.A.; McCarthy, M.

    1994-01-01

    1. In response to a purported 'bird-strike problem' at J.F. Kennedy International Airport in New York City, we examined short (5 cm) and long (45 cm) grass heights as gull deterrents, in a randomized-block experiment. 2. Vegetative cover, numbers of adult insects and of larval beetles (suspected on-airport food of the gulls) were sampled in the six-block, 36-plot study area, as well as gut contents of adult and downy young gulls in the immediately adjacent colony in the Jamaica Bay Wildlife Refuge. 3. We found that (i) Oriental beetle larvae were the most numerous and concentrated in one experimental block; (ii) beetle larvae numbers were uncorrelated with grass height; (iii) adult beetles were also uncorrelated with grass height; (iv) laughing gulls were distributed across blocks irrespective of percentage cover; (v) within blocks, laughing gulls were selecting short grass and avoiding long grass plots; (vi) laughing gull numbers were positively associated with numbers of Oriental beetle larvae; (vii) adult laughing gulls on the airport were eating lower-nutrition food of terrestrial origin (74-83% adult beetles, mostly Oriental plus green June and ground beetles); (viii) on the other hand, gull chicks in the adjacent breeding colony were being fed more easily digested, higher-protein food of marine origin (86-88% fishes, crustacea and molluscs); (ix) laughing gulls on the airport were taking their adult beetles only in short-grass plots, ignoring large numbers in adjacent long grass; (x) during the summer, on-airport gulls shifted from performing largely maintenance activities on pavement to feeding actively for beetles on newly mown short grass, the change coinciding with adult beetle emergence; (xi) standing water on the airport attracted significantly more gulls than dry areas all summer long. 4. We recommend a series of ecologically compatible, but aggressive habitat management actions for controlling laughing gulls on Kennedy Airport by rendering the airport unattractive to them, notably by implementing an airport-wide programme of long-grass encouragement, draining standing water and improving runoff in water-collecting areas, and controlling beetles. 5. We conclude by outlining the necessity for airport-wide bird, vegetation and habitat management programmes fully integrated into airport operation and planning activities.

  5. Genetic variability in mitochondrial and nuclear genes of Larus dominicanus (Charadriiformes, Laridae) from the Brazilian coast

    PubMed Central

    de Mendonça Dantas, Gisele Pires; Meyer, Diogo; Godinho, Raquel; Ferrand, Nuno; Morgante, João Stenghel

    2012-01-01

    Several phylogeographic studies of seabirds have documented low genetic diversity that has been attributed to bottleneck events or individual capacity for dispersal. Few studies have been done in seabirds on the Brazilian coast and all have shown low genetic differentiation on a wide geographic scale. The Kelp Gull is a common species with a wide distribution in the Southern Hemisphere. In this study, we used mitochondrial and nuclear markers to examine the genetic variability of Kelp Gull populations on the Brazilian coast and compared this variability with that of sub-Antarctic island populations of this species. Kelp Gulls showed extremely low genetic variability for mitochondrial markers (cytb and ATPase) and high diversity for a nuclear locus (intron 7 of the β-fibrinogen). The intraspecific evolutionary history of Kelp Gulls showed that the variability found in intron 7 of the β-fibrinogen gene was compatible with the variability expected under neutral evolution but suggested an increase in population size during the last 10,000 years. However, none of the markers revealed evidence of a bottleneck population. These findings indicate that the recent origin of Kelp Gulls is the main explanation for their nuclear diversity, although selective pressure on the mtDNA of this species cannot be discarded. PMID:23271950

  6. Modelling Terrestrial and Marine Foraging Habitats in Breeding Audouin's Gulls Larus audouinii: Timing Matters

    PubMed Central

    Bécares, Juan; García-Tarrasón, Manuel; Villero, Dani; Bateman, Santiago; Jover, Lluís; García-Matarranz, Víctor; Sanpera, Carolina; Arcos, José Manuel

    2015-01-01

    Although the breeding ecology of Audouin’s gull has been widely studied, its spatial distribution patterns have received little attention. We assessed the foraging movements of 36 GPS-tracked adult Audouin’s gulls breeding at the Ebro Delta (NW Mediterranean), coinciding with the incubation period (May 2011). This also coincided with a trawling moratorium northwards from the colony. We modelled the distribution of the gulls by combining these tracking data with environmental variables (including fishing activities from Vessel Monitoring System, VMS), using Maxent. The modelling range included both marine and terrestrial areas. Models were produced separately for every 2h time interval across the day, and for 2 fishing activity scenarios (workdays vs. weekends), allowing to assess the spatio-temporal distribution patterns of the gulls and the degree of association with fisheries. During workdays, gull distribution at sea fully matched with fishing activities, both trawling (daylight) and purse-seining (nightime). Gulls tended to avoid the area under trawling moratorium, confirming the high influence of fisheries on the distribution patterns of this species. On weekends, gulls made lesser use of the sea and tended to increase the use of rice fields. Overall, Audouin’s gull activity was more intense during dailight hours, although birds also showed nocturnal activity, on both workdays and weekends. Nocturnal patterns at sea were more disperse during the latter, probably because these gulls are able to capture small pelagic fish at night in natural conditions, but tend to congregate around purse-seiners (which would enhance their foraging efficiency) in workdays. These results provide important insight for the management of this species. This is of particular relevance under the current scenario of European fisheries policies, since new regulations are aimed at eliminating discards, and this would likely influence Audouin’s gull populations. PMID:25875597

  7. Comparison of Trace Element Concentrations Between Chick and Adult Black-Tailed Gulls (Larus crassirostris).

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2015-06-01

    Trace elements were measured in the feathers of black-tailed gull chicks (n = 10) and adults (n = 10) collected at Chilsando Is., Jeollanam-do, Korea, in June 2011. Pb, Mn and Fe were significantly greater in adult (arithmetic mean 2.02, 3.81, 92.1 μg/g dw, respectively) than chick (0.74, 2.14, 68.7 μg/g dw) gulls. In contrast, Zn was greater in chicks (74.9 μg/g dw) than adults (46.5 μg/g dw). Cd, Pb and Cr in all chicks and adults were lower than an approximate threshold level for toxic effects. Cd, Pb and Cr were comparable or lower than reported in other gull studies worldwide. Essential elements including Al, Cu, Mn, Zn and Fe were within the background and normal physiological levels reported earlier in other gull species including black-tailed gulls.

  8. The complete mitogenome of the Black-tailed gull Larus crassirostris (Charadriiformes: Laridae).

    PubMed

    Kim, Ji Young; Park, Yung Chul

    2016-05-01

    The complete mitogenome (KM507782) of the Black-tailed gull L. crassirostris was 16,746 bp long, with A 30.6% (5128 bp), T 24.3% (4076 bp), C 30.9% (5176 bp), and G 14.1% (2366 bp). Total length of 13 protein-coding genes was 11,396 bp and 12 of them except for ND6 were encoded in heavy strand. The three initiation codons ATG, GTG and ATT were used in the protein-coding genes. The ATG was a common initiation codon which was found in most of the protein-coding genes, whereas GTG was used in COX1 and ND5 and ATT in only ND3, respectively. The total length of 22 tRNA genes was 1550 bp, ranging from 66 bp (tRNA(Ser(AGY))) to 74 bp (tRNA(Leu(UUR)) and tRNA(Ser(UCN))).

  9. Salmonella in Black-headed gulls ( Larus ridibundus); prevalence, genotypes and influence on Salmonella epidemiology.

    PubMed

    Palmgren, H; Aspán, A; Broman, T; Bengtsson, K; Blomquist, L; Bergström, S; Sellin, M; Wollin, R; Olsen, B

    2006-06-01

    During a period of 3 years, 1998-2000, 1047 faecal swabs from Black-headed gulls were sampled at one location in Southern Sweden. Salmonella spp. was found in 28 individuals (2.7%) and the dominating serotype found was S. Typhimurium (83%). Twenty-five per cent of the Salmonella-infected gulls were later recaptured and re-sampled. We found that Salmonella infection in Black-headed gulls was of short duration, and that infection in this bird species was predominantly expressed as carriage without disease manifestations. All S. Typhimurium isolates were subjected to antibiotic resistance profiling and molecular characterization by pulsed-field gel electrophoresis and IS200 polymerase chain reaction. The S. Typhimurium gull isolates were compared to human and domestic animal isolates of the same serotype and phage type. We found genetic relatedness of S. Typhimurium DT195 isolates from gulls, domestic animals and humans, indicating that Black-headed gulls might play a role in the spread of S. Typhimurium in Sweden.

  10. Head-bobbing and non-bobbing walking of black-headed gulls (Larus ridibundus).

    PubMed

    Fujita, Masaki

    2006-05-01

    Head-bobbing walking (HBW) and non-bobbing walking (NBW) of black-headed gulls were compared from kinematic and behavioral/environmental viewpoints. The birds walked with a longer stride length and lower stride frequency during the HBW than during the NBW. With respect to these two parameters, the HBW of black-headed gulls was similar to that of other head-bobbers, and the NBW was similar to that of other non-bobbers. The stride length and the amplitude of head bobbing were correlated. These results suggest that the head-bobbing and gait parameters are related. From a behavioral viewpoint, HBW was observed during seeking-type foraging by wading, and NBW was observed during waiting-type foraging on a flat substrate. The type of foraging behavior and/or substrate condition probably determines whether the birds walk with or without head bobbing.

  11. Relationships of metals between feathers and diets of black-tailed gull (Larus crassirostris) chicks.

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2014-03-01

    In birds, metal contaminants in feathers are influenced by prey concentrations and environmental quality. In Black-tailed Gull chicks, Cd, Pb and Cu concentrations were strongly correlated between feathers and stomach contents. Between feathers and livers, Pb, Zn and Fe concentrations were significantly correlated. Cd concentrations were within the range of other seabirds and within the background level for bird feathers (<2 μg/g dw). At the lighthouse, eight chicks exceeded the background for Pb level in feathers (>4 μg/g dw). Elevated Pb concentrations might be attributed to ingestion of paint-based chips and natural (soil and rocks) sources. There is evidence that the analyzed birds suffered from acute toxicity, including high levels of pecking from conspecifics and increased mortality from elevated Pb levels. It seems likely that these birds might experience negative health effects from this increased Pb exposure. As a result, Black-tailed Gull chick feathers are a very useful monitoring tool for assessing Cd, Pb and Cu contamination. Essential elements such as Fe, Zn, Mn and Cu were all within the acceptable range of normal concentrations for seabird species including gulls and may be maintained by normal homeostatic mechanisms.

  12. Molecular Detection of Campylobacter spp. in California Gull (Larus californicus) Excreta

    EPA Science Inventory

    We examined the prevalence, quantity, and diversity of Campylobacter species in the excreta of 159 California gull samples using PCR and qPCR based detection assays. While Campylobacter prevalence and abundance was relatively high in the gull excreta examined, molecular data ind...

  13. Changes in food web structure affect rate of PCB decline in herring gull (Larus argentatus) eggs

    SciTech Connect

    Hebert, C.E.; Hobson, K.A.; Shutt, J.L.

    2000-05-01

    Biological monitors provide important information regarding temporal trends in levels of persistent organic pollutants. Correct interpretation of these trends is critical if one is to accurately assess his progress in eliminating these contaminants from the environment. In the Laurentian Great Lakes, polychlorinated biphenyl concentrations in herring gull eggs declined during the 1970s and early 1980s. By the mid-1980s, further declines were not as obvious. An exception to this trend was observed in eggs from Lake Erie. On that lake, egg PCB concentrations continued to decline rapidly during the 1980s/1990s. Evidence from stable isotope analysis indicated that temporal changes in the composition of the herring gull diet occurred on Lake Erie. In the eastern basin, declines in fish availability may have forced the gulls to incorporate a greater proportion of terrestrial food into their diets. Decreases in the proportion of fish in the gull diet would have resulted in reduced PCB exposure. This may be partially responsible for the continuing rapid rate of decline in egg PCB concentrations. This decline should be interpreted with caution. These trends may not be indicative of lake-wide declines in PCB bioavailability but only reflect changes in dietary exposure brought about by alterations in food web structure.

  14. Molecular Detection of Campylobacter spp. in California Gull (Larus californicus) Excreta

    EPA Science Inventory

    We examined the prevalence, quantity, and diversity of Campylobacter species in the excreta of 159 California gull samples using PCR and qPCR based detection assays. While Campylobacter prevalence and abundance was relatively high in the gull excreta examined, molecular data ind...

  15. Mercury levels and health parameters in the threatened Olrog's Gull (Larus atlanticus) from Argentina.

    PubMed

    La Sala, Luciano Francisco; Petracci, Pablo Fabricio; Smits, Judit Emmy; Botté, Sandra; Furness, Robert W

    2011-10-01

    Mercury (Hg) exposure was investigated through feathers of Olrog's Gull and related to health parameters in adults (hematocrit, total plasma proteins, morphometric measures, sex) and chicks (hematocrit, total plasma proteins, immunoglobulins G and M) from a colony located in estuary of Bahía Blanca, Argentina. Mercury concentrations were 5.50 ± 2.59 μg g⁻¹ (n = 44) in live adults, 1.85 ± 0.45 μg g⁻¹ (n = 45) in live chicks and 1.81 ± 0.41 μg g⁻¹ (n = 41) in dead chicks. Large differences were observed between live adults and live or dead chicks and small differences between live and dead chicks. In the adults, the sex of the birds was the variable that best explained Hg concentrations. Male birds had higher concentrations than females; this suggests that the clutch provides a sink for mercury during egg laying. Hg concentrations in both adults and live chicks were associated with higher hematocrits. This could be associated with upregulated erythropoiesis to compensate for increased rate of destruction of prematurely senescent, Hg-contaminated erythrocytes. Based on our results, on the levels of Hg pollution in the past in the study area, and on the dietary specialization of Olrog's Gull, we must be vigilant about potential negative effects of Hg pollution on this population and recommend continued monitoring on this threatened species.

  16. Recurrent hybridization and recent origin obscure phylogenetic relationships within the ‘white-headed’ gull (Larus sp.) complex

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Wilson, Robert E.; Chesser, Terry; Pons, Jean-Marc; Crochet, Pierre-Andre; Driscoll, Amy; Dove, Carla

    2016-01-01

    Species complexes that have undergone recent radiations are often characterized by extensive allele sharing due to recent ancestry and (or) introgressive hybridization. This can result in discordant evolutionary histories of genes and heterogeneous genomes, making delineating species limits difficult. Here we examine the phylogenetic relationships among a complex group of birds, the white-headed gulls (Aves: Laridae), which offer a unique window into the speciation process due to their recent evolutionary history and propensity to hybridize. Relationships were examined among 17 species (61 populations) using a multilocus approach, including mitochondrial and nuclear intron DNA sequences and microsatellite genotype information. Analyses of microsatellite and intron data resulted in some species-based groupings, although most species were not represented by a single cluster. Considerable allele and haplotype sharing among white-headed gull species was observed; no locus contained a species-specific clade. Despite this, our multilocus approach provided better resolution among some species than previous studies. Interestingly, most clades appear to correspond to geographic locality: our BEAST analysis recovered strong support for a northern European/Icelandic clade, a southern European/Russian clade, and a western North American/canus clade, with weak evidence for a high latitude clade spanning North America and northwestern Europe. This geographical structuring is concordant with behavioral observations of pervasive hybridization in areas of secondary contact. The extent of allele and haplotype sharing indicates that ecological and sexual selection are likely not strong enough to complete reproductive isolation within several species in the white-headed gull complex. This suggests that just a few genes are driving the speciation process.

  17. [Reduction in variability of individual colonization programs in black-headed gulls (Larus ridibundus) leads to reproductive success diminishing].

    PubMed

    Druzyaka, V

    2015-01-01

    The problem of adaptive significance of territorial antagonism in colonial birds is addressed. Many of these birds are characterized, along with high tolerance to each other and tendency to aggregate, by intensive and variable territorial demonstrations. Here we consider the effects of territorial behavior on the viability of a breeding colony. We observed breeding of black-headed gull in two colonies formed under the impact of a short-term temperature fall in 2008, which resulted in the 7-day shift in timing of egg laying. Compared with the colonies at the same places, one in 2007 and one in 2009, in 2008 the number of nests and their density were rather smaller, whereas the duration of settling, the nest density increase and the average size of breeding territories have not changed. Average body weight of adult birds during incubation was stable through all the years. However, correlations, typical for 2007 and 2009 (negative between female mass and date of.clutch starting, and positive between masses of parents), were absent, suggesting that assortative mating by body mass and territory size was not the case in 2008. Average clutch, egg, and hatchling sizes were smaller in 2008 while mortality due to aerial predators was higher than in normal years. In 2007 and 2009, birds who started egg laying in the first 5 days after the first egg appeared in the colony (settlers) were larger than others (so-called followers) and produced larger offspring. These differences were not observed in 2008. According to our data, after the impact of cold weather, some birds abandoned their nesting sites, others were sick but mostly behaved as settlers and formed underpopulated and sparse colonies. We assume that the formation of a viable colony requires interaction of highly territorial 'pioneers' and a certain number of less competitive individuals. Withdrawal of the latter results into a general reproductive failure of the colony. Thus, the pattern of colony forma- tion as in the black-headed gull turns natural selection towards maintenance of the variety of individual programs of territorial competition.

  18. Recurrent hybridization and recent origin obscure phylogenetic relationships within the 'white-headed' gull (Larus sp.) complex.

    PubMed

    Sonsthagen, Sarah A; Wilson, Robert E; Chesser, R Terry; Pons, Jean-Marc; Crochet, Pierre-Andre; Driskell, Amy; Dove, Carla

    2016-10-01

    Species complexes that have undergone recent radiations are often characterized by extensive allele sharing due to recent ancestry and (or) introgressive hybridization. This can result in discordant evolutionary histories of genes and heterogeneous genomes, making delineating species limits difficult. Here we examine the phylogenetic relationships among a complex group of birds, the white-headed gulls (Aves: Laridae), which offer a unique window into the speciation process due to their recent evolutionary history and propensity to hybridize. Relationships were examined among 17 species (61 populations) using a multilocus approach, including mitochondrial and nuclear intron DNA sequences and microsatellite genotype information. Analyses of microsatellite and intron data resulted in some species-based groupings, although most species were not represented by a single cluster. Considerable allele and haplotype sharing among white-headed gull species was observed; no locus contained a species-specific clade. Despite this, our multilocus approach provided better resolution among some species than previous studies. Interestingly, most clades appear to correspond to geographic locality: our BEAST analysis recovered strong support for a northern European/Icelandic clade, a southern European/Russian clade, and a western North American/canus clade, with weak evidence for a high latitude clade spanning North America and northwestern Europe. This geographical structuring is concordant with behavioral observations of pervasive hybridization in areas of secondary contact. The extent of allele and haplotype sharing indicates that ecological and sexual selection are likely not strong enough to complete reproductive isolation within several species in the white-headed gull complex. This suggests that just a few genes are driving the speciation process. Published by Elsevier Inc.

  19. Molecular characterization of antibiotic resistance in enterococci recovered from seagulls (Larus cachinnans) representing an environmental health problem.

    PubMed

    Radhouani, Hajer; Igrejas, Gilberto; Pinto, Luís; Gonçalves, Alexandre; Coelho, Céline; Rodrigues, Jorge; Poeta, Patrícia

    2011-08-01

    Antimicrobial resistance and the mechanisms implicated were studied in 54 enterococci recovered from 57 seagull fecal samples. Almost 78% of the recovered enterococci showed resistance against one or more antibiotics and these isolates were identified to the species level. E. faecium was the most prevalent species (52.4%). High percentages of erythromycin and tetracycline resistances were found among our isolates (95.2%), and lower percentages were identified to other antibiotics. Most of the tetracycline-resistant strains carried the tet(M) and/or tet(L) genes. Genes associated with Tn916/Tn1545 and/or Tn5397 transposons were detected in 45% of tetracycline-resistant isolates. The erm(B) gene was detected in 65% of erythromycin-resistant isolates. The vat(D) and vat(E) genes were present in 5.9% and 11.8% of quinupristin/dalfopristin-resistant isolates, respectively. The ant(6)-Ia gene was identified in 57.1% of streptomycin-resistant isolates. All nine kanamycin-resistant isolates carried the aph(3)'-IIIa gene. The cat(A) gene was found in two chloramphenicol-resistant isolates. Seagulls should be considered a risk species for spreading in the environment antimicrobial resistant enterococci and can serve as a sentinel for antibiotic pressure from the surrounding farm and urban setting.

  20. Occurrence and numbers of bacteriophages and bacterial indicators in faeces of yellow-legged seagull (Larus cachinnans).

    PubMed

    Muniesa, M; Jofre, J; Lucena, F

    1999-12-01

    Faeces from feral populations of yellow-legged seagulls from the northern coastal area of Catalonia (North-eastern Spain) contained variable amounts of faecal coliforms, faecal streptococci, somatic coliphages, F-specific bacteriophages and Bacteroides fragilis bacteriophages. Occurrence and numbers of bacterial indicators and bacteriophages in the faeces of yellow-legged seagulls are in the ranges described in the faeces of different animals. The ratios between numbers of bacterial indicators and numbers of bacteriophages are much higher in faeces of seagulls than in treated or raw sewage contributed by out-falls of the same area.

  1. Far Away from the Revolution: Understanding the Cuban Revolutionary Armed Forces Mission Changes

    DTIC Science & Technology

    2011-12-01

    Youth Labor Army) FAR Fuerzas Armadas Revolucionarias (Revolutionary Armed Forces) GAESA Grupo de Administracion Empresarial S.A. (Enterprise...tourism were organized under the Grupo de Administracion Empresarial (GAESA) with the name of Gaviota Tourism Group. Gaviota operates and controls the

  2. High levels of perfluoroalkyl acids in eggs and embryo livers of great cormorant (Phalacrocorax carbo sinensis) and herring gull (Larus argentatus) from Lake Vänern, Sweden.

    PubMed

    Nordén, Marcus; Berger, Urs; Engwall, Magnus

    2013-11-01

    In the eggs and developing chick livers in the two wild bird species, great cormorant and herring gull, the concentrations of a range of 15 perfluoroalkyl acids (PFAAs) were determined. Eggs of the two species were collected from Lake Vänern, Sweden, and analysed either as undeveloped egg (whole egg or separated into yolk and albumen) or incubated until start of the hatching process when the chick liver was removed and analysed. High levels of PFAAs were found in all matrixes except albumen. The predominant PFAA was perfluorooctane sulfonate (PFOS), which was found in the μg/g wet weight (ww) range in some samples of cormorant whole egg, yolk and liver and herring gull egg yolk and liver. The average concentration in yolk was 1,506 ng/g ww in cormorant and 589 ng/g ww in herring gull. The average liver concentrations of PFOS were 583 ng/g ww in cormorant and 508 ng/g ww in herring gull. At these concentrations, biochemical effects in the developing embryo or effects on embryo survival cannot be ruled out. For perfluoroalkyl carboxylates (PFCAs), the liver/egg and liver/yolk concentration ratios increased with PFCA chain length in cormorant but not in herring gull, indicating that chain length could possibly affect egg-to-liver transfer of PFCAs and that species differences may exist.

  3. Lesser black-backed gulls (Larus fuscus) consuming swimming crabs: An important link in the food web of the southern North Sea

    NASA Astrophysics Data System (ADS)

    Schwemmer, Henriette; Schwemmer, Philipp; Ehrich, Siegfried; Garthe, Stefan

    2013-03-01

    Swimming crabs (Liocarcinus spp.) are one of the most common brachyuran species in the North Sea, and their abundance has substantially increased over the last century. Seabirds such as lesser black-backed gulls (LBBG) commonly feed mainly on higher-trophic-level organisms such as fish. However, intensive use of swimming crabs by LBBGs in the eastern North Sea has been noted over several years. Our investigation of this aspect of the food web by examining food remains from breeding LBBGs showed that swimming crabs accounted for more than half of the nutrition of LBBGs. Gulls selected larger individuals than expected, based on sizes of free-living swimming crabs. A long-term data set (2002-2006) shows that gulls took swimming crabs mainly in the early morning and late evening, suggesting that they might migrate vertically in the water column. Moreover, it shows that although swimming crabs occurred at considerable distances from the shore, LBBGs took this prey item exclusively from near the shore where it was most abundant. This suggests the existence of a possible energy threshold above which gulls experience a net energy loss, if they have to travel too far from their colony, where the abundance of swimming crabs is lower and the energy intake might thus not compensate for the long-distance flights. Swimming-crab abundance did not appear to be the primary factor influencing overall gull distribution. A simple bioenergetic model showed that the 22,000 individual LBBGs in the most important breeding colony in the south-eastern North Sea consumed approximately 35 million swimming crabs annually (i.e. 1590 swimming crabs per individual gull) during the breeding period. However, considering the high numbers of swimming crabs in the south-eastern North Sea (demonstrated by bottom-trawl surveys in 2005 and 2007) LBBGs are unlikely to exert top-down control on this prey. Conversely, a bottom-up effect is more likely, potentially enabling further increases in LBBG populations through increases in their most important prey item in the south-eastern North Sea.

  4. GEOGRAPHIC VARIATION IN BLOOD PLASMA PROTEIN CONCENTRATIONS IN YOUNG HERRING GULLS (LARUS ARGENTATUS) AND CASPIAN TERNS (STERNA CASPIA) FROM THE GREAT LAKES AND LAKE WINNIPEG. (R825216)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  5. Human Hair, Baltic Grey Seal (Halichoerus grypus) Fur and Herring Gull (Larus argentatus) Feathers as Accumulators of Bisphenol A and Alkylphenols.

    PubMed

    Nehring, Iga; Staniszewska, Marta; Falkowska, Lucyna

    2017-05-01

    The purpose of the study was to determine the concentration of bisphenol A (BPA), 4-tert-octylphenol (OP), and 4-nonylphenol (NP), in human hair, the fur of Baltic grey seals and the feathers of herring gulls. Hair was collected from 42 volunteers, while grey seal fur (n = 17) came from the seal centre in Hel (Marine Station of Institute of Oceanography, University of Gdansk) and gull covert feathers (n = 26) were collected from dead herring gulls along the Southern Baltic coast. Assays of phenol derivatives were conducted using the high performance liquid chromatography with fluorescence detection technique. In human hair, the mean BPA concentration amounted to 411.2 ng g(-1) dw, OP 131.2 ng g(-1) dw, NP 4478.4 ng g(-1) dw, in seal fur BPA 67.5 ng g(-1) dw, OP 62.8 ng g(-1) dw, NP 39.1 ng g(-1) dw, and in feathers BPA 145.1 ng g(-1) dw, OP 162.0 ng g(-1) dw, NP 37.7 ng g(-1) dw. The increase of the analysed EDCs in hair was significantly influenced by diet rich in products of marine origin, as well as hair colouring, heating up food in plastic containers, using home cleaning products without protective gloves and wearing newly purchased clothes without washing them first. The concentration of phenol derivatives in seal fur was influenced solely by the uniform diet rich in fish. In birds, the feeding area during molting significantly influenced the concentration of BPA, OP and NP found in covert feathers.

  6. Levels of DDT and PCB's in different stages of life cycle of the arctic tern Sterna paradisaea and the herring gull Larus argentatus

    SciTech Connect

    Lemmetyinen, R.; Rantamaki, P.; Karlin, A.

    1982-01-01

    ..sigma..DDT and PCB levels were analyzed in samples of arctic terns and herring gulls collected in the archipelago of southwestern Finland. Special attention was paid to the levels at various stages of the life cycle and in different sexes. The levels were nearly ten times higher in the herring gull. The highest loads were found in adult birds and in newly hatched chicks but the levels were much lower (only 7-12 % in the herring gull) in chicks just before fledgling. The levels in young gulls remained low until the end of August at least. Therefore it is plausible that the high levels found in adult gulls are a consequence of their wintering in the southern Baltic. The levels of ..sigma..DDT and PCB residues were significantly lower in female arctic terns than in male terns. Differences between the sexes were small in the herring gull. Thus it is possible that the female of the arctic tern is able to release pollutants, especially PCB residues, more effectively into eggs than the female of the herring gull. The biochemical mechanisms involved are not clear but a possible explanation may be different lipoprotein structures in the eggs of the species.

  7. Phosphorus in seagull colonies and the effect on the habitats. The case of yellow-legged gulls (Larus michahellis) in the Atlantic Islands National Park (Galicia-NW Spain).

    PubMed

    Otero, X L; Tejada, O; Martín-Pastor, M; De La Peña, S; Ferreira, T O; Pérez-Alberti, A

    2015-11-01

    During the period 1980-2000, the yellow-legged gull population underwent exponential growth due to an increase in the availability of anthropogenic food resources. The aim of this study was to highlight the effect of the gull colonies on the P soil cycle and the associated effects on coastal ecosystems. Samples of soil, water and faecal material were collected in a colony of yellow-legged gulls (Cíes Islands) and in a control area. Four sampling plots were installed in the study areas, and samples were collected in summer and winter in 1997 and 2011. Sample analysis included soil characterization and determination of the total P content (TP), bioavailable-P and fractionated-P forms in the soils and faecal material. The (31)P NMR technique was also used to determine organic P forms. Clear differences between the gull colony soils and the control soil were observed. The TP was 3 times higher in the gull colony soil, and the bioavailable P was 30 times higher than in the control soil. The P forms present at highest concentrations in the faecal material (P-apatite, P-residual and P-humic acid) were also present at high concentrations in the colony soil. The absence of any seasonal or annual differences in P concentration indicates that the P has remained stable in the soil over time, regardless of the changes in the gull population density. The degree of P saturation indicated that soils are saturated with P due to the low concentration of Fe/Al-hydroxides, which is consistent with a high P concentration in the run-off from the colonies. The P output from the colony soils to coastal waters may cause eutrophication of a nearby lagoon and the disappearance of a Zostera marina seagrass meadow. Similarly, the enrichment of P concentration in dune system of Muxieiro may induce irreversible changes in the plant communities. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Multiple introduction of Asian H5N1 avian influenza virus in Croatia by wild birds during 2005-2006 and isolation of the virus from apparently healthy black-headed gulls (Larus ridibundus).

    PubMed

    Savić, Vladimir; Labrović, Ankica; Zelenika, Tajana Amsel; Balenović, Mirta; Separović, Sanja; Jurinović, Luka

    2010-11-01

    This study describes the introduction and spread of avian influenza A (H5N1) subtype in Croatia. Seventeen isolates were identified during the period from October 2005 to March 2006, all originating from wild birds. The full-length nucleotide sequence analysis of the hemagglutinin (HA) gene of seven representative isolates revealed that three distinct genetic strains involved in the outbreaks, implicating at least three independent introductions of the virus into Croatia during a relatively short period of time. All three genetic strains belonged to clade 2.2 (Qinghai-like viruses) and each strain displayed significant similarity to concurrent H5N1 viruses from other European countries. The dominant strain of the virus was present in all four affected areas and in all three bird species (mute swan, mallard, and black-headed gull), indicating cross-species transmission of the virus. Two other genetic strains were found, together with the dominant strain, only in a marsh at the Adriatic coast during late February and early March 2006, which could be associated with frozen water surfaces in the continental part of Croatia as well as in Eastern Europe in early 2006 and the movement of birds toward warmer areas. This is also the first isolation of highly pathogenic avian influenza virus of H5N1 subtype from apparently healthy black-headed gulls.

  9. Pattern of mercury accumulation in different tissues of migratory and resident birds: Western reef heron (Egretta gularis) and Siberian gull (Larus heuglini) in Hara International Wetland-Persian Gulf.

    PubMed

    Majidi, Yousef; Bahramifar, Nader; Ghasempouri, Seyed Mahmoud

    2015-01-01

    The Hara Mangrove Forest of the Persian Gulf is undergoing increasing pollution from industrial, municipal, and petroleum sources; however, little research in ecotoxicology has been carried out in this ecosystem. In the present study, mercury distribution and accumulation were investigated in muscle, liver, kidney, and feather of the resident Western reef heron (n = 15) and the migratory Siberian gull (n = 15). We also evaluated the relation between Hg concentrations, sex, and age (juvenile vs. adult). Results showed that the highest concentrations of Hg were recorded in the feather (35 ± 0.14-3.0 ± 0.27 mg kg(-1) dw) and at 3.7-, 1.6-, and 1.3-fold in muscle, kidney, and liver, respectively. Concentrations of mercury in tissues of migratory birds were two times higher than in resident birds; geographical differences and feeding habits were used to explain these variations. We found a weak relationship between Hg concentrations in feathers and internal tissues (r ≤ 0.50); conversely, liver presented strong positive correlations with other soft tissues, especially kidney (p > 0.05; r = 0.82). Results showed that sex and age have no significant effects on T-Hg accumulation in these birds (p > 0.05; r < -0.01). Based on these findings, Hg concentrations were low in both species. Therefore, Hg contamination of this aquatic ecosystem is not a threat. Accordingly, we recommend the use of the Western reef heron as a bioindicator of mercury pollution in this region.

  10. Mercury concentrations in Common Tern Sterna hirundo and Slender-billed Gull Larus genei from the Shadegan Marshes of Iran, in north-western corner of the Persian Gulf.

    PubMed

    Zamani-Ahmadmahmoodi, Rasool; Alahverdi, Mostafa; Mirzaei, Roohallah

    2014-06-01

    We examined mercury levels in several tissues of Common Terns and Slender-billed Gulls collected from Shadegan Marshes of south-western Iran. In both species, total mercury content was highest in feathers followed by liver, kidney and muscle tissue. We found a significant correlation between mercury concentrations in kidney and breast feather (r=0.83, p<0.05), breast feather and liver (r=0.81, p<0.05) as well as liver and kidney (r=0.83, p<0.05). The contaminant levels in the feathers (11.53 and 15.32 μg/g in breast feather and tail feather, respectively) of Common Terns from Shadegan Marshes are higher than those reported for other tern species from elsewhere in the world, but feather mercury of Slender-billed Gull (6.61 and 5.35 μg/g in breast feather and tail feather, respectively) was similar to those reported for gull species worldwide. Mean values for mercury in the feather of two seabird species were higher than the levels known to cause adverse effects.

  11. [Geographic distribution of dengue fever cases in flooded zones from Villahermosa, Tabasco, in 2010].

    PubMed

    Jiménez-Sastré, Alejandro; Boldo-León, Xavier; Priego-Álvarez, Heberto; Quevedo-Tejero, Elsy; Zavala-González, Marco A

    2012-02-01

    To describe the geographical distribution of dengue fever cases in flooded areas of Villahermosa, Tabasco, in 2010. Cross-sectional, descriptive study. Universe: Colonies with antecedents of flooding during the inundation of the State, located in Villahermosa, Tabasco: Gaviotas Norte, Gaviotas Sur, La Manga 1th Section, La Manga 2nd Section and La Manga 3th Section. Convenience sample without randomization. location, dengue fever case. descriptive statistic. Software: SPSS version 11.0. 540 individuals were included. The distribution was: Gaviotas Norte, 36.1%; Gaviotas Sur, 24.8%; La Manga 1th Section, 13.8%; La Manga 2nd Section, 13.2%; and La Manga 3th Section, 12.1%. We found three cases with positive serology of IgG (0.6%) and five cases of positive IgM (0.9%). The geographical distribution was associated with the proximity to two water bodies: Rio Grijalva and Laguna El Encanto. It is necessary to reinforce preventive interventions in the proximity of bodies of fresh water.

  12. 20 CFR Appendix A to Subpart F of... - U.S. Seaports

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., GA St. Mary, GA Cocoa, FL Fernandina Beach, FL Fort Lauderdale, FL Fort Pierce, FL Jacksonville, FL Miami, FL Palm Beach, FL Port Canaveral, FL Port Everglades, FL Riviera, FL Aguadilla, PR Ceiba, PR... Carpinteria, CA Crockett, CA El Segundo, CA Eureka, CA Estero Bay, CA Gaviota, CA Huntington Beach, CA Long...

  13. Techniques for Minimizing and Monitoring the Impact of Pipeline Construction on Coastal Streams

    Treesearch

    Thomas W. Mulroy; John R. Storrer; Vincent J. Semonsen; Michael L. Dungan

    1989-01-01

    This paper describes specific measures recently employed for protection of riparian resources during construction of an oil and gas pipeline that crossed coastal reaches of 23 perennial and intermittent streams between Point Conception and Gaviota in Santa Barbara County, California. Flumes were constructed to maintain stream flow; anchored straw bales and silt fences...

  14. 3D Structural and Stratigraphic Architecture of the Northwest Santa Barbara Channel and Implications for Submarine Landslide Generation

    NASA Astrophysics Data System (ADS)

    Wright, A.; Kluesner, J. W.; Brothers, D. S.; Johnson, S. Y.

    2015-12-01

    Multiple submarine landslides have been previously documented on the north flank of the Santa Barbara Channel, and such failures are considered capable of generating local tsunamis. 2D seismic-reflection datasets provide a general view of regional framework geology, including faulting and folding associated with north-south compression. However, better understanding of the relationships between faults, folds, stratigraphic architecture, and submarine landslides can be obtained with 3D seismic datasets. In this study we use an industry 3D seismic-reflection volume that encompasses the slope and shelfbreak surrounding the Gaviota submarine landslide (3.8 km2) to investigate structural and stratigraphic controls on slope failure in this region. The depth-migrated seismic volume shows a network of stacked thrust faults, backthrusts, and splays that results in both broad and local zones of compression and folding along the slope and shelf. One localized zone of enhanced folding associated with small-offset thrust faults is located directly beneath the Gaviota landslide headwall, while another zone is located directly below an imaged seafloor fissure. In addition, 3D seismic attribute analysis provides insight into the shallow sedimentary section of the failed and non-failed sedimentary packages. Calculation of RMS amplitude and dominant frequency within a windowed region below the seafloor horizon delineates an apparent zone of gas-charged strata that onlaps onto older folded sediments. The up-dip limit of these gas-charged sediments aligns with the location of a seafloor fissure that extends westward from the Gaviota landslide headwall. We propose that the combination of deformation and fluid charging acted to pre-condition and trigger the failure of the Gaviota landslide, and as a result, the presence of these conditions along the fissure adjacent to the Gaviota landslide suggests this area should be considered landslide prone.

  15. 3D Structural and Stratigraphic Architecture of the Northwest Santa Barbara Basin: Implications for Slope Stability and Submarine Landslide Occurrence

    NASA Astrophysics Data System (ADS)

    Wright, A.; Brothers, D. S.; Kluesner, J.; Johnson, S. Y.

    2016-12-01

    Multiple submarine landslides have been documented on the north flank of the Santa Barbara Basin and such failures are considered capable of generating local tsunami hazards to the Santa Barbara region. Past 2D seismic reflection data has provided a general view of the regional framework geology resulting from north-south compression, but fails to identify along-strike variations of faults and folds. This study uses industry 3D seismic reflection data encompassing the slope surrounding the 3.8 km2-Gaviota submarine landslide to investigate structural and stratigraphic controls of slope failure in this region. The 3D depth-migrated volume shows a complex network of faults that result in both broad and local zones of compression, folding, and uplift along the slope. One localized zone of enhanced anticlinal folding and uplift associated with small-scale thrust faults is located directly beneath the Gaviota slide, while another is beneath a seafloor fissure west of the slide inferred to represent incipient failure. New high-resolution 2D transects constrain the character of shallow deformation above the locally uplifted blocks. 3D isopach maps indicate the seafloor fissures trend along a key threshold of thickness between the seafloor and a shallow horizon; the fissures are also coincide with an apparent zone of shallow, gas-charged strata that onlap the steeply dipping flanks of local anticlinal deformation. Because the seafloor gradient near the Gaviota slide is significantly lower than the internal friction angle for fine-grained marine sediments, we propose that a combination of active deformation, sediment compaction, and gas charging acted to precondition the slope of the Gaviota landslide for failure by reducing the shear strength. Similar factors occur beneath intact sections of the slope adjacent to the slide, which should be considered prone to future landsliding.

  16. Offshore environmental concerns mitigated by onshore-based, extended-reach drilling

    SciTech Connect

    1998-05-04

    Extended-reach drilling may alleviate California environmental concerns by targeting distant offshore plays using onshore localities adjacent to preexisting facilities. If successful, it may set a precedent for offshore development without the use of new offshore platforms, thereby reducing the risk of offshore spills. Politicians, environmentalists, and the industry will closely watch the Gaviota No. 7 well, an extended-reach well operated by Benton Oil and Gas Co. in partnership with Molino Energy Co. The companies aim to find sweet gas in the Gaviota structure, an anticline hemmed in by two faults, located abut 1 1/4 miles offshore in the Santa Barbara Channel. Frank Reiber, project manager for Benton, characterizes the technologies used in the Gaviota No. 7, as fairly routine. However, state officials hail this onshore-to-offshore technique as the only practical way to develop oil or gas in state waters, given the political and environmental constraints that have virtually closed all waters within the 3-mile limit for decades. The paper describes the drilling and production program.

  17. 76 FR 25149 - Endangered and Threatened Wildlife and Plants; Annual Notice of Findings on Resubmitted Petitions...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    .... luteirostris. C 8 Tangara peruviana.. Thraupidae......... black-backed Brazil. tanager. C 6 Strepera graculina... predators include the red-billed gull (Larus scopulinus), and southern black-backed gull (L....

  18. A survey for avian influenza from gulls on the coasts of the District of Pinamar and the Lagoon Salada Grande, General Madariaga, Argentina.

    PubMed

    Buscaglia, Celina

    2012-12-01

    In the present study, fecal samples obtained from kelp gulls (Larus dominicanus), brown-hooded gulls (Larus maculipennis), and Olrog's gulls (Larus atlanticus) on the coast of the District of Pinamar, and grey-hooded gulls (Larus cirrocephalus) on the coast of the Lagoon Salada Grande and surrounding wetlands, General Madariaga, Buenos Aires Province, Argentina, were tested for evidence of avian influenza virus over a period of 3 yr. This surveillance in free-living wild birds in the Buenos Aires Province started in October 2008. Additional samples, which included cloacal swabs, tracheal swabs, or pooled organs, were obtained from sick or dead gulls that arrived at the Fundaci6n Ecol6gica Pinamar or were provided by the Direcci6n de Seguridad en Playas, Municipalidad de Pinamar. Samples were pooled according to date, species, and area. Pooled samples were inoculated in 9- to 11-day-old eggs, and after 5 days, allantoic fluids were tested for evidence of hemagglutination. None of the samples was positive for avian influenza viruses.

  19. Environmental Impact Research Program. Techniques to Increase Efficiency and Reduce Effort in Applications of the Habitat Evaluation Procedures (HEP)

    DTIC Science & Technology

    1988-09-01

    Felis rufus Brewer’s sparrow Spizella breweri Brook trout Salvelinus fontinalis Brown shrimp Penaeus aztecus Brown thrasher Toxostoma rufum Brown trout...Brevoortia patronus Hairy woodpecker Picoides villosus Hard clam Mercenaria mercenaria Inland silverside Menidia beryllina Lake trout Salvelinus ... namaycush Largemouth bass Micropterus salmoides Lark bunting Calamospiza melanocorys Laughing gull Larus atricilla Least tern Sterna antillarum Lesser scaup

  20. Foraging success, kleptoparasitism and feeding techniques in scavenging seabirds: does crime pay?

    NASA Astrophysics Data System (ADS)

    Garthe, Stefan; Hüppop, Ommo

    1998-06-01

    Scavenging seabirds in the North Sea exploit discards with different success and by different feeding techniques. Northern gannet ( Sula bassana) had the highest foraging success index, followed by lesser black-backed gull ( Larus fuscus) and black-legged kittiwake ( Rissa tridactyla). Northern fulmar ( Fulmarus glacialis), mew gull ( Larus canus) and black-headed gull ( Larus ridibundus) were the least successful species. Ranking species according to the ratio of fish stolen from vs. lost to other species (=robbery index), northern gannet, great black-backed gull ( Larus marinus) and great skua ( Catharacta skua) were at the top, northern fulmar and black-legged kittiwake at the bottom. Varying compositions of the feeding flocks influenced the foraging success of the species significantly. Both body length and body mass of the birds can well explain species order in the robbery index but not in the foraging success index. Our hypothesis that the most successful species employ particular feeding techniques and/or exhibit the strongest kleptoparasitic abilities could be confirmed to a large extent but not totally. During reduced overall feeding rates, some less successful species and/or species with weaker kleptoparasitic capabilities fared better than during intense feeding rates as predicted, some others did not.

  1. Avian Cholera Causes Marine Bird Mortality in the Bering Sea of Alaska.

    PubMed

    Bodenstein, Barbara; Beckmen, Kimberlee; Sheffield, Gay; Kuletz, Kathy; Van Hemert, Caroline; Berlowski, Brenda; Shearn-Bochsler, Valerie

    2015-10-01

    The first known avian cholera outbreak among wild birds in Alaska occurred during November 2013. Liver, intestinal, and splenic necrosis consistent with avian cholera was noted, and Pasteurella multocida serotype 1 was isolated from liver and lung or spleen in Crested Auklets (Aethia cristatella), Thick-billed Murres (Uria lomvia), Common Eider (Somateria mollissima), Northern Fulmars (Fulmarus glacialis), and gulls (Larus spp.).

  2. Indian Surface Combatants: Sea Power for the 1990’s

    DTIC Science & Technology

    1991-09-01

    30 3. Soviet Petya II Class...32 Figure 7. Petya II Class Frigate.34 Figure 8. Whitby Class Frigate...........................35 Figure 9. Leopard Class...immediately with the acquisition of Petya II class frigates and assorted missile boats that provided a significant increase in capability (Larus, 1981

  3. Seabird-oil spill behavior study. Volume 2. Technical report. Final report

    SciTech Connect

    Varoujean, D.H.; Baltz, D.M.; Allen, B.; Power, D.; Schroeder, D.A.

    1983-04-01

    This volume provides a technical discussion of a two year (1980-1982) study on the behavior of seabirds encountering oil-contaminated water. An information survey, undertaken in this study, indicated that out of nearly 300 references to seabird/oil research only 12 articles addressed the topic of seabird behavior in the presence of oil. Available evidence does, however, indicate that seabirds avoid or try to avoid making contract with petroleum oil. Field observations and experiments conducted in the study areas of natural oil seeps in the Santa Barbara Channel, California, revealed that (1) abundance of seabirds in the study area was relatively low when compared to that in oil-free areas of the Channel; (2) the age and/or the residency status of Brown Pelicans (Pelecanus occidentalis), Western Gulls (Larus occidentalis) and Heerman's Gulls (Larus heermanni) were related to the frequency of interaction of these birds with oil.

  4. Seabird-oil spill behavior study. Volume 1. Executive summary. Final report

    SciTech Connect

    Varoujean, D.H.; Baltz, D.M.; Allen, B.; Power, D.; Schroeder, D.A.

    1983-04-01

    This volume contains a summary of findings of a two year (1980-1982) study on the behavior of seabirds encountering oil-contaminated water. An information survey, undertaken in the study, indicated that out of nearly 300 references to seabird/oil research only 12 articles addressed the topic of seabird behavior in the presence of oil. Available evidence does, however, indicate that seabirds avoid or try to avoid making contact with petroleum oil. Field observations and experiments conducted in the study areas of natural oil seeps in the Santa Barbara Channel California, revealed that: (1) abundance of seabirds in the study area was relatively low when compared to that in oil-free areas of the Channel; (2) the age and/or the residency status of Brown Pelicans (Pelecanus occidentalis), Western Gulls (Larus occidentalis) and Heermann's Gulls (Larus heermanni) were related to the frequency of interaction of these birds with oil.

  5. Metal levels in feathers of cormorants, flamingos and gulls from the coast of Namibia in southern Africa.

    PubMed

    Burger, J; Gochfeld, M

    2001-06-01

    Arsenic, cadmium, chromium, lead, manganese, mercury, selemium, and tin concentrations were measured in the feathers of Cape cormorant (Phalacrocorax capensis), Hartlaub's gull (Larus hartlaubii), kelp gull (Larus dominicanus), and lesser flamingo (Phoeniconaias minor) from the coast of Namibia in southern Africa. Metal concentrations in feathers represent the concentrations in the blood supply at the time of feather formation. Cape Cormorants are piscivores; kelp gulls are primarily piscivores; Hartlaub's gull is an omnivore; and lesser flamingos eat primarily blue-green algae and invertebrates filtered from the water and sediment of hypersaline lagoons. We predicted that metal concentrations would reflect these trophic level differences. There were significant species differences in the concentrations of all metals, with flamingos having the lowest levels, and cormorants having the highest levels of 4 metals but not mercury. The gulls had the highest levels of mercury, perhaps reflecting their more scavenging behavior.

  6. Chewing lice (Phthiraptera: Amblycera, Ischnocera) from Red Sea gulls with new host-parasite records.

    PubMed

    Al-Ahmed, Azzam; Shobrak, Mohammed; Nasser, Mohamed G E-D

    2014-04-23

    Knowledge about chewing lice from marine birds of the Red Sea is minimal. Five species of gulls were examined for chewing lice in three different localities of the Saudi Arabian Red Sea coast. Two gull species were examined for lice for the first time (Larus armenicus Buturlin, 1934 and Larus michahellis Naumann, 1840) and their lice represent new host-louse associations. Four species and two subspecies of lice were identified from 159 specimens collected. Actornithophilus piceus lari (Packard, 1870) and Austromenopon transversum (Denny, 1842) (suborder: Amblycera), and Quadraceps punctatus (Burmeister, 1838) and Saemundssonia lari (O. Fabricius, 1780) (suborder: Ischnocera) were recorded for the first time from Saudi Arabia and Red Sea birds. Taxonomic and ecological notes, type hosts, data on specimens examined, collecting localities, an identification key, and photographs of each species and subspecies are given. 

  7. Species differences in total mercury concentration in gulls from the Gulf of Gdansk (Southern Baltic).

    PubMed

    Szumiło-Pilarska, Emilia; Grajewska, Agnieszka; Falkowska, Lucyna; Hajdrych, Julia; Meissner, Włodzimierz; Frączek, Tomasz; Bełdowska, Magdalena; Bzoma, Szymon

    2016-01-01

    Aquatic birds occupy a high position in the trophic pyramid of the Baltic Sea. This means that they accumulate the greatest amount of harmful substances, including mercury, in their bodies. This element penetrates into their systems mainly via the alimentary canal. The amount of mercury absorbed from food depends on how badly the environment is polluted with this metal. The aim of this study was to discover the concentrations of total mercury (HgT) in the contour feathers, muscles, brain, lungs, liver, kidneys, heart and blood of four gull species Herring Gull (Larus argentatus), Common Gull (Larus canus), Black-headed Gull (Larus ridibundus) and Great Black-backed Gull (Larus marinus) and organic mercury (Hgorg) in the liver and brain of Herring Gull. The most important characteristic of the results obtained for the studied gulls was the statistically significant differences between the four species, probably resulting from their different diets-confirmed by stable-isotopes analysis (δ(15)N and δ(13)C). A logarithmic dependence was found between HgT in the blood and HgT in the brain of the Herring Gull. The authors suggest that among gulls burdened with the greatest mercury load, it is possible that the brain is protected by higher Hg accumulation in the muscles. The percentage share of Hgorg in the brain and liver of the Herring Gull depended on the concentration of HgT in these tissues and was always higher in the brain. In none of the cases, did the mercury levels assayed in the internal gulls' tissues exceed values associated with adverse health effects.

  8. Essaouira and Kala iris: two new orbiviruses of the Kemerovo serogroup, Chenuda complex, isolated from Ornithodoros (Alectorobius) maritimus ticks in Morocco.

    PubMed

    Chastel, C; Main, A J; Bailly-Choumara, H; Le Goff, F; Le Lay, G

    1993-12-01

    Essaouira and Kala Iris viruses were isolated from Ornithodoros (Alectorobius) maritimus ticks parasitizing yellow-legged gulls (Larus cachinnans) on the coast of Morocco in 1979 and 1981, respectively. Serological evidence indicates that these two viruses are new members of the Chenuda complex within the Kemerovo serogroup of the genus Orbivirus. Ecological, pathological, morphological, and physicochemical properties are compatible with these findings. The infectivity of these viruses for man and animals, including seabirds, remains unknown.

  9. Implementing Avian Inventory and Monitoring Efforts on Corps of Engineers Project Lands

    DTIC Science & Technology

    2007-06-01

    species (e.g., Eastern Screech Owl [Otus asio]) often respond well to calls and songs broadcast from a tape or CD player; therefore, incorporating a tape...Grasshopper Sparrow (Ammodramus savannarum), Lark Sparrow (Chondestes grammacus), and Eastern Meadowlark (Sternella magna)) (Askins 1993, Herkert 1994...species include many gull (Larus spp.) and tern (Sterna spp.) species, and many owl (e.g., Great-horned Owl [Bubo virgini- anus]) or nightjars

  10. Observations of a live Glaucous-winged Gull chick in an active Bald Eagle nest

    USGS Publications Warehouse

    Anthony, R.G.; Faris, J.T.

    2003-01-01

    We report an apparent nonlethal predation attempt on and subsequent adoption of a Glaucous-winged Gull (Larus glaucescens) chick by a pair of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Archipelago, Alaska. To the best of our knowledge, this is the first report of a live Glaucous-winged Gull chick in a Bald Eagle nest. We describe our observations of this occurrence and offer explanations on how it may have occurred.

  11. Seabird bycatch in Alaska demersal longline fishery trials: a demographic summary

    USGS Publications Warehouse

    Phillips, Elizabeth M.; Nevins, HannahRose M.; Hatch, Scott A.; Ramey, Andy M.; Miller, Melissa A.; Harvey, James T.

    2010-01-01

    The seasonal and spatial demographics are summarized for seabirds killed incidentally during gear modification trials for a demersal longline fishery in the Bering Sea. We examined 417 carcasses, including Northern Fulmar Fulmarus glacialis (n = 205), Glaucous-winged Gull Larus glaucescens (n = 103), Short-tailed Shearwater Puffinus tenuirostris (n = 48), Glaucous Gull Larus hyperboreus (n = 23), Slaty-backed Gull Larus schistisagus (n = 4), Black-legged Kittiwake Rissa tridactyla (n = 1), Laysan Albatross Diomedea immutabilis (n = 1), and unidentified gull species Larus spp. (n = 32). There was a significant male bias in the sex ratio of fulmars but not of gulls or shearwaters. For the top three species killed, the age composition of resident species was dominated numerically by adults (Northern Fulmar—86%; Glaucous-winged Gull—63%), whereas migrant species were primarily immature birds (Short-tailed Shearwater—71%). The majority of migratory Short-tailed Shearwaters (88%) were caught in July and August, whereas 70% of resident fulmars and gulls were caught in October and November. Age-class frequencies did not differ by month of capture, indicating that adult mortality is substantial. Eighty percent of the fulmars caught during July and August were within 200 km of two colonies in the Bering Sea, whereas only 7% of fulmars were caught in the same area during September to November. This is one of the first demographic summaries of seabird bycatch in Alaska longline fisheries. Additional studies of the species, age and sex of seabirds subject to fisheries-related mortality will provide data necessary to evaluate population-level impacts.

  12. Avian cholera causes marine bird mortality in the Bering Sea of Alaska

    USGS Publications Warehouse

    Bodenstein, Barbara L.; Kimberlee Beckmen,; Gay Sheffield,; Kathy Kuletz,; Van Hemert, Caroline R.; Berlowski-Zier, Brenda M.; Shearn-Bochsler, Valerie I.

    2015-01-01

    The first known avian cholera outbreak among wild birds in Alaska occurred during November 2013. Liver, intestinal, and splenic necrosis consistent with avian cholera was noted, and Pasteurella multocida serotype 1 was isolated from liver and lung or spleen in Crested Auklets (Aethia cristatella), Thick-billed Murres (Uria lomvia), Common Eider (Somateria mollissima), Northern Fulmars (Fulmarus glacialis), and Glaucous-winged Gulls (Larus glaucescens).

  13. An Evaluation of Techniques to Control Problem Bird Species on Landfill Sites

    NASA Astrophysics Data System (ADS)

    Cook, Aonghais; Rushton, Steven; Allan, John; Baxter, Andrew

    2008-06-01

    Birds feeding on landfill sites cause problems in terms of nuisance to neighbors, flight safety, a threat to public health, and affecting the day to day site operation. A number of control measures exist to deter problem species; however, research into their effectiveness across sites and for multiple species has been limited. We use a modeling approach in order to assess the effectiveness of nine techniques — pyrotechnics, hand-held distress calls, static distress calls, blank ammunition, a combination of blank and lethal use of ammunition, the use of falcons, the use of hawks, wailers and helium-filled bird-scaring kites — at deterring three commonly recorded species — the Black-headed Gull ( Larus ridibundus), the Herring Gull ( Larus argentatus) and the Lesser Black-backed Gull ( Larus fuscus) — from six landfill sites across the United Kingdom. The use of distress calls, falconry, and combinations of lethal and nonlethal use of ammunition were the most effective techniques for initially deterring birds from these sites. However, when habituation is considered, there is a clear difference between techniques such as falconry, which have a lethal aspect and may act to reinforce the deterrence, and the use of techniques such as distress calls, which do not. However there are problems related to legislation and public perception when lethal techniques are used.

  14. Increased prevalence of antibiotic-resistant E. coli in gulls sampled in Southcentral Alaska is associated with urban environments

    PubMed Central

    Atterby, Clara; Ramey, Andrew M.; Hall, Gabriel Gustafsson; Järhult, Josef; Börjesson, Stefan; Bonnedahl, Jonas

    2016-01-01

    Background Antibiotic-resistant bacteria pose challenges to healthcare delivery systems globally; however, limited information is available regarding the prevalence and spread of such bacteria in the environment. The aim of this study was to compare the prevalence of antibiotic-resistant bacteria in large-bodied gulls (Larus spp.) at urban and remote locations in Southcentral Alaska to gain inference into the association between antibiotic resistance in wildlife and anthropogenically influenced habitats. Methods Escherichia coli was cultured (n=115 isolates) from fecal samples of gulls (n=160) collected from a remote location, Middleton Island, and a more urban setting on the Kenai Peninsula. Results Screening of E. coli from fecal samples collected from glaucous-winged gulls (Larus glaucescens) at Middleton Island revealed 8% of isolates were resistant to one or more antibiotics and 2% of the isolates were resistant to three or more antibiotics. In contrast, 55% of E. coli isolates derived from fecal samples collected from large-bodied gulls (i.e. glaucous, herring [Larus argentatus], and potentially hybrid gulls) on the Kenai Peninsula were resistant to one or more antibiotics and 22% were resistant to three or more antibiotics. In addition, total of 16% of the gull samples from locations on the Kenai Peninsula harbored extended-spectrum cephalosporin-resistant E. coli isolates (extended-spectrum beta-lactamases [ESBL] and plasmid-encoded AmpC [pAmpC]), in contrast to Middleton Island where no ESBL- or pAmpC-producing isolates were detected. Conclusion Our findings indicate that increased prevalence of antibiotic resistance is associated with urban environments in Southcentral Alaska and presumably influenced by anthropogenic impacts. Further investigation is warranted to assess how migratory birds may maintain and spread antimicrobial-resistant bacteria of relevance to human and animal health. PMID:27649798

  15. Distribution of Ground-Nesting Marine Birds Along Shorelines in Glacier Bay, Southeastern Alaska: An Assessment Related to Potential Disturbance by Back-Country Users

    USGS Publications Warehouse

    Arimitsu, M.L.; Piatt, J.F.; Romano, Marc D.

    2007-01-01

    With the exception of a few large colonies, the distribution of ground-nesting marine birds in Glacier Bay National Park in southeastern Alaska is largely unknown. As visitor use increases in back-country areas of the park, there is growing concern over the potential impact of human activities on breeding birds. During the 2003i??05 breeding seasons, the shoreline of Glacier Bay was surveyed to locate ground-nesting marine birds and their nesting areas, including wildlife closures and historical sites for egg collection by Alaska Native peoples. The nesting distribution of four common ground-nesting marine bird species was determined: Arctic Tern (Sterna paradisaea), Black Oystercatcher (Haematopus bachmani), Mew Gull (Larus canus), and Glaucous-winged Gull (Larus glaucescens). Observations of less abundant species also were recorded, including Herring Gull (Larus argentatus), Red-throated Loon (Gavia stellata), Canada Goose (Branta canadensis), Willow Ptarmigan (Lagopus lagopus), Semipalmated Plover (Charadrius semipalmatus), Spotted Sandpiper (Actitis macularia), Least Sandpiper (Calidris minutilla), Parasitic Jaeger (Stercorarius parasiticus), and Aleutian Tern (Sterna aleutica). Nesting distribution for Arctic Terns was largely restricted to the upper arms of the bay and a few treeless islets in the lower bay, whereas Black Oystercatchers were more widely distributed along shorelines in the park. Mew Gulls nested throughout the upper bay in Geikie Inlet and in Fingers and Berg Bays, and most Glaucous-winged Gull nests were found at wildlife closures in the central and lower bays. Several areas were identified where human disturbance could affect breeding birds. This study comprises the first bay-wide survey for the breeding distribution of ground-nesting marine birds in Glacier Bay National Park, providing a minimum estimate of their numbers and distribution within the park. This information can be used to assess future human disturbance and track natural

  16. Increased prevalence of antibiotic-resistant E. coli in gulls sampled in southcentral Alaska is associated with urban environments

    USGS Publications Warehouse

    Atterby, Clara; Ramey, Andrew M.; Gustafsson Hall, Gabriel; Jarhult, Josef; Borjesson, Stefan; Bonnedahl, Jonas

    2016-01-01

    BackgroundAntibiotic-resistant bacteria pose challenges to healthcare delivery systems globally; however, limited information is available regarding the prevalence and spread of such bacteria in the environment. The aim of this study was to compare the prevalence of antibiotic-resistant bacteria in large-bodied gulls (Larus spp.) at urban and remote locations in Southcentral Alaska to gain inference into the association between antibiotic resistance in wildlife and anthropogenically influenced habitats.MethodsEscherichia coli was cultured (n=115 isolates) from fecal samples of gulls (n=160) collected from a remote location, Middleton Island, and a more urban setting on the Kenai Peninsula.ResultsScreening of E. coli from fecal samples collected from glaucous-winged gulls (Larus glaucescens) at Middleton Island revealed 8% of isolates were resistant to one or more antibiotics and 2% of the isolates were resistant to three or more antibiotics. In contrast, 55% of E. coli isolates derived from fecal samples collected from large-bodied gulls (i.e. glaucous, herring [Larus argentatus], and potentially hybrid gulls) on the Kenai Peninsula were resistant to one or more antibiotics and 22% were resistant to three or more antibiotics. In addition, total of 16% of the gull samples from locations on the Kenai Peninsula harbored extended-spectrum cephalosporin-resistant E. coli isolates (extended-spectrum beta-lactamases [ESBL] and plasmid-encoded AmpC [pAmpC]), in contrast to Middleton Island where no ESBL- or pAmpC-producing isolates were detected.ConclusionOur findings indicate that increased prevalence of antibiotic resistance is associated with urban environments in Southcentral Alaska and presumably influenced by anthropogenic impacts. Further investigation is warranted to assess how migratory birds may maintain and spread antimicrobial-resistant bacteria of relevance to human and animal health.

  17. Prolonged incubation behavior by a marbled godwit

    USGS Publications Warehouse

    Higgins, K.F.

    1974-01-01

    On 9 May 1972 I flushed a Marbled Godwit (Limosa fedoa) from a nest containing four eggs in a large field of mulched wheat stubble in northwestern Stutsman County, North Dakota. I revisited the nest on 31 May and on 7, 9, 12, 15, 16, 20, and 21 June, and found an incubating adult on the nest during all visits except 21 June. Another adult was seen near the nest site only on 9 May. On 12 June the eggs looked rotten, and the incubating bird seemed to have a crippled leg. On 21 June Ring-billed Gulls (Larus delawarensis) destroyed the eggs.

  18. Waterbird mortality from botulism type E in Lake Michigan (USA, Canada): an update

    USGS Publications Warehouse

    Brand, Christopher J.; Duncan, Ruth M.; Garrow, S.P.; Olson, D.; Schumann, L.E.

    1983-01-01

    Three outbreaks of botulism type E occurring in waterbirds on Lake Michigan since autumn 1976 are discussed. Natural ingestion of food containing type E toxin by Ring-billed Gulls (Larus delawarensis) and the presence of type E toxin in the blood from moribund gulls were demonstrated. Concurrent presence of type C and type E botulinal toxins was found in a die-off of Common Loons (Gavia immer). In combination with previous reported outbreaks, these incidents suggest that this disease is geographically widespread in Lake Michigan, and that environmental conditions conducive to type E botulinal toxin production and consumption occur in both summer and autumn.

  19. [The systematic position of mites of the genus Larinyssus Strandtmann (Gamasoidea, Rhinonyssidae), parasitizing gulls].

    PubMed

    Butenko, O M

    1975-01-01

    A study was carried out of the variability of mited colledted from 6 species of birds as follows: Larus argentatus Pontopp., L. minutus Pall., Gelochelidon nilotica Gm., Chlidonias leucoptera (Temm.), Ch. nigra (L.) and Sterna hirundo L. Structural peculiarities characteristic of the parasites of the above species have been revealed. The mites from St. hirundo were isolated into a distinct species, Larinyssus substerna sp. n., which is most close to L. sterna Fain, 1972. The new species differs from L. sterna in a smaller size of gnathosoma and chelicerae, lesser number of hypostomal setae and the presence of pigidial shields.

  20. [Characteristics of the plasmid profile of inositol- and rhamnose- negative strains of Salmonella typhimurium].

    PubMed

    Cízek, A; Mikula, I; Kovaríková, V

    1995-01-01

    S. typhimurium isolates obtained during a large outbreak of human salmonellosis associated with smoked mackerels in the Czech Republic as well as strains of S. typhimurium isolated from black headed gull (Larus ridibundus) were examined following biotyping, phage typing, plasmid profiling and restriction endonuclease analysis (Eco RI, Hind III and Bam HI) of plasmid DNA. The epidemic strain of S. typhimurium and two isolates from environment of nesting colony black-headed gull were meso-inositol and L-rhamnose negative, phage type 141. The isolates from human and environment of nesting colony were found to share the same plasmid profile and REA.

  1. Bird blood as bioindicator for mercury in the environment.

    PubMed

    Kahle, S; Becker, P H

    1999-12-01

    Mercury concentrations were studied in blood, down and feathers of Common Gull (Larus canus L.) to investigate the suitability of bird blood as a matrix for biomonitoring of mercury in the marine environment. Chicks were collected in 1996 on the Elbe river and the Jade Bay. Like the side feathers, blood indicated site differences in mercury contamination. Correlational analyses showed that mercury concentrations in blood are significantly related to levels in side feathers (p < 0.001; Pearson), but not to those in down (p > 0.05; Pearson). Therefore, blood can be considered as a suitable matrix to indicate the current mercury burden in wild birds.

  2. Salmonella in California wildlife species: prevalence in rehabilitation centers and characterization of isolates.

    PubMed

    Smith, Woutrina A; Mazet, Jonna A K; Hirsh, Dwight C

    2002-09-01

    Fecal samples from 212 selected marine mammals, marine birds, and raptors were cultured for Salmonella spp. on arrival at rehabilitation centers in California from May 1999 through July 2000. Salmonella spp. were cultured from nine (4%) animals, and seven serotypes were isolated: Johannesberg, Montevideo, Newport, Ohio, Saint Paul, Enteritidis Group D, and 4,5,12:1 Monophasic. One western gull (Larus occidentalis) had two serotypes. Antibiotic susceptibilities and chromosomal fingerprints were evaluated for Salmonella isolates. Some isolates were resistant to gentamicin, amoxicillin-clavulanic acid, and ampicillin. Chromosomal fingerprints with XbaI and XhoI restriction enzymes differed between serotypes but not between individuals carrying the same serotype of Salmonella.

  3. Ornithodoros (Alectorobius) capensis Neumann (Acari: Ixodoidea: Argasidae), a parasite of seabirds, established along the southeastern seacoast of the United States.

    PubMed

    Keirans, J E; Hutcheson, H J; Oliver, J H

    1992-03-01

    Ornithodoros (Alectorobius) capensis Neumann, an ectoparasite of seabirds found circumglobally in the tropics and subtropics, has become established along the southeastern seacoast of the United States. The tick has been found feeding primarily on brown pelicans, Pelecanus occidentalis, but also has been found on the laughing gull, Larus atricilla, and the American oystercatcher, Haematopus palliatus. We report here the presence of O. (A.) capensis from New Hanover and Brunswick counties (near the mouth of the Cape Fear River) in North Carolina, to the Charleston Harbor area of South Carolina and thence south to Cumberland Island (a barrier island) in Camden County, Georgia, just north of the Florida state line.

  4. Herring gull eggs indicate stabilizing Great Lakes PCB concentrations

    SciTech Connect

    Stow, C.

    1995-12-31

    The author evaluated the fit of 3 alternative models to herring gull (Larus argentatus) egg PCB concentration data from 1978--1992 to examine whether PCB levels were decreasing or had ceased to decline. The best fit models indicate that, following initial declines, no discernible PCB decreases are occurring in 4 of the 5 lakes. Only Lake Erie indicates a continued PCB decline, though the Erie data may be too noisy to differentiate model fits. These results are consistent with previous analyses indicating stable PCB concentrations in Lake Michigan fishes and suggest that further improvements may be too slow to be of practical importance from a management perspective.

  5. Retraction of a longevity record for a 36-year-old herring gull

    USGS Publications Warehouse

    Jonkel, G.M.; Pettingill, O.S.

    1974-01-01

    Full text: The longevity record for a 36-year-old Herring Gull, Larus argentatus (Pettingill 1967, Auk 84: 123), is erroneous. Herring Gull with band number A-676871, the basis of the record, was found dead on 20 June 1966 on the shore of Little Traverse Bay near Petoskey, Michigan, and reported to the Bird Banding Laboratory. The laboratory then mistakenly advised Pettingill that this gull was banded by him on 29 June 1930 on coastal Maine. He actually banded Herring Gull number A-676871 as a young bird on one of the Beaver Islands in Lake Michigan on 8 July 1948. The gull was thus 18 instead of 36 years old.

  6. Populations and productivity of seabirds at South Marble Island, Glacier Bay, Alaska, during May-July, 1999

    USGS Publications Warehouse

    Zador, Stephani G.; Piatt, John F.

    1999-01-01

    In the course of directed research on glaucous-winged gulls, we investigated the numbers and activities of all breeding and non-breeding seabirds associated with South Marble Island in Glacier Bay, Alaska, during mid-May to late July, 1999. Most observations were made from the island; additional observations were made during transportation to and from the island. Data were collected on the presence and numbers of all seabirds observed. Detailed information on breeding chronology and productivity were also collected for glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), black-legged kittiwakes (Rissa tridactyla), and black oystercatchers (Haemantopus bachmani).

  7. Habitat Suitability Index Models: Laughing gull

    USGS Publications Warehouse

    Zale, Alexander V.; Mulholland, Rosemarie

    1985-01-01

    A review and synthesis of existing information were used to develop a habitat model for laughing gull (Larus atricilla). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1.0 (optimally suitable habitat) for areas along the Gulf of Mexico coast. Habitat suitability indices are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for application of the model and techniques for measuring model variables are described.

  8. Morphological Variation on Isolated Populations of Praocis (Praocis) spinolai

    PubMed Central

    Benítez, Hugo A.; Pizarro-Araya, Jaime; Bravi, Raffaella; Sanzana, María-José; Alfaro, Fermín M.

    2014-01-01

    In this study, the morphological variations of four geographically isolated populations of Praocis (Praocis) spinolai Gay & Solier (Coleoptera: Tenebrionidae) in the transitional coastal desert, Chile, were studied. The study was conducted in the coastal area of Punta de Choros and Los Choros-Archipelago, which includes three islands: Choros, Damas, and Gaviota. 113 specimens of the species P. (P.) spinolai belonging to the four locations sampled were collected analyzed with geometric morphometrics techniques to explore the pattern of shape variation on the different isolated environments. The principal component analysis revealed a well-defined pattern of variation between the populations analyzed. Moreover, differences between populations emerged also from the canonical variation analysis and were confirmed by the Procrustes ANOVA. All analyses performed confirmed the existence of a pattern of variation, due to the isolation of the populations and to environmental effects. The islands are subject to more arid pressures than the continent, where there is a more stable environment and the presence of coastal wetlands and the coastal range of mountains act together and enable fog condensation. This study indicates the existence of a clear pattern of variation, which indicates an evolutionary trend among the population examined. PMID:25373158

  9. Submarine landslides of the Southern California Borderland

    USGS Publications Warehouse

    Lee, H.J.; Greene, H. Gary; Edwards, B.D.; Fisher, M.A.; Normark, W.R.

    2009-01-01

    Conventional bathymetry, sidescan-sonar and seismic-reflection data, and recent, multibeam surveys of large parts of the Southern California Borderland disclose the presence of numerous submarine landslides. Most of these features are fairly small, with lateral dimensions less than ??2 km. In areas where multibeam surveys are available, only two large landslide complexes were identified on the mainland slope- Goleta slide in Santa Barbara Channel and Palos Verdes debris avalanche on the San Pedro Escarpment south of Palos Verdes Peninsula. Both of these complexes indicate repeated recurrences of catastrophic slope failure. Recurrence intervals are not well constrained but appear to be in the range of 7500 years for the Goleta slide. The most recent major activity of the Palos Verdes debris avalanche occurred roughly 7500 years ago. A small failure deposit in Santa Barbara Channel, the Gaviota mudflow, was perhaps caused by an 1812 earthquake. Most landslides in this region are probably triggered by earthquakes, although the larger failures were likely conditioned by other factors, such as oversteepening, development of shelf-edge deltas, and high fluid pressures. If a subsequent future landslide were to occur in the area of these large landslide complexes, a tsunami would probably result. Runup distances of 10 m over a 30-km-long stretch of the Santa Barbara coastline are predicted for a recurrence of the Goleta slide, and a runup of 3 m over a comparable stretch of the Los Angeles coastline is modeled for the Palos Verdes debris avalanche. ?? 2009 The Geological Society of America.

  10. Detecting compaction disequilibrium with anisotropy of magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Schwehr, Kurt; Tauxe, Lisa; Driscoll, Neal; Lee, Homa

    2006-11-01

    In clay-rich sediment, microstructures and macrostructures influence how sediments deform when under stress. When lithology is fairly constant, anisotropy of magnetic susceptibility (AMS) can be a simple technique for measuring the relative consolidation state of sediment, which reflects the sediment burial history. AMS can reveal areas of high water content and apparent overconsolidation associated with unconformities where sediment overburden has been removed. Many other methods for testing consolidation and water content are destructive and invasive, whereas AMS provides a nondestructive means to focus on areas for additional geotechnical study. In zones where the magnetic minerals are undergoing diagenesis, AMS should not be used for detecting compaction state. By utilizing AMS in the Santa Barbara Basin, we were able to identify one clear unconformity and eight zones of high water content in three cores. With the addition of susceptibility, anhysteretic remanent magnetization, and isothermal remanent magnetization rock magnetic techniques, we excluded 3 out of 11 zones from being compaction disequilibria. The AMS signals for these three zones are the result of diagenesis, coring deformation, and burrows. In addition, using AMS eigenvectors, we are able to accurately show the direction of maximum compression for the accumulation zone of the Gaviota Slide.

  11. Cruise summary for P-1-02-SC: acoustic imaging of natural oil and gas seeps and measurement of dissolved methane concentration in coastal waters near Pt. Conception, California

    USGS Publications Warehouse

    Lorenson, T.D.; Dougherty, Jennifer A.; Ussler, William; Paull, Charles K.

    2003-01-01

    Water-column acoustic anomalies and methane concentrations were documented in coastal waters surrounding Pt. Conception, California, in March 2002. The purpose of this survey, supported by the Minerals Management Service, was to locate active oil and gas seeps in the area as a background for further studies to determine hydrocarbon flux, mainly oil, into the environment. Objectives in reaching this goal are to (1) document the locations and geochemically fingerprint natural seeps within the offshore southern Santa Maria Basin; (2) geochemically fingerprint coastal tar residues and potential sources, both onshore and offshore, in this region; (3) establish chemical correlations between offshore active seeps and coastal residues thus linking seep sources to oil residues; (4) measure the rate of natural seepage of individual seeps and attempt to assess regional natural oil and gas seepage rates; (5) attempt to predict transport pathways of oil from seep sources to the coastline and; (6) interpret the petroleum system history for the natural seeps. This survey, addressing objective 1, focused on the area from offshore Surf Beach to the north and Gaviota to the south in water depths ranging from 20 to 500m. In addition, nine stations were sampled outside this area to provide a regional context. Water-column methane concentrations were measured in water samples collected from the R/V Point Sur with Niskin bottles from various depths. A total of 724 water samples from 94 stations were collected.

  12. Stratigraphy of the fluvial deposits of the Salado river basin, Buenos Aires Province: Lithology, chronology and paleoclimate

    NASA Astrophysics Data System (ADS)

    Fucks, E.; Pisano, M. F.; Huarte, R. A.; Di Lello, C. V.; Mari, F.; Carbonari, J. E.

    2015-07-01

    The regional landscape of the Salado depression is related to weathering, eolian and fluvial processes generated under different climatic conditions. Although during most of the Holocene the climatic conditions were warm and humid, previously, a vast plain dominated by deflation processes and enhanced by weathering processes was developed in an arid environment. Fluvial deposits produced afterwards are continuous and lithologically homogeneous, which allows differentiation and characterization of the entire stratigraphic sequence. The stratigraphic units of this area, closely related to the paleoclimatic conditions, are recognized and characterized. Three lithostratigraphic units of fluvial origin (Members) and two paleosols have been differentiated. The first ones were grouped in the Luján Formation. Some of the units are related to other ones previously recognized in this area (La Chumbiada Member and La Pelada Geosol), but others have no similarity or relationship with previously known units (Gorch and Puente Las Gaviotas Members, and Frigorífico Belgrano Geosol). Radiocarbon ages suggest that the fluvial sequences were deposited after the glacial maximum, corresponding to MIS 1, except for the basal levels of the lower member which is late Late Pleistocene. Although the general paleoclimatic conditions were related to warm and humid climate, events related to water deficits were also recognized, which could be related to the Younger Dryas, the middle Holocene and the late Holocene.

  13. Morphological variation on isolated populations of Praocis (Praocis) spinolai.

    PubMed

    Benítez, Hugo A; Pizarro-Araya, Jaime; Bravi, Raffaella; Sanzana, María-José; Alfaro, Fermín M

    2014-01-26

    In this study, the morphological variations of four geographically isolated populations of Praocis (Praocis) spinolai Gay & Solier (Coleoptera: Tenebrionidae) in the transitional coastal desert, Chile, were studied. The study was conducted in the coastal area of Punta de Choros and Los Choros-Archipelago, which includes three islands: Choros, Damas, and Gaviota. 113 specimens of the species P. (P.) spinolai belonging to the four locations sampled were collected analyzed with geometric morphometrics techniques to explore the pattern of shape variation on the different isolated environments. The principal component analysis revealed a well-defined pattern of variation between the populations analyzed. Moreover, differences between populations emerged also from the canonical variation analysis and were confirmed by the Procrustes ANOVA. All analyses performed confirmed the existence of a pattern of variation, due to the isolation of the populations and to environmental effects. The islands are subject to more arid pressures than the continent, where there is a more stable environment and the presence of coastal wetlands and the coastal range of mountains act together and enable fog condensation. This study indicates the existence of a clear pattern of variation, which indicates an evolutionary trend among the population examined. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  14. The importance of survey timing in monitoring breeding seabird numbers

    USGS Publications Warehouse

    Johnson, C.M.; Krohn, W.B.

    2001-01-01

    We conducted weekly aerial surveys of islands along the central Maine coast from April-June of 1993-1997 and used aerial photographs to determine peak nest count dates for Double-crested Cormorants (Phalacrocorax auritus), Herring Gulls (Larus argentatus) and Great Black-Backed Gulls (Larus marinus). These data also were used to determine the potential effect of survey timing on the ability to detect long-term trends in the abundance of these species. The number of cormorant nests in the study area peaked in mid-June, while Great Black-backed and Herring gulls peaked in late May and early June, respectively. Peak nesting dates generally were consistent for each island across years, but varied by up to a month between islands during a given year. A 10-year monitoring program using annual surveys conducted between 23 May and 23 June, or biennial surveys conducted from 2-17 June, would have an 80% probability of detecting annual changes of ??5% for all three species in this region. Received 1 November 2000, accepted 4 December 2000.

  15. Flexibility of habitat use in novel environments: insights from a translocation experiment with lesser black-backed gulls

    PubMed Central

    Arriero, Elena; Huttunen, Markku J.; Juvaste, Risto; Müller, Inge; Thorup, Kasper; Wikelski, Martin

    2017-01-01

    Being faced with unknown environments is a concomitant challenge of species' range expansions. Strategies to cope with this challenge include the adaptation to local conditions and a flexibility in resource exploitation. The gulls of the Larus argentatus-fuscus-cachinnans group form a system in which ecological flexibility might have enabled them to expand their range considerably, and to colonize urban environments. However, on a population level both flexibility and local adaptation lead to signatures of differential habitat use in different environments, and these processes are not easily distinguished. Using the lesser black-backed gull (Larus fuscus) as a system, we put both flexibility and local adaptation to a test. We compare habitat use between two spatially separated populations, and use a translocation experiment during which individuals were released into novel environment. The experiment revealed that on a population-level flexibility best explains the differences in habitat use between the two populations. We think that our results suggest that the range expansion and huge success of this species complex could be a result of its broad ecological niche and flexibility in the exploitation of resources. However, this also advises caution when using species distribution models to extrapolate habitat use across space. PMID:28280543

  16. Newcastle disease in wild water birds in western Canada, 1990

    PubMed Central

    Wobeser, Gary; Leighton, Frederick A.; Norman, Robert; Myers, Davis J.; Onderka, Detlef; Pybus, Marjo J.; Neufeld, James L.; Fox, Glen A.; Alexander, Dennis J.

    1993-01-01

    This report describes the investigation of mortality of double-crested cormorants (Phalacrocorax auritus), white pelicans (Pelecanus erythrorhynchos), and gulls (Larus spp.) in Alberta, Saskatchewan, and Manitoba during late summer 1990. Techniques used varied among areas, but virological and histopathological examination of birds was done in each area. The major clinical sign in cormorants was inability to fly, often with unilateral wing or leg paralysis. Focal nonsuppurative inflammation was present in the brain and spinal cord of cormorants and pelicans. Newcastle disease virus (NDV) was isolated from cormorants, a pelican, and a ring-billed gull (Larus delawarensls) from Saskatchewan. Cormorants from Alberta were positive for NDV in an immunofluorescent test. Most of the viruses were classed as velogenic and all had a similar monoclonal antibody profile to viruses from the 1970 to 1974 panzootic. Approximately half of cormorant, pelican, and gull eggs collected from affected colonies in the spring of 1991 had antibody to NDV. Antibody was also present in cormorant eggs from the Great Lakes. No unusual mortality was detected at any colony in 1991. Fledgling cormorants and gulls from colonies where mortality occurred in 1990 did not have antibody to NDV in June-July 1991. The overall extent of mortality among water birds and the source of the virus were not determined. ImagesFigure 2. PMID:17424240

  17. Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast.

    PubMed

    Bustnes, Jan Ove; Helberg, Morten; Strann, Karl-Birger; Skaare, Janneche Utne

    2006-12-01

    Organochlorine (OC) residues were measured in eggs and blood of different subspecies of the lesser black-backed gull, Larus fuscus, on the Norwegian coast: a) increasing L. f. intermedius in the North Sea; b) endangered L. f. fuscus near the Arctic Circle; c) L. f. fuscus and greyish-mantled gulls, with a L. f. intermedius appearance, in the Barents Sea region. The dominating OCs in lesser black-backed gulls were polychlorinated biphenyls (PCB) and p,p'-dichlorodiphenyldichloroethylene (DDE). DDE and beta-hexachlorocyclohexane (beta-HCH) residues were higher in L. f. fuscus compared to L. f. intermedius and greyish-mantled birds in the Barents Sea region. In the latter area, blood residues of PCB and DDE in lesser black-backed gulls were as high as in great black-backed gulls, Larus marinus, while in the other regions they were lower. The higher DDE residues in endangered L. f. fuscus compared to increasing L. f. intermedius and greyish-mantled birds, which are invading northern Norway, suggest that OCs may have played a role in the population decline of L. f. fuscus, possibly in combination with nutrient stress.

  18. Haldane's rule revisited: do hybrid females have a shorter lifespan? Survival of hybrids in a recent contact zone between two large gull species.

    PubMed

    Neubauer, G; Nowicki, P; Zagalska-Neubauer, M

    2014-06-01

    Haldane's rule predicts that particularly high fitness reduction should affect the heterogametic sex of interspecific hybrids. Despite the fact that hybridization is widespread in birds, survival of hybrid individuals is rarely addressed in studies of avian hybrid zones, possibly because of methodological constraints. Here, having applied capture-mark-recapture models to an extensive, 19-year-long data set on individually marked birds, we estimate annual survival rates of hybrid individuals in the hybrid zone between herring (Larus argentatus) and Caspian (Larus cachinnans) gulls. In both parental species, males have a slightly higher survival rate than females (model-weighted mean ± SE: herring gull males 0.88 ± 0.01, females 0.87 ± 0.01, Caspian gull males 0.88 ± 0.01, females 0.87 ± 0.01). Hybrid males do not survive for a shorter time than nonhybrid ones (0.88 ± 0.01), whereas hybrid females have the lowest survival rate among all groups of individuals (0.83 ± 0.03). This translates to a shorter adult (reproductive) lifespan (on average by 1.7-1.8 years, i.e. ca 25%) compared with nonhybrid females. We conclude that, in line with Haldane's rule, the lower survival rate of female hybrids may contribute to selection against hybrids in this hybrid zone.

  19. Identification and characterization of a novel adenovirus in the cloacal bursa of gulls

    SciTech Connect

    Bodewes, R.; Bildt, M.W.G. van de; Schapendonk, C.M.E.; Leeuwen, M. van; Boheemen, S. van; Jong, A.A.W. de; Osterhaus, A.D.M.E.; Smits, S.L.; Kuiken, T.

    2013-05-25

    Several viruses of the family of Adenoviridae are associated with disease in birds. Here we report the detection of a novel adenovirus in the cloacal bursa of herring gulls (Larus argentatus) and lesser black-backed gulls (Larus fuscus) that were found dead in the Netherlands in 2001. Histopathological analysis of the cloacal bursa revealed cytomegaly and karyomegaly with basophilic intranuclear inclusions typical for adenovirus infection. The presence of an adenovirus was confirmed by electron microscopy. By random PCR in combination with deep sequencing, sequences were detected that had the best hit with known adenoviruses. Phylogenetic analysis of complete coding sequences of the hexon, penton and polymerase genes indicates that this novel virus, tentatively named Gull adenovirus, belongs to the genus Aviadenovirus. The present study demonstrates that birds of the Laridae family are infected by family-specific adenoviruses that differ from known adenoviruses in other bird species. - Highlights: ► Lesions typical for adenovirus infection detected in cloacal bursa of dead gulls. ► Confirmation of adenovirus infection by electron microscopy and deep sequencing. ► Sequence analysis indicates that it is a novel adenovirus in the genus Aviadenovirus. ► The novel (Gull) adenovirus was detected in multiple organs of two species of gulls.

  20. Tracing waterbird exposure to total mercury and selenium: a case study at the solar saltworks of Thyna (sfax, Tunisia).

    PubMed

    Ramírez, Francisco; Abdennadher, Aida; Sanpera, Carola; Jover, Lluís; Hobson, Keith A; Wassenaar, Leonard I

    2011-06-15

    Saltworks have emerged as important alternative/complementary feeding habitats for avifauna. However, the consequences of such habitat shifts in terms of changes in exposure to contaminants are poorly understood. We evaluated the exposure of the waterbird community breeding at the saltworks of Thyna (Tunisia) to total Hg (THg) and Se according to their differential use of saltworks dietary resources, as revealed by δ¹³C and δ¹⁵N values in their eggs (included species [n] -sorted according to increasing reliance on saltworks resources: Yellow-legged Gull Larus michahellis [12], Common Tern Sterna hirundo [12], Slender-billed Gull Larus genei [15], Little Egret Egretta garzetta [20], and Pied Avocet Recurvirostra avosetta [22]). Concentrations of THg and Se were under the threshold points for deleterious effects. Egg THg concentrations significantly decreased as the dietary contribution of saltworks resources increased (mean: 3.23, 1.66, 0.76, 0.4, and 0.27 μg/g dw, respectively). Conversely, egg Se concentrations did not vary according to foraging habitats (2.49, 2.96, 2.61, 3.27, and 1.5 μg/g dw, respectively). Tracing waterbird exposure to THg and Se at saltworks was feasible through the use stable isotopic assays of eggs. Birds using saltworks are not exposed to higher concentrations of THg and Se than in adjacent marine habitats.

  1. Persistent organic pollutant and mercury concentrations in eggs of ground-nesting marine birds in the Canadian high Arctic.

    PubMed

    Peck, Liam E; Gilchrist, H Grant; Mallory, Conor D; Braune, Birgit M; Mallory, Mark L

    2016-06-15

    We collected eggs of eight marine bird species from several colony sites in the Canadian high Arctic located at approximately 76°N and analyzed them for concentrations of legacy persistent organic pollutants (POPs) and mercury. We provide the first report on concentrations of POPs in eggs of three Arctic species (Thayer's gull Larus thayeri, Sabine's gull Xema sabini, Ross's Gull Rhodostethia rosea), and we found significant differences in each of the POP profiles among the five species with sufficient data for statistical comparisons (Thayer's gull, black guillemot Cepphus grylle, Sabine's gull, Arctic tern Sterna paradisaea and common eider Somateria mollissima borealis). The Ross's Gull had unexpectedly high POP concentrations relative to the other species examined, although this was based on a single egg, while glaucous gull Larus hyperboreus eggs from our sampling location had very low POPs. Sabine's gulls had the lowest Hg of the eggs studied, consistent with their low trophic position, but concentrations of their legacy POPs were higher than expected. We also noted that total hexachlorocyclohexanes were higher than reported elsewhere in the circumpolar Arctic in three species. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Gull eggs--food of high organic pollutant content?

    PubMed

    Pusch, Kerstin; Schlabach, Martin; Prinzinger, Roland; Wing Gabrielsen, Geir

    2005-06-01

    A wide range and occasionally high levels of persistent organic pollutants (POPs) are reported in Arctic regions, especially among top predators. Polar bears (Ursus maritimus), arctic foxes (Alopex lagopus) and some gull species (Larus spp.) often have high levels of these fat-soluble pollutants. Gulls deposit significant levels of these contaminants in their eggs. In northern regions, gull eggs are part of the traditional human diet. In the present study we have investigated the levels of POPs in gull eggs in order to determine the tolerable weekly intake (TWI) for humans. Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in 214 gull eggs collected in the spring of 2001-02. The eggs were collected from four gull species (herring gulls (Larus argentatus), great black-backed gulls (L. marinus), lesser black-backed gulls (L. fuscus) and glaucous gulls (L. hyperboreus)) at 12 different locations in Northern Norway, on the Faroe Islands and on Svalbard. The pollutant levels in gull eggs were found to be 65.5 +/- 26.9 pg toxic equivalent (TE) for dioxin and PCB g(-1) wet weight. Based on these findings and the TWI-value determined by the EU Scientific Committee on Food it is advised that children, young women and pregnant and nursing women should not eat gull eggs. Other people should limit their intake of eggs to an absolute minimum, considering the health risks associated with gull egg intake.

  3. Lead and cadmium in wild birds in southeastern Spain

    SciTech Connect

    Garcia-Fernandez, A.J.; Sanchez-Garcia, J.A.; Luna, A.; Jimenez-Montalban, P.

    1995-12-01

    The main purpose of this study was to monitor exposure to lead and cadmium in wild birds in Murcia, a southeastern region of Spain on the Mediterranean coast. This region lies on one of the African-European flyways. Samples of liver, kidney, brain, bone, and whole blood from several species of wild birds were obtained during 1993. The authors found a clear relationship between cadmium and lead concentrations in birds and their feedings habits. Vultures (Gyps fulvus) had the highest concentrations of lead (mean 40 {micro}g/dl in blood), and seagulls (Larus argentatus and Larus ridibundus) the highest concentrations of cadmium (mean 4.43 {micro}g/g in kidney). Insectivores had high concentrations of both metals, and diurnal and nocturnal raptors showed the lowest tissue concentrations. The findings that tissue and blood concentrations were generally not elevated suggests environmental (rather than acute) exposure. Birds from more industrialized areas of the region studied here had higher concentrations of both lead and cadmium.

  4. Seabird eggs as bioindicators of chemical contamination in Chile.

    PubMed

    Cifuentes, Jacqueline Muñoz; Becker, Peter H; Sommer, Ute; Pacheco, Patricia; Schlatter, Roberto

    2003-01-01

    Seabird eggs were used as bioindicators of chemical contamination in Chile. Brown-hooded Gull (Larus maculipennis), Kelp Gull (Larus dominicanus), Trudeau's Tern (Sterna trudeaui), Neotropic Cormorant (Phalacrocorax brasilianus), and Pink-footed Shearwater (Puffinus creatopus) eggs were sampled at different breeding sites during the 1990s. Mercury and organochlorines (PCBs, DDT, HCB, HCH, and PCP) were quantified to reveal the interspecific differences, spatial and temporal trends in contamination levels. Trudeau's Tern displayed the highest levels of mercury (486 ng g(-1) wet weight). The highest sumDDT concentrations were measured in Brown-hooded Gulls (726 ng g(-1)). PCB levels were similar among the species (102-236 ng g(-1)), but the composition of the PCB mixture was different in Pink-footed Shearwaters. With the exception of the Brown-hooded Gull, all species studied presented similar and low levels of organochlorines (sumOHa). Residues of PCB and related compounds were not detected in any of the seabird eggs analyzed in Chile. Geographical variation was low, although levels of industrial chemicals were slightly higher in eggs from Concepción Bay, and agricultural chemicals in eggs from Valdivia. Also interannual variation was low, but some evidence was found of decreasing levels in gull eggs throughout the time of the study. The causes of the low levels and small variability in space and time of environmental chemicals in Chilean seabirds are discussed. We propose the use of seabirds in future monitoring of the development of chemical contamination in Chile.

  5. Dioxins and dl-PCBs in gull eggs from Spanish Natural Parks (2010-2013).

    PubMed

    Morales, Laura; Gene'rosa Martrat, Ma; Parera, Jordi; Bertolero, Albert; Ábalos, Manuela; Santos, Francisco Javier; Lacorte, Silvia; Abad, Esteban

    2016-04-15

    The aim of this study was to evaluate the presence and distribution of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs), concretely those so-called as dioxin-like PCBs, in yellow-legged gull eggs (Larus michahellis) collected from five Natural Parks (some of them National Parks) in Spain during the period 2010-2013. PCDD/Fs and dl-PCBs were detected in all the samples. Due to the proximity to important urban and industrial areas higher concentrations were determined in colonies located in the Northern Mediterranean coast than those found in the Southern Mediterranean or Atlantic colonies where a softer anthropogenic impact occurs. Mean ∑PCDD/F concentrations ranged from 49 to 223pg/g lipid weight (lw) and ∑dl-PCB concentrations varied from 146 to 911ng/g lw. In the Natural Park of the Ebro Delta (Northern Mediterranean coast) two gull species share habitat: yellow-legged and Audouin gull (Larus audouinii). Eggs from both species were collected and PCDD/F and dl-PCB levels compared. The species that feeds exclusively on pelagic fish (L. audouinii) had significantly higher PCDD/F and dl-PCB levels than the scavenger L. michahellis, pointing out the diet-dependent differences in the accumulation of persistent organic pollutants between similar cohabitant breeding species. Finally, mean TEQ values were in general below those considered as critical for toxicological effects in birds.

  6. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in seven different marine bird species from Iceland.

    PubMed

    Jörundsdóttir, Hrönn; Löfstrand, Karin; Svavarsson, Jörundur; Bignert, Anders; Bergman, Åke

    2013-11-01

    Data on distribution, concentration and trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) is scarce in biota from the sub-Arctic region of the Atlantic. The present study is an investigation on PBDE and HBCD concentrations in eggs from seven marine bird species from Iceland, i.e. common eider (Somateria mollissima), arctic tern (Sterna paradisaea), guillemot (Uria aalge), fulmar (Fulmarus glacialis), lesser black-backed gull (Larus fuscus), great black-backed gull (Larus marinus) and great skua (Stercorarius skua). Concentrations of sum PBDEs ranged from 44 ng g(-1)fat in eider eggs to 2400 ng g(-1)fat in great skua eggs. The contribution of different PBDE congeners to the sum concentration differed between species. Concentration of HBCDs (sum of α-,β(-) and γ-HBCD) ranged from 1.3 ng g(-1)fat in arctic tern eggs to 41 ng g(-1)fat in great black-backed gull. PCA on PBDE and HBCD shows different trends between the two BFR groups, further indicating different sources/usage. Investigations on any potential health or population effects of environmental pollutants on the great skua are advised since both the PBDE and HBCD concentrations are high.

  7. Natural Offshore Oil Seepage and Related Tarball Accumulation on the California Coastline - Santa Barbara Channel and the Southern Santa Maria Basin: Source Identification and Inventory

    USGS Publications Warehouse

    Lorenson, T.D.; Hostettler, Frances D.; Rosenbauer, Robert J.; Peters, Kenneth E.; Dougherty, Jennifer A.; Kvenvolden, Keith A.; Gutmacher, Christina E.; Wong, Florence L.; Normark, William R.

    2009-01-01

    Oil spillage from natural sources is very common in the waters of southern California. Active oil extraction and shipping is occurring concurrently within the region and it is of great interest to resource managers to be able to distinguish between natural seepage and anthropogenic oil spillage. The major goal of this study was to establish the geologic setting, sources, and ultimate dispersal of natural oil seeps in the offshore southern Santa Maria Basin and Santa Barbara Basins. Our surveys focused on likely areas of hydrocarbon seepage that are known to occur between Point Arguello and Ventura, California. Our approach was to 1) document the locations and geochemically fingerprint natural seep oils or tar; 2) geochemically fingerprint coastal tar residues and potential tar sources in this region, both onshore and offshore; 3) establish chemical correlations between offshore active seeps and coastal residues thus linking seep sources to oil residues; 4) measure the rate of natural seepage of individual seeps and attempt to assess regional natural oil and gas seepage rates; and 5) interpret the petroleum system history for the natural seeps. To document the location of sub-sea oil seeps, we first looked into previous studies within and near our survey area. We measured the concentration of methane gas in the water column in areas of reported seepage and found numerous gas plumes and measured high concentrations of methane in the water column. The result of this work showed that the seeps were widely distributed between Point Conception east to the vicinity of Coal Oil Point, and that they by in large occur within the 3-mile limit of California State waters. Subsequent cruises used sidescan and high resolution seismic to map the seafloor, from just south of Point Arguello, east to near Gaviota, California. The results of the methane survey guided the exploration of the area west of Point Conception east to Gaviota using a combination of seismic instruments. The

  8. Contrasting clonal structure among Pocillopora (Scleractinia) communities at two environmentally distinct sites in the Gulf of California

    NASA Astrophysics Data System (ADS)

    Pinzón, J. H.; Reyes-Bonilla, H.; Baums, I. B.; LaJeunesse, T. C.

    2012-09-01

    The contributions of sexual versus asexual reproduction are thought to play an important role in the abundance and ecological success of corals, especially in marginal habitats. Pocillopora corals are distributed throughout the Indo-Pacific and dominate shallow hard-bottom communities in the eastern Pacific where broad seasonal fluctuations in temperature and water turbidity create suboptimal conditions for reef community development. Previous work had revealed three genetic clades in the eastern Pacific that show little correspondence with colony morphology; the broad distribution of type 1 extends into the subtropical southern Gulf of California. Here we examine genetic and clonal structure of two type 1 communities separated by 10 km with microsatellite data. Samples were collected randomly in six 10 m radius circular plots (20 colonies per plot, 3 plots per site). Sites differed in their relative clonality because clonemates (ramets) from a single clone (genet) dominated a large portion (90.9 m long) of the protected leeward side of Gaviota Island (Number of genets/Number of samples = 0.35; observed Genotypic diversity/expected Genotypic diversity = 0.087), while an exposed community at the entrance to La Paz Bay, Punta Galeras, exhibited high genotypic diversity ( N g / N = 0.85; G o / G e = 0.714). Gene flow was unrestricted between sites indicating these communities comprised a single population. The relative proportion of asexual colonies found between community aggregations of Pocillopora in the Gulf of California differed significantly and suggests factors at local, not regional, scales affect these patterns. The possibility that heterogeneity in clonal structure is common throughout the eastern Pacific and across the west Indo-Pacific requires further study. Finally, since morphological variation in Pocillopora has been underappreciated and is in need of taxonomic revision, the use of a consistent field-sampling protocol and high-resolution makers will

  9. Root and shoot parts of strawberry: factories for production of functional human pro-insulin.

    PubMed

    Tavizi, Ashkan; Javaran, Mokhtar Jalali; Moieni, Ahmad; Mohammadi-Dehcheshmeh, Manijeh; Mohebodini, Mehdi; Ebrahimie, Esmaeil

    2015-05-01

    Diabetes, a disease caused by excessive blood sugar, is caused by the lack of insulin. For commercial production, insulin is made in bacteria or yeast by protein recombinant technology. The focus of this research is evaluating another resource and producing of recombinant insulin protein in as strawberry as this plant has high potential in production of pharmaceutical proteins. Strawberry is a suitable bioreactor for production of recombinant proteins especially edible vaccines. In this research, human pro-insulin gene was cloned in pCAMBIA1304 vector under CaMV35S promoter and NOS terminator. Agrobacterium tumefaciens LBA4404, AGL1, EHA105, EHA101, C58, C58 (pGV2260) and C58 (pGV3101) strains were used for transformation of pro-insulin gene into strawberry cv. Camarosa, Selva, Sarian Hybrid, Pajaro, Paros, Gaviota, Alpine. Additionally, Agrobacterium rhizogenes K599, R1000, A4 and MSU440 strains were utilized for gene transformation into hairy roots. PCR analysis indicated the presence of transformed human pro-insulin gene in the strawberry and hairy roots. Also, its transcription was confirmed using RT-PCR. Furthermore, the analysis of plants, fruits and hairy roots at the level of proteins using dot blot, ELISA, SDS-PAGE and ECL tests re-confirmed the expression of this protein in the transgenic plants as well as hairy roots. Protein purification of human pro-insulin from transgenic tissues was performed using affinity chromatography. Finally, the bioassay of recombinant pro-insulin was performed. The analysis of second generations of transgenic plants (T1) at DNA and protein levels was also performed as a complementary experiment. This study opens a new avenue in molecular farming of human pro-insulin through its mass production in roots and shoots of strawberry.

  10. Dynamic growth of slip surfaces in catastrophic landslides

    PubMed Central

    Germanovich, Leonid N.; Kim, Sihyun; Puzrin, Alexander M.

    2016-01-01

    This work considers a landslide caused by the shear band that emerges along the potential slip (rupture) surface. The material above the band slides downwards, causing the band to grow along the slope. This growth may first be stable (progressive), but eventually becomes dynamic (catastrophic). The landslide body acquires a finite velocity before it separates from the substrata. The corresponding initial-boundary value problem for a dynamic shear band is formulated within the framework of Palmer & Rice's (Proc. R. Soc. Lond. A 332, 527–548. (doi:10.1098/rspa.1973.0040)) approach, which is generalized to the dynamic case. We obtain the exact, closed-form solution for the band velocity and slip rate. This solution assesses when the slope fails owing to a limiting condition near the propagating tip of the shear band. Our results are applicable to both submarine and subaerial landslides of this type. It appears that neglecting dynamic (inertia) effects can lead to a significant underestimation of the slide size, and that the volumes of catastrophic slides can exceed the volumes of progressive slides by nearly a factor of 2. As examples, we consider the Gaviota and Humboldt slides offshore of California, and discuss landslides in normally consolidated sediments and sensitive clays. In particular, it is conceivable that Humboldt slide is unfinished and may still displace a large volume of sediments, which could generate a considerable tsunami. We show that in the case of submarine slides, the effect of water resistance on the shear band dynamics may frequently be limited during the slope failure stage. For a varying slope angle, we formulate a condition of slide cessation. PMID:26997904

  11. Dynamic growth of slip surfaces in catastrophic landslides.

    PubMed

    Germanovich, Leonid N; Kim, Sihyun; Puzrin, Alexander M

    2016-01-01

    This work considers a landslide caused by the shear band that emerges along the potential slip (rupture) surface. The material above the band slides downwards, causing the band to grow along the slope. This growth may first be stable (progressive), but eventually becomes dynamic (catastrophic). The landslide body acquires a finite velocity before it separates from the substrata. The corresponding initial-boundary value problem for a dynamic shear band is formulated within the framework of Palmer & Rice's (Proc. R. Soc. Lond. A332, 527-548. (doi:10.1098/rspa.1973.0040)) approach, which is generalized to the dynamic case. We obtain the exact, closed-form solution for the band velocity and slip rate. This solution assesses when the slope fails owing to a limiting condition near the propagating tip of the shear band. Our results are applicable to both submarine and subaerial landslides of this type. It appears that neglecting dynamic (inertia) effects can lead to a significant underestimation of the slide size, and that the volumes of catastrophic slides can exceed the volumes of progressive slides by nearly a factor of 2. As examples, we consider the Gaviota and Humboldt slides offshore of California, and discuss landslides in normally consolidated sediments and sensitive clays. In particular, it is conceivable that Humboldt slide is unfinished and may still displace a large volume of sediments, which could generate a considerable tsunami. We show that in the case of submarine slides, the effect of water resistance on the shear band dynamics may frequently be limited during the slope failure stage. For a varying slope angle, we formulate a condition of slide cessation.

  12. Morphology, acoustic characteristics, and Late Quaternary growth of conception Fan, Santa Barbara basin, California

    SciTech Connect

    Kraemer, S.M.C.

    1986-04-01

    A radial borderland-basin fan in the western half of the Santa Barbara basin, the Conception Fan, shows characteristics of a debris slope. More than 3000 mi of closely spaced (3.5 kHz) high-resolution profiles, 270 gravity cores, and 8 borings were used to map channel and fan morphology, and channel, levee, and lobe acoustic facies. Two major unconformities are recognized on the seismic profiles. The upper unconformity represents the 10-k.y.B.P. horizon. The lower unconformity is the erosional surface of the late Wisconsinan lowstand of sea level, 18-26 k.y.B.P. Eustasy and tectonism produced two pulses of deposition, each from a different point source, during the Flandrian transgression. Prior to the late Pleistocene, the Conception Fan was fed by one major canyon/channel system, above the western part of the fan. During the late Pleistocene, two small submarine canyons were cut into the slope 7 mi east. Four major channels, smaller than the western channel system, were incised into the fan surface, indicating the eustatic decrease in sediment input. The fault-controlled western canyon (Sacate) fed all but the eastern channel. Faulting and slumping on the slope cut the eastern canyon (Gaviota) and formed the eastern channel. Numerous slope gullies influenced eastern canyon and channel development. Holocene currents rounding Point Conception have winnowed fine sediments in the western channel region, resulting in hummocky topography and the scoured appearance of the channel. Hemipelagic deposition dominates the lower-middle and lower fan of the eastern part of the fan. The western part of the fan seems to be receiving slope-like deposits over the relict fan surface.

  13. Paleogene sequence stratigraphy of the Transverse Ranges, southern California

    SciTech Connect

    Campion, K.M.; Morgan, S.R.; Lohmar, J.M. )

    1990-05-01

    Integration of satellite data, high-altitude photos, well log correlation and field observations has been used to develop a sequence stratigraphic framework for Tertiary strata in the Transverse Ranges. The framework is based on tracing sequence boundaries or unconformities in the field, and on the ability to recognize these surfaces on well log data. Identification of parasequence stacking patterns that are typical of transgressive, highstand, and lowstand systems tracts was significant in building this framework. Systematic development of these stacking patterns was considered unlikely where local random events alone influenced deposition. Biostratigraphic data was tied to eustatic cycle charts to relate these sequences to global events. Key boundaries that were identified include the 49.5-, 48.5-, 44-, 39.5-, 36-, and 30-m.y. sequence boundaries. For example, the 49.5- and 48.5-m.y. sequence boundaries are located within the Matilija Formation. These sequences locally exhibit truncation and development of highstand, lowstand, and transgressive system tracts; lowstand and transgressive system tracts are best developed. The 39.5-m.y. sequence boundary is located between the Sacate and Gaviota formations in the western Transverse Ranges. This boundary exhibits tectonic enhancement on satellite photos with truncation of middle Eocene folds below the unconformity. Previously, abrupt lithologic changes across this unconformity were regarded as facies changes. Sequences within the Transverse Ranges exhibit variability in terms of systems tract preservation degree of truncation, and depositional setting. Identification of stratigraphic surfaces, unconformities and flooding surfaces, and repetitive stacking arrangement of strata is essential to development of a sequence framework. The ability to put a framework together in the Transverse Ranges indicates that both tectonic and eustatic events can be recognized.

  14. At-sea distribution and abundance of seabirds off southern California: A 20-year comparison

    USGS Publications Warehouse

    Mason, J.W.; McChesney, G.J.; McIver, W.R.; Carter, H.R.; Takekawa, John Y.; Golightly, R.T.; Ackerman, Joshua T.; Orthmeyer, D.L.; Perry, W.M.; Yee, J.L.; Pierson, M.O.; McCrary, M.D.

    2007-01-01

    We conducted aerial at-sea and coastal surveys to examine the distribution and abundance of seabirds off southern California, from Cambria, California, to the Mexican border. From May 1999-January 2002, we flew 102 d, covered >54,640 km of transect lines, and conducted nine complete surveys of southern California in January, May, and September. We identified 54 species comprising 12 families and counted >135,000 individuals. Seabird densities were greater along island and mainland coastlines than at sea and were usually greatest in January surveys. Densities were greatest at sea near the northern Channel Islands in January and north of Point Conception in May, and lowest in the southwestern portion of the Southern California Bight in all survey months. On coastal transects, seabird densities were greatest along central and southern portions of the mainland coastline from Point Arguello to Mexico. We estimated that 981,000 ?? 144,000 (x?? ?? SE) seabirds occurred in the study area in January, 862,000 ?? 95,000 in May, and 762,000 ?? 72,000 in September. California Gulls (Larus californicus), Western Grebes (Aechmophorus occidentalis), and Cassin's Auklets (Ptychoramphus aleuticus) were most abundant in January surveys at sea, whereas Sooty and Short-tailed shearwaters (Puffinus griseus and P. tenuirostris), phalaropes (Phalaropus spp.), and Western Gulls (Larus. occidentalis) were most abundant in May and September surveys. On coastal transects, California Gulls, Western Grebes, Western Gulls, and Surf Scoters (Melanitta perspicillata) were most abundant in January; Western Grebes, Western Gulls, Surf Scoters, and Brown Pelicans (Pelecanus occidentalis) were most abundant in May; and Sooty Shearwaters, Short-tailed Shearwaters, Western Gulls, Western Grebes, Brown Pelicans, and Heermann's Gulls (Larus heermanni) were most abundant in September. Compared to historical seabird densities collected in the same area two decades ago (1975-1978 and 1980-1983), abundance

  15. Dietary changes and poor reproductive performance in Glaucous-winged Gulls

    USGS Publications Warehouse

    Murphy, Edward C.; Day, Robert H.; Oakley, Karen L.; Hoover, A. Anne

    1984-01-01

    The breeding phenology of Glaucous-winged Gulls (Larus glaucescens) on Squab Island, Aialik Bay, Alaska in 1979 was identical to that in 1980, but clutch sizes and later reproductive performance differed markedly. In 1979, clutch sizes were small, but chick growth rates and survivorship were high. In contrast, clutch sizes were large in 1980, but chick growth rates were slow, and chick survivorship was extremely low. The different patterns of reproductive success appear to be related primarily to annual differences in foods utilized by adults. When adults fed primarily on blue mussels (Mytilus edulis), reproductive performance suffered, i.e. at the time of egg laying in 1979 and during the chick period in 1980. A switch to mussels from other prey types thus probably indicates a lack of availability of more suitable or preferred foods. Reproductive success at this colony appears to be strongly food limited; the timing of such limitation is not confined to a particular stage of reproduction.

  16. Haemagglutination-inhibiting activity to type A influenzaviruses in the sera of wild birds from the far east of the USSR

    PubMed Central

    Slepuškin, A. N.; Pysina, T. V.; Gonsovsky, F. K.; Sazonov, A. A.; Isačenko, V. A.; Sokolova, N. N.; Polivanov, V. M.; Lvov, D. K.; Zakstel'skaja, L. Ja.

    1972-01-01

    The discovery in migrating birds of influenzaviruses and the demonstration of relationships between strains found in man and in birds show the importance of these investigations for influenzavirus ecology. Investigation of birds in the far-east regions of the USSR is particularly important as many of them migrate to South-East Asia and China, the regions from which human influenza pandemics seem to originate. A total of 262 bird sera from these regions were titrated by the HI method with 20 different influenzavirus antigens (5 human, 2 equine, 1 swine, and 12 avian influenzaviruses). Haemagglutination-inhibiting activity was found in 16.8% of the tested sera, most frequently in sera of Anas formosa, Gallinago gallinago, Anas falcata, and Larus crassirostris. HI activity to A/turkey/Wisconsin/66 (Hav6N2) was found in 7.3% of the sera. PMID:4541006

  17. Analysis and visualization of animal movement.

    PubMed

    Shamoun-Baranes, Judy; van Loon, E Emiel; Purves, Ross S; Speckmann, Bettina; Weiskopf, Daniel; Camphuysen, C J

    2012-02-23

    The interdisciplinary workshop 'Analysis and Visualization of Moving Objects' was held at the Lorentz Centre in Leiden, The Netherlands, from 27 June to 1 July 2011. It brought together international specialists from ecology, computer science and geographical information science actively involved in the exploration, visualization and analysis of moving objects, such as marine reptiles, mammals, birds, storms, ships, cars and pedestrians. The aim was to share expertise, methodologies, data and common questions between different fields, and to work towards making significant advances in movement research. A data challenge based on GPS tracking of lesser black-backed gulls (Larus fuscus) was used to stimulate initial discussions, cross-fertilization between research groups and to serve as an initial focus for activities during the workshop.

  18. Infectious bursal disease virus antibodies in eider ducks and Herring Gulls

    USGS Publications Warehouse

    Hollmen, T.; Franson, J. Christian; Docherty, Douglas E.; Kilpi, Mikael; Hario, Martti; Creekmore, Lynn H.; Petersen, Margaret R.

    2000-01-01

    We measured antibodies to infectious bursal disease virus (IBDV) in blood of nesting Common Eider (Somateria mollissima) females and immature Herring Gulls (Larus argentatus) in the Baltic Sea, and in blood of Spectacled Eider (Somateria fischeri) females nesting in a remote area of western Alaska. Positive (??? 1:16) IBDV titers occurred in 75% of the eiders and 45% of the Herring Gull chicks. In eiders, the prevalence of positive titers differed among locations. We found no evidence that IBDV exposure impaired the immune function of Herring Gull chicks, based on their response to inoculation of sheep red blood cells. We suggest that eider ducks and Herring Gulls have been exposed to IBDV, even in locations where contact with poultry is unlikely. The presence of this virus in wild bird populations is of concern because it causes mortality of up to 30% in susceptible poultry.

  19. Influenza A virus in birds during spring migration in the Camargue, France.

    PubMed

    Lebarbenchon, Camille; Chang, Chung-Ming; van der Werf, Sylvie; Aubin, Jean-Thierry; Kayser, Yves; Ballesteros, Manuel; Renaud, François; Thomas, Frédéric; Gauthier-Clerc, Michel

    2007-10-01

    Wild aquatic birds are considered to be the natural reservoir for influenza A viruses, and previous studies have focused mainly on species in the orders Anseriformes and Charadriiformes. In this study, we surveyed a larger spectrum of potential hosts belonging to 10 avian orders. Cloacal swabs (n=1,044) from 72 free-living bird species, were analysed by reverse transcription-polymerase chain reaction for the presence of avian influenza virus. Only two Mediterranean Gulls (Larus melanocephalus) tested positive; one of these viruses was identified as an H9N2 subtype. The absence of infection among passerine birds supports the idea that the prevalence of avian influenza virus infection in terrestrial species is low.

  20. Contaminant levels in colonial waterbirds from Green Bay and Lake Michigan, 1975-80

    USGS Publications Warehouse

    Heinz, G.H.; Erdman, T.C.; Haseltine, S.D.; Stafford, C.

    1985-01-01

    Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated styrenes (PCSs), and mercury were measured in the eggs of 10 species of colonial waterbirds nesting in areas aroung Green Bay or Lake Michigan from 1975 to 1980. Residues also were measured in the carcasses and brains of black-crowned night-herons (Nycticorax nycticorax). The highest residues were of PCBs, DDE, mercury, and dieldrin; for some species, levels of these chemicals possibly were high enough to have caused reproductive effects. Other organochlorine pesticides were found at low levels. Only trace amounts of PCSs and PBBs were found. Eggs of herring gulls (Larus argentatus) collected in 1977 from an island in Lake Michigan contained an average of 100 ppm PCBs and 33 ppm DDE; this was the most- contaminated species. Cattle egrets (Bubulcus ibis), the only bird that is not a fish eater, contained only small quantities of DDE and mercury.

  1. Within clutch co-variation of egg mass and sex in the black-headed gull.

    PubMed

    Müller, W; Groothuis, T G G; Eising, C M; Daan, S; Dijkstra, C

    2005-05-01

    Female birds of several species have control over the production of daughters and sons. However, most studies failed to find a relationship between egg size and sex. This is intriguing as adjustment of egg size would constitute a powerful tool for the female to meet different resource demands of the sexes, particularly in size dimorphic species. Our results show that, within clutches of black-headed gulls (Larus ridibundus) the proportion of males was positively associated with egg mass. This applied for all three laying positions, independently of the absolute egg mass. There was a significant relationship between the distribution of the sexes over the laying sequence and the egg mass change. When egg mass decreased over the sequence, first-laid eggs were male biased and last-laid eggs female biased, and vice versa. The potential adaptive value of this allocation strategy is evaluated with regard to male sensitivity to egg quality and competitive differences between the sexes.

  2. Temporal changes in lead levels in common tern feathers in New York and relationship of field levels to adverse effects in the laboratory

    SciTech Connect

    Burger, J.; Lavery, M.H. ); Gochfeld, M. . Environmental and Occupational Health Sciences Inst. Robert Wood Johnson Medical School, Piscataway, NJ )

    1994-04-01

    In this paper the authors examine lead levels in the feathers of adult common terns (Sterna hirundo) from 1978 to 1992, compare them to values for other species breeding in the same or nearby colonies from one year (1989), and contrast these levels with those associated with sublethal behavioral and physiological effects in the lab. Lead levels in feathers of common tern decreased significantly from 1978 through 1985, were stable until 1988, and then increased through 1992. The mean levels of lead in feathers of roseate tern (Sterna dougallii), herring gull (Larus argentatus), and black skimmer (Rynchops niger) were slightly higher than those for common terns in 1989. Levels in feathers of some individuals of all species in the wild were within the range associated with behavioral impairment and growth retardation in the lab.

  3. Changes in prevalence and intensity of infection of Profilicollis altmani (Perry, 1942) cystacanth (Acanthocephala) parasitizing the mole crab Emerita analoga (Stimpson, 1857): an El Niño cascade effect?

    NASA Astrophysics Data System (ADS)

    Oliva, Marcelo E.; Barrios, Irene; Thatje, Sven; Laudien, Jürgen

    2008-03-01

    Prevalence and intensity changes in cystacanths of the acanthocephalan Profilicollis altmani parasitizing the mole crab Emerita analoga under El Niño (EN) and non-El Niño (non-EN) conditions are analyzed. Both, mean intensity and prevalence of infection by P. altmani differ significantly for the whole size range and for each size class of 10 mm intervals (except prevalence for size classes exceeding 18 mm carapace length) between EN (1998) and non-EN (2002) years, without observed size distribution differences in the intermediate host E. analoga under either condition. Significant difference in infestation rates of the intermediate host E. analoga is discussed as being an EN cascade effect on predators such as sea birds (i.e., Larus spp. and Calidris sp.), acting as definitive hosts of P. altmani, and which are known to decrease significantly in abundance during EN.

  4. Slaty-backed Gull in Sullivan Co., NY

    USGS Publications Warehouse

    Freer, V.; Haas, J.; Buckley, P.A.

    2002-01-01

    An adult Slaty-backed Gull (Larus schistisagus) was found and photographed at Neversink Reservoir, Sullivan Co., NY on 20 February 2002. A native of northeastern Eurasia and northern Japan, this species is rare along the Bering coast of Alaska, and there are only a handful of scattered records in the lower 48 state since the first in St Louis along the Mississippi River in late 1983. There is one previous New York State occurrence, in the Niagara River Gorge area of NY/ONT, 24 November-29 December 1992. The Sullivan Co. adult is the closest confirmed Slaty-backed Gull to the Atlantic Coast; recent single individuals along the Susquehanna River in MD, and at Cape Hatteras NC remain in dispute.

  5. Behaviorally Induced Camouflage: A New Mechanism of Avian Egg Protection.

    PubMed

    Mayani-Parás, Fernando; Kilner, Rebecca M; Stoddard, Mary Caswell; Rodríguez, Cristina; Drummond, Hugh

    2015-10-01

    When animals potentially occupy diverse microhabitats, how can camouflage be achieved? Here we combine descriptive and experimental methods to uncover a novel form of phenotypic plasticity in the camouflage of bird eggs that may be present in other avian taxa. Soil from the bare substrate adheres to the blue-footed booby's (Sula nebouxii's) pale eggs, which parents manipulate both under and on top of their webs. Analysis of digital images confirmed that dirtiness increases progressively during the first 16 days of the incubation period, making eggs more similar to the nest substrate. Observations of 3,668 single-egg clutches showed that the probability of egg loss declines progressively over the same time frame and then remains low for the rest of the 41-day incubation period. An experiment showed that when chicken eggs are soiled and exposed in artificial booby nests, they are less likely to be taken by Heermann's gulls (Larus heermanni) than clean eggs.

  6. California gull chicks raised near colony edges have elevated stress levels

    USGS Publications Warehouse

    Herring, Garth; Ackerman, Joshua T.

    2011-01-01

    Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers.

  7. Prevalence of Cryptosporidium species in wildlife populations within a watershed landscape in southeastern New York State.

    PubMed

    Ziegler, Peter E; Wade, Susan E; Schaaf, Stephanie L; Stern, David A; Nadareski, Christopher A; Mohammed, Hussni O

    2007-06-20

    A cross-sectional study was conducted to determine the prevalence of Cryptosporidium in wildlife in the New York City (NYC) Watershed in southeastern New York State. A total of 6227 fecal samples were collected and evaluated from 5892 mammals (38 species), 263 birds (14 species), 2 reptiles (2 species), 8 amphibians (4 species), and 62 fish (15 species). Cryptosporidium was detected in 30 species. Of the species found positive for Cryptosporidium, 16 represented new records for this parasite-Alosa pseudoharengus, Larus delawarensis, Blarina brevicauda, Sorex cinereus, Parascalops breweri, Myotis lucifugus, Peromyscus maniculatus, Microtus pennsylvanicus, Clethrionomys gapperi, Tamiasciurus hudsonicus, Marmota monax, Erethizon dorsatum, Canis latrans, Mustela erminea, Mustela vison, and Lynx rufus. Factors such as age, sex, season, and land use were evaluated to determine if there was any association with infection by this parasite. Animals were more likely to be positive for Cryptosporidium during spring and in agricultural land use.

  8. Prevalences of zoonotic bacteria among seabirds in rehabilitation centers along the Pacific Coast of California and Washington, USA.

    PubMed

    Steele, Christine M; Brown, Richard N; Botzler, Richard G

    2005-10-01

    Many seabirds are rehabilitated annually by wildlife rehabilitation centers along the Pacific Coast, USA. Although various strains of zoonotic bacteria have been isolated from seabirds, risks to rehabilitators at these centers have not been well documented. From November 2001 through January 2003, we determined the prevalence of detectable enteric fauna by isolation and characterization of Gram-negative bacteria from cloacal swabs taken from 26 common murres (Uria aalge), 49 gulls (Larus spp.), and 14 other seabirds treated by rehabilitators in California and Washington (USA). At least 25 bacterial species were identified, including multiple strains of Escherichia coli, as well as Enterobacter cloacae, Citrobacter freundii, and Klebsiella pneumoniae. Antibiotic resistance was found in 13 of 19 bacterial isolates tested, including E. coli, K. pneumoniae, Acinetobacter baumanii, and Pseudomonas aeruginosa. Potential transfer of these bacteria poses a risk to wildlife rehabilitators and to seabirds in these centers, as well as to free-ranging birds.

  9. Levels and temporal trends (1983-2003) of persistent organic pollutants (POPs) and mercury (Hg) in seabird eggs from Northern Norway.

    PubMed

    Helgason, Lisa B; Barrett, Rob; Lie, Elisabeth; Polder, Anuschka; Skaare, Janneche U; Gabrielsen, Geir W

    2008-09-01

    The main objective of this study was to investigate possible temporal trends of persistent organic pollutants (POPs) and mercury in eggs of herring gulls (Larus argentatus), black-legged kittiwakes (Rissa tridactyla), common guillemots (Uria aalge) and Atlantic puffins (Fratercula arctica) in Northern Norway. Eggs were collected in 1983, 1993 and 2003. Egg concentrations of POPs (PCB congeners IUPAC numbers: CB-28, 74, 66, 101, 99, 110, 149, 118, 153, 105, 141, 138, 187, 128, 156, 157, 180, 170, 194, 206, HCB, alpha-HCH, beta-HCH, gamma-HCH, oxychlordane, trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT) and mercury were quantified. Generally, POP levels decreased between 1983 and 2003 in all species. No significant temporal trend in mercury levels was found between 1983 and 2003.

  10. A juvenile-adult population model: climate change, cannibalism, reproductive synchrony, and strong Allee effects.

    PubMed

    Veprauskas, Amy; Cushing, J M

    2017-03-01

    We study a discrete time, structured population dynamic model that is motivated by recent field observations concerning certain life history strategies of colonial-nesting gulls, specifically the glaucous-winged gull (Larus glaucescens). The model focuses on mechanisms hypothesized to play key roles in a population's response to degraded environment resources, namely, increased cannibalism and adjustments in reproductive timing. We explore the dynamic consequences of these mechanics using a juvenile-adult structure model. Mathematically, the model is unusual in that it involves a high co-dimension bifurcation at [Formula: see text] which, in turn, leads to a dynamic dichotomy between equilibrium states and synchronized oscillatory states. We give diagnostic criteria that determine which dynamic is stable. We also explore strong Allee effects caused by positive feedback mechanisms in the model and the possible consequence that a cannibalistic population can survive when a non-cannibalistic population cannot.

  11. Uptake of /sup 226/Ra by established vegetation and black cutworm larvae, Agrotis ipsilon (class Insecta: order Lepidoptera), on U mill tailings at Elliot Lake, Canada

    SciTech Connect

    Clulow, F.V.; Dave, N.K.; Lim, T.P.; Cloutier, N.R.

    1988-07-01

    Radium-226 levels in samples from an inactive U tailings site at Elliot Lake, Ontario, Canada, were: 9140 +/- 500 mBq g-1 dry weight in the substrate; 62 +/- 1 mBq g-1 dry weight in rye, Secale cereale, and less than 3.7 mBq g-1 dry weight in oats, Avena sativa, the dominant species established by revegetation of the tailings; and 117 +/- 7 mBq g-1 dry weight in washed and unwashed black cutworm larvae. Concentration ratios were: vegetation to tailings 0.001-0.007; black cutworms to vegetation 3.6 and black cutworms to tailings 0.01. The values are considered too low to be considered a hazard to herring gulls, Larus argentatus, which occasionally feed on cutworms.

  12. Effects of introducing foxes and raccoons on herring gull colonies

    USGS Publications Warehouse

    Kadlec, J.A.

    1971-01-01

    Red foxes (Vulpes fulva) and raccoons (Procyon lotor) released at colonies of herring gulls (Larus argentatus) on islands off the Massachusetts coast effectively eliminated the production of young gulls. Annual predator introductions for 2-4 years caused major reductions in colony size and occasionally total abandonment of the island as a colony site. Observations of the experimental islands for 2 years after cessation of predator introductions showed slow repopulation of the islands and lower breeding success than on control islands. The size of the regional population was reduced largely because of the movements of gulls off the experimental islands. The introduced predators are, in most cases, difficult to maintain on the islands; this restricts their utility in population management.

  13. Effects of egg oiling on larid productivity and population dynamics

    USGS Publications Warehouse

    Lewis, S.J.; Malecki, R.A.

    1984-01-01

    In this study, oil was applied to naturally incubated great black-backed gull (Larus marinus) and herring gull (L. argentatus) eggs, and its effects on reproductive success were assessed. Embryo survival was inversely proportional to the quantity of petroleum applied to eggshell surfaces. Dose responses, however, were dependent on embryonic age at the time of treatment. Eggs of either species, treated with 10-20 mu l of No. 2 fuel oil 4-8 days after laying, experienced significant reductions in hatching success. Embryos oiled past the midpoint of the 28-day incubation period were insensitive to as much as 100 mu l of petroleum. Fuel oil weathered outdoors for several weeks was as toxic as fresh oil to larid embryos. Only under severe conditions (e.g., large doses of petroleum contaminating young embryos) could egg oiling have a significant impact upon populations of the herring gull and species with similar life-history characteristics.

  14. Uptake of 226Ra by established vegetation and black cutworm larvae, Agrotis ipsilon (class Insecta: order Lepidoptera), on U mill tailings at Elliot Lake, Canada.

    PubMed

    Clulow, F V; Davé, N K; Lim, T P; Cloutier, N R

    1988-07-01

    Radium-226 levels in samples from an inactive U tailings site at Elliot Lake, Ontario, Canada, were: 9,140 +/- 500 mBq g-1 dry weight in the substrate; 62 +/- 1 mBq g-1 dry weight in rye, Secale cereale, and less than 3.7 mBq g-1 dry weight in oats, Avena sativa, the dominant species established by revegetation of the tailings; and 117 +/- 7 mBq g-1 dry weight in washed and unwashed black cutworm larvae. Concentration ratios were: vegetation to tailings 0.001-0.007; black cutworms to vegetation 3.6 and black cutworms to tailings 0.01. The values are considered too low to be considered a hazard to herring gulls, Larus argentatus, which occasionally feed on cutworms.

  15. Effects of PCBs on liver ultrastructure and monooxygenase activities in Japanese quail

    SciTech Connect

    Stouvenakers, N.; Kremers, P.

    1996-05-01

    The effect of environmental pollutants such as PCBs and DDT on avian species is well documented. It is proven that chronic high level PCB intoxication perturbs calcium metabolism in birds, affecting eggshell thickness. PCBs have an impact on the liver. which accumulates high levels of toxicants. These induce drug-metabolizing enzyme activities in quail (Coturnix coturnix), herring gull (larus argentatus), and partridge (Prdix perdix). As these enzymes can degrade endogeneous molecules such as steroids, xenobiotics like PCBs can severely hinder birds` reproductive performance. PCBs induce damage such as regression of the testes, decreased sperm concentration, and altered embryonic development resulting in death or malformation of chicks. More ever, ultrastructural alterations linked with induction of these enzymes have been observed in the livers of PCB-contaminated chickens and ducks. This study examines the effects of Aroclor 1254 on liver morphology and glycogen content in quail, and related morphological modification to liver monoxygenase activities. 26 refs., 6 figs., 1 tab.

  16. Balancing predation and egg harvest in a colonial seabird: A simulation model

    USGS Publications Warehouse

    Zador, Stephani G.; Piatt, J.F.; Punt, A.E.

    2006-01-01

    We developed an individual-based model to study the effects of different regimes of harvesting eggs and natural predation on reproductive success in a colony of the glaucous-winged gull (Larus glaucescens) in Glacier Bay National Park, Alaska. The model incorporates the sequence of egg laying, relaying, and incubation to hatching for individual nests and calculates hatching success, incubation length, and the total number of eggs laid (as a result of re-nesting and relaying) in all nests in the colony. Stochasticity is incorporated in the distribution of nest lay dates, predation rates, and nests attacked during predation and harvest events. We estimated parameter values by fitting the model to data collected at a small colony during 1999 and 2000 using maximum likelihood. We then simulated harvests and analyzed model predictions. Model outputs indicate that harvesting early, and at one time, provides a predictable take of eggs with the least impact to gulls.

  17. Stable isotope analysis of temporal variation in the diets of pre-fledged Laughing Gulls

    USGS Publications Warehouse

    Knoff, A.J.; Macko, S.A.; Erwin, R.M.; Brown, K.M.

    2002-01-01

    The *13C, *15N, and *34S stable isotopic values of feathers from pre-fledged Laughing Gulls (Larus atricilla) in coastal Virginia and Jamaica Bay, New York were used to examine dietary variation during the nestling period. The tip portions of the feathers were used to indicate diet during the initiation of primary feather growth, whereas the base portions indicated diet during the period immediately prior to fledging. The results indicate that diets of the nestlings in Virginia moved to a higher trophic level during the period prior to fledging, however the New York nestlings did not appear to undergo any appreciable dietary change during this period. Overall, nestlings from both colonies consumed proportionately more foods of marine origin than freshwater or terrestrial. Therefore, the results do not support those of earlier studies that suggested that partially developed salt glands in young gulls might restrict the diet to more terrestrial or freshwater prey in the early stages of nestling growth.

  18. METAL LEVELS IN EGGS OF WATERBIRDS IN THE NEW YORK HARBOR (USA): TROPHIC RELATIONSHIPS AND POSSIBLE RISK TO HUMAN CONSUMERS

    PubMed Central

    Burger, Joanna; Elbin, Susan

    2015-01-01

    Health professionals are interested in evaluating the risks that heavy metals pose to eco-receptors and humans. The objective of this study was to examine levels of mercury (Hg), lead (Pb), cadmium (Cd), and other contaminants in waterbirds nesting in the New York harbor in 2012 to determine (1) whether there were species and locational differences, and (2) whether consumption of eggs posed a health risk to predators or humans. For arsenic (As), Pb, Hg, and selenium (Se), species contributed more to variations in levels than location; for Cd and chromium (Cr), location was more significant. Mean metal levels differed among species for all metals, except Cd. Highest levels were As (great black-backed gulls, Larus marinus), Cr (great egret, Ardea alba), Pb (Canada goose, Branta canadensis), and Hg and Se (black-crowned night heron, Nycticorax nycticorax). There were significant locational differences only for herring gulls (Larus argentatus); significant differences were found for all metals. Levels of Hg and Pb may be sufficiently high in eggs of some species to produce adverse effects in predators that eat them. The proportion of samples above 0.3 ppm Hg (U.S. Environmental Protection Agency [EPA] freshwater criteria for freshwater fish), the contaminant of health concern, ranged from 0% (Canada goose, great egret), to 14 and 27% in gulls, to 50% (black-crowned night heron). Some herring gull, great black-backed gull, and black-crowned night heron eggs had 0.5 ppm or higher Hg. Thus, human consumption of eggs may pose a risk to fetuses and young children. PMID:25424617

  19. Circulation of a Meaban-Like Virus in Yellow-Legged Gulls and Seabird Ticks in the Western Mediterranean Basin

    PubMed Central

    Cerdà-Cuéllar, Marta; Lecollinet, Sylvie; Pearce-Duvet, Jessica; Busquets, Núria; García-Bocanegra, Ignacio; Pagès, Nonito; Vittecoq, Marion; Hammouda, Abdessalem; Samraoui, Boudjéma; Garnier, Romain; Ramos, Raül; Selmi, Slaheddine; González-Solís, Jacob; Jourdain, Elsa; Boulinier, Thierry

    2014-01-01

    In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis), a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus), were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring the spatial and

  20. An evaluation of marine bird population trends following the Exxon Valdez oil spill, Prince William Sound, Alaska.

    PubMed

    Lance, B K; Irons, D B; Kendall, S J; McDonald, L L

    2001-04-01

    We examined post-spill trends (1989-1998) of marine bird populations in Prince William Sound (PWS) following the Exxon Valdez oil spill (EVOS) to evaluate recovery of injured taxa. Two criteria were employed. First, we examined population trends of injured taxa only in the oiled area of PWS using regression models. Second, we examined population trends of injured taxa in the oiled area relative to the unoiled area using homogeneity of the slopes tests. We considered a population recovering if there was a positive trend using either criteria. We considered a population not recovering if there was no trend using either criteria or a negative trend in the oiled area. A significant negative trend in the oiled area relative to the unoiled area was considered a continuing and increasing effect. Most taxa for which injury was previously demonstrated were not recovering and some taxa showed evidence of increasing effects nine years after the oil spill. Four taxa (loons Gavia spp, Harlequin Duck Histrionicus histrionicus, Bufflehead Bucephala spp, and North-western Crow Corvus caurinus) showed weak to very weak evidence of recovery. None of these taxa showed positive trends in both winter and summer. Nine taxa (grebes Podiceps spp, cormorants Phalacrocorax spp, Black Oystercatcher Haematopus bachmani, Mew Gull Larus canus, Glaucous-winged Gull Larus glaucescens, terns Sterna spp, murres Uria spp, Pigeon Guillemot Cepphus columba, and murrelets Brachyramphus spp) showed no evidence of recovery during summer or winter. Four taxa (scoters Melanitta spp, mergansers Mergus spp, goldeneyes Bucephala spp, and Black-legged Kittiwaka Rissa tridactyla) showed evidence of continuing, increasing effects. We showed evidence of slow recovery, lack of recovery, and divergent population trends in many taxa which utilize shoreline and nearshore habitats where oil is likely to persist. Potential lingering spill effects and natural variability appear to be acting in concert in delaying

  1. Circulation of a Meaban-like virus in yellow-legged gulls and seabird ticks in the western Mediterranean basin.

    PubMed

    Arnal, Audrey; Gómez-Díaz, Elena; Cerdà-Cuéllar, Marta; Lecollinet, Sylvie; Pearce-Duvet, Jessica; Busquets, Núria; García-Bocanegra, Ignacio; Pagès, Nonito; Vittecoq, Marion; Hammouda, Abdessalem; Samraoui, Boudjéma; Garnier, Romain; Ramos, Raül; Selmi, Slaheddine; González-Solís, Jacob; Jourdain, Elsa; Boulinier, Thierry

    2014-01-01

    In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis), a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus), were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring the spatial and

  2. Nest survival is influenced by parental behaviour and heterospecifics in a mixed-species colony

    USGS Publications Warehouse

    Brussee, Brianne E.; Coates, Peter S.; Hothem, Roger L.; Howe, Kristy; Casazza, Michael L.; Eadie, John M.

    2016-01-01

    Studies of avian nest success often focus on examining influences of variation in environmental and seasonal factors. However, in-depth evaluations can also incorporate variation in individual incubation behaviour to further advance our understanding of avian reproductive ecology. We examined these relationships in colonially nesting Black-crowned Night-Herons Nycticorax nycticorax using intensive video-monitoring methods to quantify incubation behaviours. We modelled nest survival as a function of both extrinsic factors and incubation behaviours over a 3-year period (2010–12) on Alcatraz Island, USA. Model-averaged parameter estimates indicated that nest survival increased as a function of greater incubation constancy (% of time spent incubating eggs within a 24-h period), and average daily precipitation throughout the nesting stage. Common Ravens Corvus corax are the only known nest predator of Night-Herons on Alcatraz Island, as on many other coastal Pacific islands. We also investigated the effects of heterospecific nesting of California Gulls Larus californicus and Western Gulls Larus occidentalis in a mixed-species colony with Night-Herons, based on nesting proximity data collected over a 2-year period (2011–12). This second analysis indicated that, in addition to incubation behaviours, nesting heterospecifics are an important factor for explaining variation in Night-Heron nest survival. However, contrary to our original expectation, we found that Night-Herons experienced increased nest survival with increasing distance from gull colony boundaries. These results may apply to other areas with multiple colonial nesting species and similar predator communities and climatic patterns.

  3. Changes in thyroid parameters of hatchling American kestrels (Falco sparverius) following embryonic exposure to technical short chain chlorinated paraffins (SCCPs; C10-13, 55.5% CL)

    USGS Publications Warehouse

    Fernie, Kimberly J; Henry, Paula F.; Letcher, Robert J; Palace, Vince; Peters, Lisa; Rattner, Barnett A.; Sverko, Edward; Karouna, Natalie

    2015-01-01

    Chlorinated paraffins (CPs) are complex mixtures of polychlorinated n-alkanes categorized according to their carbon chain length: short chain (SCCPs, C10 – C13), medium (C14 - C17), and long chain (C>17), chlorinated paraffins. SCCPs are primarily used in metalworking applications, as flame retardants, and in paints, adhesives, sealants, textiles, plastics and rubber (UNEP 2012). In 2012, the United Nations Environment Program (UNEP 2012) reported in the Revised Draft Risk Profile for SCCPs, that CPs were produced in the United States, the European Union (EU), Slovakia, Brazil, India, Japan and China. While annual global consumption of SCCPs is large (>25 tonnes/year), it has sharply declined over the past 20 years. SCCPs are released through wastewater, landfills, and air emissions (UNEP 2012). Concentrations of SCCPs have been reported in fish and marine mammals in North and South America, Europe, Japan, Greenland and the Arctic (UNEP 2012 and references therein). Characterization of SCCP concentrations and exposure in terrestrial wildlife is limited. In 2010, SCCP concentrations were reported in the eggs of yellow-legged gulls (Larus michahellis) (4536 ± 40 pg/g wet weight (ww)) and Audouin’s gulls (Larus audouinii) (6364 ± 20 pg/g ww) in Spain (Morales et al. 2012), and little auks (Alle alle) (5 - 88 ng/g ww) and kittiwakes (Rissa tridactyla) (5 - 44 ng/g ww) in the European Arctic (Reth et al. 2006). In Sweden, muscle of ospreys contained CPs of unspecified chain length (Jansson et al. 1993). Although the toxicity of SCCPs has been demonstrated in aquatic invertebrates, fish, frogs, and laboratory rats, there are limited avian studies and these reported no effects of SCCPs on egg parameters of domestic hens (Gallus gallus domesticus) and ducks (Anas platyrhynchos) (UNEP 2012). Despite reported accumulation of SCCPs in wild birds, to our knowledge, exposure-related toxicities and effects with respect to avian wildlife remain unknown.

  4. Metal pollution in biotic and abiotic samples of the Büyük Menderes River, Turkey.

    PubMed

    Durmaz, Emre; Kocagöz, Rasih; Bilacan, Evrim; Orhan, Hilmi

    2017-02-01

    The Büyük Menderes River (BMR) is one of the largest rivers in Turkey. This river irrigates efficient farmlands and includes tributaries of other rivers and streams and many populated towns within its limits in the Ege region. Both the estuary and Işıklı Lake serve as a sanctuary for various waterbirds. Therefore, the BMR plays a critical role both for the inhabitants and for the ecosystem organisms in its environs. In the present study, we analyzed levels of metals including iron, barium, zinc, vanadium, cobalt, chromium, cadmium, copper, nickel, aluminum, arsenic, manganese, antimony, silver, selenium, boron, mercury, titanium, and lead in river water, sediment, fish (Cyprinus carpio; common carp), and in various waterbird (Fulica atra, Euroasian coot; Larus michahellis, yellow-legged gull; Ardea cinerea, grey heron; Larus melanocephalus, Mediterranean gull; and Pelecanus crispus, pelican) samples. Analyses were performed using an inductively coupled plasma-mass spectrometry (ICP-MS) instrument after sample preparation. Comparing metal concentrations among different sample types, it was found that barium, aluminum, and zinc are the major metals in river water, and zinc in common carp muscle, while iron, aluminum, and manganese are the major metals in sediments. Iron, zinc, copper, and aluminum were the highest in waterbird muscle tissue. Iron and barium were found to be the major metals in eggshell, while iron and zinc are the major metals in egg samples. A simple "worst-case scenario" model of risk assessment revealed that some of the analyzed metals may pose a risk for human health through consuming fish.

  5. Identification of human enteric pathogens in gull feces at Southwestern Lake Michigan bathing beaches.

    PubMed

    Kinzelman, Julie; McLellan, Sandra L; Amick, Ashley; Preedit, Justine; Scopel, Caitlin O; Olapade, Ola; Gradus, Steve; Singh, Ajaib; Sedmak, Gerald

    2008-12-01

    Ring-billed (Larus delawarensis Ord, 1815) and herring (Larus argentatus Pontoppidan, 1763) gulls are predominant species of shorebirds in coastal areas. Gulls contribute to the fecal indicator burden in beach sands, which, once transported to bathing waters, may result in water quality failures. The importance of these contamination sources must not be overlooked when considering the impact of poor bathing water quality on human health. This study examined the occurrence of human enteric pathogens in gull populations at Racine, Wisconsin. For 12 weeks in 2004 and 2005, and 7 weeks in 2006, 724 gull fecal samples were examined for pathogen occurrence on traditional selective media (BBL CHROMagar-Salmonella, Remel Campy-BAP, 7% horse blood agar) or through the use of novel isolation techniques (Campylobacter, EC FP5-funded CAMPYCHECK Project), and confirmed using polymerase chain reaction (PCR) for pathogens commonly harbored in gulls. An additional 226 gull fecal samples, collected in the same 12-week period in 2004, from a beach in Milwaukee, Wisconsin, were evaluated with standard microbiological methods and PCR. Five isolates of Salmonella (0.7%), 162 (22.7%) isolates of Campylobacter, 3 isolates of Aeromonas hydrophila group 2 (0.4%), and 28 isolates of Plesiomonas shigelloides (3.9%) were noted from the Racine beach. No occurrences of Salmonella and 3 isolates of Campylobacter (0.4%) were found at the Milwaukee beach. A subset of the 2004 samples was also examined for Giardia and Cryptosporidium and was found to be negative. Information as to the occurrence of human pathogens in beach ecosystems is essential to design further studies assessing human health risk and to determine the parameters influencing the fate and transport of pathogens in the nearshore environment.

  6. Contaminant effects on Great Lakes' fish-eating birds: a population perspective

    USGS Publications Warehouse

    Heinz, G.H.; Kendall, Ronald J.; Dickerson, Richard L.; Giesy, John P.; Suk, William P.

    1998-01-01

    Preventing environmental contaminants from reducing wildlife populations is the greatest concern in wildlife toxicology. In the Great Lakes, environmental contaminants have a history of reducing populations of many species of fish-eating birds. Endocrine effects may have contributed to declines in fish-eating bird populations, but the overriding harm was caused by DDE-induced eggshell thinning. Toxic effects may still be occurring today, but apparently they are not of a sufficient magnitude to depress populations of most fish-eating birds. Once DDE levels in the Great Lakes declined, eggshells of birds began to get thicker and reproductive success improved. Populations of double-crested cormorants (Phalacrocorax auritus) and ring-billed gulls (Larus delawarensis) have increased dramatically since the bans on DDT and other organochlorine pesticides. Bald eagles (Haliaeetus leucocephalus) are still not reproducing at a normal rate along the shores of the Great Lakes, but success is much improved compared to earlier records when eggshell thinning was worse. Other species, such as herring gulls (Larus argentatus) and black-crowned night-herons (Nycticorax nycticorax), seem to be having improved reproductive success, but data on Great Lakes'-wide population changes are incomplete. Reproductive success of common terns (Sterna hirundo), Caspian terns (Sterna caspia), and Forster's terns (Sterna forsteri) seems to have improved in recent years, but, again, data on population changes are not very complete, and these birds face many habitat related problems as well as contaminant problems. Although contaminants are still producing toxic effects, and these effects may include endocrine disfunction, fish-eating birds in the Great Lakes seem to be largely weathering these effects, at least as far as populations are concerned. A lack of obvious contaminant effects on populations of fish-eating birds in the Great Lakes, however, should not be equated with a lack of any harm to

  7. Metal levels in eggs of waterbirds in the New York Harbor (USA): trophic relationships and possible risk to human consumers.

    PubMed

    Burger, Joanna; Elbin, Susan

    2015-01-01

    Health professionals are interested in evaluating the risks that heavy metals pose to eco-receptors and humans. The objective of this study was to examine levels of mercury (Hg), lead (Pb), cadmium (Cd), and other contaminants in waterbirds nesting in the New York harbor in 2012 to determine (1) whether there were species and locational differences, and (2) whether consumption of eggs posed a health risk to predators or humans. For arsenic (As), Pb, Hg, and selenium (Se), species contributed more to variations in levels than location; for Cd and chromium (Cr), location was more significant. Mean metal levels differed among species for all metals, except Cd. Highest levels were As (great black-backed gulls, Larus marinus), Cr (great egret, Ardea alba), Pb (Canada goose, Branta canadensis), and Hg and Se (black-crowned night heron, Nycticorax nycticorax). There were significant locational differences only for herring gulls (Larus argentatus); significant differences were found for all metals. Levels of Hg and Pb may be sufficiently high in eggs of some species to produce adverse effects in predators that eat them. The proportion of samples above 0.3 ppm Hg (U.S. Environmental Protection Agency [EPA] freshwater criteria for freshwater fish), the contaminant of health concern, ranged from 0% (Canada goose, great egret), to 14 and 27% in gulls, to 50% (black-crowned night heron). Some herring gull, great black-backed gull, and black-crowned night heron eggs had 0.5 ppm or higher Hg. Thus, human consumption of eggs may pose a risk to fetuses and young children.

  8. Hemosporidian blood parasites in seabirds—a comparative genetic study of species from Antarctic to tropical habitats

    NASA Astrophysics Data System (ADS)

    Quillfeldt, Petra; Martínez, Javier; Hennicke, Janos; Ludynia, Katrin; Gladbach, Anja; Masello, Juan F.; Riou, Samuel; Merino, Santiago

    2010-09-01

    Whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. Seabirds, in particular, are often free from blood parasites, even in the presence of potential vectors. By means of polymerase chain reaction, we amplified a DNA fragment from the cytochrome b gene to detect parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus in 14 seabird species, ranging from Antarctica to the tropical Indian Ocean. We did not detect parasites in 11 of these species, including one Antarctic, four subantarctic, two temperate, and four tropical species. On the other hand, two subantarctic species, thin-billed prions Pachyptila belcheri and dolphin gulls Larus scoresbii, were found infected. One of 28 thin-billed prions had a Plasmodium infection whose DNA sequence was identical to lineage P22 of Plasmodium relictum, and one of 20 dolphin gulls was infected with a Haemoproteus lineage which appears phylogenetically clustered with parasites species isolated from passeriform birds such as Haemoproteus lanii, Haemoproteus magnus, Haemoproteus fringillae, Haemoproteus sylvae, Haemoproteus payevskyi, and Haemoproteus belopolskyi. In addition, we found a high parasite prevalence in a single tropical species, the Christmas Island frigatebird Fregata andrewsi, where 56% of sampled adults were infected with Haemoproteus. The latter formed a monophyletic group that includes a Haemoproteus line from Eastern Asian black-tailed gulls Larus crassirostris. Our results are in agreement with those showing that (a) seabirds are poor in hemosporidians and (b) latitude could be a determining factor to predict the presence of hemosporidians in birds. However, further studies should explore the relative importance of extrinsic and intrinsic factors on parasite prevalence, in particular using phylogenetically controlled comparative analyses, systematic sampling and screening of vectors, and within-species comparisons.

  9. A Comparitive Analysis of the Influence of Weather on the Flight Altitudes of Birds.

    NASA Astrophysics Data System (ADS)

    Shamoun-Baranes, Judy; van Loon, Emiel; van Gasteren, Hans; van Belle, Jelmer; Bouten, Willem; Buurma, Luit

    2006-01-01

    Birds pose a serious risk to flight safety worldwide. A Bird Avoidance Model (BAM) is being developed in the Netherlands to reduce the risk of bird aircraft collisions. In order to develop a temporally and spatially dynamic model of bird densities, data are needed on the flight-altitude distribution of birds and how this is influenced by weather. This study focuses on the dynamics of flight altitudes of several species of birds during local flights over land in relation to meteorological conditions.We measured flight altitudes of several species in the southeastern Netherlands using tracking radar during spring and summer 2000. Representatives of different flight strategy groups included four species: a soaring species (buzzard ), an obligatory aerial forager (swift Apus apus), a flapping and gliding species (blackheaded gull Larus+ridibundus&search_kingdom=every&search_span=exactly_for&categories=All&source=html&search_credRating=All" TARGET='itis_window'>Larus ridibundus), and a flapping species (starling Sturnus vulgaris).Maximum flight altitudes varied among species, during the day and among days. Weather significantly influenced the flight altitudes of all species studied. Factors such as temperature, relative humidity, atmospheric instability, cloud cover, and sea level pressure were related to flight altitudes. Different combinations of factors explained 40% 70% of the variance in maximum flight altitudes. Weather affected flight

  10. Chlamydiaceae in North Atlantic Seabirds Admitted to a Wildlife Rescue Center in Western France

    PubMed Central

    Aaziz, R.; Gourlay, P.; Vorimore, F.; Sachse, K.; Siarkou, V. I.

    2015-01-01

    Birds are the primary hosts of Chlamydia psittaci, a bacterium that can cause avian chlamydiosis in birds and psittacosis in humans. Wild seabirds are frequently admitted to wildlife rescue centers (WRC) at European Atlantic coasts, for example, in connection with oil spills. To investigate the extent of chlamydial shedding by these birds and the resulting risk for animals in care and the medical staff, seabirds from a French WRC were sampled from May 2011 to January 2014. By use of a quantitative PCR (qPCR), 195 seabirds belonging to 4 orders, 5 families and 13 species were examined, of which 18.5% proved to be Chlamydiaceae positive. The highest prevalence of shedders was found in northern gannets (Morus bassanus) (41%), followed by European herring gulls (Larus argentatus) (14%) and common murres (Uria aalge) (7%). Molecular characterization and phylogenetic analysis of qPCR-positive northern gannet samples revealed two variants of a strain closely related to C. psittaci. In European herring gulls and in one common murre, strains showing high sequence similarity to the atypical Chlamydiaceae-like C122 previously found in gulls were detected. Our study shows that seabirds from the northeastern Atlantic Ocean carry several chlamydial organisms, including C. psittaci-related strains. The staff in WRCs should take protective measures, particularly in the case of mass admissions of seabirds. PMID:25934619

  11. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping.

    PubMed

    Navarro, Joan; Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps.

  12. Adrenocortical function of Arctic-breeding glaucous gulls in relation to persistent organic pollutants.

    PubMed

    Verboven, Nanette; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Evans, Neil P

    2010-03-01

    Unpredictable changes in the environment stimulate the avian hypothalamo-pituitary-adrenal axis to produce corticosterone, which induces behavioural and metabolic changes that enhance survival in the face of adverse environmental conditions. In addition to profound environmental perturbations, such as severe weather conditions and unpredictable food shortages, many Arctic-breeding birds are also confronted with chronic exposure to persistent organic pollutants (POPs), some of which are known to disrupt endocrine processes. This study investigated the adrenocortical function of a top predator in the Arctic marine environment, the glaucous gull (Larus hyperboreus). High concentrations of organochlorines, brominated flame retardants and metabolically-derived products in blood plasma of incubating glaucous gulls were associated with high baseline corticosterone concentrations in both sexes and a reduced stress response in males. Contaminant-related changes in corticosterone concentration occurred over and above differences in body condition and seasonal variation. Chronically high corticosterone concentrations and/or a compromised adrenocortical response to stress can have negative effects on the health of an individual. The results of the present study suggest that exposure to POPs may increase the vulnerability of glaucous gulls to environmental stressors and thus could potentially compromise their ability to adapt to the rapidly changing environmental conditions associated with climate change that are currently seen in the Arctic.

  13. Differential Annual Movement Patterns in a Migratory Species: Effects of Experience and Sexual Maturation

    PubMed Central

    Jorge, Paulo E.; Sowter, David; Marques, Paulo A. M.

    2011-01-01

    Some animals migrate long distances to exploit important seasonal food resources in the northern regions of the northern hemisphere, whilst avoiding winter starvation. Changes in the individual's age and navigational skills are likely to affect migration, which in turn influences the geographic distribution of individuals. Processes such as sexual maturation and navigational abilities are affected by age, and age is thus a key factor in understanding migration patterns and differences in distribution ranges. In the present study, we investigated the effects of age on the geographic distribution of a population of Lesser Black-backed Gulls Larus fuscus throughout its annual cycle, by analyzing a dataset of 19,096 records from 10,000 color-ringed gulls. In contrast to previous assumptions, the results showed that gulls were geographically segregated by age throughout the entire annual cycle, rather than showing a geographic age-related cline only in the wintering areas. This asymmetric distribution results from a reduction in the annual range of sexually mature gulls, and the differential distribution of mature and immature individuals (mature birds remained in more northern areas, compared to immature birds, throughout the annual cycle). Furthermore, although immature gulls travelled longer distances than adults, they initiated their fall migration with short movements, in contrast to adults that migrated using longer movements. The effects identified in this study explain the non-homogenous distribution of populations throughout the annual cycle, with wide implications for the development of effective human health policies and/or wildlife management strategies. PMID:21799853

  14. Seasonal variations in aldrin epoxidase (MFO) activity of yellow-legged herring gulls: the relationship to breeding and PCB residues

    SciTech Connect

    Fossi, C.; Leonzio, C.; Focardi, S.; Renzoni, A.

    1988-09-01

    The hepatic mixed function oxidases (MFO) constitute a defense mechanism which enables the organism to make xenobiotics more polar and thus render them more readily excretable. The degree of induction of this system is an expression of its exposure to xenobiotics, but it is also a function of endogenous physiological mechanisms. These two forms of induction may lead to mutual interference: foreign compounds may stimulate hepatic hydroxylation and affect the metabolism of steroid hormones; the later may in turn stimulate the activity of the MFO system favoring the degradation of the xenobiotics. Induction and detoxication processes of endogenous and exogenous compounds have been observed in mammals in laboratory experiments. Relationships between MRO activity, the reproductive cycle and variations in tissue levels of liposoluble xenobiotics, have been reported for marine organisms. In birds, seasonal variations of MFO levels have been observed, but the relationship between these enzyme variations and the levels of contaminants in the animal tissues has never been made clear. The authors aim to clarify this relationship by determining the levels of PCBs residues and aldrin epoxidase activities in Yellow-legged Herring gull (Larus cachinnans) specimens from different areas of Italy collected during two phases of the annual cycle, namely those of reproduction (spring) and of sexual inactivity (autumn). This species was chosen because of its wide distribution, its opportunistic feeding habits and its adaptive capacity in polluted environments.

  15. Tracking the History and Ecological Changes of Rising Double-Crested Cormorant Populations Using Pond Sediments from Islands in Eastern Lake Ontario.

    PubMed

    Stewart, Emily M; Michelutti, Neal; Shenstone-Harris, Sarah; Grooms, Christopher; Weseloh, Chip; Kimpe, Linda E; Blais, Jules M; Smol, John P

    2015-01-01

    In the Laurentian Great Lakes region, the double-crested cormorant (Phalacrocorax auritus) has seen a thousand-fold population increase in recent decades. These large colonies of birds now often conflict with socioeconomic interests, particularly due to perceived competition with fisheries and the destruction of terrestrial vegetation in nesting habitats. Here we use dated sediment cores from ponds on islands in eastern Lake Ontario that receive waste inputs from dense colonies of cormorants and ring-billed gulls (Larus delawarensis) to chronicle the population rise of these species and assess their long-term ecological impacts. Modern water chemistry sampling from these sites reveals drastically elevated nutrient and major ion concentrations compared to reference ponds not influenced by waterbirds. Geochemical tracers in dated sediment cores, particularly δ15N and chlorophyll-a concentrations, track waterbird influences over time. Fossil diatom assemblages were dominated by species tolerant of hyper-eutrophic and polluted systems, which is in marked contrast to assemblages in reference sites. In addition to establishing long-term ecological impacts, this multi-proxy paleoecological approach can be used to determine whether islands of concern have been long-term nesting sites or were only recently colonized by cormorant or ring-billed gull populations across the Great Lakes, facilitating informed management decisions about controversial culling programs.

  16. Contaminant exposure of birds nesting in Green Bay, Wisconsin, USA.

    PubMed

    Custer, Thomas W; Dummer, Paul M; Custer, Christine M; Franson, J Christian; Jones, Michael

    2014-08-01

    In earlier studies, elevated concentrations of polychlorinated biphenyl (PCB) and p,p'-dichlorodiphenyldichloroethylene (DDE) were reported in double-crested cormorant (Phalacrocorax auritus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings collected from lower Green Bay (WI, USA) in 1994 and 1995 and black-crowned night-heron (Nycticorax nycticorax) eggs collected in 1991. Comparable samples collected in 2010 and 2011 indicated that concentrations of PCBs were 35%, 62%, 70%, and 88% lower than in the early 1990s in tree swallow eggs, tree swallow nestlings, double-crested cormorant eggs, and black-crowned night-heron eggs, respectively; concentrations of DDE were 47%, 43%, 51%, and 80% lower, respectively. These declines are consistent with regional contaminant trends in other species. Concentrations of PCBs were higher in herring gull (Larus argentatus) than in black-crowned night-heron eggs collected from Green Bay in 2010; PCB concentrations in double-crested cormorant and tree swallow eggs were intermediate. The estimated toxicity of the PCB mixture in eggs of the insectivorous tree swallow was the equal to or greater than toxicity in the 3 piscivorous bird species. A multivariate analysis indicated that the composition percentage of lower-numbered PCB congeners was greater in eggs of the insectivorous tree swallow than in eggs of the 3 piscivorous species nesting in Green Bay. Dioxin and furan concentrations and the toxicity of these chemicals were also higher in tree swallows than these other waterbird species nesting in Green Bay.

  17. Microsatellites identify depredated waterfowl remains from glaucous gull stomachs

    USGS Publications Warehouse

    Scribner, K.T.; Bowman, Timothy D.

    1998-01-01

    Prey remains can provide valuable sources of information regarding causes of predation and the species composition of a predator's diet. Unfortunately, the highly degraded state of many prey samples from gastrointestinal tracts often precludes unambiguous identification. We describe a procedure by which PCR amplification of taxonomically informative microsatellite loci were used to identify species of waterfowl predated by glaucous gulls (Larus hyperboreus). We found that one microsatellite locus unambiguously distinguished between species of the subfamily Anserinae (whistling ducks, geese and swans) and those of the subfamily Anatidae (all other ducks). An additional locus distinguished the remains of all geese and swan species known to nest on the Yukon-Kuskokwim delta in western Alaska. The study focused on two waterfowl species which have experienced precipitous declines in population numbers: emperor geese (Chen canagica) and spectacled eiders (Somateria fischeri). No evidence of predation on spectacled eiders was observed. Twenty-six percent of all glaucous gull stomachs examined contained the remains of juvenile emperor geese.

  18. Contaminant exposure of birds nesting in Green Bay, Wisconsin, USA

    USGS Publications Warehouse

    Custer, Thomas W.; Dummer, Paul M.; Custer, Christine M.; Franson, J. Christian; Jones, Michael

    2014-01-01

    In earlier studies, elevated concentrations of polychlorinated biphenyl (PCB) and p,p'-dichlorodiphenyldichloroethylene (DDE) were reported in double-crested cormorant (Phalacrocorax auritus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings collected from lower Green Bay (WI, USA) in 1994 and 1995 and black-crowned night-heron (Nycticorax nycticorax) eggs collected in 1991. Comparable samples collected in 2010 and 2011 indicated that concentrations of PCBs were 35%, 62%, 70%, and 88% lower than in the early 1990s in tree swallow eggs, tree swallow nestlings, double-crested cormorant eggs, and black-crowned night-heron eggs, respectively; concentrations of DDE were 47%, 43%, 51%, and 80% lower, respectively. These declines are consistent with regional contaminant trends in other species. Concentrations of PCBs were higher in herring gull (Larus argentatus) than in black-crowned night-heron eggs collected from Green Bay in 2010; PCB concentrations in double-crested cormorant and tree swallow eggs were intermediate. The estimated toxicity of the PCB mixture in eggs of the insectivorous tree swallow was the equal to or greater than toxicity in the 3 piscivorous bird species. A multivariate analysis indicated that the composition percentage of lower-numbered PCB congeners was greater in eggs of the insectivorous tree swallow than in eggs of the 3 piscivorous species nesting in Green Bay. Dioxin and furan concentrations and the toxicity of these chemicals were also higher in tree swallows than these other waterbird species nesting in Green Bay.

  19. Glaucous gull predation of goslings on the Yukon-Kuskokwim Delta, Alaska

    USGS Publications Warehouse

    Bowman, Timothy D.; Stehn, R.A.; Scribner, K.T.

    2004-01-01

    Glaucous Gulls (Larus hyperboreus) nesting on the Yukon-Kuskokwim (Y-K) Delta frequently prey on juvenile waterfowl. We collected 434 Glaucous Gulls from late June to early August 1994 to examine diet. Identification of undigested prey tissue, based on DNA microsatellite loci, showed three species of goslings in gull stomachs: Emperor Goose (Chen canagica), White-fronted Goose (Anser albifrons), and Cackling Canada Goose (Branta canadensis minima). Gulls that nested inland and were collected > 1.6 km from the coast accounted for approximately 70% of the total gull predation on Emperor and Canada Geese, and 96% on White-fronted Geese. Our stratified sample of gull stomachs and aerial survey estimates of population size and distribution of gulls and juvenile geese enabled extrapolation of species-specific predation rates to the entire Y-K Delta. We estimated that a minimum of 21 000 Emperor Goose, 34 000 Canada Goose, and 16 000 White-fronted Goose goslings were consumed by 12 600 Glaucous Gulls during the brood-rearing period on the Y-K Delta in 1994. Minimum estimated take by gulls represented 33% of Cackling Canada Goose, 47% of Emperor Goose, and 39% of White-fronted Goose eggs estimated to have hatched in the same area as gull collections. Gulls selected the three species of geese approximately in proportion to their abundance. Although gull predation caused significant gosling mortality, its role in regulating goose populations on Y-K Delta remains unresolved.

  20. Susceptibility of North American ducks and gulls to H5N1 highly pathogenic avian influenza viruses.

    PubMed

    Brown, Justin D; Stallknecht, David E; Beck, Joan R; Suarez, David L; Swayne, David E

    2006-11-01

    Since 2002, H5N1 highly pathogenic avian influenza (HPA1) viruses have been associated with deaths in numerous wild avian species throughout Eurasia. We assessed the clinical response and extent and duration of viral shedding in 5 species of North American ducks and laughing gulls (Larus atricilla) after intranasal challenge with 2 Asian H5N1 HPAI viruses. Birds were challenged at approximately equal to 10 to 16 weeks of age, consistent with temporal peaks in virus prevalence and fall migration. All species were infected, but only wood ducks (Aix sponsa) and laughing gulls exhibited illness or died. Viral titers were higher in oropharyngeal swabs than in cloacal swabs. Duration of viral shedding (1-10 days) increased with severity of clinical disease. Both the hemagglutination-inhibition (HI) and agar gel precipitin (AGP) tests were able to detect postinoculation antibodies in surviving wood ducks and laughing gulls; the HI test was more sensitive than the AGP in the remaining 4 species.

  1. Nutrient transfer from sea to land: the case of gulls and cormorants in the Gulf of Maine.

    PubMed

    Ellis, Julie C; Fariña, Jose Miguel; Witman, Jon D

    2006-03-01

    1. The structure of communities is influenced by the transport of resources across ecosystem boundaries. Seabirds are capable of introducing large amounts of marine-derived nutrients to land, thereby modifying resource availability to terrestrial species. 2. In this study we investigated the hypothesis that variation in nesting densities of great black-backed gulls Larus marinus and double-crested cormorants Phalacrocorax auritus would modify the effect of these species on soil nutrients and plant species composition on offshore islands in the Gulf of Maine, USA. 3. Our results showed a significant positive correlation between nest density and concentrations of ammonia and nitrate in soils, but no significant relationship between nest density and phosphate. Ammonia and phosphate concentrations were good predictors of plant species composition; there were more annual forbs than perennial grasses in the abandoned cormorant colony compared with the gull colonies. Extremely high concentrations of ammonia in the highest density colony (active cormorant) may have been the main factor inhibiting plant germination at this site. All of the plant species in gull and cormorant colonies showed enriched delta(15)N signatures, indicating substantial input of marine-derived nitrogen from seabirds. 4. Our study demonstrated that gulls and cormorants are effective vectors for the transport of marine nutrients to terrestrial ecosystems. However, transported nutrients occurred in particularly high concentrations in areas with nesting cormorants. Nesting densities and species-specific variation in resource transport should be considered when predicting the effects of seabirds and other biogenic vectors of allochthonous resources.

  2. Automatic recognition of harmonic bird sounds using a frequency track extraction algorithm.

    PubMed

    Heller, Jason R; Pinezich, John D

    2008-09-01

    This paper demonstrates automatic recognition of vocalizations of four common bird species (herring gull [Larus argentatus], blue jay [Cyanocitta cristata], Canada goose [Branta canadensis], and American crow [Corvus brachyrhynchos]) using an algorithm that extracts frequency track sets using track properties of importance and harmonic correlation. The main result is that a complex harmonic vocalization is rendered into a set of related tracks that is easily applied to statistical models of the actual bird vocalizations. For each vocalization type, a statistical model of the vocalization was created by transforming the training set frequency tracks into feature vectors. The extraction algorithm extracts sets of frequency tracks from test recordings that closely approximate harmonic sounds in the file being processed. Each extracted set in its final form is then compared with the statistical models generated during the training phase using Mahalanobis distance functions. If it matches one of the models closely, the recognizer declares the set an occurrence of the corresponding vocalization. The method was evaluated against a test set containing vocalizations of both the 4 target species and 16 additional species as well as background noise containing planes, cars, and various natural sounds.

  3. Hepatic cytochrome P450 activity and pollutant concentrations in paradise shelducks and southern black-backed gulls in the South Island of New Zealand.

    PubMed

    Numata, Mihoko; Fawcett, J Paul; Saville, Dorothy J; Rosengren, Rhonda J

    2008-11-01

    Cytochrome P450 (CYP) enzymes catalyse the oxidative metabolism of various xenobiotics including environmental pollutants. We investigated liver microsomal CYP marker activities in 60 paradise shelducks (Tadorna variegata; herbivore) and 77 southern black-backed gulls (Larus dominicanus; omnivore) collected at three sites with putatively different levels of pollution in the South Island of New Zealand. Ethoxyresorufin O-deethylase (EROD) activity was high in birds at an urban landfill site compared to those at a relatively pristine and an agricultural site. Analysis of p-nitrophenol hydroxylase and erythromycin demethylase activities indicated the presence of two additional CYP isoforms in shelducks but no additional form in gulls. Total polychlorinated biphenyl (PCB) concentrations (ranges: shelducks, 0.073-6.2; gulls, 8.2-330 ng/g wet weight) were high in landfill samples suggesting a link to EROD induction and, in landfill shelducks, EROD was independently associated with Hg and Pb concentration. PCB congener-specific assessments indicated the metabolism of at least two congeners (#28 and #74) is induced in shelducks. DDE concentrations (ranges: shelducks, 0.85-320; gulls, 44-4800 ng/g) were high in birds at the landfill and agricultural sites. Body weight tended to be lower in landfill birds, but whether this reflects the greater energetic demands of pollutant detoxification remains to be investigated.

  4. Distribution and abundance of marine bird and pinniped populations within Port Foster, Deception Island, Antarctica

    NASA Astrophysics Data System (ADS)

    Kendall, Katrina A.; Ruhl, Henry A.; Wilson, Robert C.

    2003-06-01

    Seabirds and pinnipeds were surveyed during four cruises from March 1999 to November 2000 at Port Foster, Deception Island, Antarctica. Abundances and distributions of three species of pinnipeds, Arctocephalus gazella (Antarctic fur seals), Leptonychotes weddelli (Weddell seals), and Lobodon carcinophagus (crabeater seals), and 11 species of marine birds were documented within Port Foster. A. gazella was the dominant pinniped within Port Foster; its abundance has increased since the 1986/87 austral summer season. A. gazella were concentrated at the entrance to Port Foster. More pinnipeds were observed during the austral summer than during the spring. The most dominant seabird, Pygoscelis antarctica (chinstrap penguin), was concentrated along the rocky cliffs behind the beaches where A. gazella hauled out. Larus dominicanus (kelp gull) and Daption capense (cape petrel) were the most dominant flying seabirds. All other seabird species were more widely distributed around Port Foster than P. antarctica. There was no clear trend in abundances of seabirds over the study period. It is possible that the protected area of Port Foster provides refuge for vagrants of colonies along the outer periphery of the island and as a stopover point for migrating species.

  5. Bottom-Up Control of Macrobenthic Communities in a Guanotrophic Coastal System

    PubMed Central

    Signa, Geraldina; Mazzola, Antonio; Costa, Valentina; Vizzini, Salvatrice

    2015-01-01

    Soft bottom macrobenthic communities were studied seasonally in three coastal ponds (Marinello ponds, Italy) at increasing distances from a gull (Larus michahellis) colony to investigate the effect of seabird-induced eutrophication (i.e. guanotrophication) on macrobenthic fauna. We hypothesized that enhanced nutrient concentration and organic load caused by guano input significantly alter the trophic and sedimentological condition of ponds, affecting benthic fauna through a bottom-up control. The influence of a set of environmental features on macrobenthic assemblages was also tested. Overall, the lowest macrobenthic abundances and functional group diversity were found in deeper sites, especially in the pond characterised by severe guanotrophication, where the higher disturbance resulted in a decline in suspension feeders and carnivores in favour of deposit feeders. An increase in opportunistic/tolerant taxa (e.g. chironomid larvae and paraonids) and totally azoic sediments were also found as an effect of the harshest environmental conditions, resulting in a very poor ecological status. We conclude that macrobenthic assemblages of the Marinello coastal system display high spatial variability due to a synergistic effect of trophic status and the geomorphological features of the ponds. The macrobenthic response to guanotrophication, which was a clear decrease in abundance, diversity and trophic functional groups, was associated with the typical response to severe eutrophication, magnified by the geomorphological features. PMID:25679400

  6. Nest-density distribution patterns in a yellow-legged gull archipelago colony

    NASA Astrophysics Data System (ADS)

    Vidal, Eric; Roche, Philip; Bonnet, Véronique; Tatoni, Thierry

    2001-12-01

    The nest density distribution of yellow-legged gulls Larus cachinnans was investigated on the large Marseille archipelago colony (south-east France) which houses c. 18 000 breeding pairs. The study was performed at two investigation scales, including both mean nesting density on the nine study islands and density distribution within 171 sampling plots. The mean nesting density on each island was negatively correlated with island surface area and with the distance from the initial colony location (south-east end of the archipelago). No significant correlation was found with the other island parameters analysed (maximum elevation, shape index and distance from continent). A partial least squares regression performed between denstiy data from 171 500 m 2 sampling plots and environmental variables showed that the mostly explaining factors were island isolation and percentage of rocks in the plots (positive correlation), and distance of the island from the south-east end of the archipelago, island area, distance from plot to seaside and percentage of stone in the plots (negative correlation). Thus in our case, vegetation parameters (cover and height) were not influencial factors in nest density distribution.

  7. What`s normal?: Body condition in Great Lakes herring gulls

    SciTech Connect

    Hebert, C.E.; Shutt, J.L.

    1994-12-31

    The Canadian Wildlife Service`s herring gull (Larus argentatus) surveillance program has demonstrated the usefulness of this species as a monitor of spatial and temporal trends in contaminant levels. However, the effects of environmental contaminants on gulls are difficult to distinguish from the effects of other anthropogenic stressors such as the introduction of exotic species, overfishing and habitat loss. To understand the relative importance of these factors in regulating the success of individual gulls and, hence, gull populations, the authors must first have a better understanding of what constitutes a ``normal`` bird. Improving the ability to differentiate between normal and abnormal birds is crucial in any health assessment of Great Lakes gulls. Body condition has been shown to be an important measure of a bird`s ability to provide energy for egg production, migration etc. Numerous approaches have been used to assess condition, most of which required that the bird be sacrificed. In this study, the authors describe a nonlethal technique to quantify body condition in herring gulls. Multivariate statistics are used to quantify body size, relate body size to total mass and from that, determine relative body condition. Initially, body condition is assessed in gulls from a reference colony where reproductive success is normal and anthropogenic influences are limited. This reference population is then used as a baseline against which other gull populations are compared.

  8. Seasonal movements, migration, and range sizes of subadult and adult Bamforth Lake California Gulls

    USGS Publications Warehouse

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

    1999-01-01

    We investigated seasonal migration patterns of three age classes of California Gulls (Larus californicus). Using band recovery data and reported sightings of patagially marked gulls, we constructed location maps for fledglings, one to two-year-old gulls, and breeding-age adult gulls during five time periods: spring migration, breeding season, early and late fall migration, and winter. Using repeated observations, we also produced a location map with directional vector plots. Gulls followed a triangular pattern of movements. At the conclusion of breeding, gulls migrated west and northwest to the Pacific coast, distributing themselves mainly between San Francisco and British Columbia. During winter, gulls moved south along the Pacific coast and by spring were concentrated in southern California and northern Mexico. The range size was largest among fledgings which provided the northernmost and southernmost observations for the population. Few subadult gulls migrated to the breeding colony. During the breeding season, a substantial portion of breeding-aged adults remained on the Pacific coast and throughout the intermountain west but were not observed at other California gull colonies. While fledgings moved directly toward the Pacific coast at the end of the breeding season, many adults lingered near the colony site at aquatic habitats south of the colony. We suggest that adults remain longer in the area to feed and to rejuvenate before attempting migration.

  9. [The taxonomy of the Baku virus (BAKV; Reoviridae, Orbivirus) isolated from the birds obligate parasites Argasidae ticks in Azerbaijan, Turkmenistan, and Uzbekistan].

    PubMed

    Al'khovskiĭ, S V; L'vov, D K; Shchelkanov, M Iu; Shchetinin, A M; Deriabin, P G; Gitel'man, A K; Botikov, A R; Samokhvalov, E I

    2013-01-01

    The Baku virus (BAKV) was originally isolated from the ticks Ornithodoros capensis Neumann, 1901 (Acari: Argasidae) collected from the seagull (Larus argentatus) seating nests on the islands of the Baku archipelago, the Caspian sea. BAKV was assigned to Kemerovo group (KEMV) (Orbivirus, Reoviridae). The BAKV was frequently isolated from the ticks O. coniceps Canestrini, 1980, collected from L. argentatus and tern (Sterna hirundo) nests in Turkmenia and pigeon (Columba livia neglecta) nests in Uzbekistan. In this work, the genome of the BAKV was sequenced using the next-generation sequencing technology. The BAKV Pol protein has 48.6% identity level with the viruses of the Great Island Virus group and at average 41% with non-tick orbiviruses. The BAKV T2 protein level identity with the orbiviruses ranges from 23.7% to 64.8%. The maximum identity level of the T2 protein (64.8%) is observed for the tick-borne viruses of the GIV (KEMV) group. According to the conducted molecular-genetic and phylogenetic analysis, the BAKV is a novel species of the genus Orbivirus. It forms a phylogenetic group distinctly related to the GIV group.

  10. Changes in the nesting populations of colonial waterbirds in Jamaica Bay Wildlife Refuge, New York, 1974-1998

    USGS Publications Warehouse

    Brown, K.M.; Tims, J.L.; Erwin, R.M.; Richmond, M.E.

    2001-01-01

    The Jamaica Bay Wildlife Refuge (JBWR) represents the largest protected area for over 300 species of migratory and resident birds on Long Island (LI), New York, and occupies a key position along the Atlantic flyway. We identified changes in nesting populations for 18 species of colonial waterbirds in JBWR and on LI, during 1974 - 1998, to provide a basis for future wildlife management decisions in JBWR and also at nearby John F. Kennedy International Airport. None of the populations was stable over the past 25 years in JBWR or on LI. Some populations in JBWR increased (Laughing Gull L. atricilla Linnaeus, Great Black-backed Gull L. marinus Linnaeus, Forster's Tern Sterna forsteri Nuttall) while others decreased (Herring Gull Larus argentatus Coues, Snowy Egret Egretta thula Molina), but only Cattle Egrets (Bubulcus ibis Linnaeus) have disappeared from the refuge. Common Tern (S. hitundo Linnaeus), Least Tern (S. antillarum Lesson), Roseate Tern (S. dougallii Montagu), Black Skimmer (Rynchops niger Linnaeus), Black-crowned Night Heron (Nycticorax nycticorax Linnaeus) and Great Egret (Ardea alba Linnaeus) populations all increased on LI over the sampling period although the Common Tern colonies in JBWR have been declining since 1986. The continued protection of the colony sites, particularly saltmarsh islands, in JBWR will be important to the conservation efforts of many colonial waterbird populations on Long Island. The JBWR colonies may serve as a source of emigrants to other Long Island colonies, and in some cases, act as a 'sink' for birds immigrating from New Jersey and elsewhere.

  11. Steroids for free? No metabolic costs of elevated maternal androgen levels in the black-headed gull.

    PubMed

    Eising, Corine M; Visser, G Henk; Müller, Wendt; Groothuis, Ton G G

    2003-09-01

    Within- and between-clutch variation in yolk titres of hormones of maternal origin has been found in many avian species. So far, experiments have revealed mainly beneficial effects of maternal androgens. This would also apply to black-headed gulls (Larus ridibundus). Previous experiments have shown that chicks benefit from these higher levels since their competitive abilities are improved and growth and survival probabilities thus enhanced. However, not all females show the same increase in yolk hormones from first to last egg or invest equally high amounts of androgens in their clutches. Possibly, there is a trade-off between the beneficial effects of high androgen levels and potential costs, such as increased metabolic rates. We studied possible metabolic costs of experimentally elevated yolk androgen levels for chicks of several age classes, starting three days prior to hatching until fledging at an age of approximately 30 days. Daily energy expenditure in the field, measured using the doubly labelled water technique, did not differ between treatments or between sexes. Oxygen consumption measured in birds at rest in the lab (RMR) did not vary between chicks hatched from androgen-injected (T) or oil-injected (Oil) control eggs at any age in thermo-neutral or below thermo-neutral conditions. Males showed a lower RMR than females towards the fledging age. We conclude that it is unlikely that the costs of high maternal androgen levels can be found in higher energy expenditure in the chick.

  12. Prenatal androgen exposure modulates cellular and humoral immune function of black-headed gull chicks.

    PubMed

    Müller, Wendt; Groothuis, Ton G G; Kasprzik, Alice; Dijkstra, Cor; Alatalo, Rauno V; Siitari, Heli

    2005-09-22

    Avian eggs contain considerable amounts of maternal yolk androgens, which have been shown to beneficially influence the physiology and behaviour of the chick. As androgens may suppress immune functions, they may also entail costs for the chick. This is particularly relevant for colonial species, such as the black-headed gull (Larus ridibundus), in which the aggregation of large numbers of birds during the breeding season enhances the risk of infectious diseases for the hatching chick. To test the effect of maternal yolk androgens on the chick's immune function, we experimentally manipulated, in a field study, yolk androgen levels within the physiological range by in ovo injection of either androgens (testosterone and androstenedione) or sesame oil (control) into freshly laid eggs. We determined cell-mediated immunity (CMI) and humoral immunity of the chicks at the beginning of the nestling period to evaluate early modulatory effects of yolk androgens on immune function. Embryonic exposure to elevated levels of androgens negatively affected both CMI and humoral immunity in nestling gull chicks. Consequently, maternal yolk androgens not only entail benefits of enhanced competitiveness and growth as previously shown, but also costs in terms of immunosuppression. The outcome of embryonic yolk androgen exposure thus likely depends on the post-hatching circumstances for the developing offspring such as parasite exposure and degree of sibling competition.

  13. Plastic ingestion by a generalist seabird on the coast of Uruguay.

    PubMed

    Lenzi, Javier; Burgues, María Fernanda; Carrizo, Daniel; Machín, Emanuel; Teixeira-de Mello, Franco

    2016-06-15

    We analyzed plastic ingestion by Kelp Gull (Larus dominicanus) from 806 pellets collected between 2011 and 2013. Employing a Raman spectroscopy, we characterized those polymers used to produce the plastics ingested. Debris was recorded in 143 pellets (%FO=17.7%, n=202, 92.58g). Plastic was found in 119 pellets (%FO=83%) and non-plastic occurred in 56 pellets (%FO=39%). The most important debris category was plastic film with 55.3% (n=79). Plastic bags were observed in 19 pellets (%FO=2.4%, weight=25.02g). Glass was the second most important component (%FO=18.9%) followed by plastic fragments (%FO=17.8%). Plastic debris represented the 65.3% of the debris fragments (n=132, weight=58.84g), and was composed by polyethylene (52%), polypropylene (26%), polyamide (12%), polystyrene (6%), polyvinyl chloride (2%), and polyethylene terephthalate (2%). How plastics were obtained by gulls and the effects on individuals are discussed, as well as environmental considerations about plastic pollution on coastal environments.

  14. Effects of egg oiling on larid productivity and population dynamics

    USGS Publications Warehouse

    Lewis, S.J.; Malecki, R.A.

    1984-01-01

    Small quantities of petroleum may adhere to the plumage, feet, or nest materials of breeding birds and be transferred to their eggs during incubation. In this study, oil was applied to naturally incubated Great Black-backed Gull (Larus marinus) and Herring Gull (L. argentatus) eggs, and its effects on reproductive success were assessed. Embryo survival was inversely proportional to the quantity of petroleum applied to eggshell surfaces. Dose responses, however, were dependent on embryonic age at the time of treatment. Eggs of either species, treated with 10-20 μl of No. 2 fuel oil 4-8 days after laying, experienced significant reductions in hatching success. Embryos oiled past the midpoint of the 28-day incubation period were insensitive to as much as 100 μl of petroleum. Fuel oil weathered outdoors for several weeks was as toxic as fresh oil to larid embryos. Productivity estimates obtained following various oil treatments indicated that only under severe conditions (e.g. large doses of petroleum contaminating young embryos) could egg oiling have a significant impact upon populations of the Herring Gull and species with similar life-history characteristics. Species that are more sensitive to oil, however, those having lower reproductive potentials and higher postfledging mortality rates or those subject to other stresses, may be more adversely affected by oil pollution.

  15. Differential annual movement patterns in a migratory species: effects of experience and sexual maturation.

    PubMed

    Jorge, Paulo E; Sowter, David; Marques, Paulo A M

    2011-01-01

    Some animals migrate long distances to exploit important seasonal food resources in the northern regions of the northern hemisphere, whilst avoiding winter starvation. Changes in the individual's age and navigational skills are likely to affect migration, which in turn influences the geographic distribution of individuals. Processes such as sexual maturation and navigational abilities are affected by age, and age is thus a key factor in understanding migration patterns and differences in distribution ranges. In the present study, we investigated the effects of age on the geographic distribution of a population of Lesser Black-backed Gulls Larus fuscus throughout its annual cycle, by analyzing a dataset of 19,096 records from 10,000 color-ringed gulls. In contrast to previous assumptions, the results showed that gulls were geographically segregated by age throughout the entire annual cycle, rather than showing a geographic age-related cline only in the wintering areas. This asymmetric distribution results from a reduction in the annual range of sexually mature gulls, and the differential distribution of mature and immature individuals (mature birds remained in more northern areas, compared to immature birds, throughout the annual cycle). Furthermore, although immature gulls travelled longer distances than adults, they initiated their fall migration with short movements, in contrast to adults that migrated using longer movements. The effects identified in this study explain the non-homogenous distribution of populations throughout the annual cycle, with wide implications for the development of effective human health policies and/or wildlife management strategies.

  16. Avian Influenza Virus Isolated in Wild Waterfowl in Argentina: Evidence of a potentially unique phylogenetic lineage in South America

    PubMed Central

    Pereda, Ariel J.; Uhart, Marcela; Perez, Alberto A.; Zaccagnini, Maria E.; La Sala, Luciano; Decarre, Julieta; Goijman, Andrea; Solari, Laura; Suarez, Romina; Craig, Maria I.; Vagnozzi, Ariel; Rimondi, Agustina; König, Guido; Terrera, Maria V.; Kaloghlian, Analia; Song, Haichen; Sorrell, Erin M.; Perez, Daniel R.

    2008-01-01

    Avian Influenza (AI) viruses have been sporadically isolated in South America. The most recent reports are from an outbreak in commercial poultry in Chile in 2002 and its putative ancestor from a wild bird in Bolivia in 2001. Extensive surveillance in wild birds was carried out in Argentina during 2006-2007. Using RRT-PCR, 12 AI positive detections were made from cloacal swabs. One of those positive samples yielded an AI virus isolated from a wild kelp gull (Larus dominicanus) captured in the South Atlantic coastline of Argentina. Further characterization by nucleotide sequencing reveals that it belongs to the H13N9 subtype. Phylogenetic analysis of the 8 viral genes suggests that the 6 internal genes are related to the isolates from Chile and Bolivia. The analysis also indicates that a cluster of phylogenetically related AI viruses from South America may have evolved independently, with minimal gene exchange, from influenza viruses in other latitudes. The data produced from our investigations are valuable contributions to the study of AI viruses in South America. PMID:18632129

  17. Arsenic accumulation in livers of pinnipeds, seabirds and sea turtles: subcellular distribution and interaction between arsenobetaine and glycine betaine.

    PubMed

    Fujihara, Junko; Kunito, Takashi; Kubota, Reiji; Tanabe, Shinsuke

    2003-12-01

    Concentrations of total arsenic and individual arsenic compounds were determined in liver samples of pinnipeds (northern fur seal Callorhinus ursinus and ringed seal Pusa hispida), seabirds (black-footed albatross Diomedea nigripes and black-tailed gull Larus crassirostris) and sea turtles (hawksbill turtle Eretmochelys imbricata and green turtle Chelonia mydas). Among these species, the black-footed albatross contained the highest hepatic arsenic concentration (5.8+/-3.7 microg/g wet mass). Arsenobetaine was the major arsenic species found in the liver of all these higher tropic marine animals. To investigate the cause of high accumulation of arsenobetaine, subcellular distribution of arsenic and relationship between arsenobetaine and glycine betaine concentrations were examined in the livers of these animals. There was no relationship between total arsenic concentration and its subcellular distribution in liver tissues. However, a significant negative correlation was found between arsenobetaine and glycine betaine concentrations in the liver of six species examined. This result may indicate that arsenobetaine is accumulated in these marine animals as an osmolyte along with glycine betaine, which is a predominant osmolyte in marine animals because the chemical structure and properties of arsenobetaine are similar to those of glycine betaine.

  18. Reduction of garbage in the diet of nonbreeding glaucous gulls corresponding to a change in waste management

    USGS Publications Warehouse

    Weiser, E.L.; Powell, A.N.

    2011-01-01

    Glaucous gulls (Larus hyperboreus) are major predators in the Arctic and may benefit from human development. We studied use of garbage by glaucous gulls in Barrow, Alaska, in 2007, when municipal waste was disposed of in a landfill, and in 2008, when it was incinerated. In both years, diet samples from breeding adult gulls contained less garbage than those from loafing nonbreeding gulls (mostly subadults of less than four years), possibly because the breeding colony was more distant than many loafing sites from the landfills. Although breeding gull samples showed no change, garbage in regurgitated pellets and food remains of nonbreeding gulls was significantly less prevalent in 2008 than in 2007 (28% vs. 43% occurrence in diet samples), and this reduction could be explained by the switch from landfill to waste incineration. Yet garbage remained a substantial part of nonbreeding gull diet after the management change. Other aspects of waste management, such as storage prior to disposal, may also be important in limiting scavengers' access to garbage and thus reducing the indirect impact of human development on prey species of conservation concern. ?? The Arctic Institute of North America.

  19. Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.

    PubMed

    Prestrud, Kristin Wear; Asbakk, Kjetil; Fuglei, Eva; Mørk, Torill; Stien, Audun; Ropstad, Erik; Tryland, Morten; Gabrielsen, Geir Wing; Lydersen, Christian; Kovacs, Kit M; Loonen, Maarten J J E; Sagerup, Kjetil; Oksanen, Antti

    2007-11-30

    Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion of seropositive animals was 43% in arctic foxes, 7% in barnacle geese, and 6% (1 of 17) in walruses. There were no seropositive Svalbard reindeer, sibling voles, glaucous gulls, or kittiwakes. The prevalence in the arctic fox was relatively high compared to previous reports from canid populations. There are no wild felids in Svalbard and domestic cats are prohibited, and the absence of antibodies against T. gondii among the herbivorous Svalbard reindeer and voles indicates that transmission of the parasite by oocysts is not likely to be an important mechanism in the Svalbard ecosystem. Our results suggest that migratory birds, such as the barnacle goose, may be the most important vectors bringing the parasite to Svalbard. In addition to transmission through infected prey and carrion, the age-seroprevalence profile in the fox population suggests that their infection levels are enhanced by vertical transmission.

  20. Accumulation of chlorinated benzenes in earthworms

    SciTech Connect

    Beyer, W.N.

    1996-12-31

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. They probably entered the water as leachates from chemical waste dumps and as effluents from manufacturing. Hexachlorobenzene and pentachlorobenzene are commonly present in Herring gull (Larus argentatus) eggs from the Great Lakes, and some of the isomers of trichlorobenzene and tetrachlorobenzene are occasionally detected at low concentrations. Hexachlorobenzene, which was formerly used as a fungicide, has been the most thoroughly studied chlorinated benzene, and has been detected in many species. Its use as a fungicide in the United States was canceled in 1984. Since about 1975 hexachlorobenzene has been formed mainly in the production of chlorinated solvents. It is highly persistent in the environment and some species are poisoned by hexachlorobenzene at very low chronic dietary exposures. As little as 1 ppm in the diet of mink (Mustela vison) reduced the birth weights of young, and 5 ppm in the diet of Japanese quail (Coturnix coturnix japonica) caused slight liver damage. This paper describes a long-term (26 wk) experiment relating the concentrations of chlorinated benzenes in earthworms to length of exposure and three 8 wk experiments relating concentration to the concentration in soil the soil organic matter content, and the degree of chlorination. 20 refs., 3 figs., 1 tab.

  1. Parasitic fauna of a yellow-legged gull colony in the island of Escombreras (South-eastern Mediterranean) in close proximity to a landfill site: potential effects on cohabiting species.

    PubMed

    Parejo, Sandra Hervías; Martínez-Carrasco, Carlos; Diaz, Julia I; Chitimia, Lidia; Ortiz, Juana; Mayo, Elvira; Ybáñez, Rocío Ruiz de

    2015-06-01

    We identified the ectoparasites and helminth fauna of yellow-legged gulls (Larus michahellis michahellis), breeding near to a solid waste landfill, and compared infection levels with those of other yellow-legged gull colonies. Moreover, we analysed correlations between parasites and sex and body condition of yellow-legged gulls, co-infections and the helminth community structure in order to propose the role of this species as reservoir of certain parasites. We also discuss the potential transmission of parasites between the yellow-legged gull and the endangered Audouin's gull, because interactions between these two species, such as kleptoparasitism and predation, occur frequently around colonies. The following species were recorded: Ornithodorus capensis (Arthropoda); Cosmocephalus obvelatus, Paracuaria adunca, Eucoleus contortus, Tetrameres skrjabini and Contracaecum sp. (Nematoda); Tetrabothrius cylindraceus (Cestoda); Acanthotrema armata, Cardiocephaloides longicollis and Ornithobilharzia intermedia (Digenea). Tetrabothrius cylindraceus, A. armata and O. capensis are new parasite records for this host. The dependence of yellow-legged-gulls on fishery discards is supported by the dominance of parasites transmitted through marine intermediate hosts with interest to fisheries in the study area. However, the shift in diet from natural resources to food derived from human activities seems not to affect the parasitic fauna of yellow-legged gull. Besides of direct physical contact between individuals in nesting and resting habitats, the high availability of fishery discards could increase the risk of Audouin's gulls to be infected by common parasites of yellow-legged gull.

  2. Porphyrin levels in excreta of sea birds of the Chilean coasts as nondestructive biomarker of exposure to environmental pollutants.

    PubMed

    Casini, S; Fossi, M C; Gavilan, J F; Barra, R; Parra, O; Leonzio, C; Focardi, S

    2001-07-01

    In this preliminary study on sea birds we propose the use of porphyrins in excreta as a biomarker of exposure to contaminants. Samples of excreta were obtained from colonies of brown pelicans (Pelecanus occidentalis thagus), neotropic cormorants (Phalacrocorax olivaceus), and kelp gulls (Larus dominicanus) in three areas of the south coast of Chile with different human impact (Tubul, Talcahuano, and Valdivia). They were analyzed for porphyrin content (copro-, uro-, and protoporphyrins and total porphyrins) by a rapid fluorimetric method and by HPLC. The main outcomes of the study were: (a) kelp gulls and neotropic cormorants living in areas with high human impact showed a clear capacity to accumulate and eliminate porphyrins in the excreta; (b) species-related accumulation capacities are likely, as shown by the different levels found in different species living in the same area; (c) the porphyrin profile obtained by fluorimetry and HPLC showed a higher percentage of protoporphyrin than the other porphyrins; (d) although the fluorimetric method of Grandchamp is semiquantitative, it was found to be sensitive enough to detect differences in samples from field studies. The positive results of this preliminary study make it possible to propose this nondestructive method for a variety of field applications.

  3. An epidemic of Newcastle disease in double-crested cormorants from Saskatchewan.

    PubMed

    Kuiken, T; Leighton, F A; Wobeser, G; Danesik, K L; Riva, J; Heckert, R A

    1998-07-01

    A Newcastle disease epidemic in double-crested cormorants (Phalacrocorax auritus) occurred in July and August 1995, during a 1994-96 study of a breeding colony of this species on Doré Lake (Saskatchewan, Canada). Clinical signs and mortality were observed from a tunnel-and-blind system, and moribund and freshly dead birds were examined virologically. Yolks from cormorant eggs and sera from cormorants and other birds were tested for hemagglutination inhibiting antibodies to Newcastle disease virus (NDV). Evidence of Newcastle disease was limited to juvenile double-crested cormorants, despite close contact with other birds, including American white pelicans (Pelecanus erythrorhynchos) and gulls (Larus spp.). Clinical signs included limb, head or neck paralysis, head or body tremors, ataxia, and blindness; pathogenic NDV was isolated from affected birds. The mortality rate of juvenile cormorants was 32 to 64%, which was high relative to overall first-year mortality in years without epidemics. Thirty-seven of 63 (59%) cormorant sera collected during the epidemic tested positive for antibodies to NDV. Antibody status of cormorant egg yolks depended on stage of incubation, likely due to changes in the amount of water in the yolks. The departure of juvenile cormorants from their nests at 4 wk of age, resulting in an increased contact rate among individuals, may have been important in triggering the epidemic.

  4. Bald eagle predation on common loon egg

    USGS Publications Warehouse

    DeStefano, Stephen; McCarthy, Kyle P.; Laskowski, Tom

    2010-01-01

    The Common Loon (Gavia immer) must defend against many potential egg predators during incubation, including corvids, Herring Gulls (Larus argentatus), raccoons (Procyon lotor), striped skunk (Mephitis mephitis), fisher (Martes pennanti), and mink (Neovison vison) (McIntyre 1988, Evers 2004, McCann et al. 2005). Bald Eagles (Haliaeetus leucocephalus) have been documented as predators of both adult Common Loons and their chicks (Vliestra and Paruk 1997, Paruk et al. 1999, Erlandson et al. 2007, Piper et al. 2008). In Wisconsin, where nesting Bald Eagles are abundant (>1200 nesting pairs, >1 young/pair/year), field biologists observed four instances of eagle predation of eggs in loon nests during the period 2002–2004 (M. Meyer pers. comm.). In addition, four cases of eagle predation of incubating adult loons were inferred from evidence found at the loon nest (dozens of plucked adult loon feathers, no carcass remains) and/or loon leg, neck, and skull bones beneath two active eagle nests, including leg bones containing the bands of the nearby (<25 m) incubating adult loon. However, although loon egg predation has been associated with Bald Eagles, predation events have yet to be described in peer-reviewed literature. Here we describe a photographic observation of predation on a Common Loon egg by an immature Bald Eagle as captured by a nest surveillance video camera on Lake Umbagog, a large lake (32 km2) at Umbagog National Wildlife Refuge (UNWR) in Maine.

  5. Interannual variations of the occurrence of epipelagic fish in the diets of the seabirds breeding on Teuri Island, northern Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Deguchi, Tomohiro; Watanuki, Yutaka; Niizuma, Yasuaki; Nakata, Akifumi

    2004-05-01

    The diets of breeding seabirds can be a good monitor of marine environmental changes. From 1984 to 2001 we monitored the diets of black-tailed gulls ( Larus crassirostris) (“surface foragers”), rhinoceros auklets ( Cerorhinca monocerata) (“epipelagic divers”), and Japanese cormorants ( Phalacrocorax filamentotus) (“bottom divers”) that breed on Teuri Island at the northern boundary of the Tsushima Warm current in the Sea of Japan/East Sea. Between 1984 and 1987, both the gulls and the auklets foraged on the sardine ( Sardinops melanostictus), but after 1992, they switched to the anchovy ( Engraulis japonica). This change might reflect the collapse of the sardine stock in the late 1980s. In the 1990s, the year-to-year variations of the percentage of anchovy in the diets of the three seabird species showed similar trends: High in 1994 and 1998-2001; and low in 1992-1993 and 1995-1997. The estimated stock size of the anchovy population in the Tsushima Current area was positively correlated with the percentage of mass of anchovy in the seabirds’ diets. Thus, the short-term annual changes of the total anchovy availability, which might reflect SST or the volume transport of Tsushima Current, possibly affected the seabirds diets on this island.

  6. Flap or soar? How a flight generalist responds to its aerial environment.

    PubMed

    Shamoun-Baranes, Judy; Bouten, Willem; van Loon, E Emiel; Meijer, Christiaan; Camphuysen, C J

    2016-09-26

    The aerial environment is heterogeneous in space and time and directly influences the costs of animal flight. Volant animals can reduce these costs by using different flight modes, each with their own benefits and constraints. However, the extent to which animals alter their flight modes in response to environmental conditions has rarely been studied in the wild. To provide insight into how a flight generalist can reduce the energetic cost of movement, we studied flight behaviour in relation to the aerial environmental and landscape using hundreds of hours of global positioning system and triaxial acceleration measurements of the lesser black-backed gull (Larus fuscus). Individuals differed largely in the time spent in flight, which increased linearly with the time spent in flight at sea. In general, flapping was used more frequently than more energetically efficient soaring flight. The probability of soaring increased with increasing boundary layer height and time closer to midday, reflecting improved convective conditions supportive of thermal soaring. Other forms of soaring flight were also used, including fine-scale use of orographic lift. We explore the energetic consequences of behavioural adaptations to the aerial environment and underlying landscape and implications for individual energy budgets, foraging ecology and reproductive success.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  7. Amino Acid Specific Stable Nitrogen Isotope Values in Avian Tissues: Insights from Captive American Kestrels and Wild Herring Gulls.

    PubMed

    Hebert, C E; Popp, B N; Fernie, K J; Ka'apu-Lyons, C; Rattner, B A; Wallsgrove, N

    2016-12-06

    Through laboratory and field studies, the utility of amino acid compound-specific nitrogen isotope analysis (AA-CSIA) in avian studies is investigated. Captive American kestrels (Falco sparverius) were fed an isotopically characterized diet and patterns in δ(15)N values of amino acids (AAs) were compared to those in their tissues (muscle and red blood cells) and food. Based upon nitrogen isotope discrimination between diet and kestrel tissues, AAs could mostly be categorized as source AAs (retaining baseline δ(15)N values) and trophic AAs (showing (15)N enrichment). Trophic discrimination factors based upon the source (phenylalanine, Phe) and trophic (glutamic acid, Glu) AAs were 4.1 (muscle) and 5.4 (red blood cells), lower than those reported for metazoan invertebrates. In a field study involving omnivorous herring gulls (Larus argentatus smithsonianus), egg AA isotopic patterns largely retained those observed in the laying female's tissues (muscle, red blood cells, and liver). Realistic estimates of gull trophic position were obtained using bird Glu and Phe δ(15)N values combined with β values (difference in Glu and Phe δ(15)N in primary producers) for aquatic and terrestrial food webs. Egg fatty acids were used to weight β values for proportions of aquatic and terrestrial food in gull diets. This novel approach can be applied to generalist species that feed across ecosystem boundaries.

  8. Serologic survey of potential vertebrate hosts for West Nile virus in Poland.

    PubMed

    Hubálek, Zdenek; Wegner, Elzbieta; Halouzka, Jirí; Tryjanowski, Piotr; Jerzak, Leszek; Sikutová, Silvie; Rudolf, Ivo; Kruszewicz, Andrzej G; Jaworski, Zbigniew; Wlodarczyk, Radoslaw

    2008-06-01

    A survey for antibodies to West Nile virus (WNV; genus ,Flavivirus) was carried out by plaque-re-duction neutralization microtesting in 78 horses, 20 domestic chickens, and 97 wild birds belonging to 10 species from different areas in Poland. Specific antibodies were detected in five juvenile (hatching-year) birds collected in 2006: three white storks (Ciconia ciconia) in a wildlife rehabilitation center (5.4% of all examined storks; the antibody titers in each bird were 1:320, 1:160, and 1:20), one free-living mute swan (Cygnus olor; the titer was 1:20), and one hooded crow (Corvus corone cornix; the titer 1:20) in a wildlife rehabilitation center; thus the overall seropositivity to WNV was 5.2% among all the birds sampled. These data do not rule out the presence of WNV activity in Poland with 100% certainty, but they indicate a significant trace that demands verification. In addition, one black-headed gull (Larus ridibundus) had neutralizing antibodies for the Usutu Flavivirus, the first case recorded in Poland.

  9. Begging coordination between siblings in Black-headed Gulls.

    PubMed

    Blanc, Alain; Ogier, Nicolas; Roux, Angélique; Denizeau, Sébastien; Mathevon, Nicolas

    2010-09-01

    Communication behaviours are now considered from a signallers-receivers network perspective. This concept seems well suited to the study of interactions between parents and offspring in birds, so far mainly treated as a dyadic signalling system involving the brood or a single chick as a signaller and the parent as a receiver. Family conflicts over resource allocation drive parent-offspring and sib-sib communication. In the Black-headed Gull Larus ridibundus, parents respond to the whole-brood begging intensity and siblings often synchronize their begging signalling thus limiting individual effort. By monitoring five nests of two-chick broods during the whole rearing period in the nest, we show how an intra-brood simultaneity of begging emerges from successive phases of solitary begging of junior and senior nestlings. Although this result remains preliminary due to the sample size, it underlines a dynamical aspect of chicks' behaviour. Because they always favour coordinated begging and because they elevate their response threshold across the rearing period, parents may play a major role in the plasticity of begging behaviour.

  10. The effect of maternal state on the steroid and macronutrient content of lesser black-backed gull eggs.

    PubMed

    Verboven, Nanette; Monaghan, Pat; Nager, Ruedi G; Evans, Neil P

    2010-01-01

    It has been proposed that female birds can influence the phenotype of their offspring by provisioning eggs with variable amounts of nutrients and maternal hormones. Egg quality is strongly influenced by maternal body reserves and the amount of food available at the time of egg formation. This study investigated the effects of maternal state and food availability on the capacity of female lesser black-backed gulls Larus fuscus to provision their eggs with macronutrients and steroid hormones. Maternal state was reduced by increasing egg-production effort, whereas extra food was provided to reverse this effect. Compared with eggs of first clutches, eggs of experimentally induced replacement clutches exhibited a lower yolk/albumen ratio and contained more yolk testosterone. During one of the three years in which the study was performed, replacement eggs also contained more 17β-estradiol. Food provisioning during the relaying interval did not affect changes in yolk/albumen ratio or steroid concentrations, but fed females produced bigger eggs in their replacement clutch. This study demonstrates significant within-female consistency in egg size, macronutrient content, and yolk steroid concentration, and it shows that these egg characteristics are influenced by maternal state, food availability, and the timing of breeding.

  11. Experience modulates both aromatase activity and the sensitivity of agonistic behaviour to testosterone in black-headed gulls.

    PubMed

    Ros, Albert F H; Franco, Aldina M A; Groothuis, Ton G G

    2009-04-20

    In young black-headed gulls (Larus ridibundus), exposure to testosterone increases the sensitivity of agonistic behaviour to a subsequent exposure to this hormone. The aim of this paper is twofold: to analyze whether social experience, gained during testosterone exposure, mediates this increase in hormonal sensitivity (priming), and whether this in turn is mediated by an increase in central aromatase activity. To this end, we performed three experiments. In the first juvenile gulls were exposed to two consecutive treatments with testosterone (T1 and T2), with more than a week interval in between. During T1, half of the birds were housed in social isolation (Iso) and the other half in groups (Soc). All birds were re-housed in a new social situation during the second treatment. The increase in social behaviour during T2 was significantly more rapid in Soc than Iso birds. In experiment 2 we show that 17beta-estradiol treatment facilitates the behaviour measured in experiment 1. In experiment 3 we used a set-up comparable with that of experiment 1, but birds were sacrificed early in the T2 period. Aromatase activity in the preoptic area and the hypothalamus was measured using the tritiated water releasing method. In some parts of the preoptic area and hypothalamus aromatase activity was higher in Soc birds relative to Iso birds. The results indicate that social experience can modulate the increase of social behaviour to testosterone via modulation of aromatase activity and independently of actual hormone levels.

  12. Experimental infection and pathology of clade 2.2 H5N1 virus in gulls

    PubMed Central

    Gulyaeva, Marina A.; Zaykovskaia, Anna V.; Shestopalova, Lidia V.; Shestopalov, Aleksander M.

    2016-01-01

    During 2006, H5N1 HPAI caused an epizootic in wild birds, resulting in a die-off of Laridae in the Novosibirsk region at Chany Lake. In the present study, we infected common gulls (Larus canus) with a high dose of the H5N1 HPAI virus isolated from a common gull to determine if severe disease could be induced over the 28 day experimental period. Moderate clinical signs including diarrhea, conjunctivitis, respiratory distress and neurological signs were observed in virus-inoculated birds, and 50% died. The most common microscopic lesions observed were necrosis of the pancreas, mild encephalitis, mild myocarditis, liver parenchymal hemorrhages, lymphocytic hepatitis, parabronchi lumen hemorrhages and interstitial pneumonia. High viral titers were shed from the oropharyngeal route and virus was still detected in one bird at 25 days after infection. In the cloaca, the virus was detected sporadically in lower titers. The virus was transmitted to direct contact gulls. Thus, infected gulls can pose a significant risk of H5N1 HPAIV transmission to other wild migratory waterfowl and pose a risk to more susceptible poultry species. These findings have important implications regarding the mode of transmission and potential risks of H5N1 HPAI spread by gulls. PMID:26243601

  13. Lead and cadmium accumulation in eggs and fledgling seabirds in the New York Bight

    SciTech Connect

    Burger, J. ); Gochfeld, M. )

    1993-02-01

    The authors measured lead and cadmium concentrations in eggs and in the breast feathers of fledglings of common tern (Sterna hirundo), roseate tern (S. dougallii), Forster's tern (S. forsteri), black skimmer (Rynchops niger), and herring gull (Larus argentatus) nesting in mixed-species colonies in the New York Bight in 1989. Metal concentrations in fledgling feathers represent in part metals sequestered in the egg by females and accumulation from food brought back to chicks by parents, and thus may be a measure of local metal acquisition. There were significant interspecific differences in lead in eggs, and lead and cadmium in fledgling feathers. Herring gulls had the most lead in eggs, whereas the terns had the least. Cadmium concentrations were generally low in all examined eggs. Lead concentrations were high in fledgling feathers in some populations of all species. Cadmium was highest in fledgling terns, the roseate tern had the highest concentrations. For all species except herring gull, the feathers of fledglings had higher levels of metals than did eggs.

  14. Immune status, carotenoid coloration, and wing feather growth in relation to organochlorine pollutants in great black-backed gulls.

    PubMed

    Bustnes, Jan Ove; Kristiansen, Kai Ove; Helberg, Morten

    2007-07-01

    Previous ecotoxicological studies have documented relationships between residues of various organochlorines (OCs) and immune status, carotenoid colors, and wing feather growth in different bird species. In this study, the density of white blood cells (WBC), carotenoid colors, and length of the same feathers on each wing were measured in breeding great black-backed gulls (Larus marinus) on the coast of northern Norway, and related to the blood residues of five OCs, including HCB (hexachlorobenzene), beta-HCH (beta-hexachlorocyclohexane), p,p'-DDE (p, p'-dichlorodiphenyldichloroethylene), oxychlordane, and polychlorinated biphenyl (PCB), in addition to SigmaOC. Neither, WBC density nor carotenoid colors were significantly related to blood residues of any of the OCs, suggesting that OC levels may have been too low to significantly affect these outcome parameters. However, in the colony where the OC concentrations were highest, there was a weak but significantly positive relationship between the probability of having different length of feathers on each wing and levels of PCB and SigmaOC, in males. Thus varying length of the wing primaries may reflect adverse impacts of OCs in great black-backed gulls. However, in gulls with moderate levels of OCs, it is probably not a sensitive indicator of progressing ecological impacts of OCs, since such adverse ecological relationships were found in the breeding colonies where there were no relationships between differences in wing feather lengths and OCs.

  15. Susceptibility of North American Ducks and Gulls to H5N1 Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    Stallknecht, David E.; Beck, Joan R.; Suarez, David L.; Swayne, David E.

    2006-01-01

    Since 2002, H5N1 highly pathogenic avian influenza (HPAI) viruses have been associated with deaths in numerous wild avian species throughout Eurasia. We assessed the clinical response and extent and duration of viral shedding in 5 species of North American ducks and laughing gulls (Larus atricilla) after intranasal challenge with 2 Asian H5N1 HPAI viruses. Birds were challenged at ≈10 to 16 weeks of age, consistent with temporal peaks in virus prevalence and fall migration. All species were infected, but only wood ducks (Aix sponsa) and laughing gulls exhibited illness or died. Viral titers were higher in oropharyngeal swabs than in cloacal swabs. Duration of viral shedding (1–10 days) increased with severity of clinical disease. Both the hemagglutination-inhibition (HI) and agar gel precipitin (AGP) tests were able to detect postinoculation antibodies in surviving wood ducks and laughing gulls; the HI test was more sensitive than the AGP in the remaining 4 species PMID:17283615

  16. Human-Induced Long-Term Shifts in Gull Diet from Marine to Terrestrial Sources in North America's Coastal Pacific: More Evidence from More Isotopes (δ2H, δ34S).

    PubMed

    Hobson, Keith A; Blight, Louise K; Arcese, Peter

    2015-09-15

    Measurements of naturally occurring stable isotopes in tissues of seabirds and their prey are a powerful tool for investigating long-term changes in marine foodwebs. Recent isotopic (δ(15)N, δ(13)C) evidence from feathers of Glaucous-winged Gulls (Larus glaucescens) has shown that over the last 150 years, this species shifted from a midtrophic marine diet to one including lower trophic marine prey and/or more terrestrial or freshwater foods. However, long-term isotopic patterns of δ(15)N and δ(13)C cannot distinguish between the relative importance of lower trophic-level marine foods and terrestrial sources. We examined 48 feather stable-hydrogen (δ(2)H) and -sulfur (δ(34)S) isotope values from this same 150-year feather set and found additional isotopic evidence supporting the hypothesis that gulls shifted to terrestrial and/or freshwater prey. Mean feather δ(2)H and δ(34)S values (± SD) declined from the earliest period (1860-1915; n = 12) from -2.5 ± 21.4 ‰ and 18.9 ± 2.7 ‰, respectively, to -35.5 ± 15.5 ‰ and 14.8 ± 2.4 ‰, respectively, for the period 1980-2009 (n = 12). We estimated a shift of ∼ 30% increase in dependence on terrestrial/freshwater sources. These results are consistent with the hypothesis that gulls increased terrestrial food inputs in response to declining forage fish availability.

  17. Winter marine bird and sea otter abundance of Prince William Sound, Alaska: Trends following the t/v Exxon Valdez oil spill from 1990-94. Restoration project 94159. Exxon Valdez oil spill restoration project final report

    SciTech Connect

    Agler, B.A.; Seiser, P.E.; Kendall, S.J.; Irons, D.B.

    1995-05-01

    We conducted small boat surveys to determine population abundance of marine birds and sea otters (Enhydra lutris) in Prince William Sound, Alaska during March 1994. We observed 45 bird and 8 mammal species in Prince William Sound, and we estimated that 320,470 + or - 63,640 marine birds were present. We estimated trends in the March population estimates from 1990-94 by determining whether estimates in the oiled zone changed at the same rate as those in the unoiled zone. For Prince William Sound as a whole, we also examined the population trends from 1990-94 using regression analyses. We found significant positive trends for harlequin duck (Histrionicus), goldeneye, merganser, bald eagle (Haliaeetus leucocephalus), black-legged kittiwake (Rissa tridactyla) and gull (Larus and Rissa spp.) populations. We also examined the relative abundance of marine bird species groups from 1972 to 1994. During March 1994, we estimated that the sea otter population was 7,746 + or - 2,073 otters. We found no difference in the rate of change between the oiled and unoiled zones from 1990-94, and there was no significant trend in the total number of sea otters in Prince William Sound from 1990-94.

  18. Shell thinning and pesticide residues in Texas aquatic bird eggs, 1970

    USGS Publications Warehouse

    King, K.A.; Flickinger, Edward L.; Hildebrand, H.H.

    1978-01-01

    Significant decreases in eggshell thickness were found in 15 of 22 species of aquatic birds in Texas in 1970. Shell thickness reductions of 9 to 15 percent were found in white pelicans (Pelecanus erythrorhynchos), brown pelicans (P .occidentalis), and great blue herons (Ardea herodias). DDT family compounds were found in all eggs, and mean residues ranged from 0.4 ppm in white ibis (Eudocimus albus) to 23.2 ppm in great egrets (Casmerodius albus). GDDT residues were negatively correlated with shell thickness in five species; PCBs were negatively correlated in two. Residues in marine birds were generally lower and more uniform than levels in birds feeding in fresh and brackish water. DDT and dieldrin residues were higher in eggs from colonies near agricultural areas where these insecticides were heavily used; higher PCB residues were consistently associated with urban and industrial areas. Populations of five species have declined and deserve continued study: brown pelican, reddish egret (Dichromanassa rufescens), white-faced ibis (Plegadis chihi), laughing gull (Larus atricilla), and Forster's tern (Sterna forsteri). Population trends of four other species were undetermined and should be followed closely in future years.

  19. Polybrominated diphenyl ethers, toxaphenes, and other halogenated organic pollutants in great blue heron eggs.

    PubMed

    Champoux, Louise; Moisey, John; Muir, Derek C G

    2010-02-01

    The great blue heron (Ardea herodias) has been used as a bioindicator of the state of the St. Lawrence River (Québec, Canada) since 1996. At 5-year intervals, selected breeding colonies along the River and its estuary are visited to estimate reproductive success and determine levels of contamination. Brominated flame retardants are found in many ecosystems and are increasing in concentration in the Great Lakes, which is the source of much of the water for the St. Lawrence River. In 2001 and 2002, in addition to polychlorinated biphenyls (PCBs) and chlorinated pesticides, the levels of polybrominated diphenyl ethers (PBDEs), polychlorinated bornanes (toxaphene) congeners and non-ortho-substituted PCBs were measured for the first time in pools of great blue heron eggs. The PBDE levels in great blue heron eggs (70-1,377 ng/g wet wt) were comparable to those measured in herring gull (Larus argentatus) eggs from the Great Lakes. Toxaphene was detected in great blue heron eggs at levels comparable to those of other major chlorinated pesticides. Major toxaphene congeners were octachlorobornane P44 and the nonachlorobornane P50. Environ.

  20. Waterbird predation on fish in western Lake Erie: a bioenergetics model application

    USGS Publications Warehouse

    Madenjian, Charles P.; Gabrey, Steven W.

    1995-01-01

    To better understand the role of piscivorous waterbirds in the food web of western Lake Erie, we applied a bioenergetics model to determine their total fish consumption, The important nesting species included the Herring Gull (Larus argentatus), Ring-billed Gull (L. delawarensis), Double-crested Cormorant (Phalacrocorax auritus), Great Blue Heron (Ardea herodias), Black-crowned Night-Heron (Nycticorax nycticorax), and Great Egret (Casmerodius albus). The impact of migrant waterbirds, including the Red-breasted Merganser (Mergus serrator), on western Lake Erie fish biomass was also considered in the analysis. According to the modeling results, during the early 1990s, piscivorous waterbirds consumed 13,368 tonnes of fish from western Lake Erie each year. This tonnage was equivalent to 15.2% of the prey fish biomass needed to support the walleye (Stizostedion vitreum) population in western Lake Erie during a single growing season. The model application was useful in quantifying energy flow between birds and fish in a large lake ecosystem.

  1. 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.

  2. Structure of marine predator and prey communities along environmental gradients in a glaciated fjord

    USGS Publications Warehouse

    Renner, Martin; Arimitsu, Mayumi L.; Piatt, John F.

    2012-01-01

    Spatial patterns of marine predator communities are influenced to varying degrees by prey distribution and environmental gradients. We examined physical and biological attributes of an estuarine fjord with strong glacier influence to determine the factors that most influence the structure of predator and prey communities. Our results suggest that some species, such as walleye pollock (Theragra chalcogramma), black-legged kittiwake (Rissa tridactyla), and glaucous-winged gull (Larus glaucescens), were widely distributed across environmental gradients, indicating less specialization, whereas species such as capelin (Mallotus villosus), harbor seal (Phoca vitulina), and Kittlitz's murrelet (Brachyramphus brevirostris) appeared to have more specialized habitat requirements related to glacial influence. We found that upper trophic level communities were well correlated with their mid trophic level prey community, but strong physical gradients in photic depth, temperature, and nutrients played an important role in community structure as well. Mid-trophic level forage fish communities were correlated with the physical gradients more closely than upper trophic levels were, and they showed strong affinity to tidewater glaciers. Silica was closely correlated with the distribution of fish communities, the mechanisms of which deserve further study.

  3. Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos.

    PubMed Central

    Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A

    1999-01-01

    Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10064546

  4. Bergmann's rule and climate change revisited: disentangling environmental and genetic responses in a wild bird population.

    PubMed

    Teplitsky, Céline; Mills, James A; Alho, Jussi S; Yarrall, John W; Merilä, Juha

    2008-09-09

    Ecological responses to on-going climate change are numerous, diverse, and taxonomically widespread. However, with one exception, the relative roles of phenotypic plasticity and microevolution as mechanisms in explaining these responses are largely unknown. Several recent studies have uncovered evidence for temporal declines in mean body sizes of birds and mammals, and these responses have been interpreted as evidence for microevolution in the context of Bergmann's rule-an ecogeographic rule predicting an inverse correlation between temperature and mean body size in endothermic animals. We used a dataset of individually marked red-billed gulls (Larus novaehollandiae scopulinus) from New Zealand to document phenotypic and genetic changes in mean body mass over a 47-year (1958-2004) period. We found that, whereas the mean body mass had decreased over time as ambient temperatures increased, analyses of breeding values estimated with an "animal model" approach showed no evidence for any genetic change. These results indicate that the frequently observed climate-change-related responses in mean body size of animal populations might be due to phenotypic plasticity, rather than to genetic microevolutionary responses.

  5. Seabirds and chronic oil pollution: self-cleaning properties of gulls, Laridae, as revealed from colour-ring sightings.

    PubMed

    Camphuysen, Kees C J

    2011-03-01

    Mystery oil spills off the Dutch coast affected colonial, adult Lesser Black-backed Gulls prior to and within the breeding season. From colour-ringed individuals, it was demonstrated that most oiled birds survived and were clean within a few weeks and often bred successfully. Further evidence of self-cleaning properties of Larus-gulls is provided from a long-term colour-ringing project (1984-2009). In total 46 birds were reported 'oiled', two died, but the majority cleaned itself and survived for up to 20 years after being oiled. From colour-ring data and 30 years of beached bird surveys (1980-2010) it is demonstrated that the effects of chronic oil pollution is larger in winter than in summer; a reflection of seasonal differences in exposure and environmental conditions. The self-cleaning properties of gulls are such that long-term survival is not necessarily jeopardized and even in a breeding season, not all is lost in case of a spill. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Assessment of blue mussel Mytilus edulis fisheries and waterbird shellfish-predator management in the Danish Wadden Sea.

    PubMed

    Laursen, Karsten; Kristensen, Per Sand; Clausen, Preben

    2010-11-01

    We assessed the blue mussel Mytilus edulis fishery management scheme introduced in 1994 in the Danish Wadden Sea that regulate fishing vessels, fishery quota, set-aside for mussel-eating birds and established zones closed to mussel fishery. The results showed (i) a reduction in the blue mussel biomass and mussel bed areas in zones closed to fishery, (ii) decrease in eiders Somateria mollissima numbers and increase or stable numbers for oystercatcher Haematopus ostralegus and herring gull Larus argentatus and (iii) that energy estimations based on ecological food requirements for the mussel-eating birds should be at least three times larger, than the amount set-aside in the mussel management scheme. It is concluded that the mussel management scheme had been unable to stabilize or increase the blue mussel stocks and to secure stable or increasing numbers for all target bird species. Thus, it is recommended to revise the present blue mussel management scheme in the Danish Wadden Sea, to continue and improve mussel stock and bird surveys, and to consider novel studies of the mussel-eating birds' energetics for improved set-aside estimates and future assessments.

  7. Living in a ghetto within a local population: an empirical example of an ideal despotic distribution.

    PubMed

    Oro, Daniel

    2008-03-01

    Merging patterns and processes about the way individuals should be distributed in a habitat is a key issue in the framework of spatial ecology. Here the despotic distribution of individuals in two distinct and neighboring patches within a local population of a long-lived colonial bird, the Yellow-legged Gull (Larus michahellis), was assessed. There was no density dependence for suitable habitat at the study population, but behavioral data suggested that birds from the good patch precluded birds from the bad patch from breeding in their patch. Younger breeders were almost exclusively found in the bad patch, where individuals were probably attracted by conspecific attraction from the good patch. Most breeding parameters were lower in the bad patch, resulting mainly from a higher vulnerability to environmental perturbations and a higher rate of intraspecific nest predation. Attempts at breeding dispersal between the two patches were only observed from the bad to the good patch. Strikingly, adult survival and large-scale dispersal, two life history parameters that are very conservative in long-lived organisms, were also more affected at the bad patch when catastrophic predation occurred. The study was consistent with an ideal despotic distribution at small spatial scale, and suggests that individual behavior can influence local population dynamics.

  8. Ecosystem respiration, vegetation development and soil nitrogen in relation to breeding density of seagulls on a pristine volcanic island, Surtsey, Iceland

    NASA Astrophysics Data System (ADS)

    Sigurdsson, B. D.; Magnusson, B.

    2009-08-01

    Since its birth in 1963 by volcanic eruption in the North Atlantic Ocean off Iceland, Surtsey has been a unique natural laboratory on how organisms colonize volcanic islands and form ecosystems with contrasting structure and function. In July, 2004, ecosystem respiration rate, soil properties and surface cover of vascular plants were measured on 21 plots distributed among the main plant communities found 40 years after the primary succession started. The plots could be divided into two groups, inside and outside seagull (Larus sp.) colonies found on the island. Vegetation cover of the plots was strongly related to the density of seagull nests within and around them. The occurrence of seagull nests and increased vegetation also coincided with significant increase in ecosystem respiration, soil carbon and nitrogen, and with significantly lower soil pH and soil temperatures. The ecosystem respiration was high inside the gull colonies, similar to the highest fluxes measured in drained wetlands or agricultural fields in Iceland. The most important factor for vegetation succession and ecosystem function on Surtsey seems to be the amount of nitrogen, which was mainly brought in by the seagulls.

  9. Effects of seagulls on ecosystem respiration, soil nitrogen and vegetation cover on a pristine volcanic island, Surtsey, Iceland

    NASA Astrophysics Data System (ADS)

    Sigurdsson, B. D.; Magnusson, B.

    2010-03-01

    When Surtsey rose from the North Atlantic Ocean south of Iceland in 1963, it became a unique natural laboratory on how organisms colonize volcanic islands and form ecosystems with contrasting structures and functions. In July, 2004, ecosystem respiration rate (Re), soil properties and surface cover of vascular plants were measured in 21 permanent research plots distributed among the juvenile communities of the island. The plots were divided into two main groups, inside and outside a seagull (Larus spp.) colony established on the island. Vegetation cover of the plots was strongly related to the density of gull nests. Occurrence of nests and increased vegetation cover also coincided with significant increases in Re, soil carbon, nitrogen and C:N ratio, and with significant reductions in soil pH and soil temperatures. Temperature sensitivity (Q10 value) of Re was determined as 5.3. When compared at constant temperature the Re was found to be 59 times higher within the seagull colony, similar to the highest fluxes measured in drained wetlands or agricultural fields in Iceland. The amount of soil nitrogen, mainly brought onto the island by the seagulls, was the critical factor that most influenced ecosystem fluxes and vegetation development on Surtsey. The present study shows how ecosystem activity can be enhanced by colonization of animals that transfer resources from a nearby ecosystem.

  10. Stable isotope analysis of avian eggs: Determining diet, feeding source and role of endogenous reserves

    SciTech Connect

    Hobson, K.A.

    1995-12-31

    Contemporary and archived avian eggs have been used extensively as a means of assessing and monitoring contaminants in the environment. Eggs can also be analyzed for stable-isotope ratios to provide dietary information that may be used to link diet of laying females with contaminant levels in eggs. Various egg components can provide integrated dietary information based on periods ranging from about a day (e.g. albumen, shell carbonate) to a week (egg yolk). In addition, some species may mobilize stored proteins and lipids from endogenous reserves during egg formation and this needs to be considered when correlating contaminant levels in eggs with dietary patterns in adult females. The role of endogenous reserves in egg formation may be assessed if individuals move between food webs with distinct isotopic profiles. This approach is illustrated using isotopic investigations of captive quail, falcons and waterfowl raised on controlled diets and of wild birds (Phalacrocorax auritus, Larus argentatus, Stema caspia, Chen caerulescens) that migrate between marine and terrestrial biomes using a variety of isotopes ({sup 13}C, {sup 15}N, {sup 34}S and D) . Whereas {sup 15}N measurements may provide information primarily of trophic level, {sup 13}C, {sup 34}S and D measurements reveal important information on source of feeding and origin of endogenous reserves.

  11. Little Egret (Egretta garzetta) as a bioindicator of trace element pollution in Tunisian aquatic ecosystems.

    PubMed

    Abdennadher, Aida; Ramírez, Francisco; Romdhane, Mohamed Salah; Ruiz, Xavier; Jover, Lluis; Sanpera, Carolina

    2011-04-01

    The Little Egret, Egretta garzetta, has breeding colonies in the island of Chikly (in the lake of Tunis) and in Thyna saltpans (in the gulf of Gabès), two important Tunisian wetlands that are strongly affected by anthropogenic activity. Here, we used E. garzetta chick feathers for environmental monitoring of breeding grounds of this species. Since trophic ecology is fundamental when interpreting contamination levels, our approach combined both trace-element (Hg, Pb, Cd, and Se) and stable-isotope analysis of δ13C, δ15N, and δ34S. Hg, Se, and δ15N levels were higher in specimens collected on Chikly than in Thyna. These observations highlight the degree of eutrophication of the lake of Tunis. Yellow-legged gulls (Larus michahellis) breeding in the same areas also feeds in the lake and attains similar concentrations of Hg and Se. In Thyna, egrets and gulls exploit distinct foraging habitats, as demonstrated by stable isotope analysis. The highest Hg and Se concentrations were found in Thyna. This result is consistent with greater exploitation of marine resources from the gulf of Gabès.

  12. Reproductive Dynamics of Sterna hirundinacea Lesson, 1831 in Ilha dos Cardos, Santa Catarina, Brazil

    PubMed Central

    Fracasso, Hélio Augusto Alves; Branco, Joaquim Olinto; Efe, Márcio Amorim

    2014-01-01

    In this work, we intend to describe the reproductive dynamics of Sterna hirundinacea in an island from South Brazil. We studied the reproductive biology of this species in its natural environment and provide data on their growth, survival, and reproductive success in Ilha dos Cardos, Santa Catarina, South Brazil. Samplings were carried out daily on the island throughout the reproductive seasons of 2003, 2005, and 2006 and the different stages of development of the chicks were characterized according to age, length of the beak, and plumage characteristics. We provide a basic equation Lm = 167.91 (1 − e −0.062t−(−0.23)) to determine the approximate age of individuals using their body mass. The main cause of chick mortality on the island was natural (63.17% in 2003, 81.41% in 2005, and 79.96% in 2006), whereas predation contributed to mortality in a proportion of 38.83% in 2003, 18.59% in 2005, and 20.04% in 2006. The absence in the area of the chicks' main predator, Kelp gull (Larus dominicanus), the large number of chicks that reached the final stages of development, and their reproductive success demonstrate that Ilha dos Cardos is an important breeding site for the species in southern Brazil. PMID:24977100

  13. Effects of gull predation and weather on survival of emperor goose goslings

    USGS Publications Warehouse

    Schmutz, Joel A.; Manly, Bryan F.J.; Dau, Christian P.

    2001-01-01

    Numbers of emperor geese (Chen canagica) have remained depressed since the mid-1980s. Despite increases in glaucous gulls (Larus hyperboreus), a primary predator of goslings, little information existed to assess whether recent patterns of gosling survival have been a major factor affecting population dynamics. We used observations of known families of emperor geese to estimate rates of gosling survival during 1993-96 on the Yukon-Kuskokwim Delta, Alaska. Survival of goslings to 30 days of age varied among years from 0.332 during 1994 to 0.708 during 1995. Survival was lowest during 1993-94, which corresponded with the years of highest frequency of disturbance of goose broods by glaucous gulls. Rainfall during early brood rearing was much higher in 1994 than other years, and this corresponded to low survival among goslings ≤5 days of age. Numbers of juveniles in families during fall staging were negatively related to rainfall during early brood rearing (n = 23 yr). Although there are no data to assess whether gosling survival in emperor geese has declined from some previous level, current survival rates of emperor goose goslings are as high as or higher than those observed in other goose species that are rapidly increasing. A proposed reduction of glaucous gull numbers by managers may not be the most effective means for increasing population growth in emperor geese.

  14. Nesting biology of Lesser Canada Geese, Branta canadensis parvipes, along the Tanana River, Alaska

    USGS Publications Warehouse

    Ely, C.R.; Pearce, J.M.; Ruess, Roger W.

    2008-01-01

    Lesser Canada Geese (Branta canadensis parvipes) are widespread throughout interior regions of Alaska and Canada, yet there have been no published studies documenting basic aspects of their nesting biology. We conducted a study to determine reproductive parameters of Lesser Canada Geese nesting along the Tanana River near the city of Fairbanks, in interior Alaska. Fieldwork was conducted in May of 2003, and consisted of locating nests along the riparian corridor between Fairbanks and Northpole, Alaska. Nests were found on gravel islands and shore habitats along the Tanana River, and were most commonly observed among driftwood logs associated with patches of alder (Alnus spp.) and willow (Salix spp.). Peak of nest initiation was 3-8 May, with a range from 27 April to 20 May; renesting was likely. Clutches ranged in size from 2 to 7 eggs and averaged 4.6 eggs. There was a negative correlation between clutch size and date of nest initiation. Egg size (mean mass = 128 g) was similar to other medium-sized Canada Geese. A positive correlation between egg size and clutch size was likely related to female age. Nineteen of 28 nests (68%) were active when visited; nests located on islands with nesting Mew Gulls (Larus canus) were more likely to be active than nests located elsewhere. Evidence at nest sites implicated Bald Eagles (Haliaeetus leucocephalus) and Red Foxes (Vulpes vulpes) as nest predators.

  15. Monitoring polycyclic aromatic hydrocarbon pollution in the marine environment after the Prestige oil spill by means of seabird blood analysis.

    PubMed

    Pérez, Cristóbal; Velando, Alberto; Munilla, Ignacio; López-Alonso, Marta; Oro, Daniel

    2008-02-01

    In this study we tested the use of seabird blood as a bioindicator of polycyclic aromatic hydrocarbon (PAH) pollution in the marine environment. Blood cells of breeding yellow-legged gulls (Larus michahellis) were able to track spatial and temporal changes consistent with the massive oil pollution pulse that resulted from the Prestige oil spill. Thus, in 2004, blood samples from yellow-legged gulls breeding in colonies that were in the trajectory of the spill doubled in theirtotal PAH concentrations when compared to samples from unoiled colonies. Furthermore, PAH levels in gulls from an oiled colony decreased by nearly a third in two consecutive breeding seasons (2004 and 2005). Experimental evidence was gathered by means of an oil-ingestion field experiment. The total concentration of PAHs in the blood of gulls given oil supplements was 30% higher compared to controls. This strongly suggested that measures of PAHs in the blood of gulls are sensitive to the ingestion of small quantities of oil. Our study provides evidence that seabirds were exposed to residual Prestige oil 17 months after the spill commenced and gives support to the nondestructive use of seabirds as biomonitors of oil pollution in marine environments.

  16. Toxicological investigations of pollutant-related effects in Great Lakes gulls

    SciTech Connect

    Peakall, D.B.; Fox, G.A.

    1987-04-01

    Reproductive failure of a number of fish-eating birds was observed on the Great Lakes in the mid-1960s to mid-1970s. The herring gull (Larus argentatus) has been used as the primary monitoring species. The low hatching success observed in this species on Lake Ontario in the mid-1970s was due to loss of eggs and failure of eggs to hatch. Egg exchange experiments demonstrated that this was due both to the incubation behavior of adults and to direct embryotoxic effects. Decrease of nest attentiveness was demonstrated using telemetered eggs, but attempts to reproduce the embryonic effects by injection of pollutant mixtures into eggs were not successful. Reproductive success improved rapidly during the late 1970s and was normal by the end of the decade. Recent studies have focused on cytogenetic and biochemical changes and detailed analytic chemistry of residues. No changes in the rate of sister chromatid exchange over values determined in coastal colonies were observed. Elevation of hepatic aryl hydrocarbon hydroxylase activity, levels of highly carboxylated porphyrins, and changes of thyroid function have been found. The geographic pattern of these changes indicates that they are caused by xenobiotics, but it has been possible to relate the changes to a specific chemical.

  17. Interspecific differences in concentrations and congener profiles of chlorinated and brominated organic pollutants in three insectivorous bird species.

    PubMed

    Dauwe, Tom; Van den Steen, Evi; Jaspers, Veerle L B; Maes, Koen; Covaci, Adrian; Eens, Marcel

    2009-02-01

    We investigated the accumulation of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) in eggs of three insectivorous bird species, the great tit (Parus major), the Northern lapwing (Vanellus vanellus) and the Mediterranean gull (Larus melanocephalus), near the harbour of Antwerp (Belgium). Our results show that lapwing eggs had the highest median concentrations of PCBs (4358 ng/g lw) and PBDEs (109 ng/g lw). Mediterranean gulls feed during breeding on ground-dwelling invertebrates on agricultural fields, which is reflected in higher OCP concentrations in eggs (1235 ng/g lw). Apart from differences in accumulation, also interspecific differences in contaminant profiles were investigated. Significant differences among species were found in the profile of PCBs, PBDEs and OCPs. These differences could be attributed to differences in diet, behaviour and metabolic capacity. Interestingly, the OCP profile in lapwing eggs deviated extremely from the two other species. In both great tit and Mediterranean gull eggs p,p'-DDE was by far the most important compound, whereas in lapwing eggs hexachlorobenzene, oxychlordane, trans-nonachlor and even p,p'-DDT were relatively more abundant than p,p'-DDE. The high p,p'-DDT/p,p'-DDE ratio has previously been described in lapwings, which suggests that low p,p'-DDE accumulation in eggs might be inherent for this species.

  18. Maternally derived testosterone and 17beta-estradiol in the eggs of Arctic-breeding glaucous gulls in relation to persistent organic pollutants.

    PubMed

    Verboven, Nanette; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Evans, Neil P

    2008-08-01

    It is largely unknown if and how persistent organic pollutants (POPs) affect the transfer of maternal hormones to eggs. This occurs despite an increasing number of studies relating environmental conditions experienced by female birds at the time of egg formation to maternal hormonal effects. Here we report the concentrations of maternal testosterone, 17beta-estradiol and major classes of POPs (organochlorines, brominated flame retardants and metabolically-derived products) in the yolk of unincubated, third-laid eggs of the glaucous gull (Larus hyperboreus), a top-predator in the Arctic marine environment. Controlled for seasonal and local variation, positive correlations were found between the concentrations of certain POPs and testosterone. Contaminant-related changes in the relative concentrations of testosterone and 17beta-estradiol were also observed. In addition, yolk steroid concentrations were associated with contaminant profiles describing the proportions of different POPs present in the yolk. Eggs from nests in which two sibling eggs hatched or failed to hatch differed in POP profiles and in the relative concentrations of testosterone and 17beta-estradiol. Although the results of this correlative study need to be interpreted with caution, they suggest that contaminant-related changes in yolk steroids may occur, possibly affecting offspring performance over and above toxic effects brought about by POPs in eggs.

  19. The phylogeny and life cycle of two species of Profilicollis (Acanthocephala: Polymorphidae) in marine hosts off the Pacific coast of Chile.

    PubMed

    Rodríguez, S M; D'Elía, G; Valdivia, N

    2017-09-01

    Resolving complex life cycles of parasites is a major goal of parasitological research. The aim of this study was to analyse the life cycle of two species of the genus Profilicollis, the taxonomy of which is still unstable and life cycles unclear. We extracted individuals of Profilicollis from two species of crustaceans (intermediate hosts) and four species of seagulls (definitive hosts) from sandy-shore and estuarine habitats along the south-east Pacific coast of Chile. Mitochondrial DNA analyses showed that two species of Profilicollis infected intermediate hosts from segregated habitats: while P. altmani larvae infected exclusively molecrabs of the genus Emerita from fully marine habitats, P. antarcticus larvae infected the crab Hemigrapsus crenulatus from estuarine habitats. Moreover, P. altmani completed its life cycle in four seagulls, Chroicocephalus maculipennis, Leucopheus pipixcan, Larus modestus and L. dominicanus, while P. antarcticus, on the other hand, completed its life cycle in the kelp gull L. dominicanus. Accordingly, our results show that two congeneric parasites use different and spatially segregated species as intermediate hosts, and both are capable of infecting one species of definitive hosts. As such, our analyses allow us to shed light on a complex interaction network.

  20. Mercury levels in Great Lakes herring gull eggs, 1972--1992

    SciTech Connect

    Weseloh, D.V.; Koster, M.D.; Ryckman, D.P.; Struger, J.

    1995-12-31

    Since 1971, the herring gull (Larus argentatus) has been used as a sentinel species for monitoring the levels of persistent contaminants in the Great Lakes ecosystem. In this study, 21 herring gull colonies in the Great Lakes and connecting channels were sampled for years 1972--1976, 1981--1983, 1985 and 1992. For each year, 10 eggs (usually) were collected from each colony site and analyzed for total mercury (ppm, wet weight). Results indicated that eggs from Lake Ontario displayed the highest mercury levels, mean = 0.28 (s.d. = 0.08) to 0.73 (0.23). Lake Erie typically displayed the lowest egg mercury levels, 0.18 (0.08) to 0.24 (0.11). Overall, mercury levels ranged from 0.12 (0.02) in 1985 to 0.88 (0.23) in 1982 for Channel-Shelter Island (Lake Huron) and Pigeon Island (Lake Ontario), respectively. Generally, all colony sites showed peak mercury levels in 1982. A significant decline in egg mercury levels was observed in six colony sites between 1972 and 1992 and in three colony sites between 1981 and 1992. The mean herring gull egg mercury levels observed in the early and mid 1970s and in 1982 for some colony sites were within the range found which potentially reduces hatchability in other fish-eating bird species.

  1. [Demonstration of the existence of a marine cycle in the strigeides: Cardiocephalus longicollis Szidat, 1928 (Trematoda: Strigeidae)].

    PubMed

    Prevot, G; Bartoli, P

    1980-01-01

    During their investigations on parasitism of fishes and birds in the lagoon of Brusc (Var), the authors have discovered the life cycle of Cardiocephalus longicollis. Cercariae of pharyngeate furcocercous type develop in sporocysts in the digestive gland of the marine prosobranch Nassa corniculum. The cercaria is identified as Cercaria nassae (Dolgikh, 1965) from Nassa reticulata in Black sea; it closely resembles Cercaria nassa (Martin, 1945) from Ilyanassa obsolseta (syn. Nassa obsoleta) at Woods Hole (U.S.A.). Several intermediate hosts have been related; they are the marine fishes Diplodus annularis, D. vulgaris, Boops salpa, Pagellus mormyrus (Sparidae) and Belone belone (Scombresocidae). Metacercariae of tetracotyle type were found in the cavity of optical lobes of the brain. Experimental contamination of fishes: Potamoschistus microps, Blennius sp., Mugil cephalus and Syngnathus abaster has been negative; that of Diplodus annularis and D. sargus, positive. It allowed to follow the development from cercaria to tetracotyle. In Provence natural definitive hosts are Larus argentatus and L. ribidundus; contaminations of these birds with metacercariae experimentally raised in Diplodus annularis and D. vulgaris were successfull. Some observations are pointed out especially the development of the parasite in the definitive host, the organisation of tribocytic organ and the geographical distribution of the parasite.

  2. Biological impact of eutrophication in the bay of somme and the induction and impact of anoxia

    NASA Astrophysics Data System (ADS)

    Desprez, M.; Rybarczyk, H.; Wilson, J. G.; Ducrotoy, J. P.; Sueur, F.; Olivesi, R.; Elkaim, B.

    The first effects of eutrophication in the Bay of Somme became apparent in the years 1982-1985, when the cockle population collapsed. Areas of high mortality were mapped. Following exceptionally high summer temperatures, other effects were seen in 1982, 1983 and 1989, notably a mass mortality of the benthos. It appeared that the mortality of the benthos was a direct result of anoxia in the water promoted by phytoplankton blooms which were due to high nitrogen levels (nitrates from river and land runoff; ammonium from estuarine bivalve populations). Effects from the change in the benthic community (the disappearance of Cerastoderma edule and the proliferation of Pygospio elegans) were also apparent higher up in the food chain, viz. changes in the diet of the two main predators of the bivalve, the oystercatcher ( Haematopus ostralegus) and the common gull ( Larus canus). Following respirometry measurements of the water, sediment and the major macrobenthic species ( Cerastoderma edule, Macoma balthica, Nereis diversicolor, Hydrobia ulvae), a model for anoxia was constructed.

  3. Tracking the History and Ecological Changes of Rising Double-Crested Cormorant Populations Using Pond Sediments from Islands in Eastern Lake Ontario

    PubMed Central

    Stewart, Emily M.; Michelutti, Neal; Shenstone-Harris, Sarah; Grooms, Christopher; Weseloh, Chip; Kimpe, Linda E.; Blais, Jules M.; Smol, John P.

    2015-01-01

    In the Laurentian Great Lakes region, the double-crested cormorant (Phalacrocorax auritus) has seen a thousand-fold population increase in recent decades. These large colonies of birds now often conflict with socioeconomic interests, particularly due to perceived competition with fisheries and the destruction of terrestrial vegetation in nesting habitats. Here we use dated sediment cores from ponds on islands in eastern Lake Ontario that receive waste inputs from dense colonies of cormorants and ring-billed gulls (Larus delawarensis) to chronicle the population rise of these species and assess their long-term ecological impacts. Modern water chemistry sampling from these sites reveals drastically elevated nutrient and major ion concentrations compared to reference ponds not influenced by waterbirds. Geochemical tracers in dated sediment cores, particularly δ15N and chlorophyll-a concentrations, track waterbird influences over time. Fossil diatom assemblages were dominated by species tolerant of hyper-eutrophic and polluted systems, which is in marked contrast to assemblages in reference sites. In addition to establishing long-term ecological impacts, this multi-proxy paleoecological approach can be used to determine whether islands of concern have been long-term nesting sites or were only recently colonized by cormorant or ring-billed gull populations across the Great Lakes, facilitating informed management decisions about controversial culling programs. PMID:26214177

  4. Anthropogenic debris in the nests of kelp gulls in South Africa.

    PubMed

    Witteveen, Minke; Brown, Mark; Ryan, Peter G

    2017-01-30

    Anthropogenic debris results in detrimental interactions with many marine species. Several seabirds include debris items in their nests, which can lead to entanglement of chicks and adults, resulting in injury or death. Anthropogenic debris was found in 4-67% of kelp gull Larus dominicanus nests in seven colonies in the Western Cape, South Africa. Nests contained two types of litter: items included in the nest structure during construction (mainly ropes and straps), and regurgitated items (mainly bags and food wrappers) that probably accumulate primarily during the chick-rearing period. Debris used in nest construction was more likely to injure gulls, and was found mainly at coastal sites where there was little natural vegetation for construction. Distance to the nearest urban waste landfill significantly affected the occurrence of debris items in nests, especially dietary-derived items. The amount of debris in kelp gull nests highlights the need for improved debris management in South Africa. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Strategies for nest-site selection by king eiders

    USGS Publications Warehouse

    Bentzen, R.L.; Powell, A.N.; Suydam, R.S.

    2009-01-01

    Nest site selection is a critical component of reproduction and has presumably evolved in relation to predation, local resources, and microclimate. We investigated nest-site choice by king eiders (Somateria spectabilis) on the coastal plain of northern Alaska, USA, 2003-2005. We hypothesized that nest-site selection is driven by predator avoidance and that a variety of strategies including concealment, seclusion, and conspecific or inter-specific nest defense might lead to improved nesting success. We systematically searched wetland basins for king eider nests and measured habitat and social variables at nests (n = 212) and random locations (n = 493). King eiders made use of both secluded and concealed breeding strategies; logistic regression models revealed that females selected nests close to water, on islands, and in areas with high willow (Salix spp.) cover but did not select sites near conspecific or glaucous gull (Larus hyperboreus) nests. The most effective nest-placement strategy may vary depending on density and types of nest predators; seclusion is likely a mammalian-predator avoidance tactic whereas concealment may provide protection from avian predators. We recommend that managers in northern Alaska attempt to maintain wetland basins with islands and complex shorelines to provide potential nest sites in the vicinity of water. ?? The Wildlife Society.

  6. Replication of 2 subtypes of low-pathogenicity avian influenza virus of duck and gull origins in experimentally infected Mallard ducks.

    PubMed

    Daoust, P-Y; van de Bildt, M; van Riel, D; van Amerongen, G; Bestebroer, T; Vanderstichel, R; Fouchier, R A M; Kuiken, T

    2013-05-01

    Many subtypes of low-pathogenicity avian influenza (LPAI) virus circulate in wild bird reservoirs, but their prevalence may vary among species. We aimed to compare by real-time reverse-transcriptase polymerase chain reaction, virus isolation, histology, and immunohistochemistry the distribution and pathogenicity of 2 such subtypes of markedly different origins in Mallard ducks (Anas platyrhynchos): H2N3 isolated from a Mallard duck and H13N6 isolated from a Ring-billed Gull (Larus delawarensis). Following intratracheal and intraesophageal inoculation, neither virus caused detectable clinical signs, although H2N3 virus infection was associated with a significantly decreased body weight gain during the period of virus shedding. Both viruses replicated in the lungs and air sacs until approximately day 3 after inoculation and were associated with a locally extensive interstitial, exudative, and proliferative pneumonia. Subtype H2N3, but not subtype H13N6, went on to infect the epithelia of the intestinal mucosa and cloacal bursa, where it replicated without causing lesions until approximately day 5 after inoculation. Larger quantities of subtype H2N3 virus were detected in cloacal swabs than in pharyngeal swabs. The possible clinical significance of LPAI virus-associated pulmonary lesions and intestinal tract infection in ducks deserves further evaluation.

  7. Molecular characterization of Giardia intestinalis haplotypes in marine animals: variation and zoonotic potential.

    PubMed

    Lasek-Nesselquist, Erica; Bogomolni, Andrea L; Gast, Rebecca J; Welch, David Mark; Ellis, Julie C; Sogin, Mitchell L; Moore, Michael J

    2008-08-19

    Giardia intestinalis is a microbial eukaryotic parasite that causes diarrheal disease in humans and other vertebrates worldwide. The negative effect on quality of life and economics caused by G. intestinalis may be increased by its potential status as a zoonosis, or a disease that can be transmitted from animals to humans. The zoonotic potential of G. intestinalis has been implied for over 2 decades, with human-infecting genotypes (belonging to the 2 major subgroups, Assemblages A and B) occurring in wildlife and domesticated animals. There are recent reports of G. intestinalis in shellfish, seals, sea lions and whales, suggesting that marine animals are also potential reservoirs of human disease. However, the prevalence, genetic diversity and effect of G. intestinalis in marine environments and the role that marine animals play in transmission of this parasite to humans are relatively unexplored. Here, we provide the first thorough molecular characterization of G. intestinalis in marine vertebrates. Using a multi-locus sequencing approach, we identify human-infecting G. intestinalis haplotypes of both Assemblages A and B in the fecal material of dolphins, porpoises, seals, herring gulls Larus argentatus, common eiders Somateria mollissima and a thresher shark Alopias vulpinus. Our results indicate that G. intestinalis is prevalent in marine ecosystems, and a wide range of marine hosts capable of harboring zoonotic forms of this parasite exist. The presence of G. intestinalis in marine ecosystems raises concerns about how this disease might be transmitted among different host species.

  8. Detection of a novel Rickettsia sp. in soft ticks (Acari: Argasidae) in Algeria.

    PubMed

    Lafri, Ismail; Leulmi, Hamza; Baziz-Neffah, Fadhila; Lalout, Reda; Mohamed, Chergui; Mohamed, Karakallah; Parola, Philippe; Bitam, Idir

    2015-01-01

    Argasid ticks are vectors of viral and bacterial agents that can infect humans and animals. In Africa, relapsing fever borreliae are neglected arthropod-borne pathogens that cause mild to deadly septicemia and miscarriage. It would be incredibly beneficial to be able to simultaneous detect and identify other pathogens transmitted by Argasid ticks. From 2012 to 2014, we conducted field surveys in 4 distinct areas of Algeria. We investigated the occurrence of soft ticks in rodent burrows and yellow-legged gull (Larus michahellis) nests in 10 study sites and collected 154 soft ticks. Molecular identification revealed the occurrence of two different soft tick genera and five species, including Carios capensis in yellow-legged gull nests and Ornithodoros occidentalis, Ornithodoros rupestris, Ornithodoros sonrai, Ornithodoros erraticus in rodent burrows. Rickettsial DNA was detected in 41/154, corresponding to a global detection rate of 26.6%. Sequences of the citrate synthase (gltA) gene suggest that this agent is a novel spotted fever group Rickettsia. For the first time in Algeria, we characterize a novel Rickettsia species by molecular means in soft ticks. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  9. Climate variability and temporal trends of persistent organic pollutants in the arctic: a study of glaucous gulls.

    PubMed

    Bustnes, Jan O; Gabrielsen, Geir W; Verreault, Jonathan

    2010-04-15

    The impact of climate variability on temporal trends (1997-2006) of persistent organic pollutants (POPs; polychlorinated biphenyls [PCB], hexachlorobenzene [HCB], and oxychlordane) was assessed in glaucous gulls (Larus hyperboreus) breeding in the Norwegian Arctic (n = 240). The Arctic Oscillation (AO: an index of sea-level pressure variability in the Northern Hemisphere above 20 degrees N) with different time lags was used as a climate proxy. The estimated concentrations of POPs in glaucous gull blood/plasma declined substantially (16-60%) over the time period. Multiple regression analyses showed that the rates of decline for POPs were correlated to climate variation when controlling for potential confounding variables (sex and body condition). More specifically AO in the current winter showed negative associations with POP concentrations, whereas the relationships with AO measurements from the year preceding POP measurements (AO preceding summer and AO preceding winter) were positive. Hence, gulls had relatively higher POP concentrations in breeding seasons following years with high air transport toward the Arctic. Furthermore, the impact of AO appeared to be stronger for HCB, a relatively volatile compound with high transport potential, compared to heavy chlorinated PCB congeners. This study thus suggests that predicted climate change should be considered in assessments of future temporal trends of POPs in Arctic wildlife.

  10. 'Flying barnacles': implications for the spread of non-indigenous species.

    PubMed

    Tøttrup, Anders P; Chan, Benny K K; Koskinen, Hannu; Høeg, Jens T

    2010-07-01

    The presence of adult barnacles of Fistulobalanus pallidus (Darwin) and Fistulobalanus albicostatus (Pilsbry) attached to field-readable plastic leg rings on the Lesser Black-backed Gull Larus fuscus in Northern Europe is reported. L. fuscus is a long-distance palaearctic migrant, breeding in temperate areas spreading widely over inland and marine habitats outside the breeding season. The species is known to perform long-distance migration to Africa and the Middle East. Combining present knowledge on the birds' migratory pattern and the home range of the barnacle species, it is concluded that the cypris larvae of F. pallidus must have settled in African waters, whereas the area where F. albicostatus settled on the bird leg rings is less certain. The barnacles were of adult size and must thus have been attached for a period of no less than 2 months. More than 30 individual barnacles could occur together on a single field-readable plastic leg ring. The barnacles could therefore, if ported alive to a new area, reproduce successfully and thus either introduce the species or genetically affect other native populations. This may pose a new and wholly unexpected transportation pathway for barnacles as invasive species.

  11. Erysipelothrix rhusiopathiae isolated from gull-inflicted wounds in southern right whale calves.

    PubMed

    Fiorito, Carla D; Bentancor, Adriana; Lombardo, Daniel; Bertellotti, Marcelo

    2016-08-31

    Southern right whales Eubalaena australis from Peninsula Valdés, Argentina, show wounds produced by kelp gulls Larus dominicanus that feed on the whales' dorsal skin and blubber. During the 2013 whale season, several calves were reported showing kelp gull injuries with a swollen area surrounded by rhomboid-shaped raised edges. Samples from 9 calves were taken in order to establish the etiology of these rhomboid-shaped wounds; 2 calves (one living, one dead) showed gull-inflicted injuries with rhomboid-shaped edges. Samples from the dead calf were histologically characterized by the presence of dermal congestion, suppurative dermatitis and panniculitis, necrotizing vasculitis and vascular thrombosis. Erysipelothrix rhusiopathiae was detected by culture and PCR in samples from both calves. In this study we report, for the first time to our knowledge, the isolation of E. rhusiopathiae from wounds produced by gull attacks on southern right whale calves, supplying evidence that these wounds may act as an entry route for pathogens. This work provides new information about the consequences of gull-inflicted injuries for whale health.

  12. Roost site selection by ring-billed and herring gulls

    USGS Publications Warehouse

    Clark, Daniel E.; Destefano, Stephen; MacKenzie, Kenneth G.; Koenen, Kiana K. G.; Whitney, Jillian J.

    2016-01-01

    Gulls (Larus spp.) commonly roost in large numbers on inland and coastal waters, yet there is little information on how or where gulls choose sites for roosting. Roost site selection can lead to water quality degradation or aviation hazards when roosts are formed on water supply reservoirs or are close to airports. Harassment programs are frequently initiated to move or relocate roosting gulls but often have mixed results because gulls are reluctant to leave or keep returning. As such, knowledge of gull roost site selection and roosting ecology has applied and ecological importance. We used satellite telemetry and an information-theoretic approach to model seasonal roost selection of ring-billed (L. delawarensis) and herring gulls (L. argentatus) in Massachusetts, USA. Our results indicated that ring-billed gulls preferred freshwater roosts and will use a variety of rivers, lakes, and reservoirs. Herring gulls regularly roosted on fresh water but used salt water roosts more often than ring-billed gulls and also roosted on a variety of land habitats. Roost modeling showed that herring and ring-billed gulls selected inland fresh water roosts based on size of the water body and proximity to their last daytime location; they selected the largest roost closest to where they ended the day. Management strategies to reduce or eliminate roosting gulls could identify and try to eliminate other habitat variables (e.g., close-by foraging sites) that are attracting gulls before attempting to relocate or redistribute (e.g., through hazing programs) roosting birds.

  13. Prevalence and characterization of Salmonella spp. among marine animals in the Channel Islands, California.

    PubMed

    Stoddard, R A; DeLong, R L; Byrne, B A; Jang, S; Gulland, Frances M D

    2008-08-19

    Salmonella enterica is a zoonotic pathogen that has been isolated from free-ranging marine mammals throughout the world, with animals in the Channel Islands of California (USA) showing the highest prevalence. The goal of this study was to determine prevalence, antimicrobial sensitivity and genetic similarity using pulsed-field gel electrophoresis (PFGE) of Salmonella in several non-domestic animal species on San Miguel and San Nicolas Islands. Fecal samples were collected from 90 California sea lion Zalophus californianus pups, 30 northern elephant seal Mirounga angustirostris pups and 87 western gulls Larus occidentalis in the Channel Islands and 59 adult male sea lions in Puget Sound, WA (USA). Salmonella were isolated, identified and serotyped, followed by antimicrobial susceptibility testing and PFGE. Of the California sea lion pups that were sampled on the islands, 21% (n = 19) were positive for Salmonella, whereas no adults males in Puget Sound were positive. Of the northern elephant seal pups sampled, 87% (n = 26) were harboring Salmonella. Only 9% (n = 8) of western gulls were shedding Salmonella, with one of these gulls harboring the only antimicrobial resistant isolate. The serotypes found in these animals were Enteritidis, Montevideo, Newport, Reading, and Saint Paul. The only serotype that showed variation on PFGE was Newport. The pinnipeds of the Channel Islands harbor Salmonella at a higher prevalence than pinnipeds from other geographic areas observed in previous studies. Researchers and veterinarians should exercise increased caution when working with these animals due to the zoonotic potential of Salmonella.

  14. Predation on seabirds by red foxes at Shaiak Island, Alaska

    USGS Publications Warehouse

    Petersen, M.R.

    1982-01-01

    Two Red Foxes (Vulpes fulva) that invaded Shaiak Island before the 1976 nesting season had a marked impact on the nesting success of five of seven species of seabirds breeding on the island that year. Common Eiders (Somateria mollissima), Glaucous-winged Gulls (Larus glaucescens), and Common Murres (Uria aalge), that nest in areas accessible to foxes, did not raise any young to fledging. Double-crested Cormorants (Phalacrocorax auritus) were only slightly more successful; 13 (4.3%) of 300 pairs raised one or more young to fledging. Evidence suggested that 21 (35.6%) of 62 pairs of Tufted Puffins (Lunda cirrhata) lost eggs or chicks to foxes, and foxes killed at least 13 (8.3%) of 156 adult puffins on ten sample plots. Conversely, Black-Legged Kittiwakes (Rissa tridactyla) and Pelagic Cormorants (Phalacrocorax pelagicus), which nested primarily on cliffs inaccessible to foxes, lost very few nests. There was no apparent change in general nest site selections by seabirds the following year, when foxes were no longer present. Any avoidance by birds of areas vulnerable to fox predation would probably be discernible only after several years of continuous predation.

  15. Amino acid specific stable nitrogen isotope values in avian tissues: Insights from captive American kestrels and wild herring gulls

    USGS Publications Warehouse

    Hebert, Craig E.; Popp, B.N.; Fernie, K.J.; Ka'apu-Lyons, C.; Rattner, Barnett A.; Wallsgrove, N.

    2016-01-01

    Through laboratory and field studies, the utility of amino acid compound-specific nitrogen isotope analysis (AA-CSIA) in avian studies is investigated. Captive American kestrels (Falco sparverius) were fed an isotopically characterized diet and patterns in δ15N values of amino acids (AAs) were compared to those in their tissues (muscle and red blood cells) and food. Based upon nitrogen isotope discrimination between diet and kestrel tissues, AAs could mostly be categorized as source AAs (retaining baseline δ15N values) and trophic AAs (showing 15N enrichment). Trophic discrimination factors based upon the source (phenylalanine, Phe) and trophic (glutamic acid, Glu) AAs were 4.1 (muscle) and 5.4 (red blood cells), lower than those reported for metazoan invertebrates. In a field study involving omnivorous herring gulls (Larus argentatus smithsonianus), egg AA isotopic patterns largely retained those observed in the laying female’s tissues (muscle, red blood cells, and liver). Realistic estimates of gull trophic position were obtained using bird Glu and Phe δ15N values combined with β values (difference in Glu and Phe δ15N in primary producers) for aquatic and terrestrial food webs. Egg fatty acids were used to weight β values for proportions of aquatic and terrestrial food in gull diets. This novel approach can be applied to generalist species that feed across ecosystem boundaries.

  16. Influence of a mine tailing accident near Doñana National Park (Spain) on heavy metals and arsenic accumulation in 14 species of waterfowl (1998 to 2000).

    PubMed

    Gómez, G; Baos, R; Gómara, B; Jiménez, B; Benito, V; Montoro, R; Hiraldo, F; González, M J

    2004-11-01

    This article presents the impact on waterbirds in Doñana National Park (Spain) of an accidental release of 5 million m3 acid waste produced by the processing of pyrite ore. Heavy metals (zinc, copper, cadmium, and lead) and arsenic were measured in several soft tissues (liver, kidney, and muscle) taken from 14 waterfowl species collected between April 1998 and May 2000. The main source of copper and zinc found in the waterfowl species examined was the spill waste, whereas cadmium, lead, and arsenic could also came from other sources. Kidney was the primary organ for cadmium and lead accumulation, whereas liver accumulated the most zinc and copper. Arsenic was concentrated in both muscle and liver tissue. The degree of contamination of the area where the birds lived, their age, their sex their size, and the time since the spill were found to have less influence than species and trophic level on the accumulation of metal in organs and tissues. Four species (Anser anser, Ciconia ciconia, Larus ridibundus, and Porphyrio porphyrio) were found to have the highest levels of the 5 elements.

  17. Effects of a small seagull colony on trophic status and primary production in a Mediterranean coastal system (Marinello ponds, Italy)

    NASA Astrophysics Data System (ADS)

    Signa, Geraldina; Mazzola, Antonio; Vizzini, Salvatrice

    2012-10-01

    Colonies of seabirds have been shown to influence nutrient cycling and primary production of coastal areas, but knowledge is still limited above all for smaller colonies. This study evaluates the influence of a small resident seagull colony (Larus michahellis Naumann, 1840) on a Mediterranean coastal system (Marinello ponds, Sicily, Italy). The presence of ornithogenic organic matter from seagull guano was first assessed at increasing distances from the colony using δ15N to indicate the effects of guano on the trophic status and primary production. The pond directly affected by guano deposition showed an anomalous water and sediment chemistry, especially regarding physico-chemical variables (pH), nitrogen isotopic signature, nutrient balance and phytoplankton biomass. These effects were not observed in the adjacent ponds, highlighting pronounced, small spatial-scale variability. Given the worldwide presence of seabird colonies and the scarcity of research on their effect on coastal marine areas, the study shows that seabird-mediated input may be important in influencing ecosystem dynamics of coastal areas, even where both the system in question and the colony are small.

  18. Differential response of two Pinus spp. to avian nitrogen input as revealed by nitrogen isotope analysis for tree rings.

    PubMed

    Mizota, Chitoshi; Lopez Caceres, Maximo Larry; Yamanaka, Toshiro; Nobori, Yoshihiro

    2011-03-01

    Temporal variations in N concentration and δ(15)N value of annual tree rings (1 year of time resolution) of two Japanese Black Pine (Pinus thunbergii) and three Japanese Red Pine (Pinus densiflora) trees under current breeding activity of the Great Cormorant (Pharacrocorax carbo) and the Black-tailed Gull (Larus crassirostris), respectively, in central and northeastern Japan were studied. Both species from control sites where no avian input occurs show negative values (δ(15)N = around -4 ‰ to -2 ‰) which are common among higher plants growing under high rainfall regimes. The δ(15)N values of P. densiflora show uniformly positive values several years before and after the breeding event, indicating N translocation that moved the absorbed N of a given growth year to tree rings of the previous year while a clear historical value of soil N dynamics was kept intact in the annual rings of P. thunbergii. Long-term N trends inferred from tree rings must take into account tree species with limited translocation rates that can retain actual N annual acquisition.

  19. Kelp and dolphin gulls cause perineal wounds in South American fur seal pups (Arctocephalus australis) at Guafo Island, Chilean Patagonia

    PubMed Central

    Muñoz, Francisco; Montalva, Felipe; Perez-Venegas, Diego; Pavés, Héctor; Gottdenker, Nicole

    2017-01-01

    During five reproductive seasons, we documented the presence, extent and origin of perineal wounds in South American fur seal pups (Arctocephalus australis) on Guafo Island, Northern Chilean Patagonia. The seasonal prevalence of perineal wounds ranged from 5 to 9%, and new cases were more common at the end of the breeding season (February), when pups were on average two months old and were actively expelling hookworms (Uncinaria sp). Histologically, wounds corresponded to marked ulcerative lymphoplasmacytic and histiocytic dermatitis with granulation tissue and mixed bacterial colonies. In 2015 and 2017, kelp gulls (Larus dominicanus) and dolphin gulls (Leucophaeus scoresbii) were observed picking and wounding the perineal area of marked pups. This behaviour occurred more frequently after the pups' defecation, when sea gulls engaged in consumption of pups' faeces. The affected pups usually had moderate to marked hookworm infections along with bloody diarrhoea and anaemia. Pups with severe wounds (23% of affected animals) had swollen perineal areas and signs of secondary systemic bacterial infection. We propose that seagulls on Guafo Island have learned to consume remains of blood and parasites in the faeces of pups affected by hookworm infection, causing perineal wounds during this process. We conclude that this perineal wounding is an unintentional, occasional negative effect of an otherwise commensal gull–fur seal relationship. PMID:28791178

  20. Kelp and dolphin gulls cause perineal wounds in South American fur seal pups (Arctocephalus australis) at Guafo Island, Chilean Patagonia.

    PubMed

    Seguel, Mauricio; Muñoz, Francisco; Montalva, Felipe; Perez-Venegas, Diego; Pavés, Héctor; Gottdenker, Nicole

    2017-07-01

    During five reproductive seasons, we documented the presence, extent and origin of perineal wounds in South American fur seal pups (Arctocephalus australis) on Guafo Island, Northern Chilean Patagonia. The seasonal prevalence of perineal wounds ranged from 5 to 9%, and new cases were more common at the end of the breeding season (February), when pups were on average two months old and were actively expelling hookworms (Uncinaria sp). Histologically, wounds corresponded to marked ulcerative lymphoplasmacytic and histiocytic dermatitis with granulation tissue and mixed bacterial colonies. In 2015 and 2017, kelp gulls (Larus dominicanus) and dolphin gulls (Leucophaeus scoresbii) were observed picking and wounding the perineal area of marked pups. This behaviour occurred more frequently after the pups' defecation, when sea gulls engaged in consumption of pups' faeces. The affected pups usually had moderate to marked hookworm infections along with bloody diarrhoea and anaemia. Pups with severe wounds (23% of affected animals) had swollen perineal areas and signs of secondary systemic bacterial infection. We propose that seagulls on Guafo Island have learned to consume remains of blood and parasites in the faeces of pups affected by hookworm infection, causing perineal wounds during this process. We conclude that this perineal wounding is an unintentional, occasional negative effect of an otherwise commensal gull-fur seal relationship.

  1. Depredation of common eider, Somateria mollissima, nests on a central Beaufort Sea barrier island: A case where no one wins

    USGS Publications Warehouse

    Reed, J.A.; Lacroix, D.L.; Flint, P.L.

    2007-01-01

    Along the central Beaufort Sea, Pacific Common Eiders (Somateria mollissima v-nigra) nest on unvegetated, barrier islands; often near nesting Glaucous Gulls (Larus hyperboreus). Nest-site choice likely reflects a strategy of predator avoidance: nesting on islands to avoid mammalian predators and near territorial gulls to avoid other avian predators. We observed a nesting colony of Common Eiders from first nest initiation through nesting termination on Egg Island near Prudhoe Bay, Alaska (2002 - 2003). Resident gulls depredated many eider nests, mostly during initiation. All nests failed when an Arctic Fox (Alopex lagopus) visited the island and flushed hens from their nests, exposing the eggs to depredation by the fox and gulls (resident and non-resident). Common Eiders actively defended nests from gulls, but not from foxes. Likely all three species (i.e., eiders, gulls, and foxes) ultimately achieved negligible benefit from their nest-site selection or predatory activity: (a) island nesting provided no safety from mammalian predators for eiders or gulls, (b) for Common Eiders, nesting near gulls increased egg loss, (c) for Glaucous Gulls, nesting near colonial eiders may have reduced nest success by attracting the fox, and (d) for Arctic Foxes, the depredation was of questionable value, as most eggs were cached and probably not recoverable (due to damage from fall storms). Thus, the predator-prey interactions we observed appear to be a case where little or no fitness advantage was realized by any of the species involved.

  2. The herring gull complex is not a ring species.

    PubMed Central

    Liebers, Dorit; de Knijff, Peter; Helbig, Andreas J.

    2004-01-01

    Under what circumstances speciation in sexually reproducing animals can occur without geographical disjunction is still controversial. According to the ring-species model, a reproductive barrier may arise through 'isolation by distance' when peripheral populations of a species meet after expanding around some uninhabitable barrier. The classical example of this kind of speciation is the herring gull (Larus argentatus) complex, with a circumpolar distribution in the Northern Hemisphere. Based on mitochondrial DNA variation among 21 gull taxa, we show that members of this complex differentiated largely in allopatry following multiple vicariance and long-distance-colonization events, not primarily through isolation by distance. Reproductive isolation evolved more rapidly between some lineages than between others, irrespective of their genetic distance. Extant taxa are the result of divergent as well as reticulate evolution between two ancestral lineages originally separated in a North Atlantic refugium and a continental Eurasian refugium, respectively. Continental birds expanded along the entire north Eurasian coast and via Beringia into North America. Contrary to the ring-species model, we find no genetic evidence for a closure of the circumpolar ring through colonization of Europe by North American herring gulls. However, closure of the ring in the opposite direction may be imminent, with lesser black-backed gulls about to colonize North America. PMID:15255043

  3. Perfluoroalkyl and polyfluoroalkyl substances in entire clutches of Audouin's gulls from the Ebro Delta.

    PubMed

    Vicente, Joana; Sanpera, Carola; García-Tarrasón, Manuel; Pérez, Alba; Lacorte, Silvia

    2015-01-01

    The aim of the present study was to determine the distribution of per- and polyfluoroalkyl substances (PFASs) in three-egg clutches of Audouin's gull (Larus audouinii) breeding in Ebro Delta's colony according to the laying order (a, b and c eggs). Five PFASs were analyzed in 30 eggs (yolk and albumen separately), corresponding to 10 three-egg clutches. Carbon and nitrogen stable isotopes were measured as dietary tracers. PFASs were not detected in albumen. In egg yolks, perfluorooctane sulfonate (PFOS) was the main compound detected followed by perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHS) and perfluorooctanoic acid (PFOA). Perfluorooctane sulfonate (PFBS) was not detected. Mean ΣPFASs for a-eggs was of 236±57 ng g(-1) yolk wet weight (ww), for b-eggs was of 140±56 ng g(-1) yolk ww and for c-eggs, 133±54 ng g(-1) yolk ww. PFOS concentration decreased according to the laying order of the eggs, showing significant differences between consecutive eggs. In addition, significant correlation (rs2=0.7-0.9) was observed for PFOS concentration within the eggs from the same clutch. No relationship was found between PFOS levels and stable isotopes signatures. Capsule: In Audouin gull's eggs, PFOS was the main PFASs detected and its concentration decreased according to the laying sequence.

  4. A PELAGIC OUTBREAK OF AVIAN CHOLERA IN NORTH AMERICAN GULLS: SCAVENGING AS A PRIMARY MECHANISM FOR TRANSMISSION?

    PubMed

    Wille, Michelle; McBurney, Scott; Robertson, Gregory J; Wilhelm, Sabina I; Blehert, David S; Soos, Catherine; Dunphy, Ron; Whitney, Hugh

    2016-10-01

    Avian cholera, caused by the bacterium Pasteurella multocida , is an endemic disease globally, often causing annual epizootics in North American wild bird populations with thousands of mortalities. From December 2006 to March 2007, an avian cholera outbreak caused mortality in marine birds off the coast of Atlantic Canada, largely centered 300-400 km off the coast of the island of Newfoundland. Scavenging gulls ( Larus spp.) were the primary species detected; however, mortality was also identified in Black-legged Kittiwakes ( Rissa tridactyla ) and one Common Raven ( Corvus corax ), a nonmarine species. The most common gross necropsy findings in the birds with confirmed avian cholera were acute fibrinous and necrotizing lesions affecting the spleen, air sacs, and pericardium, and nonspecific hepatomegaly and splenomegaly. The etiologic agent, P. multocida serotype 1, was recovered from 77 of 136 carcasses examined, and confirmed or probable avian cholera was diagnosed in 85 cases. Mortality observed in scavenging gull species was disproportionately high relative to their abundance, particularly when compared to nonscavenging species. The presence of feather shafts in the ventricular lumen of the majority of larid carcasses diagnosed with avian cholera suggests scavenging of birds that died from avian cholera as a major mode of transmission. This documentation of an outbreak of avian cholera in a North American pelagic environment affecting primarily scavenging gulls indicates that offshore marine environments may be a component of avian cholera dynamics.

  5. Investigation of outbreaks of highly pathogenic H5N1 avian influenza in waterfowl and wild birds in Hong Kong in late 2002.

    PubMed

    Ellis, Trevor M; Bousfield, R Barry; Bissett, Lucy A; Dyrting, Kitman C; Luk, Geraldine S M; Tsim, S T; Sturm-Ramirez, Katharine; Webster, Robert G; Guan, Yi; Malik Peiris, J S

    2004-10-01

    Outbreaks of highly pathogenic H5N1 avian influenza have occurred in Hong Kong in chickens and other gallinaceous poultry in 1997, 2001, twice in 2002 and 2003. High mortality rates were seen in gallinaceous birds but not in domestic or wild waterfowl or other wild birds until late 2002 when highly pathogenic H5N1 avian influenza occurred in waterfowl (geese, ducks and swans), captive Greater Flamingo (Phoenicopterus ruber) and other wild birds (Little Egret Egretta garzetta) at two waterfowl parks and from two dead wild Grey Heron (Ardea cinerea) and a Black-headed Gull (Larus ridibundus) in Hong Kong. H5N1 avian influenza virus was also isolated from a dead feral pigeon (Columba livia) and a dead tree sparrow (Passer montanus) during the second outbreak. The first waterfowl outbreak was controlled by immediate strict quarantine and depopulation 1 week before the second outbreak commenced. Control measures implemented for the second outbreak included strict isolation, culling, increased sanitation and vaccination. Outbreaks in gallinaceous birds occurred in some live poultry markets concurrently with the second waterfowl outbreak, and infection on a chicken farm was detected 1 week after the second waterfowl park outbreak was detected, on the same day the second grey heron case was detected. Subsequent virus surveillance showed the outbreaks had been contained.

  6. Avian embryonic development does not change the stable isotope composition of the calcite eggshell.

    PubMed

    Maurer, G; Portugal, S J; Boomer, I; Cassey, P

    2011-01-01

    The avian embryo resorbs most of the calcium for bone formation from the calcite eggshell but the exact mechanisms of the resorption are unknown. The present study tested whether this process results in variable fractionation of the oxygen and carbon isotopes in shell calcium carbonate, which could provide a detailed insight into the temporal and spatial use of the eggshell by the developing embryo. Despite the uncertainty regarding changes in stable isotope composition of the eggshell across developmental stages or regions of the shell, eggshells are a popular resource for the analysis of historic and extant trophic relationships. To clarify how the stable isotope composition varies with embryonic development, the δ(13)C and δ(18)O content of the carbonate fraction in shells of black-headed gull (Larus ridibundus) eggs were sampled at four different stages of embryonic development and at five eggshell regions. No consistent relationship between the stable isotope composition of the eggshell and embryonic development, shell region or maculation was observed, although shell thickness decreased with development in all shell regions. By contrast, individual eggs differed significantly in isotope composition. These results establish that eggshells can be used to investigate a species' carbon and oxygen sources, regardless of the egg's developmental stage.

  7. Synanthropic birds and parasites.

    PubMed

    Dipineto, Ludovico; Borrelli, Luca; Pepe, Paola; Fioretti, Alessandro; Caputo, Vincenzo; Cringoli, Giuseppe; Rinaldi, Laura

    2013-12-01

    This paper describes the parasitologic findings for 60 synanthropic bird carcasses recovered in the Campania region of southern Italy. Birds consisted of 20 yellow-legged gulls (Larus michahellis), 15 rock pigeons (Columba livia), 15 common kestrels (Falco tinnunculus), and 10 carrion crows (Corvus corone). Each carcass was examined to detect the presence of ectoparasites and then necropsied to detect helminths. Ectoparasites occurred in 100% of the birds examined. In particular, chewing lice were recovered with a prevalence of 100%, whereas Pseudolynchia canariensis (Hippoboscidae) were found only in pigeons with a prevalence of 80%. Regarding endoparasites, a total of seven helminth species were identified: three nematodes (Ascaridia columbae, Capillaria columbae, Physaloptera alata), one cestoda (Raillietina tetragona), one trematoda (Cardiocephalus longicollis), and two acanthocephalans (Centrorhynchus globocaudatus and Centrorhynchus buteonis). The findings of the present study add data to the parasitologic scenario of synanthropic birds. This is important because parasitic infection can lead to serious health problems when combined with other factors and may affect flying performance and predatory effectiveness.

  8. Interpreting temporal trends in Great Lakes organochlorine levels: Results from the herring gull surveillance program

    SciTech Connect

    Hebert, C.E.; Shutt, J.L.; Norstrom, R.J.; Weseloh, D.V.

    1995-12-31

    The Canadian Wildlife Service`s herring gull (Larus argentatus) surveillance program has demonstrated the utility of this species as a monitor of spatial and temporal trends in Great Lakes contaminant levels. Organochlorine concentrations in herring gull eggs decreased significantly in the 1970s and early 1980s as a result of control measures. Since the mid-1980s, however, concentrations of many compounds have been relatively constant. In addition, periodic fluctuations in egg contaminant concentrations hamper the ability to interpret more recent temporal trends in organochlorine levels. To evaluate the progress towards achieving the virtual elimination of organochlorines from the Great Lakes the authors must improve their understanding of the factors which regulate organochlorine bioaccumulation. This is particularly important for those species which have been selected as key indicators of ecosystem contamination, such as the herring gull. The goal of this paper is to examine some of the factors which may be responsible for the temporal fluctuations in herring gull egg contaminant concentrations. The regulation of contaminant bioavailability and transfer by changes in weather patterns and food web dynamics will be examined.

  9. Functional, biochemical, and histological biomarkers for immunocompetence in fish-eating birds of the Great Lakes

    SciTech Connect

    Grasman, K.A.; Scanlon, P.F.; Fox, G.A.

    1995-12-31

    The authors studied the effects of environmental contaminants on immune function and related biochemical and histological biomarkers in herring gulls (Larus argentatus) and Caspian terns (Sterna caspia) from the Great Lakes. An epidemiological analysis strongly supported the hypothesis that suppression of T-cell-mediated immunity was associated with high perinatal exposure to persistent organochlorines (primarily PCBs). Suppression of T cell function (measured by the phytohemagglutinin skin test) was most severe in colonies in Lake Ontario and Saginaw Bay for both species and in western Lake Erie (1992) for herring gulls. In herring gull chicks, the mass of the thymus decreased as liver EROD increased. Both species exhibited biologically significant differences among sites in anti-SRBC antibody titers, but there were few associations with organochlorines. In Caspian terns and, to a lesser degree, in herring gulls, plasma retinol decreased as organochlorines increased. In both species, plasma thyroxine concentrations differed significantly among sites, but there were no apparent associations with contaminants. Although thyroxine and retinol often are associated with immune function in laboratory studies, there were few consistent relationships between these variables and T-cell- and antibody-mediated immunity in this field study. These biochemical variables may be poor surrogate biomarkers for immune function in wild birds, although they are important indicators for other physiological systems. The histology of the thymus, bursa of Fabricius, and spleen were examined for developmental and functional abnormalities and the presence of infections.

  10. Organochlorine-induced immunosuppression in fish-eating birds of the Great Lakes

    SciTech Connect

    Grasman, K.A.; Scanlon, P.F.; Fox, G.A.

    1995-12-31

    This investigation studied the effects of environmental contaminants on immune function in fish-eating birds of the Great Lakes and evaluated the use of immunological tests as biomarkers for contaminant exposure in wild birds. During 1991--1994, specific immune functions and general hematological parameters were measured in herring gull (Larus argentatus) and Caspian tern (Stema caspia) chicks. Study sites were chosen across a wide range of organochlorine contamination caused primarily by PCBs. In herring gull adults, the heterophil to lymphocyte ratio decreased as liver EROD, an index of contaminant exposure, increased, In herring gull chicks, thymus mass decreased as EROD increased. At highly contaminated sites, gull and tern chicks showed a marked reduction in T cell-mediated immunity as measured by the phytohemagglutinin skin test. The thymic atrophy and T cell suppression were consistent with documented effects of PCBs in laboratory animals during development and growth. In both species, chicks exhibited biologically significant differences in antibody production among sites, but any relationships to contaminants or other factors remain unclear. In laboratory animals, PCBs exhibit variable effects on antibody production. Structural and functional parameters related to the immune system are useful biomarkers for assessing the effects of contaminants on wild birds.

  11. Waterbirds (other than Laridae) nesting in the middle section of Laguna Cuyutlán, Colima, México.

    PubMed

    Mellink, Eric; Riojas-López, Mónica E

    2008-03-01

    Laguna de Cuyutlán, in the state of Colima, Mexico, is the only large coastal wetland in a span of roughly 1150 km. Despite this, the study of its birds has been largely neglected. Between 2003 and 2006 we assessed the waterbirds nesting in the middle portion of Laguna Cuyutlán, a large tropical coastal lagoon, through field visits. We documented the nesting of 15 species of non-Laridae waterbirds: Neotropic Cormorant (Phalacrocorax brasilianus), Tricolored Egret (Egretta tricolor), Snowy Egret (Egretta thula), Little Blue Heron (Egretta caerulea), Great Egret (Ardea alba), Cattle Egret (Bubulcus ibis), Black-crowned Night-heron (Nycticorax nycticorax), Yellow-crowned Night-heron (Nyctanassa violacea), Green Heron (Butorides virescens), Roseate Spoonbill (Platalea ajaja), White Ibis (Eudocimus albus), Black-bellied Whistling-duck (Dendrocygna autumnalis), Clapper Rail (Rallus longirostris), Snowy Plover (Charadrius alexandrinus), and Black-necked Stilt (Himantopus mexicanus). These add to six species of Laridae known to nest in that area: Laughing Gulls (Larus atricilla), Royal Terns (Thalasseus maximus), Gull-billed Terns (Gelochelidon nilotica), Forster's Terns (S. forsteri), Least Terns (Sternula antillarum), and Black Skimmer (Rynchops niger), and to at least 57 species using it during the non-breeding season. With such bird assemblages, Laguna Cuyutlán is an important site for waterbirds, which should be given conservation status.

  12. Flap or soar? How a flight generalist responds to its aerial environment

    PubMed Central

    2016-01-01

    The aerial environment is heterogeneous in space and time and directly influences the costs of animal flight. Volant animals can reduce these costs by using different flight modes, each with their own benefits and constraints. However, the extent to which animals alter their flight modes in response to environmental conditions has rarely been studied in the wild. To provide insight into how a flight generalist can reduce the energetic cost of movement, we studied flight behaviour in relation to the aerial environmental and landscape using hundreds of hours of global positioning system and triaxial acceleration measurements of the lesser black-backed gull (Larus fuscus). Individuals differed largely in the time spent in flight, which increased linearly with the time spent in flight at sea. In general, flapping was used more frequently than more energetically efficient soaring flight. The probability of soaring increased with increasing boundary layer height and time closer to midday, reflecting improved convective conditions supportive of thermal soaring. Other forms of soaring flight were also used, including fine-scale use of orographic lift. We explore the energetic consequences of behavioural adaptations to the aerial environment and underlying landscape and implications for individual energy budgets, foraging ecology and reproductive success. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528785

  13. Chlamydiaceae in North Atlantic Seabirds Admitted to a Wildlife Rescue Center in Western France.

    PubMed

    Aaziz, R; Gourlay, P; Vorimore, F; Sachse, K; Siarkou, V I; Laroucau, K

    2015-07-01

    Birds are the primary hosts of Chlamydia psittaci, a bacterium that can cause avian chlamydiosis in birds and psittacosis in humans. Wild seabirds are frequently admitted to wildlife rescue centers (WRC) at European Atlantic coasts, for example, in connection with oil spills. To investigate the extent of chlamydial shedding by these birds and the resulting risk for animals in care and the medical staff, seabirds from a French WRC were sampled from May 2011 to January 2014. By use of a quantitative PCR (qPCR), 195 seabirds belonging to 4 orders, 5 families and 13 species were examined, of which 18.5% proved to be Chlamydiaceae positive. The highest prevalence of shedders was found in northern gannets (Morus bassanus) (41%), followed by European herring gulls (Larus argentatus) (14%) and common murres (Uria aalge) (7%). Molecular characterization and phylogenetic analysis of qPCR-positive northern gannet samples revealed two variants of a strain closely related to C. psittaci. In European herring gulls and in one common murre, strains showing high sequence similarity to the atypical Chlamydiaceae-like C122 previously found in gulls were detected. Our study shows that seabirds from the northeastern Atlantic Ocean carry several chlamydial organisms, including C. psittaci-related strains. The staff in WRCs should take protective measures, particularly in the case of mass admissions of seabirds. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Does garbage in diet improve Glaucous Gull reproductive output?

    USGS Publications Warehouse

    Powell, Abby N.; Weiser, Emily L.

    2010-01-01

    Anthropogenic subsidies are used by a variety of predators in areas developed for human use or residence. If subsidies promote population growth, these predators can have a negative effect on local prey species. The Glaucous Gull (Larus hyperboreus) is an abundant predator in northern Alaska that is believed to benefit from garbage as a supplemental food source, but this supposition has never been tested. In summer 2008 and 2009, we recorded the Glaucous Gull's diet and reproduction at 10 breeding colonies in northern Alaska. Colonies were in industrial, residential, and undeveloped areas and ranged from 5 to 75 km from the nearest landfill. By colony, garbage occurred in zero to 85% of pellets and food remains produced during the chick-rearing period, and the average number of chicks fledged per pair ranged from zero to 2.9. Random-forest analysis indicated that percent occurrence of garbage in the diet was the second most important factor (after number of eggs per pair) explaining variance in fledging rate. There was a significant positive correlation between percent occurrence of garbage in the diet and fledging rate in each year. If this correlation reflects a causal relationship, it suggests that human development that increases gulls' access to garbage could result in increased local gull populations. Such an increase could affect the gulls' natural prey species, including at least 14 species of shorebirds and waterfowl of conservation concern.

  15. Does garbage in the diet improve reproductive output of Glaucous Gulls

    USGS Publications Warehouse

    Weiser, E.L.; Powell, A.N.

    2010-01-01

    Anthropogenic subsidies are used by a variety of predators in areas developed for human use or residence. If subsidies promote population growth, these predators can have a negative effect on local prey species. The Glaucous Gull (Larus hyperboreus) is an abundant predator in northern Alaska that is believed to benefit from garbage as a supplemental food source, but this supposition has never been tested. In summer 2008 and 2009, we recorded the Glaucous Gull's diet and reproduction at 10 breeding colonies in northern Alaska. Colonies were in industrial, residential, and undeveloped areas and ranged from 5 to 75 km from the nearest landfill. By colony, garbage occurred in zero to 85% of pellets and food remains produced during the chick-rearing period, and the average number of chicks fledged per pair ranged from zero to 2.9. Random-forest analysis indicated that percent occurrence of garbage in the diet was the second most important factor (after number of eggs per pair) explaining variance in fledging rate. There was a significant positive correlation between percent occurrence of garbage in the diet and fledging rate in each year. If this correlation reflects a causal relationship, it suggests that human development that increases gulls' access to garbage could result in increased local gull populations. Such an increase could affect the gulls' natural prey species, including at least 14 species of shorebirds and waterfowl of conservation concern. ?? The Cooper Ornithological Society 2010.

  16. Distribution of marine birds on the mid- and North-Atlantic US outer continental shelf. Technical progress report, January 1978-July 1980

    SciTech Connect

    Powers, K.D.; Pittman, G.L.; Fitch, S.J.

    1980-09-01

    The species composition, distribution, and abundance of marine birds on continental shelf waters from Cape Hatteras to the Bay of Fundy were examined using ships-of-opportunity. Northern Fulmar, Cory's Shearwater, Greater Shearwater, Sooty Shearwater, Wilson's Storm-Petrel, Gannet, Red Phalarope, Great Black-backed Gull, Herring Gull, and Black-legged Kittiwake were the most abundant and common species. These species were ecologically dominant within the bird community in numbers and biomass. Georges Bank and Gulf of Marine regions generally had greatest estimates of standing stock and biomass; whereas, in the Middle Atlantic region these estimates were consistently lowest. Species diversity throughout the study area was greatest in spring and least in fall. Oceanic fronts at the continental shelf break and at Nantucket Shoals influenced the distribution of Wilson's Storm-Petrels and Red Phalaropes. Fishing activities were particularly important to Larus gull distribution. Fishes, squids, and crustaceans were the most important groups of prey items in diets of nine bird species. An oiled bird or pollution index was developed. According to the index, frequency of oiled birds was greatest in winter and spring, and gulls made up the majority of species with oiled plumages.

  17. The human influence on seabird nesting success: Conservation implications

    USGS Publications Warehouse

    Anderson, D.W.; Keith, J.O.

    1980-01-01

    Based on studies of brown pelicans Pelecanus occidentalis californicus and Heermann's gulls Larus heermanni, disturbances by recreationists, educational groups, local fishermen and scientists alike can be seriously disruptive and damaging to breeding seabirds in the Gulf of California and off the west coast of Baja California. Similar instances have been identified throughout the world?the problem is not difficult to document, but it is difficult to eliminate. The increasing human-seabird contacts on islands in the Gulf of California and along the west coast of Baja California raise serious questions and immediate concern about the continued preservation of nesting colonies of marine birds in those areas. Conservation measures must consider the extreme sensitivity of many seabirds to the inter- and intraspecific behavioural imbalances created by human disturbances. In some cases, total exclusion of humans may be required; in others, limited access might be possible under closely managed conditions at certain times of the year. A symbiotic relationship between seabird conservation, legitimate research and tourism should be the desired goal.

  18. Environmentally relevant concentrations of DE-71 and HBCD alter eggshell thickness and reproductive success of American kestrels.

    PubMed

    Fernie, Kim J; Shutt, J Laird; Letcher, Robert J; Ritchie, Ian J; Bird, David M

    2009-03-15

    Polybrominated diphenyl ethers (PBDEs) and total alpha-hexabromocyclododecane (HBCD) are flame-retardant additives that are commonly used in household and commercial applications. PBDE congeners, which are comprised of technical mixtures such as DE-71, are globally persistent and their concentrations are increasing in many species. Captive American kestrels (Falco sparverius) were exposed by diet to vehicle (safflower oil), or one of two environmentally relevant concentrations of DE-71 and unintentionally to HBCD. This exposure resulted in the birds laying eggs that contain PBDE and HBCD concentrations currently found in wild herring gull (Larus argentatus) and peregrine falcon (F. peregrinus) eggs, and compared to control kestrels, resulted in delayed egg laying and smaller eggs being laid, caused thinner eggshells and differential weight loss during embryonic development, and reduced fertility and reproductive success. The thickness of the eggshell declined as the concentrations of all measured PBDE and the total amount of a-HBCD congeners (except BDE-183 and BDE-209) increased; increasing concentrations of BDE-153, BDE-154, BDE-28, BDE-17, delayed egg laying, reduced eggshell mass (plus sigmaPBDEs), and reduced fledging success (BDE-153 and BDE-154 only). BDE-153 is the dominant congener recently found in peregrine eggs. The results of this study are consistent with the PBDE-associated brood reduction in wild European peregrines and may partially explain the decline of kestrels in North America.

  19. Migration And wintering areas Of Glaucous-winged Gulls From south-central Alaska

    USGS Publications Warehouse

    Hatch, Scott A.; Gill, V.A.; Mulcahy, Daniel M.

    2011-01-01

    We used satellite telemetry to investigate the migration patterns and wintering areas of Glaucous-winged Gulls (Larus glaucescens) from Middleton Island, Alaska, where this species' population increased tenfold from the 1970s to the 1990s. Fall migration spanned 11 weeks, including numerous stopovers en route, apparently for feeding. Spring migration from wintering sites to Middleton Island was shorter (4 weeks) and more direct. One juvenile spent several months in southern Prince William Sound. An adult spent several months near Craig, southeast Alaska, while three others overwintered in southern British Columbia. For all four wintering adults use of refuse-disposal sites was evident or strongly suggested. Commensalism with humans may have contributed to the increase on Middleton, but a strong case can also be made for a competing explanation-regional recruitment of gulls to high-quality nesting habitat in Alaska created after the earthquake of 1964. An analysis of band returns reveals broad overlap in the wintering grounds of gulls from different Alaska colonies and of gulls banded on the west coast from British Columbia to California. The seasonal movement of many gulls from Alaska is decidedly migratory, whereas gulls from British Columbia, Washington, and Oregon disperse locally in winter.

  20. Migration and wintering areas of glaucous-winged Gulls from south-central Alaska

    USGS Publications Warehouse

    Hatch, Shyla A.; Gill, V.A.; Mulcahy, D.M.

    2011-01-01

    We used satellite telemetry to investigate the migration patterns and wintering areas of Glaucouswinged Gulls (Larus glaucescens) from Middleton Island, Alaska, where this species' population increased tenfold from the 1970s to the 1990s. Fall migration spanned 11 weeks, including numerous stopovers en route, apparently for feeding. Spring migration from wintering sites to Middleton Island was shorter (4 weeks) and more direct. One juvenile spent several months in southern Prince William Sound. An adult spent several months near Craig, southeast Alaska, while three others overwintered in southern British Columbia. For all four wintering adults use of refuse-disposal sites was evident or strongly suggested. Commensalism with humans may have contributed to the increase on Middleton, but a strong case can also be made for a competing explanation-regional recruitment of gulls to high-quality nesting habitat in Alaska created after the earthquake of 1964. An analysis of band returns reveals broad overlap in the wintering grounds of gulls from different Alaska colonies and of gulls banded on the west coast from British Columbia to California. The seasonal movement of many gulls from Alaska is decidedly migratory, whereas gulls from British Columbia, Washington, and Oregon disperse locally in winter. ?? The Cooper Ornithological Society 2011.

  1. Feathered Detectives: Real-Time GPS Tracking of Scavenging Gulls Pinpoints Illegal Waste Dumping

    PubMed Central

    Grémillet, David; Afán, Isabel; Ramírez, Francisco; Bouten, Willem; Forero, Manuela G.

    2016-01-01

    Urban waste impacts human and environmental health, and waste management has become one of the major challenges of humanity. Concurrently with new directives due to manage this human by-product, illegal dumping has become one of the most lucrative activities of organized crime. Beyond economic fraud, illegal waste disposal strongly enhances uncontrolled dissemination of human pathogens, pollutants and invasive species. Here, we demonstrate the potential of novel real-time GPS tracking of scavenging species to detect environmental crime. Specifically, we were able to detect illegal activities at an officially closed dump, which was visited recurrently by 5 of 19 GPS-tracked yellow-legged gulls (Larus michahellis). In comparison with conventional land-based surveys, GPS tracking allows a much wider and cost-efficient spatiotemporal coverage, even of the most hazardous sites, while GPS data accessibility through the internet enables rapid intervention. Our results suggest that multi-species guilds of feathered detectives equipped with GPS and cameras could help fight illegal dumping at continental scales. We encourage further experimental studies, to infer waste detection thresholds in gulls and other scavenging species exploiting human waste dumps. PMID:27448048

  2. 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.

  3. Selenium and metal concentrations in waterbird eggs and chicks at Agassiz National Wildlife Refuge, Minnesota

    USGS Publications Warehouse

    Custer, T.W.; Custer, Christine M.; Eichhorst, B.A.; Warburton, D.

    2007-01-01

    Exceptionally high cadmium (Cd) and chromium (Cr) concentrations were reported in eggs, feathers, or livers of selected waterbird species nesting at Agassiz National Wildlife Refuge (Agassiz) in 1994. Ten- to 15-day-old Franklin's gull (Larus pipixcan), black-crowned night-heron (Nycticorax nycticorax), and eared grebe (Podiceps nigricollis) chicks were collected in 1998, 1999, and 2001 at Agassiz and analyzed for selenium (Se) and metals including Cd and Cr. Freshly laid eggs were collected in 2001 from Franklin's gull, black-crowned night-heron, eared grebe, and pied-billed grebe (Podilymbus podiceps) nests at Agassiz. Based on a multivariate analysis, the pattern of Se and metal concentrations differed among species for eggs, chick feathers, and chick livers. Low Cd and Cr concentrations were measured in eggs, chick livers, and chick feathers of all four species. Mercury concentrations in black-crowned night-heron and eared grebe eggs collected from Agassiz in 2001 were lower than concentrations reported in 1994. Se and metal concentrations, including Cd and Cr, in waterbird eggs and chicks collected at Agassiz in 1998, 1999, and 2001 were not at toxic levels. ?? 2007 Springer Science+Business Media, LLC.

  4. Parathion poisoning of Mississippi kites in Oklahoma

    USGS Publications Warehouse

    Franson, J. Christian

    1994-01-01

    Parathion(phosphorothioic acid O, O-diethyl O-[4-nitrophenyl] ester) is a broad spectrum organophosphorus insecticide, used on a variety of crops and occasionally for mosquito control, and is highly toxic to birds (Smith 1987). Intentional poisoning with parathion is reported to have killed more than 8000 red-winged blackbirds (Agelaius phoeniceus), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater) and European starlings (Sturnus vulgaris) in two separate instances (Stone et al. 1984). Use of parathion on wheat fields has resulted in the mortality of about 1600 Canada geese (Branta canadensis) and other waterfowl in one instance (White et al. 1982) and about 200 Canada geese in another (Flickinger et al. 1991). More than 200 laughing gulls (Larus atricilla) died near cotton fields treated with parathion (White et al. 1979). Secondary poisoning of raptors resulting from the consumption of prey exposed to parathion, has been reported experimentally and in the field. Stone et al. (1984) found two dead red-tailed hawks (Buteo jamaicensis), a Cooper's hawk (Accipiter cooperii) and an American kestrel (Falco sparverius) that had fed on blackbirds killed by parathion. One of four American kestrels died after being fed cricket frogs (Acris crepitans) that had been exposed to 10ppm parathion for 96 hr (Fleming et al. 1982). The Mississippi kite (Ictinia mississippensis) is highly insectivorous (Brown and Amadon 1968) and is thus subject to secondary poisoning resulting from consumption of insects exposed to pesticides. I report here an instance of secondary parathion poisoning in wild Mississippi kites.

  5. Sexing California gulls using morphometrics and discriminant function analysis

    USGS Publications Warehouse

    Herring, Garth; Ackerman, Joshua T.; Eagles-Smith, Collin A.; Takekawa, John Y.

    2010-01-01

    A discriminant function analysis (DFA) model was developed with DNA sex verification so that external morphology could be used to sex 203 adult California Gulls (Larus californicus) in San Francisco Bay (SFB). The best model was 97% accurate and included head-to-bill length, culmen depth at the gonys, and wing length. Using an iterative process, the model was simplified to a single measurement (head-to-bill length) that still assigned sex correctly 94% of the time. A previous California Gull sex determination model developed for a population in Wyoming was then assessed by fitting SFB California Gull measurement data to the Wyoming model; this new model failed to converge on the same measurements as those originally used by the Wyoming model. Results from the SFB discriminant function model were compared to the Wyoming model results (by using SFB data with the Wyoming model); the SFB model was 7% more accurate for SFB California gulls. The simplified DFA model (head-to-bill length only) provided highly accurate results (94%) and minimized the measurements and time required to accurately sex California Gulls.

  6. Skin pentosidine and telomere length do not covary with age in a long-lived seabird.

    PubMed

    Rattiste, Kalev; Klandorf, Hillar; Urvik, Janek; Sepp, Tuul; Asghar, Muhammad; Hasselquist, Dennis; Cooey, Crissa; Hõrak, Peeter

    2015-08-01

    The questions about why and how senescence occurs in the wild are among the most pertinent ones in evolutionary ecology. Telomere length is a commonly used marker for aging, while other biomarkers of aging have received considerably less attention. Here we studied how another potent indicator of aging-skin pentosidine concentration-relates to age and blood telomere length in a long-lived seabird with well-documented reproductive senescence. We found no associations between telomere length, skin pentosidine and chronological age in male common gulls (Larus canus), aging from 2 to 30 years. However, the variance in telomere length was 4.6 times higher among the birds older than 13 years, which hints at relaxed selection on telomere length among the birds that have passed their prime age of reproduction. These results suggest that physiological and chronological ages may be largely uncoupled in our study system. Furthermore, our findings do not support a hypothesis about the presence of a common physiological factor (e.g., such as oxidative stress) that would cause covariation between two independent markers of aging.

  7. A pelagic outbreak of avian cholera in North American gulls: Scavenging as a primary mechanism for transmission?

    USGS Publications Warehouse

    Wille, Michelle; McBurney, Scott; Robertson, Gregory J.; Wilhelm, Sabine; Blehert, David; Soos, Catherine; Dunphy, Ron; Whitney, Hugh

    2016-01-01

    Avian cholera, caused by the bacterium Pasteurella multocida, is an endemic disease globally, often causing annual epizootics in North American wild bird populations with thousands of mortalities. From December 2006 to March 2007, an avian cholera outbreak caused mortality in marine birds off the coast of Atlantic Canada, largely centered 300–400 km off the coast of the island of Newfoundland. Scavenging gulls (Larus spp.) were the primary species detected; however, mortality was also identified in Black-legged Kittiwakes (Rissa tridactyla) and one Common Raven (Corvus corax), a nonmarine species. The most common gross necropsy findings in the birds with confirmed avian cholera were acute fibrinous and necrotizing lesions affecting the spleen, air sacs, and pericardium, and nonspecific hepatomegaly and splenomegaly. The etiologic agent, P. multocida serotype 1, was recovered from 77 of 136 carcasses examined, and confirmed or probable avian cholera was diagnosed in 85 cases. Mortality observed in scavenging gull species was disproportionately high relative to their abundance, particularly when compared to nonscavenging species. The presence of feather shafts in the ventricular lumen of the majority of larid carcasses diagnosed with avian cholera suggests scavenging of birds that died from avian cholera as a major mode of transmission. This documentation of an outbreak of avian cholera in a North American pelagic environment affecting primarily scavenging gulls indicates that offshore marine environments may be a component of avian cholera dynamics.

  8. Poplar Island Environmental Restoration Project: Challenges in waterbird restoration on an island in Chesapeake Bay

    USGS Publications Warehouse

    Erwin, R.M.; Miller, J.; Reese, J.G.

    2007-01-01

    At 460 hectares, the Paul Sarbanes Environmental Restoration Project at Poplar Island, Talbot County, Maryland, represents the largest 'beneficial use' dredged material project of the U. S. Army Corps of Engineers (a cooperative project with Maryland Port Administration). Begun in 1998, the 15-year restoration project will ultimately consist of roughly 220 ha of uplands and 220 ha of tidal wetland habitats, with limited areas of dike roads, perimeter riprap, and unvegetated mudflats. Wetland restoration began in one small section (or 'cell') in 2002, but not all cells will be filled with dredged material until at least 2013. As a major objective of the restoration, six species of waterbirds were identified as 'priority species' for Chesapeake Bay: American black duck (Anas rubripes), snowy egret (Egretta thula), cattle egret (Bubulcus ibis), osprey (Pandion haliaetus), common tern (Sterna hirundo), and least tern (S. antillarum). Monitoring of nesting activities of these species from 2002 to 2005 indicated that all species except black ducks colonized the site rapidly. More than 800 pairs of common terns nested in 2003 to 2004. Because of predation by red fox (Vulpes vulpes) and great horned owl (Bubo virginianus), reproductive success was very low for the terns. Trapping was effective in removing the foxes, and other controls have been applied to opportunistic nesting species including herring gulls (Larus argentatus) and Canada geese (Branta canadensis). An effective public education program on the island has helped address concerns about animal control.

  9. Prevalence of blood parasites in Japanese wild birds.

    PubMed

    Murata, Koichi

    2002-09-01

    The prevalence of blood parasites was investigated in 701 Japanese wild birds for 13 years from January, 1988 to March, 2001. Most of the injured or sick birds were caught in the suburbs of Kobe City, Hyogo Prefecture and brought to the zoo for clinical care. Among all the birds examined, 10.6% were infected with hematozoa belonging to three genera as Plasmodium (1.7% of the samples), Haemoproteus (5.1% of the samples) and Leucocytozoon (4.6% of the samples), and two birds (0.29% of the samples), a Japanese grosbeak (Coccothraustes personatus) and a dusky thrush (Turdus naumanni), were infected with microfilariae. Mixed infection with Leucocytozoon sp. and Haemoproteus sp. was observed in 6 individuals of 4 species and that with Leucocytozoon sp. and microfilariae was observed in 2 individuals of 2 species of bird. Relatively high positive rates were 75%(3/4) in the scops owl (Otus scops), 71.4% (10/14) in the ural owl (Strix uralensis), 57.7% (15/26) in the jungle crow (Corvus macrorhynchos), 57.1% (4/7) in the black-tailed gull (Larus crassirostris), 55.6% (5/9) in the brown hawk owl (Ninox scutulata), 41% (16/39) in the carrion crow (Corvus corone) and 24.1% (7/29) in the night heron (Nycticorax nicticorax).

  10. Miniaturization of a transthyretin binding assay using a fluorescent probe for high throughput screening of thyroid hormone disruption in environmental samples.

    PubMed

    Ouyang, Xiyu; Froment, Jean; Leonards, Pim E G; Christensen, Guttorm; Tollefsen, Knut-Erik; de Boer, Jacob; Thomas, Kevin V; Lamoree, Marja H

    2017-03-01

    Thyroid hormone (TH) disrupting compounds are potentially important environmental contaminants due to their possible adverse neurological and developmental effects on both humans and wildlife. Currently, the most successful bio-analytical method to detect and evaluate TH disruptors, which target the plasma transport of TH in environmental samples, is the radio-ligand thyroxine-transthyretin (T4-TTR) binding assay. Yet, costly materials and tedious handling procedures prevent the use of this assay in high throughput analysis that is nowadays urgently demanded in environmental quality assessment. For the first time a miniaturized fluorescence T4-TTR binding assay was developed in a 96 well microplate and tested with eight TH disrupting compounds. For most of the compounds, the sensitivity of the newly developed assay was slightly lower than the radio-ligand binding assay, however, throughput was enhanced at least 100-fold, while using much cheaper materials. The TH disrupting potency of 22 herring gull (Larus argentatus) egg extracts, collected from two different locations (Musvær and Reiaren) in Norway, was evaluated to demonstrate the applicability of the assay for environmental samples. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. The influence of trophic level and feeding location of the levels of organochlorine contaminants in seabird eggs as revealed by stable carbon and nitrogen isotope analysis

    SciTech Connect

    Hobson, K.; Jarman, W.M.; Bott, J.A.; Bacon, C.E.; Sydeman, W.

    1994-12-31

    Seabird eggs have been used extensively to assay contaminants in marine food webs, but links to trophic level or feeding location have remained poorly understood due to limitations inherent in conventional dietary studies. Stable-isotope analysis of bird eggs may be used to infer trophic position and feeding location of adult seabirds and can be readily correlated with measurements of egg contaminant levels. The authors measured stable-carbon ({delta}{sup 13}C) and nitrogen ({delta}{sup 15}N) isotope abundance, and organochlorine contaminants (DDTs, PCBs, chlordanes, etc.) in eggs from Cassin`s Auklet (Ptychoramphus aleutica), Common Murre (Uria aalge), Pigeon Guillemot (Cepphus columba). Rhinoceros Auklet (Cerorhinca monocerata), Pelagic Cormorant (Phalacrocorax pelagicus), Brandt`s Cormorant (Phalacrocorax penicillatus), and Western Gull (Larus) from Southeast Farallon Island together with rockfish (Sebastes spp.), anchovy (Engraulis spp.), and euphausiid prey from the Gulf of the Farallones. Consistent with its planktivorous diet and pelagic feeding habits, Cassin`s Auklet showed the lowest mean {delta}{sup 15}N value and the least enriched {delta}{sup 13}C values. Measures of trophic level and foraging location were constructed for all other seabirds relative to these isotopic endpoints. Contaminant levels in the eggs and fish will be interpreted in light of the stable-isotope results.

  12. Submarine landslides in the Santa Barbara Channel as potential tsunami sources

    USGS Publications Warehouse

    Greene, H. Gary; Murai, L.Y.; Watts, P.; Maher, N.A.; Fisher, M.A.; Paull, C.E.; Eichhubl, P.

    2006-01-01

    Recent investigations using the Monterey Bay Aquarium Research Institutes (MBARI) Remotely Operated Vehicles (ROVs) "Ventana" and "Tiburon" and interpretation of MBARI's EM 300 30 kHz multibeam bathymetric data show that the northern flank of the Santa Barbara Basin has experienced massive slope failures. Of particular concern is the large (130 km2) Goleta landslide complex located off Coal Oil Point near the town of Goleta, that measures 14.6-km long extending from a depth of 90 m to nearly 574 m deep and is 10.5 km wide. We estimate that approximately 1.75 km3 has been displaced by this slide during the Holocene. This feature is a complex compound submarine landslide that contains both surfical slump blocks and mud flows in three distinct segments. Each segment is composed of a distinct head scarp, down-dropped head block and a slide debris lobe. The debris lobes exhibit hummocky topography in the central areas that appear to result from compression during down slope movement. The toes of the western and eastern lobes are well defined in the multibeam image, whereas the toe of the central lobe is less distinct. Continuous seismic reflection profiles show that many buried slide debris lobes exist and comparison of the deformed reflectors with ODP Drill Site 149, Hole 893 suggest that at least 200 000 years of failure have occurred in the area (Fisher et al., 2005a). Based on our interpretation of the multibeam bathymetry and seismic reflection profiles we modeled the potential tsunami that may have been produced from one of the three surfical lobes of the Goleta slide. This model shows that a 10 m high wave could have run ashore along the cliffs of the Goleta shoreline. Several other smaller (2 km2 and 4 km2) slides are located on the northern flank of the Santa Barbara Basin, both to the west and east of Goleta slide and on the Concepcion fan along the western flank of the basin. One slide, named the Gaviota slide, is 3.8 km2, 2.6 km long and 1.7 km wide. A

  13. Submarine landslides in the Santa Barbara Channel as potential tsunami sources

    NASA Astrophysics Data System (ADS)

    Greene, H. G.; Murai, L. Y.; Watts, P.; Maher, N. A.; Fisher, M. A.; Paull, C. E.; Eichhubl, P.

    2006-01-01

    Recent investigations using the Monterey Bay Aquarium Research Institutes (MBARI) Remotely Operated Vehicles (ROVs) "Ventana" and "Tiburon" and interpretation of MBARI's EM 300 30 kHz multibeam bathymetric data show that the northern flank of the Santa Barbara Basin has experienced massive slope failures. Of particular concern is the large (130 km2) Goleta landslide complex located off Coal Oil Point near the town of Goleta, that measures 14.6-km long extending from a depth of 90 m to nearly 574 m deep and is 10.5 km wide. We estimate that approximately 1.75 km3 has been displaced by this slide during the Holocene. This feature is a complex compound submarine landslide that contains both surfical slump blocks and mud flows in three distinct segments. Each segment is composed of a distinct head scarp, down-dropped head block and a slide debris lobe. The debris lobes exhibit hummocky topography in the central areas that appear to result from compression during down slope movement. The toes of the western and eastern lobes are well defined in the multibeam image, whereas the toe of the central lobe is less distinct. Continuous seismic reflection profiles show that many buried slide debris lobes exist and comparison of the deformed reflectors with ODP Drill Site 149, Hole 893 suggest that at least 200 000 years of failure have occurred in the area (Fisher et al., 2005a). Based on our interpretation of the multibeam bathymetry and seismic reflection profiles we modeled the potential tsunami that may have been produced from one of the three surfical lobes of the Goleta slide. This model shows that a 10 m high wave could have run ashore along the cliffs of the Goleta shoreline. Several other smaller (2 km2 and 4 km2) slides are located on the northern flank of the Santa Barbara Basin, both to the west and east of Goleta slide and on the Conception fan along the western flank of the basin. One slide, named the Gaviota slide, is 3.8 km2, 2.6 km long and 1.7 km wide. A

  14. Species differences in the sensitivity of avian embryos to methylmercury

    USGS Publications Warehouse

    Heinz, G.H.; Hoffman, D.J.; Klimstra, J.D.; Stebbins, K.R.; Kondrad, S.L.; Erwin, C.A.

    2009-01-01

    We injected doses of methylmercury into the air cells of eggs of 26 species of birds and examined the dose-response curves of embryo survival. For 23 species we had adequate data to calculate the median lethal concentration (LC50). Based on the dose-response curves and LC50s, we ranked species according to their sensitivity to injected methylmercury. Although the previously published embryotoxic threshold of mercury in game farm mallards (Anas platyrhynchos) has been used as a default value to protect wild species of birds, we found that, relative to other species, mallard embryos are not very sensitive to injected methylmercury; their LC50 was 1.79 ug/g mercury on a wet-weight basis. Other species we categorized as also exhibiting relatively low sensitivity to injected methylmercury (their LC50s were 1 ug/g mercury or higher) were the hooded merganser (Lophodytes cucullatus), lesser scaup (Aythya affinis), Canada goose (Branta canadensis), double-crested cormorant (Phalacrocorax auritus), and laughing gull (Larus atricilla). Species we categorized as having medium sensitivity (their LC50s were greater than 0.25 ug/g mercury but less than 1 ug/g mercury) were the clapper rail (Rallus longirostris), sandhill crane (Grus canadensis), ring-necked pheasant (Phasianus colchicus), chicken (Gallus gallus), common grackle (Quiscalus quiscula), tree swallow (Tachycineta bicolor), herring gull (Larus argentatus), common tern (S terna hirundo), royal tern (Sterna maxima), Caspian tern (Sterna caspia), great egret (Ardea alba), brown pelican (Pelecanus occidentalis), and anhinga (Anhinga anhinga). Species we categorized as exhibiting high sensitivity (their LC50s were less than 0.25 ug/g mercury) were the American kestrel (Falco sparverius), osprey (Pandion haliaetus), white ibis (Eudocimus albus), snowy egret (Egretta thula), and tri-colored heron (Egretta tricolor). For mallards, chickens, and ring-necked pheasants (all species for which we could compare the toxicity of our

  15. Species differences in the sensitivity of avian embryos to methylmercury.

    PubMed

    Heinz, Gary H; Hoffman, David J; Klimstra, Jon D; Stebbins, Katherine R; Kondrad, Shannon L; Erwin, Carol A

    2009-01-01

    We injected doses of methylmercury into the air cells of eggs of 26 species of birds and examined the dose-response curves of embryo survival. For 23 species we had adequate data to calculate the median lethal concentration (LC(50)). Based on the dose-response curves and LC(50)s, we ranked species according to their sensitivity to injected methylmercury. Although the previously published embryotoxic threshold of mercury in game farm mallards (Anas platyrhynchos) has been used as a default value to protect wild species of birds, we found that, relative to other species, mallard embryos are not very sensitive to injected methylmercury; their LC(50 )was 1.79 microg/g mercury on a wet-weight basis. Other species we categorized as also exhibiting relatively low sensitivity to injected methylmercury (their LC(50)s were 1 microg/g mercury or higher) were the hooded merganser (Lophodytes cucullatus), lesser scaup (Aythya affinis), Canada goose (Branta canadensis), double-crested cormorant (Phalacrocorax auritus), and laughing gull (Larus atricilla). Species we categorized as having medium sensitivity (their LC(50)s were greater than 0.25 microg/g mercury but less than 1 microg/g mercury) were the clapper rail (Rallus longirostris), sandhill crane (Grus canadensis), ring-necked pheasant (Phasianus colchicus), chicken (Gallus gallus), common grackle (Quiscalus quiscula), tree swallow (Tachycineta bicolor), herring gull (Larus argentatus), common tern (Sterna hirundo), royal tern (Sterna maxima), Caspian tern (Sterna caspia), great egret (Ardea alba), brown pelican (Pelecanus occidentalis), and anhinga (Anhinga anhinga). Species we categorized as exhibiting high sensitivity (their LC(50)s were less than 0.25 microg/g mercury) were the American kestrel (Falco sparverius), osprey (Pandion haliaetus), white ibis (Eudocimus albus), snowy egret (Egretta thula), and tri-colored heron (Egretta tricolor). For mallards, chickens, and ring-necked pheasants (all species for which we

  16. Introgressive hybridization and the evolutionary history of the herring gull complex revealed by mitochondrial and nuclear DNA

    PubMed Central

    2010-01-01

    Background Based on extensive mitochondrial DNA (mtDNA) sequence data, we previously showed that the model of speciation among species of herring gull (Larus argentatus) complex was not that of a ring species, but most likely due more complex speciation scenario's. We also found that two species, herring gull and glaucous gull (L. hyperboreus) displayed an unexpected biphyletic distribution of their mtDNA haplotypes. It was evident that mtDNA sequence data alone were far from sufficient to obtain a more accurate and detailed insight into the demographic processes that underlie speciation of this complex, and that extensive autosomal genetic analysis was warranted. Results For this reason, the present study focuses on the reconstruction of the phylogeographic history of a limited number of gull species by means of a combined approach of mtDNA sequence data and 230 autosomal amplified fragment length polymorphism (AFLP) loci. At the species level, the mtDNA and AFLP genetic data were largely congruent. Not only for argentatus and hyperboreus, but also among a third species, great black-backed gull (L. marinus) we observed two distinct groups of mtDNA sequence haplotypes. Based on the AFLP data we were also able to detect distinct genetic subgroups among the various argentatus, hyperboreus, and marinus populations, supporting our initial hypothesis that complex demographic scenario's underlie speciation in the herring gull complex. Conclusions We present evidence that for each of these three biphyletic gull species, extensive mtDNA introgression could have taken place among the various geographically distinct subpopulations, or even among current species. Moreover, based on a large number of autosomal AFLP loci, we found evidence for distinct and complex demographic scenario's for each of the three species we studied. A more refined insight into the exact phylogeographic history within the herring gull complex is still impossible, and requires detailed autosomal

  17. Evaluating gull diets: A comparison of conventional methods and stable isotope analysis

    USGS Publications Warehouse

    Weiser, E.L.; Powell, A.N.

    2011-01-01

    Samples such as regurgitated pellets and food remains have traditionally been used in studies of bird diets, but these can produce biased estimates depending on the digestibility of different foods. Stable isotope analysis has been developed as a method for assessing bird diets that is not biased by digestibility. These two methods may provide complementary or conflicting information on diets of birds, but are rarely compared directly. We analyzed carbon and nitrogen stable isotope ratios of feathers of Glaucous Gull (Larus hyperboreus) chicks from eight breeding colonies in northern Alaska, and used a Bayesian mixing model to generate a probability distribution for the contribution of each food group to diets. We compared these model results with probability distributions from conventional diet samples (pellets and food remains) from the same colonies and time periods. Relative to the stable isotope estimates, conventional analysis often overestimated the contributions of birds and small mammals to gull diets and often underestimated the contributions of fish and zooplankton. Both methods gave similar estimates for the contributions of scavenged caribou, miscellaneous marine foods, and garbage to diets. Pellets and food remains therefore may be useful for assessing the importance of garbage relative to certain other foods in diets of gulls and similar birds, but are clearly inappropriate for estimating the potential impact of gulls on birds, small mammals, or fish. However, conventional samples provide more species-level information than stable isotope analysis, so a combined approach would be most useful for diet analysis and assessing a predator's impact on particular prey groups. ?? 2011 Association of Field Ornithologists.

  18. A nonlethal microsampling technique to monitor the effects of mercury on wild bird eggs

    USGS Publications Warehouse

    Stebbins, Katherine R.; Klimstra, Jon D.; ,; Ackerman, Joshua T.; Heinz, Gary

    2009-01-01

    Methylmercury is the predominant chemical form of mercury reported in the eggs of wild birds, and the embryo is the most sensitive life stage to methylmercury toxicity. Protective guidelines have been based mainly on captive-breeding studies with chickens (Gallus gallus), mallards (Anas platyrhynchos), and ring-necked pheasants (Phasianus colchicus) or on field studies where whole eggs were collected and analyzed and the effects of the mercury were measured based on the reproductive success of the remaining eggs. However, both of these methods have limitations. As an alternative, we developed a technique that involves extracting a small sample of albumen from a live egg, sealing the egg, returning the egg to its nest to be naturally incubated by the parents, and then relating the hatching success of this microsampled egg to its mercury concentration. After first developing this technique in the laboratory using chicken and mallard eggs, we selected the laughing gull (Larus atricilla) and black-necked stilt (Himantopus mexicanus) as test subjects in the field. We found that 92% of the microsampled laughing gull eggs met our reproductive endpoint of survival to the beginning of hatching compared to 100% for the paired control eggs within the same nests. Microsampled black-necked stilt eggs exhibited 100% hatching success compared to 93% for the paired control eggs. Our results indicate that microsampling is an effective tool for nonlethally sampling mercury concentrations in eggs and, as such, can be used for monitoring sensitive species, as well as for improving studies that examine the effects of mercury on avian reproduction.

  19. Premature feather loss among common tern chicks in Ontario: the return of an enigmatic developmental anomaly.

    PubMed

    Arnold, Jennifer M; Tyerman, Donald J; Crump, Doug; Williams, Kim L; Oswald, Stephen A

    2016-01-01

    In July 2014, we observed premature feather loss (PFL) among non-sibling, common tern Sterna hirundo chicks between two and four weeks of age at Gull Island in northern Lake Ontario, Canada. Rarely observed in wild birds, to our knowledge PFL has not been recorded in terns since 1974, despite the subsequent banding of hundreds of thousands of tern chicks across North America alone. The prevalence, 5% of chicks (9/167), and extent of feather loss we report is more extreme than in previous reports for common terns but was not accompanied by other aberrant developmental or physical deformities. Complete feather loss from all body areas (wing, tail, head and body) occurred over a period of a few days but all affected chicks appeared vigorous and quickly began to grow replacement feathers. All but one chick (recovered dead and submitted for post-mortem) most likely fledged 10-20 days after normal fledging age. We found no evidence of feather dystrophy or concurrent developmental abnormalities unusual among affected chicks. Thus, the PFL we observed among common terns in 2014 was largely of unknown origin. There was striking temporal association between the onset of PFL and persistent strong southwesterly winds that caused extensive mixing of near-shore surface water with cool, deep lake waters. One hypothesis is that PFL may have been caused by unidentified pathogens or toxins welling up from these deep waters along the shoreline but current data are insufficient to test this. PFL was not observed among common terns at Gull Island in 2015, although we did observe similar feather loss in a herring gull Larus argentatus chick in that year. Comparison with sporadic records of PFL in other seabirds suggests that PFL may be a rare, but non-specific, response to a range of potential stressors. PFL is now known for gulls, penguins and terns.

  20. Antibiotic-Resistant Escherichia coli Bacteria, Including Strains with Genes Encoding the Extended-Spectrum Beta-Lactamase and QnrS, in Waterbirds on the Baltic Sea Coast of Poland▿

    PubMed Central

    Literak, Ivan; Dolejska, Monika; Janoszowska, Dagmar; Hrusakova, Jolana; Meissner, Wlodzimierz; Rzyska, Hanna; Bzoma, Szymon; Cizek, Alois

    2010-01-01

    Individual cloacal swabs of mallards (Anas platyrhynchos) and of herring gulls (Larus argentatus), as well as samples of waterbird feces obtained in 2008 and 2009, were cultivated for Escherichia coli. Isolates of E. coli were tested for susceptibilities to 12 antimicrobial agents by the disk diffusion method. Moreover, the samples were subcultivated on MacConkey agar (MCA) containing cefotaxime (2 mg liter−1) to detect E. coli with extended-spectrum beta-lactamase (ESBL) and subsequently on MCA supplemented with ciprofloxacin (0.05 mg liter−1) and MCA with nalidixic acid (20 mg liter−1) to isolate fluoroquinolone-resistant E. coli. PCR was used to detect specific antibiotic resistance genes. We found 9 E. coli isolates producing ESBL with bla genes: blaCTX-M-1 (6 isolates), blaCTX-M-9 plus blaTEM-1b (1 isolate), blaCTX-M-15 plus blaOXA-1 (1 isolate), and blaSHV-12 (1 isolate). In the isolate with blaCTX-M-15, the gene aac(6)-Ib-cr was also detected. The bla genes were harbored by transferable plasmids of the IncN and IncI1 groups. Nine quinolone-resistant E. coli isolates with qnrS genes were found and characterized. The gene qnrS was associated with a Tn3-like transposon on the IncX1 plasmid together with blaTEM-1 in two isolates. The gene qnrS was also harbored by conjugative plasmids of the IncN and IncX2 groups. Even if populations of wild birds are not directly influenced by antibiotic practice, we have demonstrated that antibiotic-resistant E. coli strains, including strains with various ESBL and qnrS genes, are found in the feces of wild birds on the coast of the Baltic Sea in Poland. PMID:20952638

  1. Climate change, reproductive performance and diet composition of marine birds in the southern California Current system, 1969 1997

    NASA Astrophysics Data System (ADS)

    Sydeman, William J.; Hester, Michelle M.; Thayer, Julie A.; Gress, Franklin; Martin, Paige; Buffa, Joelle

    We studied the effects of low-frequency climate change on the reproductive performance of 11 species of marine bird in the southern California Current system, 1969-1997. Reproductive performance of Brown Pelican ( Pelecanus occidentalis) and Double-crested Cormorant ( Phalacrocrax auritus) in southern California demonstrated an increase in the 1970s and early 1980s, attributable to recovery from organochlorine contamination (primarily DDE). Brandt's Cormorant ( Phalacrocorax penicillatus) in central California was the only species to demonstrate a secular increase in performance through time, a pattern that remains unexplained. Ashy Storm-petrel ( Oceanodroma homochroa) and Pelagic Cormorant ( Phalacrocorax pelagicus) demonstrated curvilinear patterns of change, with decreasing reproductive performance in the past decade. All other species including Western Gull ( Larus occidentalis), Pigeon Guillemot ( Cepphus columba), Xantus's Murrelet ( Synthiloboramphus hypoleucus), Common Murre ( Uria aalge), Cassin's Auklet ( Ptychoramphus aleuticus) and Rhinoceros Auklet ( Cerorhinca monocerata) showed diminishing reproductive performance through time. Patterns of change for the murre and auklets were not significant, presumably because of a lack of reproductive variation for these species, which display a conservative breeding effort (i.e. single-egg clutches). Changes in the birds' abilities to provision young and maintain chick survival during May-July each year appeared most closely related to overall changes in reproductive performance. Dietary change indicated a decline in use of juvenile rockfish ( Sebastes spp.) by marine birds in central California. There was also significant interannual variability in consumption of juvenile rockfish and the euphausiid Thysanoessa spinifera. Patterns of change in marine bird reproductive performance were generally concordant between southern and central California after considering the period of recovery for Brown Pelican and

  2. Species density of waterbirds in offshore habitats in western Lake Erie

    USGS Publications Warehouse

    Stapanian, M.A.; Waite, Thomas A.

    2003-01-01

    Offshore censuses of birds are lacking for inland seas, such as the Laurentian Great Lakes, but may provide valuable information for managing species that are in conflict with human interests. Birds were counted along 31 established transects in four habitats in western Lake Erie: offshore of waterbird refuges, offshore of beaches with human development, on reefs and shoals, and in open water. A total of 161 10-min counts were conducted between 24 April and 1 September 2000. The mean number of aquatic bird species/kmA? (species density) was greater offshore of refuges than on open water. For all habitats combined, species density increased over time. This was mainly due to the arrival of Bonaparte's Gulls (Larus philadelphia) and Great Black-backed Gulls (L. marinus), two fall and winter residents that do not breed in the study area, and increased use of open water and reefs and shoals by Herring Gulls (L argentatus) and Ring-billed Gulls (L delawarensis) after the nesting season. Species density was not strongly spatially autocorrelated, either for all species or for only those species that were floating on the water when recorded. Neither Double-crested Cormorants (Phalacrocorax auritus) nor Herring Gulls exhibited spatial autocorrelation. In contrast, Bonaparte's and Ring-billed gulls exhibited positive spatial autocorrelations. Unlike marine studies, species density was only weakly associated with water depth. This result was due mainly to Double-crested Cormorants, the only diving bird species that lived year-round in the area, which preferred reefs and shoals (depth 3-6 m) over open water (10 m). The results suggest that offshore habitat influences species density in this area during the breeding and immediate post-breeding seasons.

  3. Habitat change by the formation of alien Crassostrea-reefs in the Wadden Sea and its role as feeding sites for waterbirds

    NASA Astrophysics Data System (ADS)

    Markert, Alexandra; Esser, Wiebke; Frank, Dietrich; Wehrmann, Achim; Exo, Klaus-Michael

    2013-10-01

    Non-indigenous Pacific oysters (Crassostrea gigas) have been invading the central Wadden Sea since 1998, predominantly settling on intertidal blue mussel (Mytilus edulis) beds which are increasingly transformed into Crassostrea-reefs. Pacific oysters are strong ecosystem engineers and the habitat change is considered to be a threat for waterbirds losing important feeding sites in the intertidal of the Wadden Sea. This study has increased our understanding of the use of foraging habitats by birds according to changing food resources. During the spring and autumn migration period in 2007, we recorded bird densities at two reef types varying in Pacific oyster density and at the adjacent sand flat as a reference site. We also recorded feeding behaviour, choice of prey and assessed peck and intake rate of three target species: Eurasian oystercatcher Haematopus ostralegus, Eurasian curlew Numenius arquata and European herring gull Larus argentatus. To evaluate the use of the Crassostrea-reef in the central Wadden Sea, we compared bird densities of the target species at different intertidal feeding habitats in various regions and compared the biomass intake of Eurasian oystercatcher feeding on different prey species. We show that Eurasian oystercatcher and Eurasian curlew have adapted to the new situation and learned to exploit the food supply offered by Crassostrea-reefs. While foraging mainly on Pacific oysters, Eurasian oystercatchers attained sustainable intake rates even though food resource at dense reef during autumn was very poor due to a lack in harvestable oysters. Consolidation of reefs limits the accessibility of prey for Eurasian oystercatchers whereas a successful recruitment of Pacific oysters enhances the suitability of the habitat. Eurasian curlew was promoted by the engineering effects of the Pacific oyster while feeding extensively on shore crabs at the reefs. In contrast, European herring gulls appear hampered in foraging during low tide and hereby

  4. Polycyclic Aromatic Hydrocarbons in Biota from the Brisbane River Estuary, Australia

    NASA Astrophysics Data System (ADS)

    Kayal, S.; Connell, D. W.

    1995-05-01

    Six species of aquatic organisms from the Brisbane River estuarine system were sampled and their tissues analysed for polycyclic aromatic hydrocarbons (PAHs). These were the sea mullet, Mugil cephalus, bony bream, Nematolosa come, blue catfish, Arius graffei, mud crab, Scylla serrata, pelican, Pelecanus conspicillatus, and silver gull, Larus novaehollandiae. PAHs in the muscle (fish and birds) and soft (crab) tissue samples were isolated by first hydrolysing these samples and then solvent extraction followed by column chromatography. The compounds were then identified and quantified by gas chromatography and gas chromatography coupled with mass spectrometry. The samples contained low levels of PAHs that ranged in molecular weight from 128 (naphthalene) to 252 (benzo[k]fluoranthene). The highest total PAH level of 195 ng g -1, wet weight, was recorded in mullet samples whereas the blue catfish samples yielded the lowest level of 43 ng g -1. Relative ratios of low molecular weight (≤3-rings) compounds to those with high molecular weights (≤4-rings) suggested a petroleum related origin for the PAHs detected in the organisms. Results indicated that significant biomagnification of PAHs in the estuarine ecosystem sampled is highly unlikely. Characteristics such as the trophic level and size/age were not significant factors in determining the corresponding tissue PAH levels in the fish and crab species. Tissue lipid content, however, was found to be a primary factor in determining the PAH concentrations in fish species. PAH levels recorded in the samples are comparable to those levels reported from similarly urbanized areas in other geographical locations.

  5. Immunological and reproductive health assessment in herring gulls and black-crowned night herons in the Hudson–Raritan Estuary

    USGS Publications Warehouse

    Grasman, Keith A.; Echols, Kathy R.; May, Thomas M.; Peterman, Paul H.; Gale, Robert W.; Orazio, Carl E.

    2013-01-01

    Previous studies have shown inexplicable declines in breeding waterbirds within western New York/New Jersey Harbor between 1996 and 2002 and elevated polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs) in double-crested cormorant (Phalacrocorax auritus) eggs. The present study assessed associations between immune function, prefledgling survival, and selected organochlorine compounds and metals in herring gulls (Larus argentatus) and black-crowned night herons (Nycticorax nycticorax) in lower New York Harbor during 2003. In pipping gull embryos, lymphoid cells were counted in the thymus and bursa of Fabricius (sites of T and B lymphocyte maturation, respectively). The phytohemagglutinin (PHA) skin response assessed T cell function in gull and heron chicks. Lymphocyte proliferation was measured in vitro in adult and prefledgling gulls. Reference data came from the Great Lakes and Bay of Fundy. Survival of prefledgling gulls was poor, with only 0.68 and 0.5 chicks per nest surviving to three and four weeks after hatch, respectively. Developing lymphoid cells were reduced 51% in the thymus and 42% in the bursa of gull embryos from New York Harbor. In vitro lymphocyte assays demonstrated reduced spontaneous proliferation, reduced T cell mitogen-induced proliferation, and increased B cell mitogen-induced proliferation in gull chicks from New York Harbor. The PHA skin response was suppressed 70 to 80% in gull and heron chicks. Strong negative correlations (r = –0.95 to –0.98) between the PHA response and dioxins and PCBs in gull livers was strong evidence suggesting that these chemicals contribute significantly to immunosuppression in New York Harbor waterbirds.

  6. Geographic, temporal, and age-specific variation in diets of Glaucous Gulls in western Alaska

    USGS Publications Warehouse

    Schmutz, J.A.; Hobson, K.A.

    1998-01-01

    We collected boluses and food remains of adult Glaucous Gulls (Larus hyperboreus) at or near nests and chicks, and digestive tracts from adults at three sites on the Yukon-Kuskokwim Delta, Alaska that differed in proximity to marine and terrestrial foods. We observed both geographic and temporal variation in diet; gulls consumed proportionately more terrestrial prey after peak hatch in late June, and gulls near the coast consumed proportionately more marine prey than gulls at two inland areas. Goslings occurred in > 60% of all samples from these inland areas. We compared these data to those from a previous study in western Alaska and found no marked differences. Evidence for similar patterns of geographic and temporal variation in diet was found using measurements of stable-carbon and nitrogen isotopes in gull and prey tissues. Stable isotope analysis further revealed that adult gulls consumed proportionately more marine prey (saffron cod, Eleginus gracilis) than they fed to their young. Using isotopic models, we estimated that 7-22% and 10-23% of the diet of adult and juvenile Glaucous Gulls, respectively, was comprised of terrestrial species. In addition to significant age-related variation, dietary estimates varied among geographic areas and between pre- and post-hatch periods. Overall, our isotopic estimates of the contribution of terrestrial prey to the diet of Glaucous Gulls was less than what may be inferred from conventional methods of diet analysis. Our study emphasizes the benefit of combining stable-isotope and conventional analyses to infer temporal and geographic changes in diet of wild birds and other organisms.

  7. Indicators of Marine Pollution in the North Pacific Ocean.

    PubMed

    Brown, Tanya M; Takada, Hideshige

    2017-08-01

    The complex nature of ocean pollution underscores the utility in identifying and characterizing a limited number of "indicators" that enables scientists and managers to track trends over space and time. This paper introduces a special issue on indicators of marine pollution in the North Pacific Ocean and builds on a scientific session that was held at the North Pacific Marine Science Organization. The special issue highlights studies using a variety of indicators to provide insight into the identification of legacy and emerging contaminants, the ranking of priority pollutants from various sources, and the effects of contaminants on ecosystem health in the North Pacific Ocean. Examples include the use of mussels to illustrate spatial and temporal trends of a number of contaminants following the 2011 tsunami in Japan, the use of molecular marker (linear alkylbenzenes, hopanes, and polycyclic aromatic hydrocarbons) profiles to identify pollution sources, and the use of plastic resin pellets to illustrate spatial trends of petroleum pollution around the world. Stable isotopes were used to strengthen the utility of the Glaucous-winged gull (Larus glaucescens) as an indicator of marine pollution. Examples also demonstrate the development and application of biomarker approaches, including gene transcripts, oxidative stress, estradiol, hatchability, and respiration and swimming behavior abnormalities, as a function of exposure to polychlorinated biphenyls, sulfur-diesel, Pinghu crude oil, galaxolide and antifouling biocides. We provide a brief review of indicators of marine pollution, identify research gaps, and summarize key findings from the articles published within the issue. This special issue represents the first compilation of research pertaining to marine pollution indicators in the North Pacific Ocean and provides guidance to inform mitigation and monitoring efforts of contaminants in the region.

  8. Mercury contamination and stable isotopes reveal variability in foraging ecology of generalist California gulls

    USGS Publications Warehouse

    Peterson, Sarah; Ackerman, Josh; Eagles-Smith, Collin A.

    2017-01-01

    Environmental contaminants are a concern for animal health, but contaminant exposure can also be used as a tracer of foraging ecology. In particular, mercury (Hg) concentrations are highly variable among aquatic and terrestrial food webs as a result of habitat- and site-specific biogeochemical processes that produce the bioaccumulative form, methylmercury (MeHg). We used stable isotopes and total Hg (THg) concentrations of a generalist consumer, the California gull (Larus californicus), to examine foraging ecology and illustrate the utility of using Hg contamination as an ecological tracer under certain conditions. We identified four main foraging clusters of gulls during pre-breeding and breeding, using a traditional approach based on light stable isotopes. The foraging cluster with the highest δ15N and δ34S values in gulls (cluster 4) had mean blood THg concentrations 614% (pre-breeding) and 250% (breeding) higher than gulls with the lowest isotope values (cluster 1). Using a traditional approach of stable-isotope mixing models, we showed that breeding birds with a higher proportion of garbage in their diet (cluster 2: 63–82% garbage) corresponded to lower THg concentrations and lower δ15N and δ34S values. In contrast, gull clusters with higher THg concentrations, which were more enriched in 15N and 34S isotopes, consumed a higher proportion of more natural, estuarine prey. δ34S values, which change markedly across the terrestrial to marine habitat gradient, were positively correlated with blood THg concentrations in gulls. The linkage we observed between stable isotopes and THg concentrations suggests that Hg contamination can be used as an additional tool for understanding animal foraging across coastal habitat gradients.

  9. Mercury levels in herring gulls and fish: 42 years of spatio-temporal trends in the Great Lakes.

    PubMed

    Blukacz-Richards, E Agnes; Visha, Ariola; Graham, Matthew L; McGoldrick, Daryl L; de Solla, Shane R; Moore, David J; Arhonditsis, George B

    2017-04-01

    Total mercury levels in aquatic birds and fish communities have been monitored across the Canadian Great Lakes by Environment and Climate Change Canada (ECCC) for the past 42 years (1974-2015). These data (22 sites) were used to examine spatio-temporal variability of mercury levels in herring gull (Larus argentatus) eggs, lake trout (Salvelinus namaycush), walleye (Sander vitreus), and rainbow smelt (Osmerus mordax). Trends were quantified with dynamic linear models, which provided time-variant rates of change of mercury concentrations. Lipid content (in both fish and eggs) and length in fish were used as covariates in all models. For the first three decades, mercury levels in gull eggs and fish declined at all stations. In the 2000s, trends for herring gull eggs reversed at two sites in Lake Erie and two sites in Lake Ontario. Similar trend reversals in the 2000s were observed for lake trout in Lake Superior and at a single station in Lake Ontario. Mercury levels in lake trout continued to slowly decline at all of the remaining stations, except for Lake Huron, where the levels remained stable. A post-hoc Bayesian regression analysis suggests strong trophic interactions between herring gulls and rainbow smelt in Lake Superior and Lake Ontario, but also pinpoints the likelihood of a trophic decoupling in Lake Huron and Lake Erie. Continued monitoring of mercury levels in herring gulls and fish is required to consolidate these trophic shifts and further evaluate their broader implications. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  10. How Do Growth and Sibling Competition Affect Telomere Dynamics in the First Month of Life of Long-Lived Seabird?

    PubMed

    Mizutani, Yuichi; Niizuma, Yasuaki; Yoda, Ken

    2016-01-01

    Telomeres are nucleotide sequences located at the ends of chromosomes that promote genome stability. Changes in telomere length (dynamics) are related to fitness or life expectancy, and telomere dynamics during the development phase are likely to be affected by growth and stress factors. Here, we examined telomere dynamics of black-tailed gull chicks (Larus crassirostris) in nests with and without siblings. We found that the initial telomere lengths of singletons at hatching were longer than those of siblings, indicating that singletons are higher-quality chicks than siblings in terms of telomere length. Other factors likely affecting individual quality (i.e., sex, laying date, laying order of eggs, and clutch size) were not related to telomere lengths. Within broods, initial telomere lengths were longer in older chicks than in younger chicks, suggesting that maternal effects, which vary with laying sequence, influence the initial lengths. Additionally, telomeres of chicks with a sibling showed more attrition between hatching and fledging than those of singleton chicks, suggesting that being raised with siblings can cause a sustained competitive environment that leads to telomere loss. High growth rates were associated with a low degree of telomere shortening observed in older siblings, perhaps because slower growth reflects higher food stress and/or higher aerobic metabolism from increased begging effort. Our results show that developmental telomere attrition was an inevitable consequence in two-chick nests in the pre- and post-hatching microenvironments due to the combination of social stress within the nest and maternal effects. The results of our study shed light on telomere dynamics in early life, which may represent an important physiological undercurrent of life-history traits.

  11. Changes in lagoonal marsh morphology at selected northeastern Atlantic coast sites of significance to migratory waterbirds

    USGS Publications Warehouse

    Erwin, R.M.; Sanders, G.M.; Prosser, D.J.

    2004-01-01

    Five lagoonal salt marsh areas, ranging from 220 ha to 3,670 ha, were selected from Cape Cod, Massachusetts to the southern DelMarVa peninsula, Virginia, USA to examine the degree to which Spartina marsh area and microhabitats had changed from the early or mid- 1900s to recent periods. We chose areas based on their importance to migratory bird populations, agency concerns about marsh loss and sea-level rise, and availability of historic imagery. We georeferenced and processed aerial photographs from a variety of sources ranging from 1932 to 1994. Of particular interest were changes in total salt marsh area, tidal creeks, tidal flats, tidal and non-tidal ponds, and open water habitats. Nauset Marsh, within Cape Cod National Seashore, experienced an annual marsh loss of 0.40% (19% from 1947 to 1994) with most loss attributed to sand overwash and conversion to open water. At Forsythe National Wildlife Refuge in southern New Jersey, annual loss was 0.27% (17% from 1932 to 1995), with nearly equal attribution of loss to open water and tidal pond expansion. At Curlew Bay, Virginia, annual loss was 0.20% (9% from 1949 to 1994) and almost entirely due to perimeter erosion to open water. At Gull Marsh, Virginia, a site chosen because of known erosional losses, we recorded the highest annual loss rate, 0.67% per annum, again almost entirely due to erosional, perimeter loss. In contrast, at the southernmost site, Mockhorn Island Wildlife Management Area, Virginia, there was a net gain of 0.09% per annum (4% from 1949 to 1994), with tidal flats becoming increasingly vegetated. Habitat. implications for waterbirds are considerable; salt marsh specialists such as laughing gulls (Larus atricilla), Forster's terns (Sterna forsteri), black rail, (Laterallus jamaicensis), seaside sparrow (Ammodramus maritimus), and saltmarsh sharp-tailed sparrow (Ammodramus caudacutus) are particularly at risk if these trends continue, and all but the laughing gull are species of concern to state

  12. Sex-specific foraging behavior in response to fishing activities in a threatened seabird

    PubMed Central

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-01-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

  13. Unintended Consequences of Management Actions in Salt Pond Restoration: Cascading Effects in Trophic Interactions

    PubMed Central

    Takekawa, John Y.; Ackerman, Joshua T.; Brand, L. Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark P.; Topping, Brent R.; Shellenbarger, Gregory G.; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  14. Terrestrial and Marine Foraging Strategies of an Opportunistic Seabird Species Breeding in the Wadden Sea.

    PubMed

    Garthe, Stefan; Schwemmer, Philipp; Paiva, Vitor H; Corman, Anna-Marie; Fock, Heino O; Voigt, Christian C; Adler, Sven

    2016-01-01

    Lesser black-backed gulls Larus fuscus are considered to be mainly pelagic. We assessed the importance of different landscape elements (open sea, tidal flats and inland) by comparing marine and terrestrial foraging behaviours in lesser black-backed gulls breeding along the coast of the southern North Sea. We attached GPS data loggers to eight incubating birds and collected information on diet and habitat use. The loggers recorded data for 10-19 days to allow flight-path reconstruction. Lesser black-backed gulls foraged in both offshore and inland areas, but rarely on tidal flats. Targets and directions were similar among all eight individuals. Foraging trips (n = 108) lasted 0.5-26.4 h (mean 8.7 h), and ranges varied from 3.0-79.9 km (mean 30.9 km). The total distance travelled per foraging trip ranged from 7.5-333.6 km (mean 97.9 km). Trips out to sea were significantly more variable in all parameters than inland trips. Presence in inland areas was closely associated with daylight, whereas trips to sea occurred at day and night, but mostly at night. The most common items in pellets were grass (48%), insects (38%), fish (28%), litter (26%) and earthworms (20%). There was a significant relationship between the carbon and nitrogen isotope signals in blood and the proportional time each individual spent foraging at sea/land. On land, gulls preferentially foraged on bare ground, with significantly higher use of potato fields and significantly less use of grassland. The flight patterns of lesser black-backed gulls at sea overlapped with fishing-vessel distribution, including small beam trawlers fishing for shrimps in coastal waters close to the colony and large beam-trawlers fishing for flatfish at greater distances. Our data show that individuals made intensive use of the anthropogenic landscape and seascape, indicating that lesser black-backed gulls are not a predominantly marine species during the incubation period.

  15. DNA fingerprinting reveals elevated mutation rates in herring gulls inhabiting a genotoxically contaminated site

    SciTech Connect

    Yauk, C.L.; Quinn, J.S.

    1995-12-31

    The authors used multi-locus DNA fingerprinting to examine families of herring gulls (Larus argentatus) from a genotoxically contaminated site (Hamilton Harbour) and from a pristine location (Kent Island, Bay of Fundy) to show significant differences in mutation rates between the locations. Overall the authors identified 17 mutant bands from 15 individuals of the 35 examined from Hamilton Harbour, and 7 mutant fragments from 7 individuals, of the 43 examined from Kent Island; a mutation frequency of 0.429 per nestling for Hamilton Harbour and 0.163 for Kent Island. The total number of individuals with mutant bands was significantly higher at Hamilton Harbour than at Kent Island (X{sup 2}=6.734; df = 1; P < 0.01). Ongoing analysis of other less contaminated sites also reveals lower mutation rates than those seen in Hamilton Harbour. With multi-locus DNA fingerprinting many regions of the genome can be surveyed simultaneously. The tandemly repeated arrays of nucleotides examined with DNA fingerprinting are known to have elevated rates of mutation. Furthermore, the mutations seen with DNA fingerprinting are predominantly heritable. Other biomarkers currently used in situ are not able to monitor direct and heritable DNA mutation, or measure biological endpoints that frequently result in spontaneous abortion creating difficulty in observing significantly elevated levels in viable offspring. The authors suggest that multilocus DNA fingerprinting can be used as a biomarker to identify potentially heritable risks before the onset of other types of ecological damage. This approach provides a direct measure of mutation in situ and in vivo in a vertebrate species under ambient conditions.

  16. A long-term retrospective study on rehabilitation of seabirds in Gran Canaria Island, Spain (2003-2013).

    PubMed

    Montesdeoca, Natalia; Calabuig, Pascual; Corbera, Juan A; Orós, Jorge

    2017-01-01

    The aims of this study were to analyze the causes of morbidity and mortality in a large population of seabirds admitted to the Tafira Wildlife Rehabilitation Center (TWRC) in Gran Canaria Island, Spain, from 2003 to 2013, and to analyze the outcomes of the rehabilitation process. We included 1,956 seabirds (133 dead on admission and 1,823 admitted alive) in this study. Causes of morbidity were classified into nine categories: light pollution (fallout), fishing gear interaction, crude oil, poisoning/intoxication, other traumas, metabolic/nutritional disorder, orphaned young birds, other causes, and unknown/undetermined. The crude and stratified (by causes of admission) rates of the three final disposition categories (euthanasia Er, unassisted mortality Mr, and release Rr), the time until death, and the length of stay were also studied for the seabirds admitted alive. Yellow-legged Gull (Larus michahellis) was the species most frequently admitted (46.52%), followed by Cory's Shearwater (Calonectris diomedea borealis) (20.09%). The most frequent causes of morbidity were light pollution (fallout) (25.81%), poisoning/intoxication (24.69%), and other traumas (18.14%). The final disposition rates were: Er = 15.35%, Mr = 16.29%, and Rr = 68.34%. The highest Er was observed in the 'other traumas' category (58.08%). Seabirds admitted due to metabolic/nutritional disorder had the highest Mr (50%). The highest Rr was observed in the light pollution (fallout) category (99.20%). This survey provides useful information for the conservation of several seabird species. We suggest that at least the stratified analysis by causes of admission of the three final disposition rates, and the parameters time until death and length of stay at the center should be included in the outcome research of the rehabilitation of seabirds. The high release rate for seabirds (68.34%) achieved at the TWRC emphasizes the importance of wildlife rehabilitation centers for the conservation of seabirds.

  17. [Microphallus kurilensis sp. nov., a new species of microphallids from the pygmaeus species group (Trematoda, Microphallidae) from the coastal areas of Okhotsk and Bering Seas].

    PubMed

    Galaktionov, K V; Regel', K V; Atrashkevich, G I

    2010-01-01

    The pygmaeus-species group is composed of close related species from the genus Microphallus in which metacercariae develop inside daughter sporocysts without encystment. Infection of periwinkles Littorina (Neritremna) spp. with intramolluscan stages of a new species of this group (Microphallus kurilensis sp. nov.) was recorded on the coasts of Sakhalin and Kuril islands, north of the Sea of Okhotsk and Chukchi Peninsula (the Bering Sea). Application of molecular methods allowed us to establish that M. kurilensis metacercariae are conspecific with one of the morphotypes of microphallid adults obtained from the intestine of the Pacific common eider (Somateria mollissima v-nigrum), which was shot in the north of the Sea of Okhotsk (Galaktionov, Olson, and Blasco-Costa, in press). The adults of the same morphotype were recorded in the Pacific common eider from the northwestern part of the Bering Sea (Chukchi Peninsula). In the course of experimental infection of the slaty-backed gull Larus schistisagus chicks with metacercariae of M. kurilensis, few microphallid adults were obtained. These adults were identical in their morphology with specimens of the microphallid morphotype from the Pacific common eider, which had been identified as M. kurilensis based on molecular data. Morphological description of metacercaria and adult of M. kurilensis and list of their differences from the same developmental stages of other species from pygmaeus-group are provided. It is concluded that M. kurilensis is transmitted in the host system including periwinkle Littorina (Neritrema) and seaducks (predominately, Pacific common eider). Most probably, distribution of M. kurilensis is not limited by the north Asiatic coast but expanded to the North American coast of the Pacific Ocean.

  18. Antibiotic-resistant Escherichia coli bacteria, including strains with genes encoding the extended-spectrum beta-lactamase and QnrS, in waterbirds on the Baltic Sea Coast of Poland.

    PubMed

    Literak, Ivan; Dolejska, Monika; Janoszowska, Dagmar; Hrusakova, Jolana; Meissner, Wlodzimierz; Rzyska, Hanna; Bzoma, Szymon; Cizek, Alois

    2010-12-01

    Individual cloacal swabs of mallards (Anas platyrhynchos) and of herring gulls (Larus argentatus), as well as samples of waterbird feces obtained in 2008 and 2009, were cultivated for Escherichia coli. Isolates of E. coli were tested for susceptibilities to 12 antimicrobial agents by the disk diffusion method. Moreover, the samples were subcultivated on MacConkey agar (MCA) containing cefotaxime (2 mg liter(-1)) to detect E. coli with extended-spectrum beta-lactamase (ESBL) and subsequently on MCA supplemented with ciprofloxacin (0.05 mg liter(-1)) and MCA with nalidixic acid (20 mg liter(-1)) to isolate fluoroquinolone-resistant E. coli. PCR was used to detect specific antibiotic resistance genes. We found 9 E. coli isolates producing ESBL with bla genes: bla(CTX-M-1) (6 isolates), bla(CTX-M-9) plus bla(TEM-1b) (1 isolate), bla(CTX-M-15) plus bla(OXA-1) (1 isolate), and bla(SHV-12) (1 isolate). In the isolate with bla(CTX-M-15), the gene aac(6)-Ib-cr was also detected. The bla genes were harbored by transferable plasmids of the IncN and IncI1 groups. Nine quinolone-resistant E. coli isolates with qnrS genes were found and characterized. The gene qnrS was associated with a Tn3-like transposon on the IncX1 plasmid together with bla(TEM-1) in two isolates. The gene qnrS was also harbored by conjugative plasmids of the IncN and IncX2 groups. Even if populations of wild birds are not directly influenced by antibiotic practice, we have demonstrated that antibiotic-resistant E. coli strains, including strains with various ESBL and qnrS genes, are found in the feces of wild birds on the coast of the Baltic Sea in Poland.

  19. Changing gull diet in a changing world: a 150-year stable isotope (δ13C, δ15N) record from feathers collected in the Pacific Northwest of North America.

    PubMed

    Blight, Louise K; Hobson, Keith A; Kyser, T Kurt; Arcese, Peter

    2015-04-01

    The world's oceans have undergone significant ecological changes following European colonial expansion and associated industrialization. Seabirds are useful indicators of marine food web structure and can be used to track multidecadal environmental change, potentially reflecting long-term human impacts. We used stable isotope (δ(13)C, δ(15)N) analysis of feathers from glaucous-winged gulls (Larus glaucescens) in a heavily disturbed region of the northeast Pacific to ask whether diets of this generalist forager changed in response to shifts in food availability over 150 years, and whether any detected change might explain long-term trends in gull abundance. Sampled feathers came from birds collected between 1860 and 2009 at nesting colonies in the Salish Sea, a transboundary marine system adjacent to Washington, USA and British Columbia, Canada. To determine whether temporal trends in stable isotope ratios might simply reflect changes to baseline environmental values, we also analysed muscle tissue from forage fishes collected in the same region over a multidecadal timeframe. Values of δ(13)C and δ(15)N declined since 1860 in both subadult and adult gulls (δ(13)C, ~ 2-6‰; δ(15)N, ~4-5‰), indicating that their diet has become less marine over time, and that birds now feed at a lower trophic level than previously. Conversely, forage fish δ(13)C and δ(15)N values showed no trends, supporting our conclusion that gull feather values were indicative of declines in marine food availability rather than of baseline environmental change. Gradual declines in feather isotope values are consistent with trends predicted had gulls consumed less fish over time, but were equivocal with respect to whether gulls had switched to a more garbage-based diet, or one comprising marine invertebrates. Nevertheless, our results suggest a long-term decrease in diet quality linked to declining fish abundance or other anthropogenic influences, and may help to explain regional

  20. Summer distribution of seabirds in the North-East Water polynya, Greenland

    NASA Astrophysics Data System (ADS)

    Joiris, Claude R.; Kampp, Kaj; Tahon, Jacques; Kristensen, Reinhardt Møbjerg

    1997-10-01

    The distribution at sea of seabirds was studied in the North-East Water (NEW) polynya, Greenland, during transect counts in the summers of 1991, 1992 and 1993 on board the ice-breaking RVs Polarstern and Polar Sea. Data collected within the polynya 'box' (78-82°N; 5-18°W) concern observations of 8000 birds counted during 1350 half-hour counts. Distribution is presented as density (N/km 2) and calculated daily food intake. Five bird species were selected for discussion, representing more than 95% of the total numbers encountered: Fulmar ( Fulmarus glacialis), Ivory Gull ( Pagophila eburnea), Kittiwake ( Rissa tridactyla), Glaucous Gull ( Larus hyperboreus) and Ross's Gull ( Rhodostethia rosea). For these species, densities are comparable in the NE Greenland polynya and in other European Arctic seas. The main difference is the absence in NEW of the species playing the main role in Arctic seas: Brünnich's Guillemot ( Uria lomvia) and Little Auk ( Alle alle). In the absence of fish-eating birds and of birds consuming zooplankton in the water column, the NEW polynya ecosystem is thus dominated by surface feeders and, closer to the coast, by benthic feeders like eiders, Somateria mollissima and S. spectabilis, and walrus, Odobenus rosmarus. The density and daily food intake for all seabirds are one order of magnitude lower in the polynya than in the Arctic seas. The distribution and abundance of seabirds in the NEW polynya seems to reflect a very low density of pelagic fish and Zooplankton in the water column, while Zooplankton must be present at 'normal' concentrations in the upper layer.

  1. Spatio-temporal trends and monitoring design of perfluoroalkyl acids in the eggs of gull (Larid) species from across Canada and parts of the United States.

    PubMed

    Gewurtz, Sarah B; Martin, Pamela A; Letcher, Robert J; Burgess, Neil M; Champoux, Louise; Elliott, John E; Weseloh, D V Chip

    2016-09-15

    A large spatial dataset of perfluoroalkyl acid (PFAA) concentrations in eggs of herring gulls (Larus argentatus or congeneric species) collected from late April to early June between 2009 and 2014 from 28 colonies across Canada and parts of the Unites States was used to evaluate location-specific patterns in chemical concentrations and to generate hypotheses on the major sources affecting PFAA distributions. The highly bioaccumulative perfluorooctane sulfonic acid (PFOS) as well as other perfluoroalkyl sulfonic acids (PFSAs) showed the greatest concentrations in eggs from the lower Great Lakes of southern Ontario as well as from the St. Lawrence River. Despite the 2000 to 2002 phase-out of PFOS and related C8 chemistry by the major manufacturer at the time, ongoing losses from consumer products during use and disposal in urban/industrial locations continue to be major sources to the environment and are influencing the spatial trends of PFOS in Canada. In comparison to PFOS, perfluoroalkyl carboxylic acids (PFCAs) were not as concentrated in eggs in close proximity to urbanized/industrialized centers, but had surprisingly elevated levels in relatively remote regions such as Great Slave Lake, NT and East Bay in Hudson Bay, NU. The present results support the hypothesis that atmospheric transport and degradation of precursor chemicals, such as the fluorotelomer alcohols 8:2 FTOH and 10:2 FTOH, are influencing the spatial trends of PFCAs in Canada. A power analysis conducted on a representative urbanized/industrialized colony in the Toronto Harbour, ON, and a relatively remote colony in Lake Superior, emphasized the importance of consistent and long-term data collection in order to detect the anticipated changes in PFAA concentrations in Canadian gull eggs. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  2. How Do Growth and Sibling Competition Affect Telomere Dynamics in the First Month of Life of Long-Lived Seabird?

    PubMed Central

    Mizutani, Yuichi; Niizuma, Yasuaki; Yoda, Ken

    2016-01-01

    Telomeres are nucleotide sequences located at the ends of chromosomes that promote genome stability. Changes in telomere length (dynamics) are related to fitness or life expectancy, and telomere dynamics during the development phase are likely to be affected by growth and stress factors. Here, we examined telomere dynamics of black-tailed gull chicks (Larus crassirostris) in nests with and without siblings. We found that the initial telomere lengths of singletons at hatching were longer than those of siblings, indicating that singletons are higher-quality chicks than siblings in terms of telomere length. Other factors likely affecting individual quality (i.e., sex, laying date, laying order of eggs, and clutch size) were not related to telomere lengths. Within broods, initial telomere lengths were longer in older chicks than in younger chicks, suggesting that maternal effects, which vary with laying sequence, influence the initial lengths. Additionally, telomeres of chicks with a sibling showed more attrition between hatching and fledging than those of singleton chicks, suggesting that being raised with siblings can cause a sustained competitive environment that leads to telomere loss. High growth rates were associated with a low degree of telomere shortening observed in older siblings, perhaps because slower growth reflects higher food stress and/or higher aerobic metabolism from increased begging effort. Our results show that developmental telomere attrition was an inevitable consequence in two-chick nests in the pre- and post-hatching microenvironments due to the combination of social stress within the nest and maternal effects. The results of our study shed light on telomere dynamics in early life, which may represent an important physiological undercurrent of life-history traits. PMID:27902754

  3. Current concentrations and spatial and temporal trends in mercury in Great Lakes Herring Gull eggs, 1974-2009.

    PubMed

    Weseloh, D V Chip; Moore, David J; Hebert, Craig E; de Solla, Shane R; Braune, Birgit M; McGoldrick, Daryl J

    2011-10-01

    Current concentrations and spatial and temporal trends of total mercury (Hg) were assessed in eggs of the Herring Gull (Larus argentatus) over the period 1974-2009 at 15 sites in the Great Lakes: 2-3 sites per lake and one site in each of 3 connecting channels. Current (2009) concentrations ranged from 0.064 μg/g (wet weight) at Chantry Island (Lake Huron) to 0.246 μg/g at Middle Island (Lake Erie). There were significant inter-colony differences in mean Hg concentrations (2005-2009). Mercury concentrations at 14 of 15 sites declined from 23 to 86% between when it was first measured (usually 1974) and 2009. Declining temporal trends over the entire period (1974-2009) were significant at 10 of the 15 sites. On the other hand, there were no significant trends in mercury over the last 15 years. In the early years, declines of Hg in Herring Gull eggs tracked those in Rainbow Smelt (Osmerus mordax) in most Great Lakes. More recently, declines in gull eggs were more evident than in smelt and may be partially explained by temporal changes in the gull diet. When gull Hg data were adjusted for temporal changes in the gull diet, as inferred from stable nitrogen isotope values in eggs, significant declines in egg mercury levels were found only at 4 of 15 sites. Overall, Hg concentrations have declined in Great Lakes Herring Gull eggs over the period 1974-2009 but changes in the gull diet may be contributing, in part, to those declines. Examination of contaminant temporal trends in multiple indicator species will ensure accurate inferences regarding contaminant availability in the environment.

  4. Perfluorinated sulfonate and carboxylate compounds and precursors in herring gull eggs from across the Laurentian Great Lakes of North America: Temporal and recent spatial comparisons and exposure implications.

    PubMed

    Letcher, Robert J; Su, Guanyong; Moore, Jeremy N; Williams, Lisa L; Martin, Pamela A; de Solla, Shane R; Bowerman, William W

    2015-12-15

    Chemicals of emerging concern (CECs) in the basin of the Laurentian Great Lakes of North America include per- and poly-fluoroalkyl substances (PFASs) classified as perfluoroalkyl acids. We investigated several PFASs, and specifically 13 C4-C16 perfluorinated carboxylic acids (PFCAs), 4 (C4, C6, C8 and C10) perfluorinated sulfonates (PFSAs), perfluoro-4-ethylcyclohexane sulfonate (PFEtCHxS) and selected precursors (e.g. perfluorobutane sulfonamide and perfluorooctane sulfonamide) in herring gull (Larus argentatus) eggs collected in 2012-2013 from 19 Canadian and U.S. colony sites across the Great Lakes. C6, C8 and C10 PFSAs, PFEtCHxS, and C7-14 and C16 PFCAs were quantifiable at >97% of the 114 egg samples. PFEtCHxS concentrations ranged from n.d. to 3.1ng/g ww (highest in Lake Michigan eggs). Mean Σ4PFSA (92 to 97% perfluorooctane sulfonate (PFOS)) and Σ9PFCA concentration ranges were 44 to 740 and 4.8 to 118ng/g ww, respectively. Σ4PFSA showed a clear increasing concentration trend from the northwest to the southeast colonies. Also, Σ4PFCA to Σ9PFSA concentration ratios in gull eggs were greater in eggs from Lake Superior relative to colonies in the other lakes. PFOS concentrations in some egg samples were greater than some of the known lowest observed effect concentrations (LOECs) measured and reported in captive bird model studies. This study showed the increasing complexity of PFAS-CECs, and emphasized the importance of continuing monitoring of bioaccumulative PFAS in Great Lakes herring gulls. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Volatile Methylsiloxanes and Organophosphate Esters in the Eggs of European Starlings (Sturnus vulgaris) and Congeneric Gull Species from Locations across Canada.

    PubMed

    Lu, Zhe; Martin, Pamela A; Burgess, Neil M; Champoux, Louise; Elliott, John E; Baressi, Enzo; De Silva, Amila O; de Solla, Shane R; Letcher, Robert J

    2017-09-05

    Volatile methylsiloxanes (VMSs) and organophosphate esters (OPEs) are two suites of chemicals that are of environmental concern as organic contaminants, but little is known about the exposure of wildlife to these contaminants, particularly in birds, in terrestrial and aquatic ecosystems. The present study investigates the spatial distributions of nine cyclic and linear VMSs and 17 OPEs in the eggs of European starlings (Sturnus vulgaris) and three congeneric gull species (i.e., herring gull (Larus argentatus), glaucous-winged gull (L. glaucescens), and California gull (L. californicus)) from nesting sites across Canada. ∑VMS concentrations for all bird eggs were dominated by decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and octamethylcyclotetrasiloxane (D4). With European starlings, birds breeding adjacent to landfill sites had eggs containing significantly greater ∑VMS concentrations (median: 178 ng g(-1) wet weight (ww)) compared with those from the urban industrial (20 ng g(-1) ww) and rural sites (1.3 ng g(-1) ww), indicating that the landfills are important sources of VMSs to Canadian terrestrial environments. In gull eggs, the median ∑VMS concentrations were up to 254 ng g(-1) ww and suggested greater detection frequencies and levels of VMSs in aquatic- versus terrestrial-feeding birds in Canada. In contrast, the detection frequency of OPEs in all European starling and gull eggs was lower than 16%. This suggested that low dietary exposure or rapid metabolism of accumulated OPEs occurs in aquatic feeding birds and may warrant further investigation for the elucidation of the reasons for these differences.

  6. Avian botulism type E in waterbirds of Lake Michigan, 2010–2013

    USGS Publications Warehouse

    Chipault, Jennifer G.; White, C. LeAnn; Blehert, David S.; Jennings, Susan K.; Strom, Sean M.

    2015-01-01

    During 2010 to 2013, waterbird mortality surveillance programs used a shared protocol for shoreline walking surveys performed June to November at three areas in northern Lake Michigan. In 2010 and 2012, 1244 total carcasses (0.8 dead bird/km walked) and 2399 total carcasses (1.2 dead birds/km walked), respectively, were detected. Fewer carcasses were detected in 2011 (353 total carcasses, 0.2 dead bird/km walked) and 2013 (451 total carcasses, 0.3 dead bird/km walked). During 3 years, peak detection of carcasses occurred in October and involved primarily migratory diving and fish-eating birds, including long-tailed ducks (Clangula hyemalis; 2010), common loons (Gavia immer; 2012), and red-breasted mergansers (Mergus serrator; 2013). In 2011, peak detection of carcasses occurred in August and consisted primarily of summer residents such as gulls (Larus spp.) and double-crested cormorants (Phalacrocorax auritus). A subset of fresh carcasses was collected throughout each year of the study and tested for botulinum neurotoxin type E (BoNT/E). Sixty-one percent of carcasses (57/94) and 10 of 11 species collected throughout the sampling season tested positive for BoNT/E, suggesting avian botulism type E was a major cause of death for both resident and migratory birds in Lake Michigan. The variety of avian species affected by botulism type E throughout the summer and fall during all 4 years of coordinated surveillance also suggests multiple routes for bird exposure to BoNT/E in Lake Michigan.

  7. Gut content analysis of Lake Michigan waterbirds in years with avian botulism type E mortality, 2010–2012

    USGS Publications Warehouse

    Essian, David A.; Chipault, Jennifer G.; Lafrancois, Brenda M.; Leonard, Jill B.K.

    2016-01-01

    Waterbird die-offs caused by Clostridium botulinum neurotoxin type E (BoNT/E) have occurred sporadically in the Great Lakes since the late 1960s, with a recent pulse starting in the late 1990s. In recent die-offs, round gobies (Neogobius melanostomus) have been implicated as vectors for the transfer of BoNT/E to fish-eating birds due to the round goby invasion history and their importance as prey. Dreissenid mussels (Dreissena spp.) are also potentially involved in BoNT/E transmission to birds and round gobies. We examined gut contents of waterbirds collected in Lake Michigan during die-offs in 2010–2012, and the gut contents of culled, presumably BoNT/E-free double-crested cormorants (Phalacrocorax auritus). Round gobies were found in 86% of the BoNT/E-positive individuals, 84% of the BoNT/E-negative birds, and 94% of the BoNT/E-free cormorants examined. Double-crested cormorants, ring-billed gulls (Larus delewarensis), and common loons (Gavia immer) consumed larger-sized round gobies than horned and red-necked grebes (Podiceps auritus and Podiceps grisegena), white-winged scoters (Melanitta deglandi), and long-tailed ducks (Clangula hymealis). Other common prey included dreissenid mussels, terrestrial insects, and alewives (Alosa pseudoharengus). Our data emphasize the importance of round gobies and mussels in diets of Lake Michigan waterbirds and suggest they may play a role in the transfer of BoNT/E to waterbirds; however, round gobies and mussels were found in BoNT/E-positive, -negative, and -free individuals, suggesting that other factors, such as alternative trophic pathways for toxin transfer, bird migratory timing and feeding locations, prey behavior, and individual physiological differences across birds may affect the likelihood that a bird will succumb to BoNT/E intoxication.

  8. Comparative skeletal muscle fibre morphometry among wild birds with different locomotor behaviour

    PubMed Central

    TORRELLA, J. R.; FOUCES, V.; PALOMEQUE, J.; VISCOR, G.

    1998-01-01

    Six muscles of the mallard duck (Anas platyrhynchos), the common coot (Fulica atra) and the yellow-legged gull (Larus cachinnans) were analysed morphometrically, with special emphasis on their functional implications and physiological needs. Oxidative fibres always had significantly smaller size than anaerobic fibres, although no differences in the number of capillaries per fibre were found. This resulted in greater capillary counts per unit of fibre area and perimeter in oxidative than anaerobic fibres, which indicates that the greater demand for oxygen supply may be achieved by decreasing the size of the muscle fibre rather than by increasing the number of associated capillaries. Fast oxidative fibres of the pectoralis and the triceps of the gull had greater sizes than the fast oxidative fibres of the mallard and the coot, which correlates with the difference in energetic demands between flapping and gliding flight. Greater fibre cross-sectional areas and perimeters seem suited to afford the long-lasting activity with low metabolic demands required during gliding. By contrast, mallards and coots attain a high oxidative metabolism, during sustained flapping flight, by reducing fibre size at the expense of a diminished ability for force generation. Between-species comparisons of the hindlimb muscles only yielded differences for the anaerobic fibres of the gastrocnemius, as an important adaptive response to force generation during burst locomotion. The need to manage sustained swimming abilities effectively may result in similar FOG fibre morphometry of the hindlimb muscles studied, indicating that a compromise between the oxygen flux to the muscle cell and the development of power is highly optimised in oxidative fibres of the bird species studied. PMID:9643422

  9. Body distribution of trace elements in black-tailed gulls from Rishiri Island, Japan: age-dependent accumulation and transfer to feathers and eggs.

    PubMed

    Agusa, Tetsuro; Matsumoto, Taro; Ikemoto, Tokutaka; Anan, Yasumi; Kubota, Reiji; Yasunaga, Genta; Kunito, Takashi; Tanabe, Shinsuke; Ogi, Haruo; Shibata, Yasuyuki

    2005-09-01

    Body distribution and maternal transfer of 18 trace elements (V, Cr, Mn, Co, Cu, Zn, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Hg, Tl, and Pb) to eggs were examined in black-tailed gulls (Larus crassirostris), which were culled in Rishiri Island, Hokkaido Prefecture, Japan. Manganese, Cu, Rb, Mo, and Cd showed the highest levels in liver and kidney, Ag, Sb, and Hg in feather, and V, Sr, and Pb in bone. Maternal transfer rates of trace elements ranged from 0.8% (Cd) to as much as 65% (Tl) of maternal body burden. Large amounts of Sr, Ba, and Tl were transferred to the eggs, though maternal transfer rates of V, Cd, Hg, and Pb were substantially low. It also was observed that Rb, Sr, Cd, Cs, and Ba hardly were excreted into feathers. Concentrations of Co in liver, Ba in liver and kidney, and Mo in liver increased significantly with age, whereas Se in bone and kidney, Hg in kidney, and Cr in feather decreased with age in the known-aged black-tailed gulls (2-20 years old). It also was suggested that feathers might be useful to estimate contamination status of trace elements in birds, especially for Hg on a population basis, although the utility is limited on an individual basis for the black-tailed gulls. To our knowledge, this is the first report on the maternal transfer rate of multielements and also on the usefulness of feathers to estimate contamination status of Hg in birds on a population basis.

  10. Immunological and reproductive health assessment in herring gulls and black-crowned night herons in the Hudson-Raritan Estuary.

    PubMed

    Grasman, Keith A; Echols, Kathy R; May, Thomas M; Peterman, Paul H; Gale, Robert W; Orazio, Carl E

    2013-03-01

    Previous studies have shown inexplicable declines in breeding waterbirds within western New York/New Jersey Harbor between 1996 and 2002 and elevated polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs) in double-crested cormorant (Phalacrocorax auritus) eggs. The present study assessed associations between immune function, prefledgling survival, and selected organochlorine compounds and metals in herring gulls (Larus argentatus) and black-crowned night herons (Nycticorax nycticorax) in lower New York Harbor during 2003. In pipping gull embryos, lymphoid cells were counted in the thymus and bursa of Fabricius (sites of T and B lymphocyte maturation, respectively). The phytohemagglutinin (PHA) skin response assessed T cell function in gull and heron chicks. Lymphocyte proliferation was measured in vitro in adult and prefledgling gulls. Reference data came from the Great Lakes and Bay of Fundy. Survival of prefledgling gulls was poor, with only 0.68 and 0.5 chicks per nest surviving to three and four weeks after hatch, respectively. Developing lymphoid cells were reduced 51% in the thymus and 42% in the bursa of gull embryos from New York Harbor. In vitro lymphocyte assays demonstrated reduced spontaneous proliferation, reduced T cell mitogen-induced proliferation, and increased B cell mitogen-induced proliferation in gull chicks from New York Harbor. The PHA skin response was suppressed 70 to 80% in gull and heron chicks. Strong negative correlations (r = -0.95 to -0.98) between the PHA response and dioxins and PCBs in gull livers was strong evidence suggesting that these chemicals contribute significantly to immunosuppression in New York Harbor waterbirds.

  11. Habitat comparisons and productivity in nesting common terns on the mid-Atlantic coast

    USGS Publications Warehouse

    Erwin, R.M.; Smith, D.C.

    1985-01-01

    Nesting Common Terns (Sterna hirundo) were studied at a number of barrier beaches and small islands of tidal salt marsh in New Jersey and the Eastern Shore of Maryland-Virginina from 1980 through 1982. Data were collected on clutch sizes, nest spacing, and nesting success. The principal null hypothesis tested was that no difference in reproductive success exists between beach and marsh habitats. Nests were monitored from egg-laying in mid-May until mid-July when young fledged. Clutch sizes varied among colonies and across years but no systematic effect of year, habitat, or colony size on mean clutch size per colony was detected. Analyses of nest productivity (estimated using both the Mayfield method and using a colony average) failed to reveal significant effects of habitat or colony size but showed a stronger year effect. Storm tide flooding and egg chick disappearance (presumably predation by Herring Gulls Larus argentatus and Laughing Gulls L. atricilla nesting nearby) accounted for most nest failures. Losses due to both these mortality factors were unpredictable from year to year. Nest spacing in salt marsh colonies was much closer than it was on barrier beaches. In mixed-species colonies with Black Skimmers (Rynchops niger), distances between tern and skimmer nests were also much smaller in marsh colonies than they were on beaches. The limited amount of wrack (windrows of dead, matted vegetation) preferred by marsh-nesting terns probably explains these spacing differences. Several lines of evidence suggest that terns prefer beaches to marshes for nesting, however, the uncertainty of predation and flooding may often obscure any intrinsic differences in habitat quality. Long-term field studies are essential for testing hypotheses related to differential fitness of individuals among habitats.

  12. Toxoplasma gondii Infection in Seagull Chicks Is Related to the Consumption of Freshwater Food Resources

    PubMed Central

    Cabezón, Oscar; Cerdà-Cuéllar, Marta; Morera, Virginia; García-Bocanegra, Ignacio; González-Solís, Jacob; Napp, Sebastian; Ribas, Maria P.; Blanch-Lázaro, Berta; Fernández-Aguilar, Xavier; Antilles, Noelia; López-Soria, Sergio; Lorca-Oró, Cristina; Dubey, Jitender P.; Almería, Sonia

    2016-01-01

    Understanding the spread of Toxoplasma gondii (T. gondii) in wild birds, particularly in those with opportunistic feeding behavior, is of interest for elucidating the epidemiological involvement of these birds in the maintenance and dissemination of the parasite. Overall, from 2009 to 2011, we collected sera from 525 seagull chicks (Yellow-legged gull (Larus michahellis) and Audouin’s gull (L. audouinii)) from 6 breeding colonies in Spain and tested them using the modified agglutination test (MAT) for the presence of antibodies against T. gondii. Chick age was estimated from bill length. Main food source of seagull chicks was evaluated using stable isotope analyses from growing scapular feathers. Overall T. gondii seroprevalence was 21.0% (IC95% 17.5–24.4). A generalized linear mixed-effects model indicated that year (2009) and food source (freshwater) were risk factors associated to the individual risk of infection by T. gondii, while age (days) was close to significance. Freshwater food origin was related to the highest seroprevalence levels, followed by marine origin, supporting freshwater and sewages as important routes of dispersion of T. gondii. Year differences could indicate fluctuating rates of exposure of seagull chicks to T. gondii. Age ranged from 4 to 30 days and seropositivity tended to increase with age (P = 0.07), supporting that seropositivity is related to T. gondii infection rather than to maternal transfer of antibodies, which in gulls is known to sharply decrease with chick age. This study is the first to report T. gondii antibodies in Yellow-legged and Audouin’s gulls, thereby extending the range of intermediate hosts for this parasite and underscoring the complexity of its epidemiology. PMID:26974667

  13. Temporal trends of mercury in eggs of five sympatrically breeding seabird species in the Canadian Arctic.

    PubMed

    Braune, Birgit M; Gaston, Anthony J; Mallory, Mark L

    2016-07-01

    We compared temporal trends of total mercury (Hg) in eggs of five seabird species breeding at Prince Leopold Island in the Canadian high Arctic. As changes in trophic position over time have the potential to influence contaminant temporal trends, Hg concentrations were adjusted for trophic position (measured as δ(15)N). Adjusted Hg concentrations in eggs of thick-billed murres (Uria lomvia) and northern fulmars (Fulmarus glacialis) increased from 1975 to the 1990s, followed by a plateauing of levels from the 1990s to 2014. Trends of adjusted Hg concentrations in eggs of murres, fulmars, black guillemots (Cepphus grylle) and black-legged kittiwakes (Rissa tridactyla) had negative slopes between 1993 and 2013. Adjusted Hg concentrations in glaucous gull (Larus hyperboreus) eggs decreased by 50% from 1993 to 2003 before starting to increase again. Glaucous gull eggs had the highest Hg concentrations followed by black guillemot eggs, and black-legged kittiwake eggs had the lowest concentrations consistently in the five years compared between 1993 and 2013. Based on published toxicological thresholds for Hg in eggs, there is little concern for adverse reproductive effects due to Hg exposure in these birds, although the levels in glaucous gull eggs warrant future scrutiny given the increase in Hg concentrations observed in recent years. There is evidence that the Hg trends observed reflect changing anthropogenic Hg emissions. It remains unclear, however, to what extent exposure to Hg on the overwintering grounds influences the Hg trends observed in the seabird eggs at Prince Leopold Island. Future research should focus on determining the extent to which Hg exposure on the breeding grounds versus the overwintering areas contribute to the trends observed in the eggs.

  14. Premature feather loss among common tern chicks in Ontario: the return of an enigmatic developmental anomaly

    PubMed Central

    Tyerman, Donald J.; Crump, Doug; Williams, Kim L.; Oswald, Stephen A.

    2016-01-01

    In July 2014, we observed premature feather loss (PFL) among non-sibling, common tern Sterna hirundo chicks between two and four weeks of age at Gull Island in northern Lake Ontario, Canada. Rarely observed in wild birds, to our knowledge PFL has not been recorded in terns since 1974, despite the subsequent banding of hundreds of thousands of tern chicks across North America alone. The prevalence, 5% of chicks (9/167), and extent of feather loss we report is more extreme than in previous reports for common terns but was not accompanied by other aberrant developmental or physical deformities. Complete feather loss from all body areas (wing, tail, head and body) occurred over a period of a few days but all affected chicks appeared vigorous and quickly began to grow replacement feathers. All but one chick (recovered dead and submitted for post-mortem) most likely fledged 10–20 days after normal fledging age. We found no evidence of feather dystrophy or concurrent developmental abnormalities unusual among affected chicks. Thus, the PFL we observed among common terns in 2014 was largely of unknown origin. There was striking temporal association between the onset of PFL and persistent strong southwesterly winds that caused extensive mixing of near-shore surface water with cool, deep lake waters. One hypothesis is that PFL may have been caused by unidentified pathogens or toxins welling up from these deep waters along the shoreline but current data are insufficient to test this. PFL was not observed among common terns at Gull Island in 2015, although we did observe similar feather loss in a herring gull Larus argentatus chick in that year. Comparison with sporadic records of PFL in other seabirds suggests that PFL may be a rare, but non-specific, response to a range of potential stressors. PFL is now known for gulls, penguins and terns. PMID:27231646

  15. Molecular characterization of novel circoviruses from finch and gull.

    PubMed

    Todd, D; Scott, A N J; Fringuelli, E; Shivraprasad, H L; Gavier-Widen, D; Smyth, J A

    2007-02-01

    The purpose of this study was to molecularly characterize circoviruses that infect finches and gulls. Circovirus-specific DNAs were isolated using polymerase chain reaction methods from bursa of Fabricius tissues from a Gouldian finch (Chloebia gouldiae) and a herring gull (Larus argentatus) that were known to be circovirus-infected. Nucleotide sequence determination and analysis of cloned genomic DNAs showed that these circoviruses represented novel members of the genus Circovirus of the family Circoviridae, and have been tentatively named Finch circovirus (FiCV) and Gull Circovirus (GuCV). Both new circoviruses shared genome organizational features with previously characterized circoviruses, such that both contained two major, inversely-arranged open reading frames encoding the putative replication-associated and capsid proteins, and both contained a potential stem-loop and nonanucleotide motif. Phylogenetic analyses based on genome nucleotide sequences and involving the seven additional genus members indicated that FiCV and GuCV were more closely related to canary circovirus, beak and feather disease virus and pigeon circovirus, and that FiCV and canary circovirus were the most closely related avian circoviruses. Pairwise comparisons showed that the capsid proteins of FiCV and GuCV shared highest amino acid identity values with those of canary circovirus (62.0%) and pigeon circovirus (40.6%), respectively. The 5' intergenic region of GuCV was longer (207 nucleotides) and contained more direct and inverse repeated sequences than those of other circoviruses, while the 3' intergenic region of FiCV was notable in being longer (307 nucleotides) than its counterparts in other circoviruses and in containing two long repeats of 77 nucleotides.

  16. Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.

    PubMed

    Anthony, Robert G; Estes, James A; Ricca, Mark A; Miles, A Keith; Forsman, Eric D

    2008-10-01

    Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993-1994 and 2000-2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993-1994 to 2000-2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex predator

  17. Concentrated nesting of mallards and gadwalls on Miller Lake Island, North Dakota

    USGS Publications Warehouse

    Duebbert, H.F.; Lokemoen, J.T.; Sharp, D.E.

    1983-01-01

    Island-nesting mallards (Anas platyrhynchos) and gadwalls (A. strepera) were studied on a 4.5-ha island in 385-ha Miller Lake in northwestern North Dakota during 1976-80. During the 5-year study, 2,561 duck nests of 9 species were found on Island A located 180 m offshore; 59% were mallard and 34% were gadwall. In patches of shrub cover, which contained the greatest concentrations of nests, densities ranged from 241 to 389 mallard nests/ha and from 139 to 237 gadwall nests/ha. Over 97% of the nests were placed in 4 patches of shrubs totaling about 1 ha of western snowberry (Symphoricarpos occidentalis)--Woods rose (Rosa woodsii) cover, which composed about 30% of the island's vegetation. Average hatching success was 85% for clutches of all species. Abandonment averaged 14% (348 of 2,426 nests) and was the major cause of egg failure. Only 15 nests (<1%) were destroyed, primarily by ring-billed (Larus delawarensis) or California gulls (L. californicus). A minimum of 15,960 ducklings including 9,300 mallards and 5,150 gadwalls hatched on 4.5-ha Island A. Hatching rates of eggs in successful nests averaged 83% for mallards and 87% for gadwalls. Despite the close spacing of nests, most individual hens maintained normal nesting regimes. Eighty-one percent of the mallard clutches contained 7-13 eggs and 81% of the gadwall clutches contained 8-14 eggs. Island A in Miller Lake provides an outstanding example of the potential for high reproduction levels of mallards and gadwalls nesting in small areas of predator-free habitats.

  18. The effects of heterospecifics and climatic conditions on incubation behavior within a mixed-species colony

    USGS Publications Warehouse

    Coates, Peter S.; Brussee, Brianne E.; Hothem, Roger L.; Howe, Kristy H.; Casazza, Michael L.; Eadie, John M.

    2016-01-01

    Parental incubation behavior largely influences nest survival, a critical demographic process in avian population dynamics, and behaviors vary across species with different life history breeding strategies. Although research has identified nest survival advantages of mixing colonies, behavioral mechanisms that might explain these effects is largely lacking. We examined parental incubation behavior using video-monitoring techniques on Alcatraz Island, California, of black-crowned night-heron Nycticorax nycticorax(hereinafter, night-heron) in a mixed-species colony with California gulls Larus californicus and western gulls L. occidentalis. We first quantified general nesting behaviors (i.e. incubation constancy, and nest attendance), and a suite of specific nesting behaviors (i.e. inactivity, vigilance, preening, and nest maintenance) with respect to six different daily time periods. We employed linear mixed effects models to investigate environmental and temporal factors as sources of variation in incubation constancy and nest attendance using 211 nest days across three nesting seasons (2010–2012). We found incubation constancy (percent of time on the eggs) and nest attendance (percent of time at the nest) were lower for nests that were located < 3 m from one or more gull nest, which indirectly supports the predator protection hypothesis, whereby heterospecifics provide protection allowing more time for foraging and other self-maintenance activities. To our knowledge, this is the first empirical evidence of the influence of one nesting species on the incubation behavior of another. We also identified distinct differences between incubation constancy and nest attentiveness, indicating that these biparental incubating species do not share similar energetic constraints as those that are observed for uniparental species. Additionally, we found that variation in incubation behavior was a function of temperature and precipitation, where the strength of these effects

  19. Unintended consequences of management actions in salt pond restoration: cascading effects in trophic interactions

    USGS Publications Warehouse

    Takekawa, John Y.; Ackerman, Joshua T.; Brand, Arriana; Graham, Tanya R.; Eagles-Smith, Collin A.; Herzog, Mark; Topping, Brent R.; Shellenbarger, Gregory; Kuwabara, James S.; Mruz, Eric; Piotter, Sara L.; Athearn, Nicole D.

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  20. Local and interannual variations in mercury and cadmium in eggs of eight seabird species of the Sinaloa coast, México.

    PubMed

    Ceyca, Juan P; Castillo-Guerrero, J Alfredo; García-Hernández, Jaqueline; Fernández, Guillermo; Betancourt-Lozano, Miguel

    2016-09-01

    Mercury (Hg) and cadmium (Cd) concentrations in eggs of 8 seabird species inhabiting 5 coastal ecosystems in Sinaloa, México were determined during 2 breeding seasons (2012 and 2013): blue-footed booby (Sula nebouxii), brown booby (Sula leucogaster), double-crested cormorant (Phalacrocorax auritus), magnificent frigatebird (Fregata magnificens), brown pelican (Pelecanus occidentalis), royal tern (Thalasseus maximus), laughing gull (Leucophaeus atricilla), and Heermann's gull (Larus heermanni). The interspecific differences found in the concentrations of both metals were attributed to the diet and foraging ecology of the species. The highest Hg concentrations were detected in piscivorous species (brown pelican, 0.42 µg/g; brown booby, 0.31 µg/g; blue-footed booby, 0.26 µg/g; and double-crested cormorant, 0.23 µg/g); whereas species with more varied diets presented the highest Cd concentrations (Heermann's gull, 0.31 µg/g; laughing gull, 0.27 µg/g; and magnificent frigatebird, 0.27 µg/g). Cadmium concentrations were significantly greater in 2013 than 2012 for most species, and brown pelican and laughing gull also had higher Hg concentrations in 2013 in Santa María Bay, suggesting a relationship as a result of the changes either in oceanographic conditions or in continental runoff. Mercury concentrations in brown pelican and Cd concentrations in Heermann's gull and laughing gull were above threshold levels for adverse effects on reproduction and survival. Environ Toxicol Chem 2016;35:2330-2338. © 2016 SETAC. © 2016 SETAC.

  1. Environmental Predictors of Seabird Wrecks in a Tropical Coastal Area

    PubMed Central

    Fulgencio de Moura, Jailson; Siciliano, Salvatore

    2016-01-01

    Beached bird surveys have been widely used to monitor the impact of oil pollution in the oceans. However, separating the combined effects of oil pollution, environmental variables and methodological aspects of beach monitoring on seabird stranding patterns is a challenging task. The effects of a comprehensive set of oceanographic and climatic variables and oil pollution on seabird strandings in a tropical area of Brazil were investigated herein, using two robust and innovative methods: Generalized Linear Mixed Models and Structural Equation Modeling. We assessed strandings of four resident seabird species along 480 km of beaches divided into 11 sampling areas, between November 2010 and September 2013. We found that increasing the distance from the nearest breeding island reduce the seabird stranding events. Storm activity and biological productivity were the most important factors affecting the stranding events of brown boobies Sula leucogaster, Cabot’s terns Thalasseus acuflavidus and kelp gulls Larus dominicanus. These species are also indirectly affected by warm tropical waters, which reduce chlorophyll-a concentrations. Beach surveys are, thus, useful to investigate the mortality rates of resident species near breeding sites, where individuals are more abundant and exposed to local factors associated with at-sea mortality. In contrast, conservation actions and monitoring programs for far-ranging seabird species are needed in more distant foraging areas. Furthermore, beach monitoring programs investigating the impact of oil pollution on seabirds need to account for the effects of environmental factors on stranding patterns. The present study also demonstrated that seabirds inhabiting tropical coastal waters are sensitive to climate conditions such as adverse weather, which are expected to increase in frequency and intensity in next decades. PMID:27992578

  2. Balancing Energy Budget in a Central-Place Forager: Which Habitat to Select in a Heterogeneous Environment?

    PubMed Central

    Patenaude-Monette, Martin; Bélisle, Marc; Giroux, Jean-François

    2014-01-01

    Foraging animals are influenced by the distribution of food resources and predation risk that both vary in space and time. These constraints likely shape trade-offs involving time, energy, nutrition, and predator avoidance leading to a sequence of locations visited by individuals. According to the marginal-value theorem (MVT), a central-place forager must either increase load size or energy content when foraging farther from their central place. Although such a decision rule has the potential to shape movement and habitat selection patterns, few studies have addressed the mechanisms underlying habitat use at the landscape scale. Our objective was therefore to determine how Ring-billed gulls (Larus delawarensis) select their foraging habitats while nesting in a colony located in a heterogeneous landscape. Based on locations obtained by fine-scale GPS tracking, we used resource selection functions (RSFs) and residence time analyses to identify habitats selected by gulls for foraging during the incubation and brood rearing periods. We then combined this information to gull survey data, feeding rates, stomach contents, and calorimetric analyses to assess potential trade-offs. Throughout the breeding season, gulls selected landfills and transhipment sites that provided higher mean energy intake than agricultural lands or riparian habitats. They used landfills located farther from the colony where no deterrence program had been implemented but avoided those located closer where deterrence measures took place. On the other hand, gulls selected intensively cultured lands located relatively close to the colony during incubation. The number of gulls was then greater in fields covered by bare soil and peaked during soil preparation and seed sowing, which greatly increase food availability. Breeding Ring-billed gulls thus select habitats according to both their foraging profitability and distance from their nest while accounting for predation risk. This supports the

  3. DNA barcoding of Dutch birds

    PubMed Central

    Aliabadian, Mansour; Beentjes, Kevin K.; Roselaar, C.S. (Kees); van Brandwijk, Hans; Nijman, Vincent; Vonk, Ronald

    2013-01-01

    Abstract The mitochondrial cytochrome c oxidase subunit I (COI) can serve as a fast and accurate marker for the identification of animal species, and has been applied in a number of studies on birds. We here sequenced the COI gene for 387 individuals of 147 species of birds from the Netherlands, with 83 species being represented by > 2 sequences. The Netherlands occupies a small geographic area and 95% of all samples were collected within a 50 km radius from one another. The intraspecific divergences averaged 0.29% among this assemblage, but most values were lower; the interspecific divergences averaged 9.54%. In all, 95% of species were represented by a unique barcode, with 6 species of gulls and skua (Larus and Stercorarius) having at least one shared barcode. This is best explained by these species representing recent radiations with ongoing hybridization. In contrast, one species, the Lesser Whitethroat Sylvia curruca showed deep divergences, averaging 5.76% and up to 8.68% between individuals. These possibly represent two distinct taxa, S. curruca and S. blythi, both clearly separated in a haplotype network analysis. Our study adds to a growing body of DNA barcodes that have become available for birds, and shows that a DNA barcoding approach enables to identify known Dutch bird species with a very high resolution. In addition some species were flagged up for further detailed taxonomic investigation, illustrating that even in ornithologically well-known areas such as the Netherlands, more is to be learned about the birds that are present. PMID:24453549

  4. A nonlethal microsampling technique to monitor the effects of mercury on wild bird eggs.

    PubMed

    Stebbins, Katherine R; Klimstra, Jon D; Eagles-Smith, Collin A; Ackerman, Joshua T; Heinz, Gary H

    2009-03-01

    Methylmercury is the predominant chemical form of mercury reported in the eggs of wild birds, and the embryo is the most sensitive life stage to methylmercury toxicity. Protective guidelines have been based mainly on captive-breeding studies with chickens (Gallus gallus), mallards (Anas platyrhynchos), and ring-necked pheasants (Phasianus colchicus) or on field studies where whole eggs were collected and analyzed and the effects of the mercury were measured based on the reproductive success of the remaining eggs. However, both of these methods have limitations. As an alternative, we developed a technique that involves extracting a small sample of albumen from a live egg, sealing the egg, returning the egg to its nest to be naturally incubated by the parents, and then relating the hatching success of this microsampled egg to its mercury concentration. After first developing this technique in the laboratory using chicken and mallard eggs, we selected the laughing gull (Larus atricilla) and black-necked stilt (Himantopus mexicanus) as test subjects in the field. We found that 92% of the microsampled laughing gull eggs met our reproductive endpoint of survival to the beginning of hatching compared to 100% for the paired control eggs within the same nests. Microsampled black-necked stilt eggs exhibited 100% hatching success compared to 93% for the paired control eggs. Our results indicate that microsampling is an effective tool for nonlethally sampling mercury concentrations in eggs and, as such, can be used for monitoring sensitive species, as well as for improving studies that examine the effects of mercury on avian reproduction.

  5. Effects of Perfluoroalkyl Compounds on mRNA Expression Levels of Thyroid Hormone-Responsive Genes in Primary Cultures of Avian Neuronal Cells

    PubMed Central

    Vongphachan, Viengtha; Cassone, Cristina G.; Wu, Dongmei; Chiu, Suzanne; Crump, Doug; Kennedy, Sean W.

    2011-01-01

    There is growing interest in assessing the neurotoxic and endocrine disrupting potential of perfluoroalkyl compounds (PFCs). Several studies have reported in vitro and in vivo effects related to neuronal development, neural cell differentiation, prenatal and postnatal development and behavior. PFC exposure altered hormone levels and the expression of hormone-responsive genes in mammalian and aquatic species. This study is the first to assess the effects of PFCs on messenger RNA (mRNA) expression in primary cultures of neuronal cells in two avian species: the domestic chicken (Gallus domesticus) and herring gull (Larus argentatus). The following thyroid hormone (TH)–responsive genes were examined using real-time reverse transcription-PCR: type II iodothyronine 5′-deiodinase (D2), D3, transthyretin (TTR), neurogranin (RC3), octamer motif–binding factor (Oct-1), and myelin basic protein. Several PFCs altered the mRNA expression levels of genes associated with the TH pathway in avian neuronal cells. Short-chained PFCs (less than eight carbons) altered the expression of TH-responsive genes (D2, D3, TTR, and RC3) in chicken embryonic neuronal cells to a greater extent than long-chained PFCs (more than or equal to eight carbons). Variable transcriptional changes were observed in herring gull embryonic neuronal cells exposed to short-chained PFCs; mRNA levels of Oct-1 and RC3 were upregulated. This is the first study to report that PFC exposure alters mRNA expression in primary cultures of avian neuronal cells and may provide insight into the possible mechanisms of action of PFCs in the avian brain. PMID:21212296

  6. Diets of aquatic birds reflect changes in the Lake Huron ecosystem

    USGS Publications Warehouse

    Hebert, Craig E.; Weseloh, D.V. Chip; Idrissi, Abode; Arts, Michael T.; Roseman, Edward F.

    2009-01-01

    Human activities have affected the Lake Huron ecosystem, in part, through alterations in the structure and function of its food webs. Insights into the nature of food web change and its ecological ramifications can be obtained through the monitoring of high trophic level predators such as aquatic birds. Often, food web change involves alterations in the relative abundance of constituent species and/or the introduction of new species (exotic invaders). Diet composition of aquatic birds is influenced, in part, by relative prey availability and therefore is a sensitive measure of food web structure. Using bird diet data to make inferences regarding food web change requires consistent measures of diet composition through time. This can be accomplished by measuring stable chemical and/or biochemical “ecological tracers” in archived avian samples. Such tracers provide insights into pathways of energy and nutrient transfer. In this study, we examine the utility of two groups of naturally-occurring intrinsic tracers (stable isotopes and fatty acids) to provide such information in a predatory seabird, the herring gull (Larus argentatus). Retrospective stable nitrogen and carbon isotope analysis of archived herring gull eggs identified declines in gull trophic position and shifts in food sources in Lake Huron over the last 25 years and changes in gull diet composition were inferred from egg fatty acid patterns. These independent groups of ecological tracers provided corroborating evidence of dietary change in this high trophic level predator. Gull dietary shifts were related to declines in prey fish abundance which suggests large-scale alterations to the Lake Huron ecosystem. Dietary shifts in herring gulls may be contributing to reductions in resources available for egg formation. Further research is required to evaluate how changes in resource availability may affect population sustainability in herring gulls and other waterbird species. Long-term biological monitoring

  7. The role of prezygotic isolation mechanisms in the divergence of two parasite species.

    PubMed

    Henrich, Tina; Kalbe, Martin

    2016-11-09

    The formation of reproductive barriers in diverging lineages is a prerequisite to complete speciation according to the biological species concept. In parasites with complex life cycles, speciation may be driven by adaptation to different intermediate hosts, yet diverging lineages can still share the same definitive host where reproduction takes place. In these cases, prezygotic isolation mechanisms should evolve very early and be particularly strong, preventing costly unfavourable matings. In this study, we investigated the importance of prezygotic barriers to reproduction in two cestode species that diverged 20-25mya and show an extraordinary degree of specificity to different intermediate hosts. Both species share the same definitive hosts and hybridize in the laboratory. Yet, natural hybrids have so far not been detected. We used a combination of different experiments to investigate the role of prezygotic barriers to reproduction in the speciation of these parasites. First, we investigated whether hybridization is possible under natural conditions by exposing lab-reared herring gulls (Larus argentatus, the definitive hosts) to both parasites of either sympatric or allopatric combinations. In a second experiment, we tested whether the parasites prefer conspecifics over parasites from a different species in dichotomous mate choice trials. Our results show that the two species hybridize under natural conditions with parasites originating either from sympatric or allopatric populations producing hybrid offspring. Surprisingly, the mate choice experiment indicated that both parasite species prefer mates of the different species to conspecifics. Neither fundamental constraints against hybridization in a natural host nor assortative mate choice sufficiently explain the persistent segregation of the two tapeworm species in nature. Hence, postzygotic ecological selection against hybrids is presumably the more important driving force limiting gene flow between the two

  8. The identification of a new Giardia duodenalis assemblage in marine vertebrates and a preliminary analysis of G. duodenalis population biology in marine systems.

    PubMed

    Lasek-Nesselquist, Erica; Welch, David Mark; Sogin, Mitchell L

    2010-08-01

    Giardia duodenalis is an intestinal parasite of many vertebrates. The presence of G. duodenalis in the marine environment due to anthropogenic and wildlife activity is well documented, including the contributions from untreated sewage and storm water, agricultural run-off and droppings from terrestrial animals. Recently, studies have detected this protistan parasite in the faeces of marine vertebrates such as whales, dolphins, seals and shore birds. To explore the population biology of G. duodenalis in marine life, we determined the prevalence of G. duodenalis in two species of seal (Halichoerus grypus, Phoca vitulina vitulina and Phoca vitulina richardsi) from the east and west coasts of the USA, sequenced two loci from G. duodenalis-positive samples to assess molecular diversity and examined G. duodenalis distribution amongst these seals and other marine vertebrates along the east coast. We found a significant difference in the presence of G. duodenalis between east and west coast seal species. Only the zoonotic lineages of G. duodenalis, Assemblages A and B and a novel lineage, which we designated as Assemblage H, were identified in marine vertebrates. Assemblages A and B are broadly distributed geographically and show a lack of host specificity. Only grey seal (Halichoerus grypus) samples and one gull sample (Larus argentatus) from a northern location of Cape Cod, Massachusetts, USA, showed the presence of Assemblage H haplotypes; only one other study of harbour seals from the Puget Sound region of Washington, USA previously recorded the presence of an Assemblage H haplotype. Assemblage H sequences form a monophyletic clade that appears as divergent from the other seven Assemblages of G. duodenalis as these assemblages are from each other. The discovery of a previously uncharacterised lineage of G. duodenalis suggests that this parasite has more genetic diversity and perhaps a larger host range than previously believed.

  9. Avian influenza and animal health risk: conservation of endemic threatened wild birds in Sardinia Island.

    PubMed

    Delogu, Mauro; Piredda, Isabella; Pintore, Antonio; Cabras, Pierangela; Cotti, Claudia; Ghetti, Giulia; Raffini, Elisabetta; De Marco, Maria A

    2012-12-01

    Sardinia is a Mediterranean island with a long geological history, leading to a separation process from continental Europe during the Miocene. As a consequence, in this insular habitat some wild bird species developed endemic forms, some of which are currently threatened. The aim of this study is to evaluate the possible animal health risk associated with a potential avian influenza virus (AIV) circulation in Sardinian wild bird populations. Overall, 147 cloacal swabs were sampled in the Sardinia region from June 2009 to September 2011. Samples were obtained from 12 taxonomic orders, including 16 families and 40 species of birds. Based on the endangered host status or on the ecology of the host-virus interaction, samples were categorized into three groups of species: 1) endemic, endangered, or both (17 species); 2) potential reservoir (21 species); and 3) potential spillover (two species). Cloacal swabs were tested by reverse transcription (RT)-PCR for influenza A virus matrix gene amplification. Forty-one serum samples were tested by nucleoprotein-enzyme-linked immunosorbent assay (NP-ELISA) for antibodies against influenza A virus nucleoprotein and by hemagglutination inhibition assay for detection of seropositivity against H5 and H7 AIV subtypes. No cloacal swabs tested RT-PCR positive for AIV, whereas two weak seropositive results were detected by NP-ELISA in a mallard (Anas platyrhynchos) and in a yellow-legged gull (Larus michahellis). The low or absent AIV circulation detected in Sardinia's wild birds during the study suggests a naïve status in these avian populations. These data provide new information on AIV circulation in Sardinia's wild birds that could be applied to implement conservation strategies for threatened species.

  10. Population control of an overabundant species achieved through consecutive anthropogenic perturbations.

    PubMed

    Payo-Payo, Ana; Oro, Daniel; Igual, José Manuel; Jover, Lluis; Sanpera, Carolina; Tavecchia, Giacomo

    2015-12-01

    The control of overabundant vertebrates is often problematic. Much work has focused on population-level responses and overabundance due to anthropogenic subsidies. However, far less work has been directed at investigating responses following the removal of subsidies. We investigate the consequences of two consecutive perturbations, the closure of a landfill and an inadvertent poisoning event, on the trophic ecology (δ13C, δ15N, and δ34S), survival, and population size of an overabundant generalist seabird species, the Yellow-legged Gull (Larus michahellis). We expected that the landfill closure would cause a strong dietary shift and the inadvertent poisoning a decrease in gull population size. As a long-lived species, we also anticipated adult survival to be buffered against the decrease in food availability but not against the inadvertent poisoning event. Stable isotope analysis confirmed the dietary shift towards marine resources after the disappearance of the landfill. Although the survival model was inconclusive, it did suggest that the perturbations had a negative effect on survival, which was followed by a recovery back to average values. Food limitation likely triggered dispersal to other populations, while poisoning may have increased mortality; these two processes were likely responsible for the large fall in population size that occurred after the two consecutive perturbations. Life-history theory suggests that perturbations may encourage species to halt existing breeding investment in order to ensure future survival. However, under strong perturbation pulses the resilience threshold might be surpassed and changes in population density can arise. Consecutive perturbations may effectively manage overabundant species.

  11. Relationships between polybrominated diphenyl ethers and transcription and activity of type 1 deiodinase in a gull highly exposed to flame retardants.

    PubMed

    François, Anthony; Técher, Romy; Houde, Magali; Spear, Philip; Verreault, Jonathan

    2016-09-01

    Deca-brominated diphenyl ether (deca-BDE), composed mainly of BDE-209, is subject to usage restrictions in North America and Europe, although global action on its continued use has yet to be undertaken. Relatively large concentrations of polybrominated diphenyl ethers (PBDEs), especially BDE-209 and its higher brominated degradation products, have been reported in tissues of ring-billed gulls (Larus delawarensis) breeding near the densely populated city of Montreal (QC, Canada). There is limited knowledge of BDE-209 biotransformation and toxicokinetics in birds. Deiodinases, a class of enzymes catalyzing thyroid hormone conversion, have been suggested to be involved in BDE-209 debromination in birds. The objective of the present study was to investigate the relationships between PBDE concentrations and type 1 deiodinase (D1) transcription and in vitro activity (microsomes) in livers of Montreal-breeding ring-billed gulls. The ring-billed gulls exhibiting the highest D1 activity in liver microsomes accumulated the greatest liver concentrations of hepta-BDEs and octa-BDEs. Activity of D1 was inversely related to concentration ratios of BDE-209 to octa-BDEs and ∑hepta-BDE. An even stronger inverse relation was found between D1 activity and BDE-209 to ∑nona + octa + hepta-BDE concentration ratios. The messenger ribonucleic acid (mRNA) levels of D1 in gull livers were inversely associated with liver concentrations of ∑octa-BDE. The present study's findings suggest that D1 is potentially involved in BDE-209 biotransformation and accumulation of higher brominated PBDEs in livers of ring-billed gulls. Environ Toxicol Chem 2016;35:2215-2222. © 2016 SETAC.

  12. Associations between organohalogen concentrations and transcription of thyroid-related genes in a highly contaminated gull population.

    PubMed

    Técher, Romy; Houde, Magali; Verreault, Jonathan

    2016-03-01

    A number of studies have reported altered circulating thyroid hormone levels in birds exposed either in controlled settings or in their natural habitat to ubiquitous organohalogen compounds including organochlorines (OCs) and polybrominated diphenyl ether (PBDE) flame retardants. However, limited attention has been paid to underlying homeostatic mechanisms in wild birds such as changes in the expression of genes in the hypothalamic-pituitary-thyroid (HPT) axis. The objective of the present study was to investigate the relationships between hepatic concentrations of major organohalogens (PBDEs and OCs), and circulating thyroid hormone (free and total thyroxine (T4) and triiodothyronine (T3)) levels and transcription of 14 thyroid-related genes in three tissues (thyroid, brain, and liver) of an urban-adapted bird exposed to high organohalogen concentrations in the Montreal area (QC, Canada), the ring-billed gull (Larus delawarensis). Positive correlations were found between liver concentrations of several polychlorinated biphenyls (PCBs), PBDEs as well as chlordanes and total plasma T4 levels. Hepatic concentrations of several PBDEs were negatively correlated with mRNA levels of deiodinase type 3, thyroid peroxidase, and thyroid hormone receptor β (TRβ) in the thyroid gland. Liver PCB (deca-CB) correlated positively with mRNA levels of sodium-iodide symporter and TRα. In brain, concentrations of most PBDEs were positively correlated with mRNA levels of organic anion transporter protein 1C1 and transthyretin, while PCBs positively correlated with expression of TRα and TRβ as well as deiodinase type 2. These multiple correlative linkages suggest that organohalogens operate through several mechanisms (direct or compensatory) involving gene transcription, thus potentially perturbing the HPT axis of this highly organohalogen-contaminated ring-billed gull population.

  13. Is the bone tissue of ring-billed gulls breeding in a pollution hotspot in the St. Lawrence River, Canada, impacted by halogenated flame retardant exposure?

    PubMed

    Plourde, Stéphanie Pellerin; Moreau, Robert; Letcher, Robert J; Verreault, Jonathan

    2013-11-01

    Bone metabolism is a tightly regulated process that controls bone remodeling and repair in addition to maintaining circulating calcium and phosphate levels. It has been shown that certain organohalogen contaminants may adversely impact bone tissue metabolism and structure in wildlife species. However, exceedingly few studies have addressed the bone-related effects of organohalogen exposure in birds. The objective of the present study was to investigate the associations between markers of bone metabolism and structural integrity, and concentrations of established and current-use halogenated flame retardants (FRs) in ring-billed gulls (Larus delawarensis) nesting in a known FR hotspot area in the St. Lawrence River (Montreal, Canada). Bone metabolism was assessed using plasma calcium and inorganic phosphate levels, and alkaline phophatase activity, while bone (tarsus; trabecular and cortical sections) structure quality was examined using the percentage of bone tissue comprised in the total bone volume (Bv/Tv) and bone mineral density (BMD). Bv/Tv and BMD of the tarsus tended (not significant) to be positively associated with circulating calcium levels in male ring-billed gulls. Moreover, concentrations of FRs in male bird liver (brominated diphenyl ether (BDE)-154, -183, -201, and -209) and plasma (BDE-209) were negatively correlated with trabecular and cortical BMD of the tarsus. These correlative associations may suggest light demineralization of bone tissue associated with FR exposure in male ring-billed gulls. Present findings provide some evidence that bone (tarsus) metabolism and mineral composition may be impacted in high FR-exposed (mainly to PBDEs) ring-billed gulls breeding in the highly urbanized Montreal region.

  14. In vitro biotransformation of decabromodiphenyl ether (BDE-209) and Dechlorane Plus flame retardants: a case study of ring-billed gull breeding in a pollution hotspot in the St. Lawrence River, Canada.

    PubMed

    Chabot-Giguère, Bernice; Letcher, Robert J; Verreault, Jonathan

    2013-05-01

    Decabromodiphenyl ether (deca-BDE) mixture (~97% of BDE-209) is now facing usage restrictions worldwide, which is leading to increased utilization of a series of alternative, replacement flame retardant (FR) products. Among these, Dechlorane Plus (DP) is receiving growing attention as this FR is increasingly being detected in wildlife samples, including birds from North America, Europe and Asia. Recent survey conducted in a known FR hotspot in the St. Lawrence River basin near Montreal (QC, Canada) revealed unexpectedly high detection frequencies and concentrations of BDE-209 and DP isomers (syn- and anti-DP) in the liver of breeding ring-billed gulls (Larus delawarensis) (RBGUs). Despite the global distribution of these current-use FRs, there is to our knowledge no study that has addressed the in vitro biotransformation of BDE-209 and DP isomers in birds. This study aimed at understanding the in vitro metabolism of BDE-209 and syn- and anti-DP using liver microsomes of Montreal-breeding RBGUs. Although BDE-15 (positive assay control) was consistently and positively depleted over the 90-min time frame of the in vitro assay, no depletion was observed for BDE-209 and DP isomers. These results suggest that CYP isoenzyme-mediated reductive dehalogenation of BDE-209 and DP is not likely to be a substantial metabolic pathway in RBGUs. However, investigations on deiodinases (expression, activity) should be considered in future studies as these enzymes have been suggested to be involved in the sequential debromination of BDE-209 in fish and human studies. High levels of BDE-209 determined in liver of RBGUs that strongly correlated with those of known or suggested BDE-209 debromination products (hepta- through nona-BDEs) may thus be indicative of concomitant dietary (e.g., fish consumption) and environmental exposure in the greater Montreal area, combined with poor or lack of metabolic capability toward these FRs.

  15. Short-term fasts increase levels of halogenated flame retardants in tissues of a wild incubating bird.

    PubMed

    Marteinson, Sarah C; Drouillard, Ken G; Verreault, Jonathan

    2016-04-01

    Many species are adapted for fasting during parts of their life cycle. For species undergoing extreme fasts, lipid stores are mobilized and accumulated contaminants can be released to exert toxicological effects. However, it is unknown if short-term fasting events may have a similar effect. The objective of this study was to determine if short successive fasts are related to contaminant levels in liver and plasma of birds. In ring-billed gulls (Larus delawarensis), both members of the pair alternate between incubating the nest for several hours (during which they fast) and foraging, making them a useful model for examining this question. Birds were equipped with miniature data loggers recording time and GPS position for two days to determine the proportion and duration of time birds spent in these two activities. Liver and plasma samples were collected, and halogenated flame retardants (HFRs) (PBDEs and dechlorane plus) and organochlorines (OCs) (PCBs, DDTs, and chlordane-related compounds) were determined. Most birds (79%) exhibited plasma lipid content below 1%, indicating a likely fasted state, and plasma lipid percent declined with the number of hours spent at the nest site. The more time birds spent at their nest site, the higher were their plasma and liver concentrations of HFRs. However, body condition indices were unrelated to either the amount of time birds fasted at the nest site or contaminant levels, suggesting that lipid mobilization might not have been severe enough to affect overall body condition of birds and to explain the relationship between fasting and HFR concentrations. A similar relationship between fasting and OC levels was not observed, suggesting that different factors are affecting short-term temporal variations in concentrations of these two classes of contaminants. This study demonstrates that short fasts can be related to increased internal contaminant exposure in birds and that this may be a confounding factor in research and

  16. Oil pollution increases plasma antioxidants but reduces coloration in a seabird.

    PubMed

    Pérez, Cristóbal; Lores, Marta; Velando, Alberto

    2010-08-01

    It has been suggested that condition-dependent signals may be a useful measure of environmental quality. In this study, we tested the hypothesis that oil pollution enhances oxidative stress and impairs expression of a carotenoid-based signal in a wild population of the yellow-legged gull (Larus michahellis). During the courtship period, a group of gulls were fed a supplementary diet containing heavy fuel oil from the Prestige oil spill and were compared with control gulls fed a similar supplementary diet without fuel oil. Blood levels of polycyclic aromatic hydrocarbons, the most toxic components of crude oils, were higher (30%) in the Prestige oil-fed gulls than in the control gulls. Plasma concentrations of vitamin E and carotenoids were also significantly higher in the Prestige oil-fed gulls (31 and 27%, respectively). Although, the plasma levels of lipid peroxidation markers were higher (13%) in gulls fed with Prestige oil than in the control gulls, these differences were not significant, possibly because of the small number of gulls analyzed. The red bill spot was significantly smaller (16%) in the oil-fed gulls than in the control individuals. This study provides the first experimental evidence that a carotenoid-based signal in a free-living seabird is affected by exposure to oil pollution and is hence indicative of environmental quality. Since the yellow-legged gull belongs to a complex of species widely distributed throughout the northern hemisphere, the method described may constitute a useful tool for evaluating sub-lethal effects of oil spills in seabirds.

  17. Pacific Continental Shelf Environmental Assessment (PaCSEA): aerial seabird and marine mammal surveys off northern California, Oregon, and Washington, 2011-2012

    USGS Publications Warehouse

    Adams, Josh; Felis, Jonathan J.; Mason, John W.; Takekawa, John Y.

    2014-01-01

    counted (19,033) with Common Murres (Uria aalge) representing the majority of individuals counted (70.4% of total). The remaining six most abundant taxa included: Surf/White-winged Scoters (Melanitta perspicillata/M. fusca; 4.8% of total), Herring/Thayer’s Gulls (Larus argentatus/L. thayeri; 3.8% of total), Cassin’s Auklets (Ptychoramphus aleuticus; 3.8% of total), Glaucous-winged Gulls (Larus glaucescens; 3.7% of total), Black-legged Kittiwakes (Rissa tridactyla; 2.0% of total), and Western Gulls (Larus occidentalis; 1.9% of total). During summer, five species comprised >95% of the total number of birds counted (17,063) with the majority comprised of Common Murres (54.1% of total) and Sooty Shearwaters (Puffinus griseus; 34.4% of total). The remaining most abundant three taxa included: Fork-tailed Storm-Petrels (Oceanodroma furcata; 3.3% of total), Western Gulls (2.1% of total), and Leach’s Storm-Petrels (Oceanodroma leucorhoa; 1.1% of total). During fall, nine species comprised >85% of the total number of birds counted (23,376) with the majority comprised of Common Murres (50.0% of total) and Sooty Shearwaters (10.5% of total). The remaining seven taxa included Cassin’s Auklets (5.2% of total), Surf/White-winged Scoters (5.1% of total), Fork-tailed Storm-Petrels (3.8% of total), Red/Red-necked Phalaropes (Phalaropus fulicarius/P. lobatus; 3.2% of total), California Gulls (Larus californicus; 3.1% of total), Northern Fulmars (Fulmarus glacialis; 2.7% of total), and Sabine’s Gulls (Xema sabini; 2.2% of total). Throughout the entire PaCSEA survey area, average densities (± SE) at sea for all marine birds combined were similar between fall (23.7 ± 1.9 birds km-2) and winter (24.0 ± 1.9 birds km-2) and least during summer (16.3 ± 2.2 birds km-2). Marine bird densities at sea varied according to bathymetric domain and season. Throughout the entire PaCSEA study area average densities (± SE) for all marine birds combined were greatest over the inner-shelf domain

  18. Breeding productivity of Smith Island black ducks

    USGS Publications Warehouse

    Haramis, G.M.; Jorde, Dennis G.; Olsen, G.H.; Stotts, D.B.; Harrison, M.K.; Perry, M.C.

    2002-01-01

    We investigated the breeding performance of American black ducks (Anas rubripes) on Smith Island, Chesapeake Bay, to improve our understanding of island black duck breeding ecology and to make management recommendations to enhance productivity. During 1995-96, we implanted 56 female black ducks with 20-g radio transmitters and tracked 35 of the individuals through the breeding season to locate nests, determine nest fate, and identify brood habitat. We also increased preseason banding efforts and compared capture characteristics over 12 years with those from the Deal Island Wildlife Management Area, a banding site on the mainland of Tangier Sound. A low rate of nesting (37%), lack of renesting, and poor hatching success (31%) indicated that island salt marsh habitats present a harsh environment for breeding black ducks. Black ducks located 11 of 13 nests (85%) in black needlerush (Juncus roemerianus) marsh where they were vulnerable to flooding from extreme tides and to egg predators. No nests were found on forested tree hammocks, a feature that distinguishes Smith Island from nearby South Marsh and Bloodsworth Islands. Nest predators included red foxes (Vulpes vulpes), herring gulls (Larus argentams), fish crows (Corvus ossifragus), and, potentially, Norway rats (Rattus norvegicus). Unlike mainland red foxes, foxes radio tracked on Smith Island were found to be capable swimmers and effective low marsh predators. We found shoreline meadows of widgeon grass (Ruppia maritima) to be important foraging sites for black ducks and suspected that the virtual absence of fresh water in this high salinity environment (1217+ ppt) to incur some cost in terms of growth and survival of ducklings. Preseason bandings revealed a high proportion of banded adults and a strong positive correlation in age ratios with the Deal Island banding site. This latter finding strongly suggests a negative universal effect of storm tides on nest success for Tangier Sound black ducks. Management to

  19. Toxicity of ingested crude petroleum oil to marine birds: pathology and pathogenesis

    SciTech Connect

    Leighton, F.A.

    1984-01-01

    A series of experiments was carried out to identify toxic effects of ingested Prudhoe Bay crude oil in nestling herring gulls (Larus argentatus) and Atlantic puffins (Fratercula arctica). Wild-caught birds were brought to the laboratory, maintained on a marine diet and given oral doses of oil. Initial results identified anemia as a toxic effect of oil ingestion and subsequent experiments focussed on the erythron as a target tissue. Hemolytic anemia with Heinz bodies in red blood cells ocurred in gulls and puffins that ingested greater than or equal to 10 ml oil per kg per day for 4-5 days. Anemia developed precipitously as a hemolytic crisis. Structural lesions in red cells included Heinz body formation, anisocytosis, severe distortions of cell shape, plasma membrane crenulation, mineralization of mitochondria, formation of abnormal cytoplasmic vesicles, and both abnormally high and abnormally low cytoplasmic density. These data permitted correlative evaluation of ultrastructural and biochemical changes in red cells experiencing oxidant stress due to oil ingestion. Several other lesions occurred on both oil-dosed and control birds but were significantly more prevalent in the former. These lesions were focal adrenal necrosis, depletion of adrenal lipid, depletion of lymphocytes in thymus and bursa of Fabricius, and virus infection of the bursa of Fabricius. These latter lesions suggested immunosuppression in oil-dosed birds. In a pilot study, oral doses of disulfiram prevented the usual induction of hepatic mixed-function oxidases caused by ingestion of oil by gulls, and also prevented development of Heinz bodies and of increased GSH in red cells of gulls given large oral doses of oil.

  20. Bathing birds bias beta-diversity: frequent dispersal by gulls homogenizes fauna in a rock-pool metacommunity.

    PubMed

    Simonis, Joseph L; Ellis, Julie C

    2014-06-01

    Metacommunity theory generally predicts that regional dispersal of organisms among local habitat patches should influence spatial patterns of species diversity. In particular, increased dispersal rates are generally expected to increase local (alpha) diversity, yet homogenize local communities across the region (decreasing beta-diversity), resulting in no change in regional (gamma) diversity. Although the effect of dispersal on alpha-diversity has garnered much experimental attention, the influence of dispersal rates on diversity at larger spatial scales (beta and gamma) is poorly understood. Furthermore, these theoretical predictions are not well tested in the field, where other environmental factors (e.g., habitat size, resource density) likely also influence species diversity. Here, we used a system of freshwater rock pools on Appledore Island, Maine, USA, to test the effects of dispersal rate on species diversity in metacommunities. The pools exist in clusters (metacommunities) that experience different levels of dispersal imposed by gulls (Larus spp.), which we show to be frequent passive dispersers of rock-pool invertebrates. Although previous research has suggested that waterbirds may disperse aquatic invertebrates, our study is the first to quantify the rate at which such dispersal occurs and determine its effects on species diversity. In accordance with theory, we found that metacommunities experiencing higher dispersal rates had significantly more homogeneous local communities (reduced beta-diversity) and that gamma-diversity was not influenced by dispersal rate. Contrary to theoretical predictions, however, alpha-diversity in the rock pools was not significantly influenced by dispersal. Rather, local diversity was significantly positively related to local habitat size, and both alpha- and gamma-diversity were influenced by the physicochemical environment of the pools. These results provide an important field test of metacommunity theory, highlighting how

  1. Environmental Predictors of Seabird Wrecks in a Tropical Coastal Area.

    PubMed

    Tavares, Davi Castro; Fulgencio de Moura, Jailson; Siciliano, Salvatore

    2016-01-01

    Beached bird surveys have been widely used to monitor the impact of oil pollution in the oceans. However, separating the combined effects of oil pollution, environmental variables and methodological aspects of beach monitoring on seabird stranding patterns is a challenging task. The effects of a comprehensive set of oceanographic and climatic variables and oil pollution on seabird strandings in a tropical area of Brazil were investigated herein, using two robust and innovative methods: Generalized Linear Mixed Models and Structural Equation Modeling. We assessed strandings of four resident seabird species along 480 km of beaches divided into 11 sampling areas, between November 2010 and September 2013. We found that increasing the distance from the nearest breeding island reduce the seabird stranding events. Storm activity and biological productivity were the most important factors affecting the stranding events of brown boobies Sula leucogaster, Cabot's terns Thalasseus acuflavidus and kelp gulls Larus dominicanus. These species are also indirectly affected by warm tropical waters, which reduce chlorophyll-a concentrations. Beach surveys are, thus, useful to investigate the mortality rates of resident species near breeding sites, where individuals are more abundant and exposed to local factors associated with at-sea mortality. In contrast, conservation actions and monitoring programs for far-ranging seabird species are needed in more distant foraging areas. Furthermore, beach monitoring programs investigating the impact of oil pollution on seabirds need to account for the effects of environmental factors on stranding patterns. The present study also demonstrated that seabirds inhabiting tropical coastal waters are sensitive to climate conditions such as adverse weather, which are expected to increase in frequency and intensity in next decades.

  2. Parrot bornavirus-2 and -4 RNA detected in wild bird samples in Japan are phylogenetically adjacent to those found in pet birds in Japan.

    PubMed

    Sassa, Yukiko; Bui, Vuong Nghia; Saitoh, Keisuke; Watanabe, Yukiko; Koyama, Satoshi; Endoh, Daiji; Horie, Masayuki; Tomonaga, Keizo; Furuya, Tetsuya; Nagai, Makoto; Omatsu, Tsutomu; Imai, Kunitoshi; Ogawa, Haruko; Mizutani, Tetsuya

    2015-10-01

    Bornaviruses (family Bornaviridae) are non-segmented negative-strand RNA viruses. Avian bornaviruses (ABVs), which are causative agents of proventricular dilatation disease, are a genetically diverse group with at least 15 genotypes, including parrot bornaviruses (PaBVs) and aquatic bird bornavirus 1(ABBV-1). Borna disease virus 1(BoDV-1), which infects mammals and causes neurological diseases, has also been reported to infect avian species, although the numbers of the cases have been markedly fewer than those of ABVs. In this study, we conducted genetic surveillance to detect ABVs (PaBV-1 to -5 and ABBV-1) and BoDV-1 in wild birds in Japan. A total of 2078 fecal or cloacal swab samples were collected from wild birds in 2006, 2007, 2008, and 2011, in two regions of Japan. The results demonstrated the presence of PaBV-2 and -4 RNA, while no positive results for other PaBVs, ABBV-1, and BoDV-1 were obtained. PaBV-2 and -4 RNA were detected in 18 samples (0.9 %) of the genera Anas, Grus, Larus, Calidris, Haliaeetus, and Emberiza, in which either PaBV-2 RNA or PaBV-4 RNA, or both PaBV-2 and -4 RNA were detected in 15 (0.7 %), 5 (0.2 %), and 2 (0.1 %) samples, respectively. The nucleotide sequences of PaBV-2 and -4 detected in these samples from wild birds are phylogenetically close to those found in samples from pet birds in Japan, with identities ranging from 99.8 to 100 % and from 98.2 to 99.4 %, respectively. To the best of our knowledge, this is the first report on the detection of PaBV-2 and -4 RNA detected in samples from wild birds.

  3. Antioxidants and embryo phenotype: is there experimental evidence for strong integration of the antioxidant system?

    PubMed

    Possenti, Cristina Daniela; Karadas, Filiz; Colombo, Graziano; Caprioli, Manuela; Rubolini, Diego; Milzani, Aldo; Donne, Isabella Dalle; Saino, Nicola; Parolini, Marco

    2017-02-15

    Organisms have evolved complex defense systems against oxidative stress. Bird eggs contain maternally derived antioxidants that protect embryos from oxidative damage. The antioxidant system components are thought to be integrated, but few studies have analyzed the covariation between antioxidant concentrations, embryo 'oxidative status' and morphology. In addition, no study has tested the effects of experimental change in yolk antioxidant concentration on other antioxidants, on their reciprocal relationships and on their relationships with embryo oxidative status or growth, which are expected if antioxidants defenses are integrated. In yellow-legged gull (Larus michahellis) embryos, we analyzed the covariation between several antioxidants, markers of 'oxidative status' [total antioxidant capacity (TAC), concentration of pro-oxidants (TOS), lipid peroxidation (LPO) and protein carbonylation (PC)] in the yolk, liver and brain, and morphology. Yolk and liver antioxidant concentrations were positively correlated reciprocally and with embryo size, and positively predicted TAC but not oxidative status. TOS and LPO were positively correlated in the liver, while TAC and LPO were negatively correlated in the brain. Weak relationships existed between antioxidants and TOS, PC and LPO. The effects of antioxidants on oxidative status and morphology were non-synergistic. An experimental physiological increase in yolk vitamin E had very weak effects on the relationships between other antioxidants or oxidative status and vitamin E concentration, the concentration of other antioxidants or oxidative status; the covariation between other antioxidants and oxidative status, and relationships between morphology or oxidative status and other antioxidants, challenging the common wisdom of strong functional relationships among antioxidants, at least for embryos in the wild. © 2017. Published by The Company of Biologists Ltd.

  4. Satellite Tracking on the Flyways of Brown-Headed Gulls and Their Potential Role in the Spread of Highly Pathogenic Avian Influenza H5N1 Virus

    PubMed Central

    Ratanakorn, Parntep; Wiratsudakul, Anuwat; Wiriyarat, Witthawat; Eiamampai, Krairat; Farmer, Adrian H.; Webster, Robert G.; Chaichoune, Kridsada; Suwanpakdee, Sarin; Pothieng, Duangrat; Puthavathana, Pilaipan

    2012-01-01

    Brown-headed gulls (Larus brunnicephalus), winter visitors of Thailand, were tracked by satellite telemetry during 2008–2011 for investigating their roles in the highly pathogenic avian influenza (HPAI) H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam) affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1–2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak. PMID:23209623

  5. Thirty-seventh supplement to the American Ornithologists' Union checklist of North American birds

    USGS Publications Warehouse

    Monroe, Burt L.; Banks, Richard C.; Fitzpatrick, John W.; Howell, Thomas R.; Johnson, Ned K.; Ouellet, Henri; Remsen, J.V.; Storer, Robert W.

    1989-01-01

    This third supplement subsequent to the 6th edition (1983) of the A.O.U. "Check-list of North American Birds" consists of changes adopted by the Committee on Classification and Nomenclature as of 1 March 1989. The changes fall into nine categories: (1) six species are added to the main list (Pterodroma longirostris, Larus crassirostris, Streptopelia decaocto, Cocccyzus julieni, Chrysolampis mosquitus, Emberiza aureola) because of new distributional information; (2) five species (Ara cubensis, Chlorostilbon bracei, Empidonax occidentalis, Polioptila californica, Pipilo crissalis) are added to the main list because of the splitting of species already on the list; (3) one name (Anthus rubescens) is changed because of the splitting of a species from outside the Checklist area; (4) two names (Morus bassanus, Nyctanassa violacea) is removed from the main list to Appendix B because of re-evaluation of Northern Hemisphere records; (6) three species (Pterodrama rostrata, P. alba, P. solandri) are moved from Appendix A to Appendix B, and one (P. defilippiana) is added to Appendix B because of questionable sight records; (7)A.O.U. numbers are added to three species (Ciccaba virgata, Myiopagis viridicata, Molothrus bonariensis) on the basis on new distributional records or supporting data; (8) several corrections in spelling or citations are made; and (9) English names are changed for twelve species to accommodate worldwide usage of these names. No new distributional information is included except as indicated above (i.e. minor changes of distribution are not noted). These actions bring the number of species recognized as occurring in North America (main list) to 1,945.

  6. Evaluating cleansing effects on trace elements and stable isotope values in feathers of oiled birds.

    PubMed

    Valladares, Sonia; Moreno, Roćio; Jover, Lluis; Sanpera, Carola

    2010-01-01

    Feathers of seabirds are widely used as a nondestructive tissue for pollution monitoring of trace elements, as well as convenient samples for trophic ecology studies by means of stable isotope analysis (SIA). Nevertheless, feathers can be occasionally impregnated with oil from deliberate ship discharges and from massive oil spill accidents. The feather structure makes them effective traps for particles and are subject to external contamination. It is unknown to what extent the oil adhered to feathers can change trace element concentrations or stable isotope signatures. This study has two primary objectives: (1) to assess if there are differences between trace element concentrations and stable isotope signatures of oiled and clean feathers, and (2) to determine if the cleansing of oiled feathers using commonly applied techniques such as sodium hydroxide (NaOH) washes in combination with an organic solvent (hexane) is more effective than using NaOH alone. In order to do this, we analysed trace elements (Se, Hg, Pb, Cu and Zn) and stable isotopes (delta(13)C and delta(15)N) of individual feathers of yellow-legged gulls (Larus michahellis) which were affected by the 2002 Prestige oil spill in Galicia (NW Spain). Two sets of feathers were analysed, one group were oil-free (Control group) and the other had oil adhered to its surface (Oiled group). We expected to find differences between control and oiled feathers when cleaning exclusively with NaOH and no differences when using hexane. Our results did not show significant differences between Control and Oiled groups as a consequence of the cleansing method used. Unexpectedly, the additional cleansing with hexane resulted in decreasing selenium concentrations and increasing zinc and delta(15)N values in all groups of feathers.

  7. Using Seabird Habitat Modeling to Inform Marine Spatial Planning in Central California’s National Marine Sanctuaries

    PubMed Central

    McGowan, Jennifer; Hines, Ellen; Elliott, Meredith; Howar, Julie; Dransfield, Andrea; Nur, Nadav; Jahncke, Jaime

    2013-01-01

    Understanding seabird habitat preferences is critical to future wildlife conservation and threat mitigation in California. The objective of this study was to investigate drivers of seabird habitat selection within the Gulf of the Farallones and Cordell Bank National Marine Sanctuaries to identify areas for targeted conservation planning. We used seabird abundance data collected by the Applied California Current Ecosystem Studies Program (ACCESS) from 2004–2011. We used zero-inflated negative binomial regression to model species abundance and distribution as a function of near surface ocean water properties, distances to geographic features and oceanographic climate indices to identify patterns in foraging habitat selection. We evaluated seasonal, inter-annual and species-specific variability of at-sea distributions for the five most abundant seabirds nesting on the Farallon Islands: western gull (Larus occidentalis), common murre (Uria aalge), Cassin’s auklet (Ptychorampus aleuticus), rhinoceros auklet (Cerorhinca monocerata) and Brandt’s cormorant (Phalacrocorax penicillatus). The waters in the vicinity of Cordell Bank and the continental shelf east of the Farallon Islands emerged as persistent and highly selected foraging areas across all species. Further, we conducted a spatial prioritization exercise to optimize seabird conservation areas with and without considering impacts of current human activities. We explored three conservation scenarios where 10, 30 and 50 percent of highly selected, species-specific foraging areas would be conserved. We compared and contrasted results in relation to existing marine protected areas (MPAs) and the future alternative energy footprint identified by the California Ocean Uses Atlas. Our results show that the majority of highly selected seabird habitat lies outside of state MPAs where threats from shipping, oil spills, and offshore energy development remain. This analysis accentuates the need for innovative marine

  8. Reproductive success of the Black-crowned Night Heron at Alcatraz Island, San Francisco Bay, California, 1990-2002

    USGS Publications Warehouse

    Hothem, Roger L.; Hatch, Daphne

    2004-01-01

    Nesting chronology, habitat use, subcolony use, and hatchability were documented for the Black-crowned Night Heron (Nycticorax nycticorax) nesting at Alcatraz Island, San Francisco Bay, California during 1990-2002. Reproductive success was estimated using the Mayfield method and compared among years. Totals of monitored nests per year ranged from 68 in 2001 to 341 in 1996, with a trend of declining numbers since 1996. An increase in numbers of the Western Gull (Larus occidentalis), the Black-crowned Night Heron’s primary competitor, occurred during the same period. Overall reproductive success of the Black-crowned Night Heron at Alcatraz Island was below the 13-year average of 56.4% since 1996. During the study, the average number of chicks fledged per nest each year ranged from 0.46 to 1.27, which is less than the two chicks per nest suggested as a requirement for a sustained population. Embryos in five of 187 failed Black-crowned Night Heron eggs were deformed. In 1990 and 1991, eggs were analyzed for a wide range of contaminants, but none appeared to be sufficiently elevated to have caused the observed deformities. Based on these relatively low levels of contaminants, a high hatchability rate (94.5%), and relatively low levels of embryotoxicity, contaminants did not appear to significantly affect Black-crowned Night Heron reproduction at Alcatraz Island. However, predation by the Common Raven (Corvus corax) and Western Gull, interspecific competition with the Western Gull, habitat deterioration, and possible human disturbance are likely factors contributing to the decline in Black-crowned Night Heron reproductive success on Alcatraz Island in recent years.

  9. Effects of parental age and food availability on the reproductive success of Heermann's gulls in the Gulf of California.

    PubMed

    Vieyra, Leticia; Velarde, Enriqueta; Ezcurra, Exequiel

    2009-04-01

    Parental age, body condition, and food availability have been found to influence breeding parameters in seabirds, such as clutch size, number of chicks hatched and fledged, hatching, fledging, and reproductive success. In this paper we analyze the influence of parental age and body condition estimated by body mass, and food availability estimated from catch per unit effort (CPUE) statistics for Pacific sardine (Sardinops caeruleus) + northern anchovy (Engraulis mordax) by the local fishing fleet, on the breeding parameters of the Heermann's Gull (Larus heermanni; a vulnerable species according to Mexican federal law) nesting in Isla Rasa, Gulf of California, Mexico. Results are based on data from 1123 recaptures of known-age individuals, ranging from 4 to 13 years of age, during seven observation years between 1989 and 1997. Ages of mated male and female gulls were positively correlated. Breeding parameters showed their lowest values in 1992, an El Niño year in which the birds also showed significantly lower individual masses for both males and females, and in which the local CPUE of sardine + anchovies was lowest. All breeding parameters increased significantly with parental age and were highest at 10-12 years. No significant statistical interactions were found between food availability and parental age on the breeding parameters. Through a path analysis we found that there is a strong chained relationship between variables: food availability, which is strongly driven by oceanographic conditions, affects both the survival of eggs into hatchlings and the survival of hatchlings into fledglings. This external factor and parental age, a biological factor intrinsic to each nesting couple, explain 41% of the observed between-nest variation in fledgling success.

  10. Mathematical modeling of appendicular bone growth in glaucous-winged gulls.

    PubMed

    Hayward, James L; Henson, Shandelle M; Banks, John C; Lyn, Sheena L

    2009-01-01

    Development of locomotor activity is crucial in tetrapods. In birds, this development leads to different functions for hindlimbs and forelimbs. The emergence of walking and flying as very different complex behavior patterns only weeks after hatching provides an interesting case study in animal development. We measured the diaphyseal lengths and midshaft diameters of three wing bones (humerus, ulna, and carpometacarpus) and three leg bones (femur, tibiotarsus, and tarsometatarsus) of 79 juvenile (ages 0-42 days) and 13 adult glaucous-winged gulls (Larus glaucescens), a semiprecocial species. From a suite of nine alternative mathematical models, we used information-theoretic criteria to determine the best model(s) for length and diameter of each bone as a function of age; that is, we determined the model(s) that obtained the best tradeoff between the minimized sum of squared residuals and the number of parameters used to fit the model. The Janoschek and Holling III models best described bone growth, with at least one of these models yielding an R(2) > or = 0.94 for every dimension except tarsometatarsus diameter (R(2) = 0.87). We used the best growth models to construct accurate allometric comparisons of the bones. Early maximal absolute growth rates characterize the humerus, femur, and tarsometatarsus, bones that assume adult-type support functions relatively early during juvenile development. Leg bone lengths exhibit more rapid but less sustained relative growth than wing bone lengths. Wing bone diameters are initially smaller than leg bone diameters, although this relationship is reversed by fledging. Wing bones and the femur approach adult length by fledging but continue to increase in diameter past fledging; the tibiotarsus and tarsometatarsus approach both adult length and diameter by fledging. In short, the pattern of bone growth in this semiprecocial species reflects the changing behavioral needs of the developing organism.

  11. Evaluation of beach grooming techniques on Escherichia coli density in foreshore sand at North Beach, Racine, WI

    USGS Publications Warehouse

    Kinzelman, Julie L.; Whitman, Richard L.; Byappanahalli, Muruleedhara N.; Jackson, Emma; Bagley, Robert C.

    2003-01-01

    Elevated levels of Escherichia coli(E. coli) in bathing waters at North Beach, a popular recreational site in Racine, Wisconsin, have been a persistent problem often resulting in the issuance of poor water quality advisories. Moreover, waterfowl (mostly Larus delawarensis and L. argentatus) in nearshore and offshore areas are common and may serve as non-point sources for bacterial contamination of recreational waters. Current beach management practice involves daily mechanical grooming of the nearshore sand for aesthetics and removal of hazardous debris. However, this practice has not been evaluated in terms of its effects on E. coli loading to beach sand and potential introduction to contiguous swimming water. In this study, we tested E. coli responses to three treatments: mechanical groomer, daily and twice weekly hand raking, and a control (no raking/grooming). A randomized block design consisted of replicated treatments and one control (10 each), for a total of 40 blocks sampled daily for 10 days. Foreshore sand samples were collected by hand coring to an average depth of 10 cm. Median E. colirecovered were 73 (mechanically groomed), 27 (hand-raked daily), 32 (hand-raked twice weekly), and 22 (control) colony-forming units (CFU) per gram dry weight sand. E. colicounts in sand that was groomed were significantly higher than hand rakings and control (p <0.0001), and there was no significant difference between control and raking treatments (p<0.01). This study demonstrates the beach management implications related to grooming efficacy and the importance of understanding non-point sources of bacterial contamination.

  12. Forster's tern chick survival in response to a managed relocation of predatory California gulls

    USGS Publications Warehouse

    Ackerman, Joshua T.; Herzog, Mark P.; Hartman, C. Alex; Herring, Garth

    2014-01-01

    Gull populations can severely limit the productivity of waterbirds. Relocating gull colonies may reduce their effects on nearby breeding waterbirds, but there are few examples of this management strategy. We examined gull predation and survival of Forster's tern (Sterna forsteri) chicks before (2010) and after (2011) the managed relocation of the largest California gull (Larus californicus) colony (24,000 adults) in San Francisco Bay, California. Overall, survival of radio-marked Forster's tern chicks from hatching to fledging was 0.22 ± 0.03 (mean ± SE), and daily survival rates increased with age. Gulls were the predominant predator of tern chicks, potentially causing 54% of chick deaths. Prior to the gull colony relocation, 56% of radio-marked and 20% of banded tern chicks from the nearest tern colony were recovered dead in the gull colony, compared to only 15% of radio-marked and 4% of banded chicks recovered dead from all other tern colonies. The managed relocation of the gull colony substantially increased tern chick survival (by 900%) in the nearby (3.8 km) reference tern colony (0.29 ± 0.10 in 2010 and 0.25 ± 0.09 in 2011). Among 19 tern nesting islands, fledging success was higher when gull abundance was lower at nearby colonies and when gull colonies were farther from the tern colony. Our results indicate that the managed relocation of gull colonies away from preferred nesting areas of sensitive waterbirds can improve local reproductive success, but this conservation strategy may shift gull predation pressure to other areas or species.

  13. Toxoplasma gondii Infection in Seagull Chicks Is Related to the Consumption of Freshwater Food Resources.

    PubMed

    Cabezón, Oscar; Cerdà-Cuéllar, Marta; Morera, Virginia; García-Bocanegra, Ignacio; González-Solís, Jacob; Napp, Sebastian; Ribas, Maria P; Blanch-Lázaro, Berta; Fernández-Aguilar, Xavier; Antilles, Noelia; López-Soria, Sergio; Lorca-Oró, Cristina; Dubey, Jitender P; Almería, Sonia

    2016-01-01

    Understanding the spread of Toxoplasma gondii (T. gondii) in wild birds, particularly in those with opportunistic feeding behavior, is of interest for elucidating the epidemiological involvement of these birds in the maintenance and dissemination of the parasite. Overall, from 2009 to 2011, we collected sera from 525 seagull chicks (Yellow-legged gull (Larus michahellis) and Audouin's gull (L. audouinii)) from 6 breeding colonies in Spain and tested them using the modified agglutination test (MAT) for the presence of antibodies against T. gondii. Chick age was estimated from bill length. Main food source of seagull chicks was evaluated using stable isotope analyses from growing scapular feathers. Overall T. gondii seroprevalence was 21.0% (IC95% 17.5-24.4). A generalized linear mixed-effects model indicated that year (2009) and food source (freshwater) were risk factors associated to the individual risk of infection by T. gondii, while age (days) was close to significance. Freshwater food origin was related to the highest seroprevalence levels, followed by marine origin, supporting freshwater and sewages as important routes of dispersion of T. gondii. Year differences could indicate fluctuating rates of exposure of seagull chicks to T. gondii. Age ranged from 4 to 30 days and seropositivity tended to increase with age (P = 0.07), supporting that seropositivity is related to T. gondii infection rather than to maternal transfer of antibodies, which in gulls is known to sharply decrease with chick age. This study is the first to report T. gondii antibodies in Yellow-legged and Audouin's gulls, thereby extending the range of intermediate hosts for this parasite and underscoring the complexity of its epidemiology.

  14. Unintended consequences of management actions in salt pond restoration: cascading effects in trophic interactions.

    PubMed

    Takekawa, John Y; Ackerman, Joshua T; Brand, L Arriana; Graham, Tanya R; Eagles-Smith, Collin A; Herzog, Mark P; Topping, Brent R; Shellenbarger, Gregory G; Kuwabara, James S; Mruz, Eric; Piotter, Sara L; Athearn, Nicole D

    2015-01-01

    Salt evaporation ponds have played an important role as habitat for migratory waterbirds across the world, however, efforts to restore and manage these habitats to maximize their conservation value has proven to be challenging. For example, salinity reduction has been a goal for restoring and managing former salt evaporation ponds to support waterbirds in the South Bay Salt Pond Restoration Project in San Francisco Bay, California, USA. Here, we describe a case study of unexpected consequences of a low-dissolved oxygen (DO) event on trophic interactions in a salt pond system following management actions to reduce salinity concentrations. We document the ramifications of an anoxic event in water quality including salinity, DO, and temperature, and in the response of the biota including prey fish biomass, numerical response by California Gulls (Larus californicus), and chick survival of Forster's Tern (Sterna forsteri). Management actions intended to protect receiving waters resulted in decreased DO concentrations that collapsed to zero for ≥ 4 consecutive days, resulting in an extensive fish kill. DO depletion likely resulted from an algal bloom that arose following transition of the pond system from high to low salinity as respiration and decomposition outpaced photosynthetic production. We measured a ≥ 6-fold increase in biomass of fish dropped on the levee by foraging avian predators compared with weeks prior to and following the low-DO event. California Gulls rapidly responded to the availability of aerobically-stressed and vulnerable fish and increased in abundance by two orders of magnitude. Mark-recapture analysis of 254 Forster's Tern chicks indicated that their survival declined substantially following the increase in gull abundance. Thus, management actions to reduce salinity concentrations resulted in cascading effects in trophic interactions that serves as a cautionary tale illustrating the importance of understanding the interaction of water quality

  15. The translocation of white phosphorus from hen (Gallus domesticus) to egg

    SciTech Connect

    Nam, S.I.; MacMillan, D.L.; Roebuck, B.D.

    1996-09-01

    Thousands of waterfowl deaths occurring at Eagle River Flats (ERF), Anchorage, Alaska, have been attributed to the ingestion of white phosphorus (P{sub 4}) particles. White phosphorus has been found in the egg of one herring gull (Larus argentatus) and in the yolks of some shorebirds at ERF. The presence of P{sub 4} in eggs suggests potential toxic consequences for avian reproduction. This study was undertaken to determine the magnitude and potential importance of P{sub 4} translocation from the hen to the egg. Egg-laying hens (Gallus domesticus) were gavaged with a single dose of 1, 3, or 5 mg P{sub 4}/kg body weight or dosed with 1 mg P{sub 4}/kg body weight for 5 consecutive d. Eggs of dosed hens were collected daily. White phosphorus was extracted from the yolk and the white, individually, with isooctane and analyzed by gas chromatography. White phosphorus had no significant effect on chicken weight, egg weight, or shell thickness. However, laying frequency was significantly reduced (p < 0.05) in chickens receiving 1 mg P{sub 4}/kg body weight for 5 d. For all treatments, P{sub 4} was detected in the yolk and not in the white. It was first detected in the yolk approx. 1 to 2 d after P{sub 4} exposure and became nondetectable 6 to 10 d after P{sub 4} exposure. The total P{sub 4} recovered from eggs of chickens treated with P{sub 4} was less than 0.01% of the administered dose.

  16. Immune function and organochlorine pollutants in Arctic breeding glaucous gulls.

    PubMed

    Bustnes, J O; Hanssen, S A; Folstad, I; Erikstad, K E; Hasselquist, D; Skaare, J U

    2004-11-01

    Organochlorine contaminants (OCs) are known to affect the immune systems of wildlife, and in this study we assessed the relationship between blood concentration of different OCs and measurements relevant to immune status and function in arctic breeding glaucous gulls (Larus hyperboreus). In 1997 and 2001, we counted white blood cells (heterophils and lymphocytes) from blood smears, and in 2000 and 2001 we injected two novel nonpathogenic antigens (diphtheria and tetanus toxoids) into the pectoral muscle of gulls and measured the primary antibody responses. We then related these measurements to the blood concentrations of three pesticides (hexachlorobenzene [HCB], oxychlordane, and p,p'-dichlorodiphenyldichloroethylene) and seven different polychlorinated biphenyl congeners (PCB 101, 99, 118, 153, 138, 180, and 170). There were significant or near significant positive relationships (0.1 > p > 0.001) between most persistent OCs and the levels of heterophils in the blood for both sexes in 1997 and for male gulls in 2001. Similarly, levels of all persistent OCs and lymphocytes were positively related (0.1 > p > 0.001) in both sexes in 1997. This suggests that OCs are causing alterations to immune systems, which may decrease their efficiency and make the birds more susceptible to parasites and diseases. In female gulls, the antibody response to the diphtheria toxoid was significant and negative for HCB (p < 0.01) and weaker, but significant, for oxychlordane (p < 0.05), suggesting that OCs were causing an impairment of the humoral immunity. Various OCs have been linked to negative effects in our study population, including decreased survival and reproduction, and this study suggests that such compounds also affect immune status and function.

  17. In Vitro Metabolism of Photolytic Breakdown Products of Tetradecabromo-1,4-diphenoxybenzene Flame Retardant in Herring Gull and Rat Liver Microsomal Assays.

    PubMed

    Su, Guanyong; Greaves, Alana K; Teclechiel, Daniel; Letcher, Robert J

    2016-08-02

    Tetradecabromo-1,4-diphenoxybenzene (TeDB-DiPhOBz) is used as a flame retardant chemical and has been hypothesized to be the precursor of methoxylated polybrominated diphenoxybenzene (MeO-PB-DiPhOBz) contaminants reported in herring gulls from sites across the Laurentian Great Lakes. Here, by irradiating the parent TeDB-DiPhOBz (solution 1) with natural sunlight or UV, we prepared three solutions where solution 2 was dominated by the Br8-11-PB-DiPhOBzs, along with Br5-8-PB-DiPhOBzs (solution 3) and Br4-6-PB-DiPhOBzs (solution 4). The in vitro metabolism of TeDB-DiPhOBz and PB-DiPhOBzs was investigated using harvested wild herring gull (Larus argentatus) and adult male Wister-Han rat liver microsomal assays. After a 90 min incubation period of solution 1 in gull or rat microsomal assays, there was no significant (p > 0.05) depletion of TeDB-DiPhOBz. OH-PB-DiPhOBz metabolites were detectable after gull and rat microsomal assay incubation with solutions 3 or 4, and showed clear species-specific differences. Also detected were two polybrominated hydroxylated metabolites having polybenzofuran structures. Overall, this study suggested that TeDB-DiPhOBz is slowly metabolized in vitro, and also indicated that if wild herring gulls are exposed (e.g., via the diet) to photolytic products of TeDB-DiPhOBz, OH-PB-DiPhOBz and other metabolites could be formed. OH-PH-DiPhOBz are likely precursors to MeO-PB-DiPhOBz contaminants that we reported previously in eggs of wild Great Lakes herring gulls.

  18. A century of ecosystem change: human and seabird impacts on plant species extirpation and invasion on islands

    PubMed Central

    Bennett, Joseph R.; Blight, Louise K.; Giesen, Marissa; Janssen, Michael H.; Schaminée, Joop J.H.J.; Arcese, Peter

    2016-01-01

    We used 116 years of floral and faunal records from Mandarte Island, British Columbia, Canada, to estimate the indirect effects of humans on plant communities via their effects on the population size of a surface-nesting, colonial seabird, the Glaucous-winged gull (Larus glaucescens). Comparing current to historical records revealed 18 extirpations of native plant species (32% of species historically present), 31 exotic species introductions, and one case of exotic introduction followed by extirpation. Contemporary surveys indicated that native species cover declined dramatically from 1986 to 2006, coincident with the extirpation of ‘old-growth’ conifers. Because vegetation change co-occurred with an increasing gull population locally and regionally, we tested several predictions from the hypothesis that the presence and activities of seabirds help to explain those changes. Specifically, we predicted that on Mandarte and nearby islands with gull colonies, we should observe higher nutrient loading and exotic plant species richness and cover than on nearby islands without gull colonies, as a consequence of competitive dominance in species adapted to high soil nitrogen and trampling. As predicted, we found that native plant species cover and richness were lower, and exotic species cover and richness higher, on islands with versus without gull colonies. In addition, we found that soil carbon and nitrogen on islands with nesting gulls were positively related to soil depth and exotic species richness and cover across plots and islands. Our results support earlier suggestions that nesting seabirds can drive rapid change in insular plant communities by increasing nutrients and disturbing vegetation, and that human activities that affect seabird abundance may therefore indirectly affect plant community composition on islands with seabird colonies. PMID:27547531

  19. Thirty-seventh supplement to the American Ornithologists' Union Check-list of North American birds

    USGS Publications Warehouse

    Monroe, Burt L.; Banks, Richard C.; Fitzpatrick, John W.; Howell, Thomas R.; Johnson, Ned K.; Ouellet, Henri; Remsen, J.V.; Storer, Robert W.

    1989-01-01

    This third supplement subsequent to the 6th edition (1983) of the A.O.U. "Check-list of North American Birds" consists of changes adopted by the Committee on Classification and Nomenclature as of 1 March 1989. The changes fall into nine categories: (1) six species are added to the main list (Pterodroma longirostris, Larus crassirostris, Streptopelia decaocto, Cocccyzus julieni, Chrysolampis mosquitus, Emberiza aureola) because of new distributional information; (2) five species (Ara cubensis, Chlorostilbon bracei, Empidonax occidentalis, Polioptila californica, Pipilo crissalis) are added to the main list because of the splitting of species already on the list; (3) one name (Anthus rubescens) is changed because of the splitting of a species from outside the Checklist area; (4) two names (Morus bassanus, Nyctanassa violacea) is removed from the main list to Appendix B because of re-evaluation of Northern Hemisphere records; (6) three species (Pterodrama rostrata, P. alba, P. solandri) are moved from Appendix A to Appendix B, and one (P. defilippiana) is added to Appendix B because of questionable sight records; (7)A.O.U. numbers are added to three species (Ciccaba virgata, Myiopagis viridicata, Molothrus bonariensis) on the basis on new distributional records or supporting data; (8) several corrections in spelling or citations are made; and (9) English names are changed for twelve species to accommodate worldwide usage of these names. No new distributional information is included except as indicated above (i.e. minor changes of distribution are not noted). These actions bring the number of species recognized as occurring in North America (main list) to 1,945.

  20. [The mutation spectrum of the GJB2 gene in Belarussian patients with hearing loss. Results of pilot genetic screening of hearing impairment in newborns].

    PubMed

    Bliznets, E A; Marcul', D N; Khorov, O G; Markova, T G; Poliakov, A V

    2014-02-01

    A total of 111 unrelated probands and their 8 sibs from Grodno oblast (Belarus) with bilateral isolated sensorineural hearing impairment were studied for the presence of mutations in the connexin 26--GJB2gene. Mutations were detected in 51 probands (46% of the sample). A significantly higher frequency of the GJB2gene mutations was observed in familial cases of the disease with the autosomal recessive type of inheritance (in 78% of families). Detected peculiarities of the GJB2 gene mutation spectrum demonstrated that use of the algorithm, which was developed for Russian patients, is optimal for the molecular study of patients from Be- larus. In the sample of patients with hearing loss, the highest (among other similar samples studied in the world) allele frequency of c.313_326de114 mutation (7% out of all pathological GJB2 alleles) was registered; Polish origin of this deletion was suggested. It was demonstrated that detection of the GJB2 gene mutation on only one patient's chromosome is insufficient to confirm a molecular genetic diagnosis of hearing loss of the DFNB1 genetic type (autosomal recessive hearing loss caused by the GJB2 gene mutations). Pilot screening in the presence of GJB2 gene mutations in newborns from Grodno oblast was conducted. The material from 235 children was studied during the screening; nine heterozygous carriers of the mutation were found. The c.35delG mutation was detected in a homozygous state in a single newborn (hearing loss of moderate severity was subsequently audiologically confirmed in this child).

  1. Sex-specific foraging behavior in response to fishing activities in a threatened seabird.

    PubMed

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-06-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

  2. Varying foraging patterns in response to competition? A multicolony approach in a generalist seabird.

    PubMed

    Corman, Anna-Marie; Mendel, Bettina; Voigt, Christian C; Garthe, Stefan

    2016-02-01

    Reducing resource competition is a crucial requirement for colonial seabirds to ensure adequate self- and chick-provisioning during breeding season. Spatial segregation is a common avoidance strategy among and within species from neighboring breeding colonies. We determined whether the foraging behaviors of incubating lesser black-backed gulls (Larus fuscus) differed between six colonies varying in size and distance to mainland, and whether any differences could be related to the foraging habitats visited. Seventy-nine incubating individuals from six study colonies along the German North Sea coast were equipped with GPS data loggers in multiple years. Dietary information was gained by sampling food pellets, and blood samples were taken for stable isotope analyses. Foraging patterns clearly differed among and within colonies. Foraging range increased with increasing colony size and decreased with increasing colony distance from the mainland, although the latter might be due to the inclusion of the only offshore colony. Gulls from larger colonies with consequently greater density-dependent competition were more likely to forage at land instead of at sea. The diets of the gulls from the colonies furthest from each other differed, while the diets from the other colonies overlapped with each other. The spatial segregation and dietary similarities suggest that lesser black-backed gulls foraged at different sites and utilized two main habitat types, although these were similar across foraging areas for all colonies except the single offshore island. The avoidance of intraspecific competition results in colony-specific foraging patterns, potentially causing more intensive utilization of terrestrial foraging sites, which may offer more predictable and easily available foraging compared with the marine environment.

  3. Twenty years of temporal change in perfluoroalkyl sulfonate and carboxylate contaminants in herring gull eggs from the Laurentian Great Lakes.

    PubMed

    Gebbink, Wouter A; Letcher, Robert J; Hebert, Craig E; Chip Weseloh, D V

    2011-12-01

    In this study, temporal trends and patterns of major C(4) to C(15) chain length PFCAs and PFSAs and some sulfonamide, fluorotelomer acid and alcohol precursors were determined in herring gull (Larus argentatus) egg pools. Samples were analyzed from fifteen collection years including 1990 and all years from 1997 to 2010, and from seven colonies located throughout the Great Lakes, ranging from remote to highly urbanized areas. Other than at the Toronto Harbour colony, the slopes of ∑PFSA concentrations (C(6), C(8), and C(10)) versus time were negative indicating general declines between 1990 and 2010. PFOS was the dominant PFSA regardless of colony or year, ranging from 80 to 99% of ∑PFSA. For ∑PFCA (C(8)-C(15)), slopes of concentrations versus time were generally positive with 4 of 7 colonies showing statistically significant (p < 0.05) increases in levels through time. Individual PFCAs showed similar increasing trends except for PFOA. Regardless of colony, the PFCA pattern was dominated by the C(10) to C(13) PFCAs. Consistent with the PFOS declines, concentrations of the PFOS precursor, PFOSA, declined at most colonies between 1990 and 2006 and post-2006 concentrations were below detection limits. Declining concentrations of the C(8) PFCs, PFOS, PFOA and PFOSA, were consistent with the phase out in 2002 by the 3M Company in North America of all of C(8) PFC-related chemistry products. Increasing production volumes of fluorotelomer based compounds, and degradation of these compounds to PFCAs may explain increasing trends of PFCAs in gull eggs. Dietary changes as measured by carbon and nitrogen stable isotopes, showed minimal relationships to PFC levels in gull eggs, which indicates the complexity of aquatic and terrestrial food of gulls and sources of PFCs.

  4. Monitoring West Nile virus (WNV) infection in wild birds in Serbia during 2012: first isolation and characterisation of WNV strains from Serbia.

    PubMed

    Petrović, T; Blazquez, A B; Lupulović, D; Lazić, G; Escribano-Romero, E; Fabijan, D; Kapetanov, M; Lazić, S; Saiz, Jc

    2013-10-31

    West Nile virus (WNV), a neurovirulent mosquito-transmissible zoonotic virus, has caused recent outbreaks in Europe, including Serbia from August until October 2012. Although humans can be infected, birds are the main natural WNV reservoir. To assess WNV circulation in northern Serbia, 133 wild birds were investigated. These comprised resident and migratory birds, collected between January and September 2012 in the Vojvodina province. The birds belonged to 45 species within 27 families. Blood sera (n=92) and pooled tissues from respective birds (n=81) were tested by enzyme-linked immunosorbent assay (ELISA), plaque reduction neutralisation test (PRNT) and real-time reverse transcription-polymerase chain reaction (RT-qPCR). WNV antibodies were detected in seven (8%) sera: four from Mute Swans (Cygnus olor), two from White-tailed Eagles (Haliaeetus albicillas), and one from a Common Pheasant (Phasianus colchicus). Five sera neutralised WNV but not Usutu virus. For the first time in Serbia, WNV RNA was detected by RT-qPCR in pooled tissue samples of eight respective birds. WNV RNA was also derived from an additional bird, after a serum sample resulted infective in cell culture. The total nine WNV RNA positive birds included three Northern Goshawks (Accipiter gentilis), two White-tailed Eagles, one Legged Gull (Larus michahelis), one Hooded Crow (Corvus cornix), one Bearded Parrot-bill (Panarus biramicus), and one Common Pheasant. Phylogenetic analysis of partial E region sequences showed the presence of, at least, two lineage 2 Serbian clusters closely related to those responsible for recent human and animal outbreaks in Greece, Hungary and Italy. Full genomic sequence from a goshawk isolate corroborated this data. These results confirm WNV circulation in Serbia and highlight the risk of infection for humans and horses, pointing to the need for implementing WNV surveillance programmes.

  5. Satellite tracking on the flyways of brown-headed gulls and their potential role in the spread of highly pathogenic avian influenza H5N1 virus.

    PubMed

    Ratanakorn, Parntep; Wiratsudakul, Anuwat; Wiriyarat, Witthawat; Eiamampai, Krairat; Farmer, Adrian H; Webster, Robert G; Chaichoune, Kridsada; Suwanpakdee, Sarin; Pothieng, Duangrat; Puthavathana, Pilaipan

    2012-01-01

    Brown-headed gulls (Larus brunnicephalus), winter visitors of Thailand, were tracked by satellite telemetry during 2008-2011 for investigating their roles in the highly pathogenic avian influenza (HPAI) H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam) affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1-2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak.

  6. Organotins in marine mammals and seabirds from Norwegian territory.

    PubMed

    Berge, John Arthur; Brevik, Einar M; Bjørge, Arne; Følsvik, Norunn; Gabrielsen, Geir Wing; Wolkers, Hans

    2004-02-01

    An increasing number of studies indicate that marine mammals and some seabirds are exposed to organotins. However, results from northern and Arctic areas are few. Here results from analysis of tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT) and monophenyltin (MPhT) in harbour porpoise (Phocoena phocoena), common seal (Phoca vitulina), ringed seal (Phoca hispida) and glaucous gull (Larus hyperboreus) from Norwegian territory are presented. Relatively high concentrations of DBT, TBT and MBT were observed in muscle, kidney and liver from harbour porpoises caught in northern Norway in 1988, just before restrictions on the use of tributyltin (TBT)(mainly on small boats) were introduced in several European countries. The concentrations in harbour porpoise muscle tissue were reduced significantly 11 years later, possibly as a result of the introduced restrictions. Considerably lower concentrations of butyltins were observed in the seals compared to porpoises. The lowest levels of organotins were found in ringed seals from Spitsbergen, where only traces of dibutyltin (DBT) and monobutyltin (MBT) were observed. Traces of DBT and MBT were also found in some individual glaucous gulls from Bear Island. The sum of the degradation products MBT and DBT in liver samples from all analysed species were generally higher than TBT itself. Triphenyltin (TPhT) was observed in all porpoise samples and in livers of common seals. Also the sum of the degradation products MPhT and DPhT in liver samples from porpoise and common seals were higher than TPhT. No traces of phenyltins were found in ringed seals from Spitsbergen or in glaucous gulls from Bear Island. The limited data available indicate low to moderate exposure to organotins in northern areas (Spitsbergen and Bear Island). Marine mammals are however more exposed further south along the Norwegian Coast.

  7. Comparative reproductive biology of sympatric species: Nest and chick survival of American avocets and black-necked stilts

    USGS Publications Warehouse

    Ackerman, Joshua T.; Herzog, Mark P.; Takekawa, John Y.; Hartman, Christopher A.

    2014-01-01

    Identifying differences in reproductive success rates of closely related and sympatrically breeding species can be useful for understanding limitations to population growth. We simultaneously examined the reproductive ecology of American avocets Recurvirostra americana and black-necked stilts Himantopus mexicanus using 1274 monitored nests and 240 radio-marked chicks in San Francisco Bay, California. Although there were 1.8 times more avocet nests than stilt nests, stilts nonetheless fledged 3.3 times more chicks. Greater production by stilts than avocets was the result of greater chick survival from hatching to fledging (avocet: 6%; stilt: 40%), and not because of differences in clutch size (avocet: 3.84; stilt: 3.77), nest survival (avocet: 44%; stilt: 35%), or egg hatching success (avocet: 90%; stilt: 92%). We reviewed the literature and confirmed that nest survival and hatching success are generally similar when avocets and stilts breed sympatrically. In addition to species, chick survival was strongly influenced by age, site, and year. In particular, daily survival rates increased rapidly with chick age, with 70% of mortalities occurring ≤ 1 week after hatch. California gulls Larus californicus caused 55% of avocet, but only 15% of stilt, chick deaths. Differential use of micro-habitats likely reduced stilt chick’s vulnerability to gull predation, particularly during the first week after hatch, because stilts nested in vegetation 2.7 times more often than avocets and vegetation height was 65% taller at stilt nests compared with avocet nests. Our results demonstrate that two co-occurring and closely related species with similar life history strategies can differ markedly in reproductive success, and simultaneous studies of such species can identify differences that limit productivity.

  8. Regular habitat switch as an important feeding strategy of an opportunistic seabird species at the interface between land and sea

    NASA Astrophysics Data System (ADS)

    Schwemmer, Philipp; Garthe, Stefan

    2008-03-01

    During deteriorated prey availability, purely pelagic, specialised seabird species have to alter their feeding strategy by extending foraging radii and/or time spent at sea or reducing feeding intervals of chicks. In contrast, more generalised species such as the opportunistic black-headed gull ( Larus ridibundus) breeding at the German North Sea coast, can be assumed to react on prey shortages by switching foraging habitats. The coastal zone of the German North Sea provides a rich habitat mosaic consisting of the offshore zone, tidal flats and terrestrial habitats. Thus, we expected distinct temporal and spatial patterns of habitat switch in accordance with prey availability and environmental constraints. We carried out ship-based and aerial surveys as well as dietary analyses and observations on flight activity. We found a significant switch from terrestrial to marine feeding sites both on a daily basis (related to tidal cycle) and over the whole breeding season. Most likely, the latter switch is the result of lower prey availability in the terrestrial habitats and an increasing quality (in terms of prey abundance and energy intake) of the marine area. While there was only moderate variability in habitat use among different years, we revealed significant differences in the diet of birds from different colonies. The high dietary plasticity and flexible feeding strategy, switching between terrestrial and marine prey is certainly of major importance for the success of an opportunistic avian top predator in a complex coastal zone. It is suggested that - compared to situations elsewhere - the number of breeding pairs of black-headed gulls in the German North Sea coast are still stable due to the switch of foraging habitats performed by individuals in this region.

  9. Soils of the Galindez Island, Argentine archipelago, Western Antarctica

    NASA Astrophysics Data System (ADS)

    Abakumov, Evgeny; Parnikoza, Ivan

    2015-04-01

    Antarctic Peninsula is a part of Antarctica which is characterized by increased soil diversity, caused by specific of parent materials and diversity of non-vascular and vascular plants. Soils of Galindez Island have been investigated during the 18-th Ukranian Antarctic Expedition 2013/14. This Island situated in Argentine archipelago (coastal part of Antarctic Peninsula). Soils of Galindez Island presented by following types: Leptosols, Lithosols, Histic Lithosols and Leptosols and some Gleyic soils, located in lowlands and coastal parts. An average solum profile thickness is 3-19 cm which result from the small depth of debris's, underplayed by massive crystallic rocks. The permafrost layer is located within the massive rock, but not in coarse friable parent material. The soils with bird influence are widely spread both in coastal and central part of Island. In the coastal parts we can find typical Ornithosols in the penguin rockeries areas. The main aim of our investigation was characterization of soils formed under vegetation, exactly under Deschampsia antarctica Desv. localities. Argentine Islands is the central part of D. antarctica spreading area in region of Antarctic peninsula. Probably, these islands colonized by hairgrass mainly due to ornitogenic activity. So, coastal population appearance related with Larus dominicanus nest areas and feeding activity. Thus, we found typical post ornithogenic soils here. This kind of soils we also observed in population of hairgrass of Galindez mainland where it was connected with the other Antarctic bird - Catharacta maccormicki activity. Thus, the soil diversity and soil geochemistry of the Galindez Island are closely related to the activity of birds. The spatial pattern of soils, their chemistry and organic matter quality is discussed in relation with distribution of bird nesting and feeding activity.

  10. Wild Birds, Frequent Carriers of Extended-Spectrum β-Lactamase (ESBL) Producing Escherichia coli of CTX-M and SHV-12 Types.

    PubMed

    Alcalá, Leticia; Alonso, Carla Andrea; Simón, Carmen; González-Esteban, Chabier; Orós, Jesús; Rezusta, Antonio; Ortega, Carmelo; Torres, Carmen

    2016-11-01

    To get a better insight into the role of birds as reservoirs of extended-spectrum β-lactamase (ESBL) and plasmidic AmpC β-lactamase (pAmpC) Escherichia coli producers, 100 fecal samples belonging to 15 different wild avian species from Northern Spain were analyzed. Cefotaxime-resistant (CTX(R)) E. coli isolates were identified in 16 of the 100 tested birds, which corresponded to 9 animal species (Gyps fulvus-griffon vulture, Larus michahellis-yellow-legged gull, Milvus migrans-black kite, Milvus milvus-red kite, Ciconia ciconia-white stork, Sturnus unicolor-spotless starling, Aquila chrysaetos-golden eagle, Cuculus canorus-common cuckoo, Tyto alba-barn owl). Fifteen isolates harbored ESBL or pAmpC-encoding genes (number of isolates): bla SHV-12 (9), bla CTX-M-1 (3), bla CTX-M-14 (2), and bla CMY-2 (1). The last CTX(R) isolate presented a -42-point-mutation in the chromosomal ampC promoter. Eleven out of 15 ESBL/pAmpC E. coli isolates were multiresistant (most common resistance phenotype: β-lactams-quinolones-tetracycline-sulfamethoxazole/trimethoprim). A plasmid-mediated quinolone resistance determinant (qnrS1) was identified in one E. coli from a barn owl. High genetic diversity was observed among ESBL/pAmpC E. coli isolates, with 12 different sequence types (STs), including several strains of STs frequently detected among human clinical isolates (ST38/D, ST131/B2, ST155/B1, ST10/A). The ST131 isolate belonged to the emergent ciprofloxacin-resistant H30R subclone. This study reveals a high percentage of bird as carriers of ESBL/pAmpC E. coli isolates in Spain, highlighting the elevated rate among storks, kites, and vultures. Wild birds can contribute to the global spread of ESBL/pAmpC-producing E. coli in natural ecosystems.

  11. Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.

    USGS Publications Warehouse

    Anthony, R.G.; Estes, J.A.; Ricca, M.A.; Miles, A.K.; Forsman, E.D.

    2008-01-01

    Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993–1994 and 2000–2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993–1994 to 2000–2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex

  12. Influence of food availability on demography and local population dynamics in a long-lived seabird.

    PubMed Central

    Oro, Daniel; Cam, Emmanuelle; Pradel, Roger; Martínez-Abraín, Alejandro

    2004-01-01

    Few studies have addressed the effects of food availability as a proximate factor affecting local adult survival in long-lived organisms and their consequences at local population dynamics. We used capture-recapture analysis of resightings of 10 birth cohorts of ringed Audouin's gulls, Larus audouinii, to estimate adult survival and dispersal (both emigration and immigration). For the first time, permanent emigration (the transient effect in capture-recapture analysis) was modelled for the whole population and not only for the newly marked birds. Gulls exploit to a large extent fishes discarded from trawlers, and a trawling moratorium established since 1991 has decreased food supply for the colony. This was used as a natural experiment of food availability to assess its effects on adult survival and emigration. These and other demographic parameters were used in a projection modelling to assess the probabilities of extinction of the colony under two scenarios of lower and higher food availability. Food availability (together with the age of individuals) influenced emigration probabilities, but not adult survival, which was estimated at 0.91 (s.e. = 0.02). When food was in shorter supply during the chick-rearing period, emigration was very high (ca. 65%) for younger breeders, although this rate decreased sharply with age. Probabilities of extinction were very high when food availability was low, and when environmental stochasticity was introduced, and only stochastic immigration from the outside seemed to prevent extinction. The results highlight the importance of dispersal processes in the population dynamics of long-lived organisms. PMID:15101698

  13. Tracking the sources of polybrominated diphenyl ethers in birds: foraging in waste management facilities results in higher DecaBDE exposure in males.

    PubMed

    Gentes, Marie-Line; Mazerolle, Marc J; Giroux, Jean-François; Patenaude-Monette, Martin; Verreault, Jonathan

    2015-04-01

    Differences in feeding ecology are now recognized as major determinants of inter-individual variations in contaminant profiles of free-ranging animals, but exceedingly little attention has been devoted to the role of habitat use. Marked inter-individual variations and high levels of polybrominated diphenyl ethers (PBDEs) (e.g., DecaBDE) have previously been documented in ring-billed gulls (Larus delawarensis) breeding in a colony near Montreal (QC, Canada). However, the environmental sources of these compounds, and thus the reasons causing these large inter-individual variations remain unidentified. In the present study, we used GPS-based telemetry (±5 to 10m precision) to track ring-billed gulls from this colony to reconstruct their movements at the landscape level. We related habitat use of individual gulls (n=76) to plasma concentrations (ng/g ww) and relative contributions (percentages) to Σ38PBDEs of major congeners in the internationally restricted PentaBDE and current-use DecaBDE mixtures. Male gulls that visited waste management facilities (WMFs; i.e., landfills, wastewater treatment plants and related facilities; 25% of all GPS-tracked males) exhibited greater DecaBDE (concentrations and percentages) and lower PentaBDE (percentages) relative to those that did not. In contrast, no such relationships were found in females. Moreover, in males, DecaBDE (concentrations and percentages) increased with percentages of time spent in WMFs (i.e., ~5% of total foraging time), while PentaBDE (percentages) decreased. No relationships between percentages of time spent in other habitats (i.e., urban areas, agriculture fields, and St. Lawrence River) were found in either sex. These findings suggest that animals breeding in the vicinity of WMFs as well as mobile species that only use these sites for short stopovers to forage, could be at risk of enhanced DecaBDE exposure. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Variation in the Markers of Nutritional and Oxidative State in a Long-Lived Seabird: Associations with Age and Longevity.

    PubMed

    Urvik, Janek; Meitern, Richard; Rattiste, Kalev; Saks, Lauri; Hõrak, Peeter; Sepp, Tuul

    2016-01-01

    Age-related declines in life-history traits have been widely observed in free-living animals. Several theories link senescence to oxidative stress. The aim of this study was to measure several widely used markers of oxidative and nutritional state in a long-lived seabird, the common gull (Larus canus), in order to assess the suitability of these markers for describing deterioration in physiological condition associated with chronological age and survival. Associations with longevity and individual consistency of these parameters over the years (repeatability) were also assessed. Senescence in fitness parameters was observed during the study period: in females, laying date and clutch mass were related to bird age in a curvilinear manner, with middle-aged birds breeding earlier and laying heavier eggs. The only parameter associated with aging processes was glutathione concentration in erythrocytes, which was lower in female birds with longer life spans. Of indexes of nutritional state, plasma triglyceride concentration showed a between-individual increase with age, suggesting selective mortality of birds with low levels. Additionally, total plasma protein levels of individual males increased with age. The mostly negative results of this study hint that the commonly used parameters of physiological condition and oxidative state used in this study do not adequately reflect an individual's long-term health condition. Alternatively, it is possible that in common gulls, senescence occurs in reproductive mechanisms but not in mechanisms responsible for maintaining an organism's redox balance, consistent with the idea that different aspects of an organism's physiological condition age at different rates. Significant interannual repeatability was detected in three plasma constituents-carotenoids, uric acid, and total protein-all of which can possibly be linked to variation in dietary habits.

  15. Interactions of marine mammals and birds with offshore membrane enclosures for growing algae (OMEGA)

    PubMed Central

    2014-01-01

    Background OMEGA is an integrated aquatic system to produce biofuels, treat and recycle wastewater, capture CO2, and expand aquaculture production. This system includes floating photobioreactors (PBRs) that will cover hundreds of hectares in marine bays. To assess the interactions of marine mammals and birds with PBRs, 9 × 1.3 m flat panel and 9.5 × 0.2 m tubular PBRs were deployed in a harbor and monitored day and night from October 10, 2011 to Janurary 22, 2012 using infrared video. To observe interactions with pinnipeds, two trained sea lions (Zalophus californianus) and one trained harbor seal (Phoca vitulina richardii) were observed and directed to interact with PBRs in tanks. To determine the forces required to puncture PBR plastic and the effects of weathering, Instron measurements were made with a sea otter (Enhydra lutris) tooth and bird beaks. Results A total of 1,445 interactions of marine mammals and birds with PBRs were observed in the 2,424 hours of video recorded. The 95 marine mammal interactions, 94 by sea otters and one by a sea lion had average durations of three minutes (max 44 min) and represented about 1% of total recording time. The 1,350 bird interactions, primarily coots (Fulica americana) and gulls (Larus occidentalis and L. californicus) had average durations of six minutes (max. 170) and represented 5% of recording time. Interactive behaviors were characterized as passive (feeding, walking, resting, grooming, and social activity) or proactive (biting, pecking, investigating, and unspecified manipulating). Mammal interactions were predominantly proactive, whereas birds were passive. All interactions occurred primarily during the day. Ninety-six percent of otter interactions occurred in winter, whereas 73% of bird interactions in fall, correlating to their abundance in the harbor. Trained pinnipeds followed most commands to bite, drag, and haul-out onto PBRs, made no overt undirected interactions with the PBRs, but showed avoidance

  16. Ring distributions leading to species formation: a global topographic analysis of geographic barriers associated with ring species

    PubMed Central

    2012-01-01

    Background In the mid 20th century, Ernst Mayr and Theodosius Dobzhansky championed the significance of circular overlaps or ring species as the perfect demonstration of speciation, yet in the over 50 years since, only a handful of such taxa are known. We developed a topographic model to evaluate whether the geographic barriers that favor processes leading to ring species are common or rare, and to predict where other candidate ring barriers might be found. Results Of the 952,147 geographic barriers identified on the planet, only about 1% are topographically similar to barriers associated with known ring taxa, with most of the likely candidates occurring in under-studied parts of the world (for example, marine environments, tropical latitudes). Predicted barriers separate into two distinct categories: (i) single cohesive barriers (< 50,000 km2), associated with taxa that differentiate at smaller spatial scales (salamander: Ensatina eschscholtzii; tree: Acacia karroo); and (ii) composite barriers - formed by groups of barriers (each 184,000 to 1.7 million km2) in close geographic proximity (totaling 1.9 to 2.3 million km2) - associated with taxa that differentiate at larger spatial scales (birds: Phylloscopus trochiloides and Larus (sp. argentatus and fuscus)). When evaluated globally, we find a large number of cohesive barriers that are topographically similar to those associated with known ring taxa. Yet, compared to cohesive barriers, an order of magnitude fewer composite barriers are similar to those that favor ring divergence in species with higher dispersal. Conclusions While these findings confirm that the topographic conditions that favor evolutionary processes leading to ring speciation are, in fact, rare, they also suggest that many understudied natural systems could provide valuable demonstrations of continuous divergence towards the formation of new species. Distinct advantages of the model are that it (i) requires no a priori information on the relative

  17. Collision and displacement vulnerability among marine birds of the California Current System associated with offshore wind energy infrastructure

    USGS Publications Warehouse

    Adams, Josh; Kelsey, Emily C.; Felis, Jonathan J.; Pereksta, David M.

    2016-10-27

    With growing climate change concerns and energy constraints, there is an increasing need for renewable energy sources within the United States and globally. Looking forward, offshore wind-energy infrastructure (OWEI) has the potential to produce a significant proportion of the power needed to reach our Nation’s renewable energy goal. Offshore wind-energy sites can capitalize open areas within Federal waters that have persistent, high winds with large energy production potential. Although there are few locations in the California Current System (CCS) where it would be acceptable to build pile-mounted wind turbines in waters less than 50 m deep, the development of technology able to support deep-water OWEI (>200 m depth) could enable wind-energy production in the CCS. As with all human-use of the marine environment, understanding the potential impacts of wind-energy infrastructure on the marine ecosystem is an integral part of offshore wind-energy research and planning. Herein, we present a comprehensive database to quantify marine bird vulnerability to potential OWEI in the CCS (see https://doi.org/10.5066/F79C6VJ0). These data were used to quantify marine bird vulnerabilities at the population level. For 81 marine bird species present in the CCS, we created three vulnerability indices: Population Vulnerability, Collision Vulnerability, and Displacement Vulnerability. Population Vulnerability was used as a scaling factor to generate two comprehensive indicies: Population Collision Vulnerability (PCV) and Population Displacement Vulnerability (PDV). Within the CCS, pelicans, terns (Forster’s [Sterna forsteri], Caspian [Hydroprogne caspia], Elegant [Thalasseus elegans], and Least Tern [Sternula antillarum]), gulls (Western [Larus occidentalis] and Bonaparte’s Gull [Chroicocephalus philadelphia]), South Polar Skua (Stercorarius maccormicki), and Brandt’s Cormorant (Phalacrocorax penicillatus) had the greatest PCV scores. Brown Pelican (Pelicanus occidentalis

  18. Factors influencing nesting success of king eiders on northern Alaska's Coastal Plain

    USGS Publications Warehouse

    Bentzen, R.L.; Powell, A.N.; Suydam, R.S.

    2008-01-01

    King eider (Somateria spectabilis) populations have declined markedly in recent decades for unknown reasons. Nest survival is one component of recruitment, and a female's chance of reproductive success increases with her ability to choose an appropriate nesting strategy. We estimated variation in daily nest survival of king eiders at 2 sites, Teshekpuk and Kuparuk, Alaska, USA, 2002-2005. We evaluated both a priori and exploratory competing models of nest survival that considered importance of nest concealment, seclusion, and incubation constancy as strategies to avoid 2 primary egg predators, avian (Larus spp., Stercorarius spp., and Corvus corax) and fox (Alopex lagopus). We used generalized nonlinear techniques to examine factors affecting nest survival rates and information-theoretic approaches to select among competing models. Estimated nest survival, accounting for a nest visitation effect, varied considerably across sites and years (0.21-0.57); however, given our small sample size, much of this variation maybe attributable to sampling variation (??process = 0.007, 95% CI: 0.003-0.070). Nest survival was higher at Kuparuk than Teshekpuk in all years; however, due to the correlative nature of our data, we cannot determine the underlying causes with any certainty. We found mixed support for the concealed breeding strategy, females derived no benefit from nesting in areas with more willow (Salix spp.; measure of concealment) except that the observer effect diminished as willow cover increased. We suggest these patterns are due to conflicting predation pressures. Nest survival was not higher on islands (measure of seclusion) or with increased incubation constancy but was higher post-fox removal, indicating that predator control on breeding grounds could be a viable management option. Nest survival was negatively affected by our nest visitations, most likely by exposing the nest to avian scavengers. We recommend precautions be taken to limit the effects of nest

  19. 3,3',4,4'-Tetrachlorobiphenyl oxidation in fish, bird and reptile species: relationship to cytochrome P450 1A inactivation and reactive oxygen production.

    PubMed

    Schlezinger, J J; Keller, J; Verbrugge, L A; Stegeman, J J

    2000-03-01

    Previously we showed that the polychlorinated biphenyl 3,3',4,4'-tetrachlorobiphenyl (TCB) caused a release of reactive oxygen species (ROS) from cytochrome P450 1A (CYP1A) of the fish scup (Stenotomus chrysops), and from rat and human CYP1A1. This was linked to a TCB- and NADPH-dependent oxidative inactivation of the enzyme, which in scup and rat was inversely related to the rates of TCB oxidation. We examined the relationship between rates of TCB oxidation, CYP1A inactivation and ROS production in liver microsomes from additional vertebrate species, including skate (Raja erinacea), eel (Anguilla rostrata), killifish (Fundulus heteroclitus), winter flounder (Pleuronectes americanus), chicken (Gallus domesticus), cormorant (Phalacrocorax auritus), gull (Larus argentatus), and turtle (Chrysemys picta picta). TCB oxidation rates were induced in all fish and birds treated with aryl hydrocarbon receptor agonists. Induced rates of TCB oxidation were <1 pmol/min/mg microsomal protein in all fish, and 6-14 pmol/min/mg in the birds. In all species but one, TCB oxidation rates correlated positively with EROD rates, indicating likely involvement of CYP1A in TCB oxidation. Incubation of liver microsomes of most species with TCB+NADPH resulted in an immediate (TCB-dependent) inhibition of EROD, and a progressive loss of EROD capacity, indicating an oxidative inactivation of CYP1A like that in scup. NADPH stimulated production of ROS (H(2)O(2) and/or O(2)(-*)) by liver microsomes, slightly in some species (eel) and greatly in others (chicken, turtle). Among the birds and the fish, NADPH-stimulated ROS production correlated positively with EROD activity. TCB caused a significant stimulation of ROS production by liver microsomes of flounder, killifish, cormorant and gull, as well as scup. The stimulation of CYP1A inactivation and ROS generation indicates an uncoupling of CYP1A by TCB in many species, and when compared between species, the rates of CYP1A inactivation correlated

  20. Interactions of marine mammals and birds with offshore membrane enclosures for growing algae (OMEGA).

    PubMed

    Hughes, Stephanie N; Tozzi, Sasha; Harris, Linden; Harmsen, Shawn; Young, Colleen; Rask, Jon; Toy-Choutka, Sharon; Clark, Kit; Cruickshank, Marilyn; Fennie, Hamilton; Kuo, Julie; Trent, Jonathan D

    2014-01-01

    OMEGA is an integrated aquatic system to produce biofuels, treat and recycle wastewater, capture CO2, and expand aquaculture production. This system includes floating photobioreactors (PBRs) that will cover hundreds of hectares in marine bays. To assess the interactions of marine mammals and birds with PBRs, 9 × 1.3 m flat panel and 9.5 × 0.2 m tubular PBRs were deployed in a harbor and monitored day and night from October 10, 2011 to Janurary 22, 2012 using infrared video. To observe interactions with pinnipeds, two trained sea lions (Zalophus californianus) and one trained harbor seal (Phoca vitulina richardii) were observed and directed to interact with PBRs in tanks. To determine the forces required to puncture PBR plastic and the effects of weathering, Instron measurements were made with a sea otter (Enhydra lutris) tooth and bird beaks. A total of 1,445 interactions of marine mammals and birds with PBRs were observed in the 2,424 hours of video recorded. The 95 marine mammal interactions, 94 by sea otters and one by a sea lion had average durations of three minutes (max 44 min) and represented about 1% of total recording time. The 1,350 bird interactions, primarily coots (Fulica americana) and gulls (Larus occidentalis and L. californicus) had average durations of six minutes (max. 170) and represented 5% of recording time. Interactive behaviors were characterized as passive (feeding, walking, resting, grooming, and social activity) or proactive (biting, pecking, investigating, and unspecified manipulating). Mammal interactions were predominantly proactive, whereas birds were passive. All interactions occurred primarily during the day. Ninety-six percent of otter interactions occurred in winter, whereas 73% of bird interactions in fall, correlating to their abundance in the harbor. Trained pinnipeds followed most commands to bite, drag, and haul-out onto PBRs, made no overt undirected interactions with the PBRs, but showed avoidance behavior to PBR

  1. Fishing gear-related injury in California marine wildlife.

    PubMed

    Dau, Brynie Kaplan; Gilardi, Kirsten V K; Gulland, Frances M; Higgins, Ali; Holcomb, Jay B; Leger, Judy St; Ziccardi, Michael H

    2009-04-01

    We reviewed medical records from select wildlife rehabilitation facilities in California to determine the prevalence of injury in California Brown Pelicans (Pelecanus occidentalis), gulls (Larus spp.), and pinniped species (Zalophus californianus, Mirounga angustirostris, and Phoca vitulina) due to fishing gear entanglement and ingestion from 2001 to 2006. Of 9,668 Brown Pelican, gull, and pinniped cases described during the 6-yr study period (2001-06), 1,090 (11.3%) were fishing gear-related. Pelican injuries caused by fishing gear were most common in the Monterey Bay region, where 59.6% of the pelicans rescued in this area and admitted to a rehabilitation center were injured by fishing gear over the 6-yr period. The highest prevalence of fishing gear-related injury in gulls was documented in the Los Angeles/Orange County region (16.1%), whereas the highest prevalences in pinnipeds were seen in the San Diego region (3.7%). Despite these higher prevalences of gull and pinniped fishing gear-related injuries in these specific regions, there was no statistical significance in these trends. Juvenile gulls and pinnipeds were more commonly injured by fishing gear than adults (gulls: P = 0.03, odds ratio = 1.29; pinnipeds: P = 0.01, odds ratio = 2.07). Male pinnipeds were twice as likely to be injured by fishing gear as females (P < 0.01, odds ratio = 2.19). The proportion of fishing gear-related injury cases that were successfully rehabilitated and released (percentage of cases successfully rehabilitated to the point of release out of the total number of fishing gear-related injury cases) was high in all three species groups (pelicans: 63%; gulls: 54%; pinnipeds: 70%). Fishing gear-related injuries in Brown Pelicans and gulls were highest in the fall, but there was only a significant difference between seasons for fishing gear-related injuries in pelicans. Fishing gear-related injuries in pinnipeds most commonly occurred in summer; however, a statistical difference was

  2. Seabird population trends along the west coast of North America: causes and the extent of regional concordance

    USGS Publications Warehouse

    Ainley, D.G.; Sydeman, W.J.; Hatch, Shyla A.; Wilson, U.W.

    1994-01-01

    We compared trends in breeding population size among cormorants, gulls, alcids, and others, among the Farallon Islands, and sites in northern California and Washington, Gulf of Alaska, and Bering Sea, but in most cases only during the last two decades. For a given species, trends were usually concordant within the same oceanographic domain, except for Rhinoceros Auklet, which increased across all domains in its northeastern Pacific range. Overall, humans and their domestic animals have had severe negative impacts to individual islands, but recent restoration efforts have had spectacular results. On the other hand, the California Current and the eastern Bering Sea now seem unable to support historic populations of natural, top-trophic predators. The major factor responsible appears to be overfishing by humans of important seabird prey, especially, in a period when climate has been unstable. Notable trends indicating these general patterns were as follows: 1) The Ashy Storm-Petrel on the Farallon Islands, where 80% of this species breeds, may have decreased in response to the increase of gulls in the storm-petrel breeding habitat. 2) Brandt's and Pelagic cormorants in the central California Current declined radically owing to El Nino and antropogenic factors in the early 1980s, and have since failed to recover, contrary to trends in the 1970s; farther north, populations fluctuated slightly but at low levels during this period. 3) Large Larus gulls have increased. 4) Common Murres in the central and northern portions of the California Current exhibited a marked decline during the early 1980s and have since failed to recover. 5) Most Common Murre populations in the Gulf of Alaska appear to be stable; whereas those in the eastern Bering Sea are decreasing. 6) Rhinoceros Auklet has increased throughout its range and has (re-)colonized new sites in the southern portion of it. 7) Tufted Puffin has ceased recovery in the California Current, but in Alaska it has continued to

  3. Managing birds and controlling aircraft in the Kennedy Airport-Jamaica Bay Wildlife Refuge complex: the need for hard data and soft opinions

    USGS Publications Warehouse

    Brown, K.M.; Erwin, R.M.; Richmond, M.E.; Buckley, P.A.; Tanacredi, J.T.; Avrin, D.

    2001-01-01

    During the 1980s, the exponential growth of laughing gull (Larus atrfcilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes, at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%) of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 + 6 aircraft/yr, N = 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over 50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined from 6.9 + 2.9 (1983-1990) to 2.8 + 1.3 (1991-1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled (6.4 + 2.6, 1983-1990; 14.9 + 5.1, 1991-1998). We found no evidence to indicate that on-colony management would yield a reduction of bird strikes at Kennedy Airport. Dietary and mark-recapture studies suggest that 60%-90% of the laughing gulls collected on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the capability of the bird control unit to eliminate

  4. Quantifying avian predation on fish populations: integrating predator-specific deposition probabilities in tag-recovery studies

    USGS Publications Warehouse

    Hostetter, Nathan J.; Evans, Allen F.; Cramer, Bradley M.; Collis, Ken; Lyons, Donald E.; Roby, Daniel D.

    2015-01-01

    Accurate assessment of specific mortality factors is vital to prioritize recovery actions for threatened and endangered species. For decades, tag recovery methods have been used to estimate fish mortality due to avian predation. Predation probabilities derived from fish tag recoveries on piscivorous waterbird colonies typically reflect minimum estimates of predation due to an unknown and unaccounted-for fraction of tags that are consumed but not deposited on-colony (i.e., deposition probability). We applied an integrated tag recovery modeling approach in a Bayesian context to estimate predation probabilities that accounted for predator-specific tag detection and deposition probabilities in a multiple-predator system. Studies of PIT tag deposition were conducted across three bird species nesting at seven different colonies in the Columbia River basin, USA. Tag deposition probabilities differed significantly among predator species (Caspian ternsHydroprogne caspia: deposition probability = 0.71, 95% credible interval [CRI] = 0.51–0.89; double-crested cormorants Phalacrocorax auritus: 0.51, 95% CRI = 0.34–0.70; California gulls Larus californicus: 0.15, 95% CRI = 0.11–0.21) but showed little variation across trials within a species or across years. Data from a 6-year study (2008–2013) of PIT-tagged juvenile Snake River steelhead Oncorhynchus mykiss (listed as threatened under the Endangered Species Act) indicated that colony-specific predation probabilities ranged from less than 0.01 to 0.17 and varied by predator species, colony location, and year. Integrating the predator-specific deposition probabilities increased the predation probabilities by a factor of approximately 1.4 for Caspian terns, 2.0 for double-crested cormorants, and 6.7 for California gulls compared with traditional minimum predation rate methods, which do not account for deposition probabilities. Results supported previous findings on the high predation impacts from strictly piscivorous

  5. Residues and trends of organochlorine pesticide and polychlorinated biphenyls in birds from Texas, 1965-88

    USGS Publications Warehouse

    Mora, Miguel A.

    1995-01-01

    Concentrations of DDE (a metabolite of DDT) in birds decreased during recent years in most areas of the continental United States. Organochlorine pesticides were widely used in agriculture in Texas from the early 1950s to the 1970s. I used previously published data to determine whether concentrations of DDE and polychlorinated biphenyls (PCBs) in birds from Texas have followed a decreasing trend similar to that in birds from other areas in the United States. A total of 2,669 bird samples was collected between 1965 and 1988 from diverse locations in Texas and was analyzed for organochlorines and other environmental contaminants. The brown pelican (Pelecanus occidentalis), peregrine falcon (Falco peregrinus), laughing gull (Larus atricilla), black skimmer (Rynchops niger), and European starling (Sturnus vulgaris) were the most frequently studied species. DDE and PCBs were the most commonly detected organochlorines in bird tissues. Mean DDE concentrations ranged from 0.4 to 61.00 parts per million (ppm) wet weight (ww) and PCBs from 0.02 to 32.00 ppm ww. Concentrations of DDE in eggs and carcasses of black skimmers decreased significantly during 1970-84 and dropped from approximately 10 to nearly 3 ppm ww. PCBs decreased from approximately 7 ppm ww to 1 ppm ww in eggs and carcasses. DDE concentrations in eggs of brown pelicans varied from more than 3 ppm ww in 1970 to approximately 1 ppm ww in 1983; and PCB concentrations diminished from about 10 to 1 ppm ww. Decreasing trends in concentrations of DDE and PBCs were observed in most species, although in some cases, the estimated trends were not significantly different from zero. Concentrations of DDE in birds from the Texas coast decreased from more than 6.0 ppm in 1978 to below 0.5 ppm in 1985. The decreasing ratios in selected species varied from approximately 2.0 to 12.0 (DDE) and from 4.5 to 9.0 (PCBs). The results indicate that in general from 1965 to 1988, DDE and PCBs declined in birds from Texas.

  6. Biomagnification factors (fish to Osprey eggs from Willamette River, Oregon, U.S.A.) for PCDDs, PCDFs, PCBs and OC pesticides.

    PubMed

    Henny, Charles J; Kaiser, James L; Grove, Robert A; Bentley, V Raymond; Elliott, John E

    2003-06-01

    Osprey were compared to BMFs for the resident Herring Gull (Larus argentatus), and differences are discussed. We believe a BMF approach provides some basic understanding of relationships between contaminant burdens in prey species of fish-eating birds and contaminants incorporated into their eggs, and may prove useful in understanding sources of contaminants in migratory species although additional studies are needed.

  7. Biomagnification factors (fish to osprey eggs from Willamette River, Oregon, U.S.A.) for PCDDS, PCDFS, PCBS, and OC pesticides

    USGS Publications Warehouse

    Henny, Charles J.; Kaiser, James L.; Grove, Robert A.; Bentley, V.R.; Elliot, J.E.

    2003-01-01

    HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.

  8. Terrestrial and Marine Foraging Strategies of an Opportunistic Seabird Species Breeding in the Wadden Sea

    PubMed Central

    Schwemmer, Philipp; Paiva, Vitor H.; Corman, Anna-Marie; Fock, Heino O.; Voigt, Christian C.; Adler, Sven

    2016-01-01

    Lesser black-backed gulls Larus fuscus are considered to be mainly pelagic. We assessed the importance of different landscape elements (open sea, tidal flats and inland) by comparing marine and terrestrial foraging behaviours in lesser black-backed gulls breeding along the coast of the southern North Sea. We attached GPS data loggers to eight incubating birds and collected information on diet and habitat use. The loggers recorded data for 10–19 days to allow flight-path reconstruction. Lesser black-backed gulls foraged in both offshore and inland areas, but rarely on tidal flats. Targets and directions were similar among all eight individuals. Foraging trips (n = 108) lasted 0.5–26.4 h (mean 8.7 h), and ranges varied from 3.0–79.9 km (mean 30.9 km). The total distance travelled per foraging trip ranged from 7.5–333.6 km (mean 97.9 km). Trips out to sea were significantly more variable in all parameters than inland trips. Presence in inland areas was closely associated with daylight, whereas trips to sea occurred at day and night, but mostly at night. The most common items in pellets were grass (48%), insects (38%), fish (28%), litter (26%) and earthworms (20%). There was a significant relationship between the carbon and nitrogen isotope signals in blood and the proportional time each individual spent foraging at sea/land. On land, gulls preferentially foraged on bare ground, with significantly higher use of potato fields and significantly less use of grassland. The flight patterns of lesser black-backed gulls at sea overlapped with fishing-vessel distribution, including small beam trawlers fishing for shrimps in coastal waters close to the colony and large beam-trawlers fishing for flatfish at greater distances. Our data show that individuals made intensive use of the anthropogenic landscape and seascape, indicating that lesser black-backed gulls are not a predominantly marine species during the incubation period. PMID:27525661

  9. Changing landscapes and the cosmopolitism of the eastern Colorado avifauna

    USGS Publications Warehouse

    Knopf, Fritz L.

    1986-01-01

    The avifauna of continental North America has changed dramatically since colonial times. Excessive hunting contributed, at least in part, to the extinction of birds such as the great auk (Pinguinus impennis) and passenger pigeon (Ectopistes migratorius), while more recently organochlorine insecticide residues have resulted in drastic reductions in numbers of brown pelicans (Pelecanus occidentalis) (Anderson et al. 1975) and other species. Generally, however, vertebrate populations change in direct response to changes in their habitats. For example, herring gulls (Larus argentatus) have increased in numners (Kadlec and Drury 1968) with urbanization of the New England coastline, in the same locations formerly occupied by the extinct heath hen (Tympanuchus cupido cupido). Also, passerine birds of forest interiors have declined in numbers with fragmentation of the eastern deciduous forest into small stands; this fragmentation has led to increases in numbers of edge species (Robbins 1979, Ambuel and Temple 1983). Even subtle community shifts can introduce new competitive processes that can augment population changes among species (Brittingham and Temple 1983). Such studies of broad-scale changes in vegetative communities and their influence on native wildlife species have fostered the recent topical emphasis on "conservation biology" (Soule and Wilcox 1980, Soule 1985) and "landscape ecology" (Burgess and Sharpe 1981, Harris 1984:25-43). As changes in landscapes are causing subtle (but potentially dramatic) changes in the distribution of native species, conservation biologists are finding that mere presence-absence data on populations, or even accurate information on reproductive success, is inadequate to evaluate management activities or environmental perturbations. The principles of "conservation genetics" are attracting interest in the management of natural preserves especially (Schonewald-Cox et al. 1983). Changing patterns in landscape complexion or genetic makeup

  10. Use of Wetland Habitats by Selected Nongame Water Birds in Maine

    USGS Publications Warehouse

    Gibbs, J.P.; Longcore, J.R.; McAuley, D.G.; Ringelman, J.K.

    1991-01-01

    We examined the use of 87 palustrine and lacustrine wetlands by nongame water birds in central and eastern Maine using 3,527 h of observation (1,501 visits) made during April-August, 1977-85. Wetlands used by 15 species of water birds were distinguished from those not used, according to 20 habitat features. The species were the common loon (Gavia immer) , pied-billed grebe (Podilymbus podiceps), double-crested cormorant (Phalacrocorax auritus), American bittern (Botaurus lentiginosus), great blue heron (Ardea herodias), green-backed heron (Butorides striatus), osprey (Pandion haliaetus), bald eagle (Haliaeetus leucocephalus), northern harrier (Circus cyaneus), Virgima rail (Rallus limicola), sora (Porzana carolina), spotted sandpiper (Actitis macularia), common snipe (Gallinago gallinago), herring gull (Larus argentatus), and belted kingfisher (Ceryle alcyon). Predictive models of habitat use were developed for each species. Water birds were classified by similarity of habitats used, and species use was contrasted by wetland type. Smaller, isolated wetlands were used by fewer (P 66%) or open (<33%) wetlands. Low pH typified wetlands used by large-bodied piscivores (common loon, cormorant, osprey). Other water birds were associated with more densely vegetated, chemically buffered wetlands. Habitat features associated with wetland use by each waterbird species are reported, as are numerical responses of waterbird populations to wetland features and estimates of annual variation in habitat occupancy. Lacustrine wetlands supported a distinct, low diversity community of water birds, including most fish-eating species. Waterbird diversity at forested palustrine wetlands was intermediate between lacustrine communities and more species-rich assemblages at palustrine emergent and scrub-shrub wetlands. Regional variation in wetland characteristics and water bird use was associated with surficial geology, soils, and management practices. Management for nongame water birds in

  11. Linear and branched perfluorooctane sulfonate isomer patterns in herring gull eggs from colonial sites across the Laurentian Great Lakes.

    PubMed

    Gebbink, Wouter A; Letcher, Robert J

    2010-05-15

    Linear and branched (six mono(trifluoromethyl) and four di(trifluoromethyl)) isomers of the bioaccumulative contaminant perfluorooctane sulfonate (PFOS) were analyzed for and the spatial patterns examined in individual herring gull (Larus argentatus) eggs (n = 13 per site) collected (in 2007) from 15 colonies across the Laurentian Great Lakes of North America. Linear PFOS (n-perfluoro-1-octanesulfonate (L-PFOS)) consistently dominated the isomer pattern in all eggs, comprising between 95.0% and 98.3% of the summation sigmaPFOS concentration. L-PFOS was highly enriched in the gull eggs as the summation sigmabranched-PFOS to L-PFOS isomer concentration ratios were very constant (overall average 0.038 +/- 0.001) and much lower compared to technical PFOS (range 0.27-0.54). The highest proportions of L-PFOS were generally observed in the eggs from the lower lakes (Erie and Ontario) colonies. All six mono(trifluoromethyl) branched isomers, or perfluoro-n-methyl-heptanesulfonates where n describes the carbon of the hydrocarbon chain were there is trifluoromethyl substitution relative to the sulfonate terminal group, were detected in the eggs from all the colonies. For example, P1MHpS is perfluoro-1-methyl-heptanesulfonate. Comparable to technical PFOS (T-PFOS), the percentage of the mono(trifluoromethyl) isomer to summation sigmaPFOS concentration decreased as the branch substitution was located closer to the sulfonate group, that is, P6MHpS (0%-2.5%), P5MHpS (0.43%-1.18%), P4MHpS (0.25%-0.69%), and P3MHpS (0.32%-0.74%). Although at even lower fractional composition than the mono(trifluoromethyl) isomers, of the di(trifluoromethyl) isomers, detected in >60% of the individual eggs per site was P35DMHxS and P45DMHxS for Toronto Harbour (Lake Ontario), P35DMHxS for Chantry (Lake Huron) and Fighting Island (Detroit River), and P45DMHxS for Gull Island (Lake Michigan). Relative to T-PFOS, and independent of colonial location, the high and consistent enrichment of L-PFOS in

  12. Tracking the sources of polybrominated diphenyl ethers in birds: Foraging in waste management facilities results in higher DecaBDE exposure in males

    SciTech Connect

    Gentes, Marie-Line; Mazerolle, Marc J.; Giroux, Jean-François; Patenaude-Monette, Martin; and others

    2015-04-15

    Differences in feeding ecology are now recognized as major determinants of inter-individual variations in contaminant profiles of free-ranging animals, but exceedingly little attention has been devoted to the role of habitat use. Marked inter-individual variations and high levels of polybrominated diphenyl ethers (PBDEs) (e.g., DecaBDE) have previously been documented in ring-billed gulls (Larus delawarensis) breeding in a colony near Montreal (QC, Canada). However, the environmental sources of these compounds, and thus the reasons causing these large inter-individual variations remain unidentified. In the present study, we used GPS-based telemetry (±5 to 10 m precision) to track ring-billed gulls from this colony to reconstruct their movements at the landscape level. We related habitat use of individual gulls (n=76) to plasma concentrations (ng/g ww) and relative contributions (percentages) to Σ{sub 38}PBDEs of major congeners in the internationally restricted PentaBDE and current-use DecaBDE mixtures. Male gulls that visited waste management facilities (WMFs; i.e., landfills, wastewater treatment plants and related facilities; 25% of all GPS-tracked males) exhibited greater DecaBDE (concentrations and percentages) and lower PentaBDE (percentages) relative to those that did not. In contrast, no such relationships were found in females. Moreover, in males, DecaBDE (concentrations and percentages) increased with percentages of time spent in WMFs (i.e., ~5% of total foraging time), while PentaBDE (percentages) decreased. No relationships between percentages of time spent in other habitats (i.e., urban areas, agriculture fields, and St. Lawrence River) were found in either sex. These findings suggest that animals breeding in the vicinity of WMFs as well as mobile species that only use these sites for short stopovers to forage, could be at risk of enhanced DecaBDE exposure. - Highlights: • The study was conducted on breeding gulls with high levels of flame

  13. Molecular and epidemiological characterization of avian influenza viruses from gulls and dabbling ducks in Norway

    PubMed Central

    2013-01-01

    Background Wild aquatic birds constitute the natural reservoir for avian influenza viruses (AIVs). Separate Eurasian and American AIV gene pools exist. Here, the prevalence and diversity of AIVs in gulls and dabbling ducks in Norway were described. The influence of host species and temporal changes on AIV prevalence was examined. Five AIVs from Norway, including three from common gull (Larus canus), were analyzed along with 10 available AIV genomes from gulls in Eurasia to search for evidence of intracontinental and intercontinental reassortment of gene segments encoding the internal viral proteins. Methods Swabs collected from 2417 dabbling ducks and gulls in the south-west of Norway during five ordinary hunting seasons (August-December) in the period 2005–2010 were analyzed for presence of AIV. Multivariate linear regression was used to identify associations between AIV prevalence, host species and sampling time. Five AIVs from mallard (Anas platyrhynchos) (H3N8, H9N2) and common gull (H6N8, H13N2, H16N3) were full-length characterized and phylogenetically analyzed together with GenBank reference sequences. Results Low pathogenic AIVs were detected in 15.5% (CI: 14.1–17.0) of the samples. The overall AIV prevalence was lower in December compared to that found in August to November (p = 0.003). AIV was detected in 18.7% (CI: 16.8–20.6) of the dabbling ducks. A high AIV prevalence of 7.8% (CI; 5.9–10.0) was found in gulls. A similar temporal pattern in AIV prevalence was found in both bird groups. Thirteen hemagglutinin and eight neuraminidase subtypes were detected. No evidence of intercontinental reassortment was found. Eurasian avian (non H13 and H16) PB2 or PA genes were identified in five reference Eurasian gull (H13 and H16) AIV genomes from GenBank. The NA gene from the Norwegian H13N2 gull isolate was of Eurasian avian origin. Conclusions The similar temporal pattern in AIV prevalence found in dabbling ducks and gulls, the relatively high virus

  14. Molecular and epidemiological characterization of avian influenza viruses from gulls and dabbling ducks in Norway.

    PubMed

    Tønnessen, Ragnhild; Kristoffersen, Anja B; Jonassen, Christine M; Hjortaas, Monika J; Hansen, Elisabeth F; Rimstad, Espen; Hauge, Anna G

    2013-04-10

    Wild aquatic birds constitute the natural reservoir for avian influenza viruses (AIVs). Separate Eurasian and American AIV gene pools exist. Here, the prevalence and diversity of AIVs in gulls and dabbling ducks in Norway were described. The influence of host species and temporal changes on AIV prevalence was examined. Five AIVs from Norway, including three from common gull (Larus canus), were analyzed along with 10 available AIV genomes from gulls in Eurasia to search for evidence of intracontinental and intercontinental reassortment of gene segments encoding the internal viral proteins. Swabs collected from 2417 dabbling ducks and gulls in the south-west of Norway during five ordinary hunting seasons (August-December) in the period 2005-2010 were analyzed for presence of AIV. Multivariate linear regression was used to identify associations between AIV prevalence, host species and sampling time. Five AIVs from mallard (Anas platyrhynchos) (H3N8, H9N2) and common gull (H6N8, H13N2, H16N3) were full-length characterized and phylogenetically analyzed together with GenBank reference sequences. Low pathogenic AIVs were detected in 15.5% (CI: 14.1-17.0) of the samples. The overall AIV prevalence was lower in December compared to that found in August to November (p = 0.003). AIV was detected in 18.7% (CI: 16.8-20.6) of the dabbling ducks. A high AIV prevalence of 7.8% (CI; 5.9-10.0) was found in gulls. A similar temporal pattern in AIV prevalence was found in both bird groups. Thirteen hemagglutinin and eight neuraminidase subtypes were detected. No evidence of intercontinental reassortment was found. Eurasian avian (non H13 and H16) PB2 or PA genes were identified in five reference Eurasian gull (H13 and H16) AIV genomes from GenBank. The NA gene from the Norwegian H13N2 gull isolate was of Eurasian avian origin. The similar temporal pattern in AIV prevalence found in dabbling ducks and gulls, the relatively high virus prevalence detected in gulls and the evidence of

  15. Proteomic characterization of vanA-containing Enterococcus recovered from Seagulls at the Berlengas Natural Reserve, W Portugal.

    PubMed

    Radhouani, Hajer; Poeta, Patrícia; Pinto, Luís; Miranda, Júlio; Coelho, Céline; Carvalho, Carlos; Rodrigues, Jorge; López, María; Torres, Carmen; Vitorino, Rui; Domingues, Pedro; Igrejas, Gilberto

    2010-09-21

    Enterococci have emerged as the third most common cause of nosocomial infections, requiring bactericidal antimicrobial therapy. Although vancomycin resistance is a major problem in clinics and has emerged in an important extend in farm animals, few studies have examined it in wild animals. To determine the prevalence of vanA-containing Enterococcus strains among faecal samples of Seagulls (Larus cachinnans) of Berlengas Natural Reserve of Portugal, we developed a proteomic approach integrated with genomic data. The purpose was to detect the maximum number of proteins that vary in different enterococci species which are thought to be connected in some, as yet unknown, way to antibiotic resistance. From the 57 seagull samples, 54 faecal samples showed the presence of Enterococcus isolates (94.7%). For the enterococci, E. faecium was the most prevalent species in seagulls (50%), followed by E. faecalis and E. durans (10.4%), and E. hirae (6.3%). VanA-containing enterococcal strains were detected in 10.5% of the 57 seagull faecal samples studied. Four of the vanA-containing enterococci were identified as E. faecium and two as E. durans. The tet(M) gene was found in all five tetracycline-resistant vanA strains. The erm(B) gene was demonstrated in all six erythromycin-resistant vanA strains. The hyl virulence gene was detected in all four vanA-containing E. faecium isolates in this study, and two of them harboured the purK1 allele. In addition these strains also showed ampicillin and ciprofoxacin resistance. The whole-cell proteomic profile of vanA-containing Enterococcus strains was applied to evaluate the discriminatory power of this technique for their identification. The major differences among species-specific profiles were found in the positions corresponding to 97-45 kDa. Sixty individualized protein spots for each vanA isolate was identified and suitable for peptide mass fingerprinting measures by spectrometry measuring (MALDI/TOF MS) and their identification

  16. Proteomic characterization of vanA-containing Enterococcus recovered from Seagulls at the Berlengas Natural Reserve, W Portugal

    PubMed Central

    2010-01-01

    Background Enterococci have emerged as the third most common cause of nosocomial infections, requiring bactericidal antimicrobial therapy. Although vancomycin resistance is a major problem in clinics and has emerged in an important extend in farm animals, few studies have examined it in wild animals. To determine the prevalence of vanA-containing Enterococcus strains among faecal samples of Seagulls (Larus cachinnans) of Berlengas Natural Reserve of Portugal, we developed a proteomic approach integrated with genomic data. The purpose was to detect the maximum number of proteins that vary in different enterococci species which are thought to be connected in some, as yet unknown, way to antibiotic resistance. Results From the 57 seagull samples, 54 faecal samples showed the presence of Enterococcus isolates (94.7%). For the enterococci, E. faecium was the most prevalent species in seagulls (50%), followed by E. faecalis and E. durans (10.4%), and E. hirae (6.3%). VanA-containing enterococcal strains were detected in 10.5% of the 57 seagull faecal samples studied. Four of the vanA-containing enterococci were identified as E. faecium and two as E. durans. The tet(M) gene was found in all five tetracycline-resistant vanA strains. The erm(B) gene was demonstrated in all six erythromycin-resistant vanA strains. The hyl virulence gene was detected in all four vanA-containing E. faecium isolates in this study, and two of them harboured the purK1 allele. In addition these strains also showed ampicillin and ciprofoxacin resistance. The whole-cell proteomic profile of vanA-containing Enterococcus strains was applied to evaluate the discriminatory power of this technique for their identification. The major differences among species-specific profiles were found in the positions corresponding to 97-45 kDa. Sixty individualized protein spots for each vanA isolate was identified and suitable for peptide mass fingerprinting measures by spectrometry measuring (MALDI/TOF MS) and their

  17. Recommendations on the use of prescribed burning practices in grassland conservation - An evidence-based study from Hungary

    NASA Astrophysics Data System (ADS)

    Tóthmérész, Béla; Valkó, Orsolya; Török, Péter; Végvári, Zsolt; Deák, Balázs

    2015-04-01

    Fire as a natural disturbance has been present in most European grasslands. In parallel controlled use of burning was an important part of the traditional landscape management for millennia. It was used to reduce litter and suppress woody vegetation as well as to maintain open landscapes suitable for farming. Recently, human activities have a considerable impact on natural fire regimes through habitat fragmentation, cessation of traditional grassland management and climate change. Nowadays the majority of human-ignited fires are uncontrolled burnings and arson, which have serious negative impacts on human life, property and can be detrimental also from the nature conservation point of view. Despite fire was widely applied in the past and the considerable extension and frequency of current grassland fires, the impact of fire on the grassland biodiversity is still scarcely documented in Europe. The aim of our study was to gather practical knowledge and experiences from Hungary concerning the effects of fire on grasslands. To fulfil this aim we sent questionnaires to experts from Hungarian national park directorates to gather unpublished data and field observations concerning the effects of burning on grasslands. Based on the answers for the questionnaires fire regularly occur in almost every grassland types in Hungary. We found that effects of fire are habitat-specific. One hand uncontrolled burning and arson have serious detrimental impacts on many endangered species (ground-dwelling birds, such as Asio flammeus, Tringa totanus and Vanellus vanellus; or lizards, such as Ablepharus kitaibelii). On the other hand in several cases fire has a positive effect on the habitat structure and favours species of high nature conservation interest (plant species, such as Adonis volgensis, Chamaecytisus supinus and Pulsatilla grandis; butterflies, such as Euphydryas aurinia; bird species such as Circus aeruginosus and Larus cachinnans). Our results suggest that even uncontrolled

  18. Metals and radionuclides in birds and eggs from Amchitka and Kiska Islands in the Bering Sea/Pacific Ocean ecosystem.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2007-04-01

    Metals and radionuclide levels in marine birds of the Aleutians are of interest because they are part of subsistence diets of the Aleut people, and can also serve as indicators of marine pollution. We examined geographic and species-specific variations in concentrations of radionuclides in birds and their eggs from Amchitka, the site of underground nuclear tests from 1965 to 1971, and Kiska Islands (a reference site) in the Aleutians, and the levels of lead, mercury and cadmium in eggs. In 2004 we collected common eiders (Somateria mollissima), tufted puffins (Fratercula cirrhata), pigeon guillemot (Cepphus columba) and glaucous-winged gulls (Larus glaucescens) from Amchitka and Kiska, and eggs from eiders and gulls from the two island. We also collected one runt bald eagle (Haliaeetus leucocephalus) chick from both Amchitka and Kiska Islands. For most species, the levels of radionuclide isotopes were below the minimum detectable activity levels (MDA). Out of 74 cesium-137 analyses, only one composite (gulls) was above the MDA, and out of 14 composites tested for plutonium (Pu-239, 240), only one exceeded the MDA (a guillemots). Three composites out of 14 tested had detectable uranium-238. In all cases, the levels were low and close to the MDAs, and were below those reported for other seabirds. There were significant interspecific differences in metal levels in eggs: gulls had significantly higher levels of cadmium and mercury than the eiders, and eiders had higher levels of lead than gulls. There were few significant differences as a function of island, but eiders had significantly higher levels of cadmium in eggs from Kiska, and gulls had significantly higher levels of mercury on Kiska. The levels of cadmium and mercury in eggs of eiders and gulls from this study were above the median for cadmium and mercury from studies in the literature. The levels of mercury in eggs are within the range known to affect avian predators, but seabirds seem less vulnerable to

  19. Land or sea? Foraging area choice during breeding by an omnivorous gull.

    PubMed

    Isaksson, Natalie; Evans, Thomas J; Shamoun-Baranes, Judy; Åkesson, Susanne

    2016-01-01

    Generalist predators may vary their diet and use of habitat according to both internal state (e.g. breeding stage) and external (e.g. weather) factors. Lesser black-backed gulls Larus fuscus (Linnaeus 1758) are dietary generalists, foraging in both terrestrial and marine habitats during breeding. We investigate what affects the gulls' propensity to forage at sea or on land. We assess the importance of terrestrial foraging to gulls in the Baltic Sea (sub. sp. L. f. fuscus), looking especially at their use of agricultural fields. Through the GPS tracking of 19 individuals across 3 years we tracked 1038 foraging trips and found that 21.2 % of foraging trips were predominantly terrestrial, 9.0 % were a mix of terrestrial and marine, and 68.5 % were exclusively marine. Terrestrial trips were (1) more frequent when departing around sunrise, whereas marine trips occurred throughout the day. Additionally, trips with mostly land-based foraging decreased as the breeding season progressed, suggesting dietary switching coincident with the onset of chick provisioning. (2) During cloudy and cold conditions terrestrial foraging trips were more likely. (3) We found no differences between sexes in their land-based foraging strategy. (4) Gull individuals showed great variation in foraging strategy. Using observations of agricultural fields, carried out for one year, we found that (5) gulls preferentially foraged on fields with short vegetation, and there was a positive association with occurrence of waders and other species of gulls. (6) The availability and use of these preferred fields decreased through the breeding period. This study found high prevalence of terrestrial foraging during early breeding as well as support for dietary switching early in the breeding season. The overall tendency for marine or terrestrial foraging was consistent within individuals, with gull identity accounting for much of the variation observed in foraging trips. Our results suggest that

  20. Collision and displacement vulnerability among marine birds of the California Current System associated with offshore wind energy infrastructure

    USGS Publications Warehouse

    Adams, Josh; Kelsey, Emily C.; Felis, Jonathan J.; Pereksta, David M.

    2016-10-27

    With growing climate change concerns and energy constraints, there is an increasing need for renewable energy sources within the United States and globally. Looking forward, offshore wind-energy infrastructure (OWEI) has the potential to produce a significant proportion of the power needed to reach our Nation’s renewable energy goal. Offshore wind-energy sites can capitalize open areas within Federal waters that have persistent, high winds with large energy production potential. Although there are few locations in the California Current System (CCS) where it would be acceptable to build pilemounted wind turbines in waters less than 50 m deep, the development of technology able to support deep-water OWEI (>200 m depth) could enable wind-energy production in the CCS. As with all h