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Sample records for glaucous gulls larus

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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).

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 75 FR 29574 - Final Legislative Environmental Impact Statement for the Harvest of Glaucous-Winged Gull Eggs by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... Environmental Impact Statement for the Harvest of Glaucous-Winged Gull Eggs by the Huna Tlingit in Glacier Bay... Glacier Bay National Park. SUMMARY: The National Park Service (NPS) announces the availability of a final... Tlingit in Glacier Bay National Park. The document describes and analyzes the environmental impacts of...

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  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. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. 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...

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. Preliminary study of genetic diversity and population structure of the Relict Gull Larus relictus (Charadriiformes Laridae) using mitochondrial and nuclear genes.

    PubMed

    Yang, Chao; Lian, Ting; Wang, Qing-Xiong; Huang, Yuan; Xiao, Hong

    2016-11-01

    The genetic diversity and the population history of the Relict Gull (Larus relictus) were studied based on the sequences of two mitochondrial genes (Cyt b and ND2) and one nuclear gene (the third intron of the Z-linked muscle-specific kinase gene [MUSK]) from 47 individuals. The results showed that the population expresses very low genetic diversity while lacking large geographical population. Demographic history analysis suggested that population expansion might have been recent and that the average estimated expansion time of L. relictus is from 0.09 to 0.23 Ma BP. Whether the other three breeding subpopulations are involved in the Ordos breeding subpopulation, require further study with more effective molecular markers. The species is threatened by habitat loss and fragmentation, and actions to protect it are suggested to improve the population fragmentation of breeding.

  17. 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

  18. 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.

  19. 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.

  20. 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).

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 75 FR 71731 - Notice of Availability of the Record of Decision for the Harvest of Glaucous-Winged Gull Eggs by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ... Gull Eggs by Huna Tlingit in Glacier Bay National Park and Preserve Legislative Environmental Impact... Legislative Environmental Impact Statement. SUMMARY: The National Park Service (NPS) announces the availability of the Record of Decision (ROD) for the Legislative Environmental Impact Statement (LEIS) on...

  7. 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

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Sexing California gulls using morphometrics and discriminant function analysis

    USGS Publications Warehouse

    Herring, G.; Ackerman, J.T.; Eagles-Smith, C. A.; Takekawa, J.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.

  8. 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.

  9. 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.

  10. 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. 

  11. 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

  12. Hydrogen isotope composition of leaf wax n-alkanes in glaucous and non-glaucous varieties of wheat (Triticum spp.)

    NASA Astrophysics Data System (ADS)

    Pedentchouk, Nikolai; Eley, Yvette; Frizell-Armitage, Amelia; Uauy, Cristobal

    2015-04-01

    The use of the 2H/1H composition of terrestrial plants in climate and ecology studies depends on fundamental understanding of the processes within the plant that control fractionation of these two isotopes. Little is currently known about the extent of 2H/1H fractionation at different steps of biosynthesis, after the initial H uptake following leaf water photolysis. Knowing this effect is particularly important when seeking to interpret the 2H/1H composition of leaf wax biomarkers from plants that differ in the amount and type of individual compound classes in their leaf waxes. The purpose of this study was to investigate the link between the quantity and distribution of n-alkyl lipids in leaf waxes and their isotopic composition. We used a genetic approach to suppress glaucousness in 2 varieties of wheat (Alchemy and Malacca), which resulted in glaucous and non-glaucous phenotypes of both varieties. Both phenotypes were then grown outdoors under identical environmental conditions in central Norfolk, UK. At the end of the growing season, the plants were sampled for soil water, leaf water, and leaf wax isotopic measurements. Comparison of the leaf wax composition of the non-glaucous and glaucous phenotypes revealed that the non-glaucous varieties were characterised by the absence of diketones and a greater concentration of n-alkanes and primary alcohols.. Our results showed very small differences between glaucous and non-glaucous varieties with regard to soil (mean values, <2 per mil) and leaf (<1 per mil) water 2H/1H. Conversely, there was 15-20 and 10-15 per mil 2H-depletion in the C29 and C31 n-alkanes, respectively, from the non-glaucous phenotype. This 2H-depletion in the non-glaucous phenotype demonstrated that the suppression of diketone production and the increase in n-alkane and primary alcohol concentrations are linked with a shift in the 2H/1H composition of n-alkanes. The initial results of this work suggest that plants using the same environmental water

  13. 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.

  14. 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.

  15. Herring gulls and great black-backed gulls as indicators of contaminants in bald eagles in Lake Ontario, Canada.

    PubMed

    Weseloh, D Vaughn; Hughes, Kimberly D; Ewins, Peter J; Best, Dave; Kubiak, Timothy; Shieldcastle, Mark C

    2002-05-01

    In 2000, a pair of bald eagles (Haliaeetus leucocephalus) nested successfully along the shorelines of Lake Ontario in North America for the first time since 1957. However, it is a continuing question whether bald eagles will be able to reproduce successfully as they return to nest on Lake Ontario. Great black-backed gulls (Larus marinus) and herring gulls (L. argentatus) were selected as surrogate species to predict contaminant levels in eggs of bald eagles nesting on Lake Ontario. Because of the suspected overlap in the diets of great black-backed gulls and bald eagles (i.e., fish, gull chicks, and waterfowl), the two species probably occupy a similar trophic level in the Lake Ontario food web and, thus, may have similar contaminant levels. Fresh great black-backed gull and herring gull eggs were collected from three study sites in eastern Lake Ontario in 1993 and 1994 and analyzed for contaminants. Average contaminant levels of dichlorodiphenyldichloroethane (p,p'-DDE), total polychlorinated biphenyls (PCBs), and dieldrin in great black-backed gull eggs were 12.85, 26.27, and 0.27 microg/g, respectively. The mean ratio of contaminant levels in great black-backed gull eggs to contaminant levels in herring gull eggs for these three contaminants was 2.09 (range of means, 1.73-2.38). Predicted levels of contaminants in bald eagle eggs in Lake Ontario would be expected to be similar to the mean levels reported for great black-backed gull eggs. As a comparison, contaminant levels in bald eagle eggs collected from other Great Lakes nesting sites were compared to mean levels reported for herring gull eggs collected from nearby sites in 1986 to 1995. The mean ratio of contaminant levels in bald eagle eggs to contaminant levels in herring gull eggs from these sites for DDE, total PCBs, and dieldrin was 2.40 (range of means, 1.73-3.28). These ratios are very similar to those reported using great black-backed gull eggs, illustrating the apparent similarity in trophic status

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  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. 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.

  3. 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.

  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. 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. 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.

  7. 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.

  8. 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.

  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.

  10. Reductions in Gull Populations Improve Beachwater Quality.

    EPA Science Inventory

    BACKGROUND. Gulls are often cited as an important source of fecal pollution to surface waters, and fecal indicator bacteria (FIB) concentrations have been shown to be significantly correlated with gull populations. However, it is unclear whether gull contamination poses a risk to...

  11. 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.

  12. 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.

  13. 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.

  14. 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).

  15. 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.

  16. 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

  17. The early history of glaucoma: the glaucous eye (800 BC to 1050 AD)

    PubMed Central

    Leffler, Christopher T; Schwartz, Stephen G; Hadi, Tamer M; Salman, Ali; Vasuki, Vivek

    2015-01-01

    To the ancient Greeks, glaukos occasionally described diseased eyes, but more typically described healthy irides, which were glaucous (light blue, gray, or green). During the Hippocratic period, a pathologic glaukos pupil indicated a media opacity that was not dark. Although not emphasized by present-day ophthalmologists, the pupil in acute angle closure may appear somewhat green, as the mid-dilated pupil exposes the cataractous lens. The ancient Greeks would probably have described a (normal) green iris or (diseased) green pupil as glaukos. During the early Common Era, eye pain, a glaucous hue, pupil irregularities, and absence of light perception indicated a poor prognosis with couching. Galen associated the glaucous hue with a large, anterior, or hard crystalline lens. Medieval Arabic authors translated glaukos as zarqaa, which also commonly described light irides. Ibn Sina (otherwise known as Avicenna) wrote that the zarqaa hue could occur due to anterior prominence of the lens and could occur in an acquired manner. The disease defined by the glaucous pupil in antiquity is ultimately indeterminate, as the complete syndrome of acute angle closure was not described. Nonetheless, it is intriguing that the glaucous pupil connoted a poor prognosis, and came to be associated with a large, anterior, or hard crystalline lens. PMID:25673972

  18. The early history of glaucoma: the glaucous eye (800 BC to 1050 AD).

    PubMed

    Leffler, Christopher T; Schwartz, Stephen G; Hadi, Tamer M; Salman, Ali; Vasuki, Vivek

    2015-01-01

    To the ancient Greeks, glaukos occasionally described diseased eyes, but more typically described healthy irides, which were glaucous (light blue, gray, or green). During the Hippocratic period, a pathologic glaukos pupil indicated a media opacity that was not dark. Although not emphasized by present-day ophthalmologists, the pupil in acute angle closure may appear somewhat green, as the mid-dilated pupil exposes the cataractous lens. The ancient Greeks would probably have described a (normal) green iris or (diseased) green pupil as glaukos. During the early Common Era, eye pain, a glaucous hue, pupil irregularities, and absence of light perception indicated a poor prognosis with couching. Galen associated the glaucous hue with a large, anterior, or hard crystalline lens. Medieval Arabic authors translated glaukos as zarqaa, which also commonly described light irides. Ibn Sina (otherwise known as Avicenna) wrote that the zarqaa hue could occur due to anterior prominence of the lens and could occur in an acquired manner. The disease defined by the glaucous pupil in antiquity is ultimately indeterminate, as the complete syndrome of acute angle closure was not described. Nonetheless, it is intriguing that the glaucous pupil connoted a poor prognosis, and came to be associated with a large, anterior, or hard crystalline lens.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  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. 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

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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).

  10. Dramatic Improvements in Beach Water Quality Following Gull Removal

    EPA Science Inventory

    Gulls are often cited as important contributors of fecal contamination to surface waters, and some recreational beaches have used gull control measures to improve microbial water quality. In this study, gulls were chased from a Lake Michigan beach using specially trained dogs, a...

  11. Aerial estimation of the size of gull breeding colonies

    USGS Publications Warehouse

    Kadlec, J.A.; Drury, W.H.

    1968-01-01

    Counts on photographs and visual estimates of the numbers of territorial gulls are usually reliable indicators of the number of gull nests, but single visual estimates are not adequate to measure the number of nests in individual colonies. To properly interpret gull counts requires that several islands with known numbers of nests be photographed to establish the ratio of gulls to nests applicable for a given local census. Visual estimates are adequate to determine total breeding gull numbers by regions. Neither visual estimates nor photography will reliably detect annual changes of less than about 2.5 percent.

  12. 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

  13. 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.

  14. 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.

  15. Effects of oil transferred from incubating gulls to their eggs

    USGS Publications Warehouse

    King, K.A.; LeFever, C.A.

    1979-01-01

    No. 2 fuel oil, or water, was applied to the breast feathers of incubating laughing gulls trapped at their nest site on an island colony in Texas. Gulls were released after treatment and allowed to incubate their eggs for 5 days. Oil was transferred from the feathers of incubating adults to their eggs and resulted in 41% embryo mortality compared with 2% in controls.

  16. 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.

  17. Assessing gull abundance and food availability in urban parking lots

    USGS Publications Warehouse

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

    2015-01-01

    Feeding birds is a common activity throughout the world; yet, little is known about the extent of feeding gulls in urban areas. We monitored 8 parking lots in central Massachusetts, USA, during the fall and winter of 2011 to 2013 in 4 monitoring sessions to document the number of gulls present, the frequency of human–gull feeding interactions, and the effectiveness of signage and direct interaction in reducing human-provisioned food. Parking lots were divided between “education” and “no-education” lots. In education lots, we erected signs about problems caused when people feed birds and also asked people to stop feeding birds. We did not erect signs or ask people to stop feeding birds at no-education lots. We spent >1,200 hours in parking lots (range = 136 to 200 hours per parking lot), and gulls were counted every 20 minutes. We conducted >4,000 counts, and ring-billed gulls (Lorus delawarensis) accounted for 98% of all gulls. Our educational efforts were minimally effective. There were fewer feedings (P = 0.01) in education lots during one of the monitoring sessions but significantly more gulls (P = 0.008) in education lots during 2 monitoring sessions. While there was a marginal decrease (P = 0.055) in the number of feedings after no-education lots were transformed into education lots, there was no difference in gull numbers in these lots (P = 0.16). Education appears to have some influence in reducing the number of people feeding gulls, but our efforts were not able to reduce the number of human feeders or the amount of food enough to influence the number of gulls using parking lots.

  18. 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.

  19. 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.

  20. Aerodynamic implications of gull's drooped wing-tips.

    PubMed

    Andrews, S A; Perez, R E; Allan, W D E

    2013-12-01

    When in gliding flight, gulls are observed to adopt a drooped wing-tip configuration. This paper investigates whether this configuration might represent an aerodynamic optimum or if it is the result of constraints imposed by the gull's anatomy. A computational model was developed for the aerodynamic performance of a gull in gliding flight. This model was used in conjunction with both global and local optimizers to determine the most aerodynamically optimal configuration for cases where the gull was constrained to move its wing within its natural flapping cycle as well as when the wing had full freedom of motion. The results of this analysis determined the best wing configuration for a gull in gliding flight and demonstrated that such a configuration not only had the highest lift-to-drag ratio but also could be achieved within the constraints of the kinematics of the gull wing. These results are of interest outside studies of gulls, since the drooped wing-tip configuration could be relevant for new designs of small air vehicles.

  1. 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.

  2. 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.

  3. 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.

  4. Parathion alters incubation behavior of laughing gulls

    USGS Publications Warehouse

    White, D.H.; Mitchell, C.A.; Hill, E.F.

    1983-01-01

    One member of each pair of incubating laughing gulls at 9 nests was trapped, orally dosed with either 6 mg/kg parathion in corn oil or corn oil alone, and marked about the neck with red dye. Each nest was marked with a numbered stake and the treatment was recorded. A pilot study with captive laughing gulls had determined the proper dosage of parathion that would significantly inhibit their brain AChE activity (about 50% of normal) without overt signs of poisoning. After dosing, birds were released and the nests were observed for 2 1/2 days from a blind on the nesting island. The activities of the birds at each marked nest were recorded at 10-minute intervals. Results indicated that on the day of treatment there was no difference (P greater than 0.05, Chi-square test) in the proportion of time spent on the nest between treated and control birds. However, birds dosed with 6 mg/kg parathion spent significantly less time incubating on days 2 and 3 than did birds receiving only corn oil. By noon on the third day, sharing of nest duties between pair members in the treated group had approached normal, indicating recovery from parathion intoxication. These findings suggest that sublethal exposure of nesting birds to an organophosphate (OP) insecticide, such as parathion, may result in decreased nest attentiveness, thereby making the clutch more susceptible to predation or egg failure. Behavioral changes caused by sublethal OP exposure could be especially detrimental in avian species where only one pair member incubates or where both members are exposed in species sharing nest duties.

  5. Distribution of Gull Specific Molecular Marker in Coastal Areas of Lake Ontario

    EPA Science Inventory

    Gulls have been implicated as primary sources of fecal contamination in the Great Lakes, a fact that may have health implications due to the potential spread of microbial pathogens by waterfowl. To better understand the spatial variability of gull fecal contamination, a gull-spe...

  6. 77 FR 43805 - Gull Hazard Reduction Program at John F. Kennedy International Airport; Record of Decision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-26

    ...; ] DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service Gull Hazard Reduction Program at John F... environmental impact statement for the Gull Hazard Reduction Program at John F. Kennedy International Airport... around the John F. Kennedy International Airport. This action is a supplement to the Gull...

  7. 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

  8. GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast

    PubMed Central

    Stienen, Eric W.M.; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M.; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

    2016-01-01

    Abstract In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF). PMID:26877689

  9. GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast.

    PubMed

    Stienen, Eric W M; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

    2016-01-01

    In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF).

  10. Developmental Changes in Composition and Morphology of Cuticular Waxes on Leaves and Spikes of Glossy and Glaucous Wheat (Triticum aestivum L.).

    PubMed

    Wang, Yong; Wang, Jiahuan; Chai, Guaiqiang; Li, Chunlian; Hu, Yingang; Chen, Xinhong; Wang, Zhonghua

    2015-01-01

    The glossy varieties (A14 and Jing 2001) and glaucous varieties (Fanmai 5 and Shanken 99) of wheat (Triticum aestivum L.) were selected for evaluation of developmental changes in the composition and morphology of cuticular waxes on leaves and spikes. The results provide us with two different wax development patterns between leaf and spike. The general accumulation trend of the total wax load on leaf and spike surfaces is first to increase and then decrease during the development growth period, but these changes were caused by different compound classes between leaf and spike. Developmental changes of leaf waxes were mainly the result of variations in composition of alcohols and alkanes. In addition, diketones were the third important contributor to the leaf wax changes in the glaucous varieties. Alkanes and diketones were the two major compound classes that caused the developmental changes of spike waxes. For leaf waxes, β- and OH-β-diketones were first detected in flag leaves from 200-day-old plants, and the amounts of β- and OH-β-diketones were significantly higher in glaucous varieties compared with glossy varieties. In spike waxes, β-diketone existed in all varieties, but OH-β-diketone was detectable only in the glaucous varieties. Unexpectedly, the glaucous variety Fanmai 5 yielded large amounts of OH-β-diketone. There was a significant shift in the chain length distribution of alkanes between early stage leaf and flag leaf. Unlike C28 alcohol being the dominant chain length in leaf waxes, the dominant alcohol chain length of spikes was C24 or C26 depending on varieties. Epicuticular wax crystals on wheat leaf and glume were comprised of platelets and tubules, and the crystal morphology changed constantly throughout plant growth, especially the abaxial leaf crystals. Moreover, our results suggested that platelets and tubules on glume surfaces could be formed rapidly within a few days.

  11. 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.

  12. Phylogenetic Diversity and Molecular Detection of Bacteria in Gull Feces

    EPA Science Inventory

    In spite of increasing public health concerns about the potential risks associated with swimming in waters contaminated with waterfowl feces, little is known about the composition of the gut microbial community of aquatic birds. To address this, a gull 16S rDNA fecal clone librar...

  13. POTENTIAL FOR GULLS TO TRANSPORT BACTERIA FROM HUMAN WASTE SITES

    EPA Science Inventory

    This study was designed as a first step in assessing whether gulls visiting human waste sites can acquire human microorganisms and distribute them across the coastal landscape. Beaches, landfills, and a lagoon of treated wastewater located in a coastal Lake Michigan county were t...

  14. Structure of the New England herring gull population

    USGS Publications Warehouse

    Kadlec, J.A.; Drury, W.H.

    1968-01-01

    Measurements of the rates of population increase, reproduction, and mortality together with an observed age ratio, were used to analyze the population of the Herring Gull in New England. Data from sporadic censuses prior to this study, aerial censuses by the authors, and National Audubon Society Christmas Bird Count indicated that the New England breeding population has been doubling every 12 to 15 years since the early 1900's. This increase has involved founding new colonies and expanding the breeding range There is evidence that 15 to 30% of the adults do not breed in any given year. Sixty-one productivity measurements on 43 islands from 1963 through 1966, involving almost 13,000 nests, showed that from 0.8 to 1.4 young/breeding pair/year is the usual range of rate of production. The age distribution in the population was determined by classifying Herring Gulls by plumage category on an aerial census of the coast from Tampico, Mexico, to Cape Sable, Nova Scotia. Of the 622,000 gulls observed, 68% were adults, 17% were second- and third-year birds, and 15% were first-year birds. Mortality rates derived from band recovery data were too high to be consistent with the observed rate of population growth, productivity, and age structure. Loss of bands increasing to the rate of about 20%/year 5 years after banding eliminates most of the discrepancy. The age structure and rate of population increase indicate a mortality rate of 4 to 9% for gulls 2 years old or older, compared with the 25 to 30% indicated by band recoveries. The population structure we have developed fits everything we have observed about Herring Gull population dynamics, except mortality based on band recoveries.

  15. 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.

  16. Comparison of Gull Feces-Specific Assays Targeting the 16S rRNA Genes of Catellicoccus marimammalium and Streptococcus spp.

    PubMed Central

    Ryu, Hodon; Griffith, John F.; Khan, Izhar U. H.; Hill, Stephen; Edge, Thomas A.; Toledo-Hernandez, Carlos; Gonzalez-Nieves, Joel

    2012-01-01

    Two novel gull-specific quantitative PCR (qPCR) assays were developed using 16S rRNA gene sequences from gull fecal clone libraries: a SYBR green assay targeting Streptococcus spp. (gull3) and a hydrolysis TaqMan assay targeting Catellicoccus marimammalium (gull4). The objectives of this study were to compare the host specificity of a previous C. marimammalium qPCR assay (gull2) with that of the new markers and to examine the presence of the three gull markers in environmental water samples from different geographic locations. Most of the gull fecal samples tested (n = 255) generated positive signals with the gull2 and gull4 assays (i.e., >86%), whereas only 28% were positive with gull3. Low prevalence and abundance of tested gull markers (0.6 to 15%) were observed in fecal samples from six nonavian species (n = 180 fecal samples), whereas the assays cross-reacted to some extent (13 to 31%) with other (nongull) avian fecal samples. The gull3 assay was positive against fecal samples from 11 of 15 avian species, including gull. Of the presumed gull-impacted water samples (n = 349), 86%, 59%, and 91% were positive with the gull2, the gull3, and the gull4 assays, respectively. Approximately 5% of 239 non-gull-impacted water samples were positive with the gull2 and the gull4 assays, whereas 21% were positive witg the gull3 assay. While the relatively high occurrence of gull2 and gull4 markers in waters impacted by gull feces suggests that these assays could be used in environmental monitoring studies, the data also suggest that multiple avian-specific assays will be needed to accurately assess the contribution of different avian sources in recreational waters. PMID:22226950

  17. W3 Is a New Wax Locus That Is Essential for Biosynthesis of β-Diketone, Development of Glaucousness, and Reduction of Cuticle Permeability in Common Wheat

    PubMed Central

    Zhang, Zhengzhi; Wei, Wenjie; Zhu, Huilan; Challa, Ghana S.; Bi, Caili; Trick, Harold N.; Li, Wanlong

    2015-01-01

    The cuticle plays important roles in plant development, growth and defense against biotic and abiotic attacks. Crystallized epicuticular wax, the outermost layer of cuticle, is visible as white-bluish glaucousness. In crops like barley and wheat, glaucousness is trait of adaption to the dry and hot cultivation conditions, and hentriacontane-14,16-dione (β-diketone) and its hydroxy derivatives are the major and unique components of cuticular wax in the upper parts of adult plants. But their biosynthetic pathway and physiological role largely remain unknown. In the present research, we identified a novel wax mutant in wheat cultivar Bobwhite. The mutation is not allelic to the known wax production gene loci W1 and W2, and designated as W3 accordingly. Genetic analysis localized W3 on chromosome arm 2BS. The w3 mutation reduced 99% of β-diketones, which account for 63.3% of the total wax load of the wild-type. W3 is necessary for β-diketone synthesis, but has a different effect on β-diketone hydroxylation because the hydroxy-β-diketones to β-diketone ratio increased 11-fold in the w3 mutant. Loss of β-diketones caused failure to form glaucousness and significant increase of cuticle permeability in terms of water loss and chlorophyll efflux in the w3 mutant. Transcription of 23 cuticle genes from five functional groups was altered in the w3 mutant, 19 down-regulated and four up-regulated, suggesting a possibility that W3 encodes a transcription regulator coordinating expression of cuticle genes. Biosynthesis of β-diketones in wheat and their implications in glaucousness formation and drought and heat tolerance were discussed. Key Message W3 is essential for β-diketone biosynthesis but suppresses its hydroxylation. Loss-of-function mutation w3 significantly increased cuticle permeability in terms of water loss and chlorophyll efflux. PMID:26468648

  18. True navigation in migrating gulls requires intact olfactory nerves

    PubMed Central

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

    2015-01-01

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

  19. Comparison of gull-specific assays targeting 16S rRNA gene of Catellicoccus marimammalium and Streptococcus spp.

    EPA Science Inventory

    Gulls have been implicated as a source of fecal contamination in inland and coastal waters. Only one gull-specific assay is currently available (i.e., gull2 qPCR assay). This assay is based on the 16S rRNA gene of Catellicocclls marimammalium and has showed a high level of host-s...

  20. Bacteroidales diversity in ring-billed gulls (Laurus delawarensis) residing at Lake Michigan beaches.

    PubMed

    Jeter, Sonja N; McDermott, Colleen M; Bower, Patricia A; Kinzelman, Julie L; Bootsma, Melinda J; Goetz, Giles W; McLellan, Sandra L

    2009-03-01

    This study investigated the occurrence and diversity of Bacteroidales fecal bacteria in gulls residing in the Great Lakes region. Members of this bacterial order have been widely employed as human and bovine host-specific markers of fecal pollution; however, few studies have focused on gulls, which can be a major source of fecal indicator bacteria and pathogens at beaches. We found a low but consistent occurrence of Bacteroidales in gulls at five beaches in three different counties spanning the Wisconsin shoreline of Lake Michigan. The percentages of gulls positive for Bacteroidales were 4 to 8% at beaches in the southern part of the state and 8 to 50% at beaches in the north. Sequencing of 931 clones from seven gull Bacteroidales 16S rRNA gene libraries revealed a large amount of diversity in both individual and pooled gull fecal samples. Two libraries constructed from pooled gull fecal samples (n = 5 and n = 6) did not have a greater richness of sequences than individual samples, suggesting that even within a single gull diversity is high and an extensive sequencing effort is needed to characterize the populations. Estimates of the numbers of operational taxonomic units (OTUs) for the libraries obtained using different similarity levels revealed a large amount of microdiveristy with a limited number of OTUs at the 95% similarity level. Gull sequences were clustered by the beach from which they were collected, suggesting that there were geographic effects on the distribution of Bacteriodales. More than 53% of the 16S rRNA gene sequences from gulls at the southern beaches were associated with the family Porphyromonadaceae, primarily the genus Parabacteroides, whereas sequences from gulls at the northern beaches were comprised of Bacteroidaceae and Prevotellaceae sequences. Comparison of gull sequences with sequences from goose, canine, raccoon, and sewage sources revealed distinct clusters of closely related gull sequences; however, these sequences were widely

  1. Opportunistic fungal pathogen Candida glabrata circulates between humans and yellow-legged gulls

    PubMed Central

    Al-Yasiri, Mohammed Hashim; Normand, Anne-Cécile; L’Ollivier, Coralie; Lachaud, Laurence; Bourgeois, Nathalie; Rebaudet, Stanislas; Piarroux, Renaud; Mauffrey, Jean-François; Ranque, Stéphane

    2016-01-01

    The opportunistic pathogenic yeast Candida glabrata is a component of the mycobiota of both humans and yellow-legged gulls that is prone to develop fluconazole resistance. Whether gulls are a reservoir of the yeast and facilitate the dissemination of human C. glabrata strains remains an open question. In this study, MLVA genotyping highlighted the lack of genetic structure of 190 C. glabrata strains isolated from either patients in three hospitals or fecal samples collected from gull breeding colonies located in five distinct areas along the French Mediterranean littoral. Fluconazole-resistant isolates were evenly distributed between both gull and human populations. These findings demonstrate that gulls are a reservoir of this species and facilitate the diffusion of C. glabrata and indirect transmission to human or animal hosts via environmental contamination. This eco-epidemiological view, which can be applied to other vertebrate host species, broadens our perspective regarding the reservoirs and dissemination patterns of antifungal-resistant human pathogenic yeast. PMID:27782182

  2. Opportunistic fungal pathogen Candida glabrata circulates between humans and yellow-legged gulls.

    PubMed

    Al-Yasiri, Mohammed Hashim; Normand, Anne-Cécile; L'Ollivier, Coralie; Lachaud, Laurence; Bourgeois, Nathalie; Rebaudet, Stanislas; Piarroux, Renaud; Mauffrey, Jean-François; Ranque, Stéphane

    2016-10-26

    The opportunistic pathogenic yeast Candida glabrata is a component of the mycobiota of both humans and yellow-legged gulls that is prone to develop fluconazole resistance. Whether gulls are a reservoir of the yeast and facilitate the dissemination of human C. glabrata strains remains an open question. In this study, MLVA genotyping highlighted the lack of genetic structure of 190 C. glabrata strains isolated from either patients in three hospitals or fecal samples collected from gull breeding colonies located in five distinct areas along the French Mediterranean littoral. Fluconazole-resistant isolates were evenly distributed between both gull and human populations. These findings demonstrate that gulls are a reservoir of this species and facilitate the diffusion of C. glabrata and indirect transmission to human or animal hosts via environmental contamination. This eco-epidemiological view, which can be applied to other vertebrate host species, broadens our perspective regarding the reservoirs and dissemination patterns of antifungal-resistant human pathogenic yeast.

  3. Comparison of Gull Feces-specific Assays Targeting the 16S rRNA Gene of Catellicoccus Marimammalium and Streptococcus spp.

    EPA Science Inventory

    Two novel gull-specific qPCR assays were developed using 16S rRNA gene sequences from gull fecal clone libraries: a SYBR-green-based assay targeting Streptococcus spp. (i.e., gull3) and a TaqMan qPCR assay targeting Catellicoccus marimammalium (i.e., gull4). The main objectives ...

  4. 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.

  5. 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.

  6. Identification of novel quantitative trait loci for days to ear emergence and flag leaf glaucousness in a bread wheat (Triticum aestivum L.) population adapted to southern Australian conditions.

    PubMed

    Bennett, Dion; Izanloo, Ali; Edwards, James; Kuchel, Haydn; Chalmers, Ken; Tester, Mark; Reynolds, Matthew; Schnurbusch, Thorsten; Langridge, Peter

    2012-03-01

    In southern Australia, where the climate is predominantly Mediterranean, achieving the correct flowering time in bread wheat minimizes the impact of in-season cyclical and terminal drought. Flag leaf glaucousness has been hypothesized as an important component of drought tolerance but its value and genetic basis in locally adapted germplasm is unknown. From a cross between Kukri and RAC875, a doubled-haploid (DH) population was developed. A genetic linkage map consisting of 456 DArT and SSR markers was used to detect QTL affecting time to ear emergence and Zadoks growth score in seven field experiments. While ear emergence time was similar between the parents, there was significant transgressive segregation in the population. This was the result of segregation for the previously characterized Ppd-D1a and Ppd-B1 photoperiod responsive alleles. QTL of smaller effect were also detected on chromosomes 1A, 4A, 4B, 5A, 5B, 7A and 7B. A novel QTL for flag leaf glaucousness of large, repeatable effect was detected in six field experiments, on chromosome 3A (QW.aww-3A) and accounted for up to 52 percent of genetic variance for this trait. QW.aww-3A was validated under glasshouse conditions in a recombinant inbred line population from the same cross. The genetic basis of time to ear emergence in this population will aid breeders' understanding of phenological adaptation to the local environment. Novel loci identified for flag leaf glaucousness and the wide phenotypic variation within the DH population offers considerable scope to investigate the impact and value of this trait for bread wheat production in southern Australia.

  7. Spatio-temporal structure of hooded gull flocks.

    PubMed

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Hayakawa, Yoshinori

    2013-01-01

    We analyzed the spatio-temporal structure of hooded gull flocks with a portable stereo camera system. The 3-dimensional positions of individuals were reconstructed from pairs of videos. The motions of each individual were analyzed, and both gliding and flapping motions were quantified based on the velocity time series. We analyzed the distributions of the nearest neighbor's position in terms of coordinates based on each individual's motion. The obtained results were consistent with the aerodynamic interaction between individuals. We characterized the leader-follower relationship between individuals by a delay time to mimic the direction of a motion. A relation between the delay time and a relative position was analyzed quantitatively, which suggested the basic properties of the formation flight that maintains order in the flock.

  8. Diets of nestling Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Eyler, T.B.; Hatfield, J.S.; McGary, S.

    1998-01-01

    We studied the diets of nestling Gull-billed Terns (Sterna nilotica) at colonies in coastal Virginia during the breeding seasons of 1995 and 1996 as part of a long-term study of the species. No previous quantitative assessments had been made of diets of this species anywhere along the Atlantic Coast, and only a few observations had been reported from other coastal areas in the southern United States. During 80 h of observations over the two seasons, 757 feeding observations were made, primarily at two colony sites. We examined how prey type (fish, marine invertebrates, terrestrial prey) and size were influenced by year, tide cycle, season (early and late) and age of the young (small chicks 7 d). We did not find significant year differences, but all other factors revealed statistically significant results. Older (>7 d) chicks were fed relatively more terrestrial and marine invertebrate prey than were younger chicks. In June (early season), fewer fish and terrestrial prey were fed to chicks than later (July-August). Most prey were less than one bill length in size, with the majority of the smallest prey being marine invertebrates. Tide cycle influenced prey delivered with terrestrial prey becoming relatively more important during high and ebb periods than during low and flood tides when aquatic prey dominated. The major marine invertebrate prey taken was the fiddler crab (Uca spp.). Terrestrial prey consisted mostly of large odonates and orthopterans. Unlike earlier reports from Europe, we found no regurgitated food pellets in any of the colonies in either year. This study confirms that the Gull-billed Tern is an extremely opportunistic feeder and has adapted to a variety of habitats, helping to explain its cosmopolitan distribution.

  9. Diets of nestling gull-billed terns in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Eyler, T.B.; Hatfield, J.S.; McGary, S.

    1998-01-01

    We studied the diets of nestling Gull-billed Terns (Sterna nilotica) at colonies in coastal Virginia during the breeding seasons of 1995 and 1996 as part of a long-term study of the species. No previous quantitative assessments had been made of diets of this species anywhere along the Atlantic Coast, and only a few observations had been reported from other coastal areas in the southern United States. During 80 h of observations over the two seasons, 757 feeding observations were made, primarily at two colony sites. We examined how prey type (fish, marine invertebrates, terrestrial prey) and size were influenced by year, tide cycle, season (early and late) and age of the young (small chicks 7 d). We did not find significant year differences, but all other factors revealed statistically significant results. Older (>7 d) chicks were fed relatively more terrestrial and marine invertebrate prey than were younger chicks. In June (early season), fewer fish and terrestrial prey were fed to chicks than later (July-August). Most prey were less than one bill length in size, with the majority of the smallest prey being marine invertebrates. Tide cycle influenced prey delivered with terrestrial prey becoming relatively more important during high and ebb periods than during low and flood tides when aquatic prey dominated. The major marine invertebrate prey taken was the fiddler crab (Uca spp.). Terrestrial prey consisted mostly of large odonates and orthopterans. Unlike earlier reports from Europe, we found no regurgitated food pellets in any of the colonies in either year. This study confirms that the Gull-billed Tern is an extremely opportunistic feeder and has adapted to a variety of habitats, helping to explain its cosmopolitan distribution.

  10. Quantifying fall migration of Ross's gulls (Rhodostethia rosea) past Point Barrow, Alaska

    USGS Publications Warehouse

    Uher-Koch, Brian D.; Davis, Shanti E.; Maftei, Mark; Gesmundo, Callie; Suydam, R.S.; Mallory, Mark L.

    2014-01-01

    The Ross's gull (Rhodostethia rosea) is a poorly known seabird of the circumpolar Arctic. The only place in the world where Ross's gulls are known to congregate is in the near-shore waters around Point Barrow, Alaska where they undertake an annual passage in late fall. Ross's gulls seen at Point Barrow are presumed to originate from nesting colonies in Siberia, but neither their origin nor their destination has been confirmed. Current estimates of the global population of Ross's gulls are based largely on expert opinion, and the only reliable population estimate is derived from extrapolations from previous counts conducted at Point Barrow, but these data are now over 25 years old. In order to update and clarify the status of this species in Alaska, our study quantified the timing, number, and flight direction of Ross's gulls passing Point Barrow in 2011. We recorded up to two-thirds of the estimated global population of Ross's gulls (≥ 27,000 individuals) over 39 days with numbers peaking on 16 October when we observed over 7,000 birds during a three-hour period.

  11. Genetic Interactions Underlying the Biosynthesis and Inhibition of β-Diketones in Wheat and Their Impact on Glaucousness and Cuticle Permeability

    PubMed Central

    Zhang, Zhengzhi; Wang, Wei; Li, Wanlong

    2013-01-01

    Cuticular wax composition greatly impacts plant responses to dehydration. Two parallel pathways exist in Triticeae for manipulating wax composition: the acyl elongation, reduction, and decarbonylation pathway that is active at the vegetative stage and yields primary alcohols and alkanes, and the β-diketone pathway that predominates at the reproductive stage and synthesizes β-diketones. Variation in glaucousness during the reproductive stage of wheat is mainly controlled by the wax production genes, W1 and W2, and wax inhibitor genes, Iw1 and Iw2. Little is known about the metabolic and physiological effects of the genetic interactions among these genes and their roles in shifting wax composition during plant development. We characterized the effect of W1, W2, Iw1, and Iw2 and analyzed their interaction using a set of six near-isogenic lines (NILs) by metabolic, molecular and physiological approaches. Loss of functional alleles of both W genes or the presence of either Iw gene depletes β-diketones and results in the nonglaucous phenotype. Elimination of β-diketones is compensated for by an increase in aldehydes and primary alcohols in the Iw NILs. Accordingly, transcription of CER4-6, which encodes an alcohol-forming fatty acyl-CoA reductase, was elevated 120-fold in iw1Iw2. CER4-6 was transcribed at much higher levels in seedlings than in adult plants, and showed little difference between the glaucous and nonglaucous NILs, suggesting that Iw2 counteracts the developmental repression of CER4-6 at the reproductive stage. While W1 and W2 redundantly function in β-diketone biosynthesis, a combination of both functional alleles led to the β-diketone hydroxylation. Consistent with this, transcription of MAH1-9, which encodes a mid-chain alkane hydroxylase, increased seven-fold only in W1W2. In parallel with the hydroxyl-β-diketone production patterns, glaucousness was intensified and cuticle permeability was reduced significantly in W1W2 compared to the other NILs

  12. Genetic interactions underlying the biosynthesis and inhibition of β-diketones in wheat and their impact on glaucousness and cuticle permeability.

    PubMed

    Zhang, Zhengzhi; Wang, Wei; Li, Wanlong

    2013-01-01

    Cuticular wax composition greatly impacts plant responses to dehydration. Two parallel pathways exist in Triticeae for manipulating wax composition: the acyl elongation, reduction, and decarbonylation pathway that is active at the vegetative stage and yields primary alcohols and alkanes, and the β-diketone pathway that predominates at the reproductive stage and synthesizes β-diketones. Variation in glaucousness during the reproductive stage of wheat is mainly controlled by the wax production genes, W1 and W2, and wax inhibitor genes, Iw1 and Iw2. Little is known about the metabolic and physiological effects of the genetic interactions among these genes and their roles in shifting wax composition during plant development. We characterized the effect of W1, W2, Iw1, and Iw2 and analyzed their interaction using a set of six near-isogenic lines (NILs) by metabolic, molecular and physiological approaches. Loss of functional alleles of both W genes or the presence of either Iw gene depletes β-diketones and results in the nonglaucous phenotype. Elimination of β-diketones is compensated for by an increase in aldehydes and primary alcohols in the Iw NILs. Accordingly, transcription of CER4-6, which encodes an alcohol-forming fatty acyl-CoA reductase, was elevated 120-fold in iw1Iw2. CER4-6 was transcribed at much higher levels in seedlings than in adult plants, and showed little difference between the glaucous and nonglaucous NILs, suggesting that Iw2 counteracts the developmental repression of CER4-6 at the reproductive stage. While W1 and W2 redundantly function in β-diketone biosynthesis, a combination of both functional alleles led to the β-diketone hydroxylation. Consistent with this, transcription of MAH1-9, which encodes a mid-chain alkane hydroxylase, increased seven-fold only in W1W2. In parallel with the hydroxyl-β-diketone production patterns, glaucousness was intensified and cuticle permeability was reduced significantly in W1W2 compared to the other NILs

  13. 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.

  14. Evolution of a reassortant North American gull influenza virus lineage: drift, shift and stability

    USGS Publications Warehouse

    Hall, Jeffrey S.; TeSlaa, Joshua L.; Nashold, Sean W.; Halpin, Rebecca A.; Stockwell, Timothy; Wentworth, David E.; Dugan, Vivien; Ip, Hon S.

    2013-01-01

    Background: The role of gulls in the ecology of avian influenza (AI) is different than that of waterfowl. Different constellations of subtypes circulate within the two groups of birds and AI viruses isolated from North American gulls frequently possess reassortant genomes with genetic elements from both North America and Eurasian lineages. A 2008 isolate from a Newfoundland Great Black-backed Gull contained a mix of North American waterfowl, North American gull and Eurasian lineage genes. Methods: We isolated, sequenced and phylogenetically compared avian influenza viruses from 2009 Canadian wild birds. Results: We analyzed six 2009 virus isolates from Canada and found the same phylogenetic lineage had persisted over a larger geographic area, with an expanded host range that included dabbling and diving ducks as well as gulls. All of the 2009 virus isolates contained an internal protein coding set of genes of the same Eurasian lineage genes except PB1 that was from a North American lineage, and these genes continued to evolve by genetic drift. We show evidence that the 2008 Great Black-backed Gull virus was derived from this lineage with a reassortment of a North American PA gene into the more stable core set of internal protein coding genes that has circulated in avian populations for at least 2 years. From this core, the surface glycoprotein genes have switched several times creating H13N6, H13N2, and H16N3 subtypes. These gene segments were from North American lineages except for the H16 and N3 vRNAs. Conclusions: This process appears similar to genetic shifts seen with swine influenza where a stable "triple reassortant internal gene" core has circulated in swine populations with genetic shifts occurring with hemaggluttinin and neuraminidase proteins getting periodically switched. Thus gulls may serve as genetic mixing vessels for different lineages of avian influenza, similar to the role of swine with regards to human influenza. These findings illustrate the

  15. Watershed Assessment with Beach Microbial Source Tracking and Outcomes of Resulting Gull Management.

    PubMed

    Goodwin, Kelly D; Gruber, Steve; Vondrak, Mary; Crumpacker, Andrea

    2016-09-20

    Total maximum daily load (TMDL) implementation at a southern California beach involved ultraviolet treatment of watershed drainage that provided >97% reduction in fecal indicator bacteria (FIB) concentrations. However, this pollutant control measure did not provide sufficient improvement of beach water quality, prompting further assessment. Investigation included microbial source tracking (MST) for human, gull, and canine fecal sources, monitoring of enterococci and fecal coliform, and measurement of chemical and physical water quality parameters for samples collected from watershed, groundwater, and beach sites, including a beach scour pond and tidal creek. FIB variability remained poorly modeled in regression analysis. However, MST revealed correlations between FIB and gull source tracking markers, leading to recommendations to manage gulls as a pollutant source. Beach conditions were followed for three years after implementation of a best management practice (BMP) to abate gulls using a falconry program for the beach and an upland landfill. The gull abatement BMP was associated with improved beach water quality, and this appears to be the first report of falconry in the context of TMDL implementation. Overall, MST data enabled management action despite an inability to fully model FIB dynamics in the coupled watershed-beach system.

  16. Functional Metagenomics Reveals Previously Unrecognized Diversity of Antibiotic Resistance Genes in Gulls

    PubMed Central

    Martiny, Adam C.; Martiny, Jennifer B. H.; Weihe, Claudia; Field, Andrew; Ellis, Julie C.

    2011-01-01

    Wildlife may facilitate the spread of antibiotic resistance (AR) between human-dominated habitats and the surrounding environment. Here, we use functional metagenomics to survey the diversity and genomic context of AR genes in gulls. Using this approach, we found a variety of AR genes not previously detected in gulls and wildlife, including class A and C β-lactamases as well as six tetracycline resistance gene types. An analysis of the flanking sequences indicates that most of these genes are present in Enterobacteriaceae and various Gram-positive bacteria. In addition to finding known gene types, we detected 31 previously undescribed AR genes. These undescribed genes include one most similar to an uncharacterized gene in Verrucomicrobium and another to a putative DNA repair protein in Lactobacillus. Overall, the study more than doubled the number of clinically relevant AR gene types known to be carried by gulls or by wildlife in general. Together with the propensity of gulls to visit human-dominated habitats, this high diversity of AR gene types suggests that gulls could facilitate the spread of AR. PMID:22347872

  17. Distribution and potential significance of a gull fecal marker in urban coastal and riverine areas of southern Ontario, Canada

    EPA Science Inventory

    To better understand the distribution of gull fecal contamination in urban areas of southern Ontario, we used a gull-targeted PCR assay against 1309 water samples collected from 15 urban coastal and riverine locations during 2007. Approximately, 58 % of the water samples tested w...

  18. 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.

  19. A Communicative Analysis of Chekhovian Drama as Portrayed in "The Sea Gull."

    ERIC Educational Resources Information Center

    Hellweg, John D.; Hellweg, Susan A.

    The precision and poetic logic of the language used by Anton Chekhov in his plays, particularly "The Sea Gull," can be explored through an analysis of his use of dialogue, characterization, and imagery. Measuring the nature of a relationship, rather than providing a direct literal interchange, the dialogue is both social, when individual…

  20. No. 2 fuel oil decreases embryonic survival of great black-backed gulls

    USGS Publications Warehouse

    Coon, N.C.; Albers, P.H.; Szaro, R.C.

    1979-01-01

    Field study of the effects of No. 2 fuel oil applications to the eggs of great black-backed gulls on an island off the coast of Maine. Fuel oil applied in amounts of either 5 or 20 ul. All eggs opened 8 da later. Measured survival and estimated age of embryo at time of egg oiling.

  1. Comparative susceptibility of waterfowl and gulls to highly pathogenic avian influenza H5N1 virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild avian species in the Orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shorebirds) have traditionally been considered the natural reservoirs for avian influenza viruses (AIV) and morbidity or mortality is rarely associated with AIV infection in these hosts. However, ...

  2. Aspects of chick growth in Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Eyler, T.B.; Stotts, D.B.; Hatfield, J.S.

    1999-01-01

    Because of concerns about apparent population declines and low productivity of Gull-billed Terns (Sterna nilotica) along the coast of Virginia, we investigated whether food limitations may result in retarded growth rates of young. Several colonies of Gull-billed Terns were monitored from May to July each year from 1994 to 1996 on both sandy barrier islands and marsh/shellpile islands in coastal Virginia. Nests were visited one to three times a week to monitor clutch size and hatching success, and enclosures were installed around selected nests to monitor chick growth from hatching to at least two weeks of age. When comparing chick growth, we found significant year, habitat and hatch order effects. Chicks from marsh shellpiles had higher mass and culmen growth rates than did those from barrier islands, and first-hatched (A) chicks had significantly higher culmen growth rates than did second-hatched (B) chicks. Year effects were only found for mass growth rates. Growth rates of Gull- billed Terns in these Virginia colonies seem to be low relative to those of six other North American tern species from other geographic areas. These findings suggest that growth rates of young Gull-billed Terns, as well as other reproductive parameters, need to be examined in detail in other coastal areas such as Texas, where the species is more abundant, to determine whether our growth results are species- or region-specific.

  3. 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.

  4. Distribution Patterns Predict Individual Specialization in the Diet of Dolphin Gulls

    PubMed Central

    Masello, Juan F.; Wikelski, Martin; Voigt, Christian C.; Quillfeldt, Petra

    2013-01-01

    Many animals show some degree of individual specialization in foraging strategies and diet. This has profound ecological and evolutionary implications. For example, populations containing diverse individual foraging strategies will respond in different ways to changes in the environment, thus affecting the capacity of the populations to adapt to environmental changes and to diversify. However, patterns of individual specialization have been examined in few species. Likewise it is usually unknown whether specialization is maintained over time, because examining the temporal scale at which specialization occurs can prove difficult in the field. In the present study, we analyzed individual specialization in foraging in Dolphin Gulls Leucophaeus scoresbii, a scavenger endemic to the southernmost coasts of South America. We used GPS position logging and stable isotope analyses (SIA) to investigate individual specialization in feeding strategies and their persistence over time. The analysis of GPS data indicated two major foraging strategies in Dolphin Gulls from New I. (Falkland Is./Islas Malvinas). Tagged individuals repeatedly attended either a site with mussel beds or seabird and seal colonies during 5 to 7 days of tracking. Females foraging at mussel beds were heavier than those foraging at seabird colonies. Nitrogen isotope ratios (δ15N) of Dolphin Gull blood cells clustered in two groups, showing that individuals were consistent in their preferred foraging strategies over a period of at least several weeks. The results of the SIA as well as the foraging patterns recorded revealed a high degree of specialization for particular feeding sites and diets by individual Dolphin Gulls. Individual differences in foraging behavior were not related to sex. Specialization in Dolphin Gulls may be favored by the advantages of learning and memorizing optimal feeding locations and behaviors. Specialized individuals may reduce search and handling time and thus, optimize their

  5. Living on the Edge: Demography of the Slender-Billed Gull in the Western Mediterranean

    PubMed Central

    Sanz-Aguilar, Ana; Tavecchia, Giacomo; Afán, Isabel; Ramírez, Francisco; Doxa, Aggeliki; Bertolero, Albert; Gutiérrez-Expósito, Carlos; Forero, Manuela G.; Oro, Daniel

    2014-01-01

    Small and peripheral populations are typically vulnerable to local extinction processes but important for the metapopulation dynamics of species. The Slender-billed gull (Chroicocephalus genei) is a long-lived species breeding in unstable ephemeral coastal habitats. Their Western Mediterranean populations are relatively small and represent the edge of their global geographical distribution. At a local scale, using long-term data (14 years) on annual breeding success and capture-resights of marked individuals, we estimated and compared the vital rates and evaluated the connectivity of two Spanish populations (Ebro Delta and Doñana) varying in their local environmental conditions. At a metapopulation scale, we analyzed 22 years of data on breeding numbers to predict their future prospects by means of population demographic models. Local survival and breeding success of gulls from the Ebro Delta was lower than those from Doñana, which is likely the result of higher permanent emigration and/or winter mortality in the former. Gulls from the Ebro Delta wintered mostly in Mediterranean areas whereas those from Doñana did so in Atlantic coasts, where food availability is higher. Whereas adult local survival was constant, juvenile local survival showed temporal parallel variations between colonies, probably related to natal dispersal to other breeding colonies. Our results suggested that dispersal was higher at the Ebro Delta and gulls emigrating from their natal colonies settled preferentially in close patches. We found large fluctuations in breeding numbers among local populations probably related to the fact that the Slender-billed gull is a species adapted to unstable and unpredictable habitats with high abilities to disperse between suitable patches depending on environmental stochastic conditions during breeding. PMID:24664115

  6. Abundance and characteristics of the recreational water quality indicator bacteria Escherichia coli and enterococci in gull faeces

    USGS Publications Warehouse

    Fogarty, L.R.; Haack, S.K.; Wolcott, M.J.; Whitman, R.L.

    2003-01-01

    Aims: To evaluate the numbers and selected phenotypic and genotypic characteristics of the faecal indicator bacteria Escherichia coli and enterococci in gull faeces at representative Great Lakes swimming beaches in the United States. Methods and Results: E. coli and enterococci were enumerated in gull faeces by membrane filtration. E. coli genotypes (rep-PCR genomic profiles) and E. coli (Vitek?? GNI+) and enterococci (API?? rapid ID 32 Strep and resistance to streptomycin, gentamicin, vancomycin, tetracycline and ampicillin) phenotypes were determined for isolates obtained from gull faeces both early and late in the swimming season. Identical E. coli genotypes were obtained only from single gull faecal samples but most faecal samples yielded more than one genotype (median of eight genotypes for samples with 10 isolates). E. coli isolates from the same site that clustered at ???85% similarity were from the same sampling date and shared phenotypic characteristics, and at this similarity level there was population overlap between the two geographically isolated beach sites. Enterococcus API?? profiles varied with sampling date. Gull enterococci displayed wide variation in antibiotic resistance patterns, and high-level resistance to some antibiotics. Conclusions: Gull faeces could be a major contributor of E. coli (105-109 CFU g-1) and enterococci (104-108 CFU g-1) to Great Lakes recreational waters. E. coli and enterococci in gull faeces are highly variable with respect to their genotypic and phenotypic characteristics and may exhibit temporal or geographic trends in these features. Significance and Impact of the Study: The high degree of variation in genotypic or phenotypic characteristics of E. coli or enterococci populations within gull hosts will require extensive sampling for adequate characterization, and will influence methods that use these characteristics to determine faecal contamination sources for recreational waters.

  7. 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

  8. Attractiveness of Shredded Garbage to Gulls and Other Avian Species Potentially Hazardous to Aircraft

    DTIC Science & Technology

    1980-02-01

    attractiveness of shredded garbage as a food source for birds; and (2) to determine what changes have occurred in gull popula- tions and movement...feeders, not all regu- larly use garbage as their main food source . Those species that do feed on refuse, however, are involved in about 40 percent of...species Iarge enough to prov e a significant food source for birds. And, as expected, these were the only insects found in food samples taken from

  9. Rapidly increasing methyl mercury in endangered ivory gull (Pagophila eburnea) feathers over a 130 year record.

    PubMed

    Bond, Alexander L; Hobson, Keith A; Branfireun, Brian A

    2015-04-22

    Mercury (Hg) is increasing in marine food webs, especially at high latitudes. The bioaccumulation and biomagnification of methyl mercury (MeHg) has serious effects on wildlife, and is most evident in apex predators. The MeHg body burden in birds is the balance of ingestion and excretion, and MeHg in feathers is an effective indicator of overall MeHg burden. Ivory gulls (Pagophila eburnea), which consume ice-associated prey and scavenge marine mammal carcasses, have the highest egg Hg concentrations of any Arctic bird, and the species has declined by more than 80% since the 1980s in Canada. We used feathers from museum specimens from the Canadian Arctic and western Greenland to assess whether exposure to MeHg by ivory gulls increased from 1877 to 2007. Based on constant feather stable-isotope (δ(13)C, δ(15)N) values, there was no significant change in ivory gulls' diet over this period, but feather MeHg concentrations increased 45× (from 0.09 to 4.11 µg g(-1) in adults). This dramatic change in the absence of a dietary shift is clear evidence of the impact of anthropogenic Hg on this high-latitude threatened species. Bioavailable Hg is expected to increase in the Arctic, raising concern for continued population declines in high-latitude species that are far from sources of environmental contaminants.

  10. Rapidly increasing methyl mercury in endangered ivory gull (Pagophila eburnea) feathers over a 130 year record

    PubMed Central

    Bond, Alexander L.; Hobson, Keith A.; Branfireun, Brian A.

    2015-01-01

    Mercury (Hg) is increasing in marine food webs, especially at high latitudes. The bioaccumulation and biomagnification of methyl mercury (MeHg) has serious effects on wildlife, and is most evident in apex predators. The MeHg body burden in birds is the balance of ingestion and excretion, and MeHg in feathers is an effective indicator of overall MeHg burden. Ivory gulls (Pagophila eburnea), which consume ice-associated prey and scavenge marine mammal carcasses, have the highest egg Hg concentrations of any Arctic bird, and the species has declined by more than 80% since the 1980s in Canada. We used feathers from museum specimens from the Canadian Arctic and western Greenland to assess whether exposure to MeHg by ivory gulls increased from 1877 to 2007. Based on constant feather stable-isotope (δ13C, δ15N) values, there was no significant change in ivory gulls' diet over this period, but feather MeHg concentrations increased 45× (from 0.09 to 4.11 µg g−1 in adults). This dramatic change in the absence of a dietary shift is clear evidence of the impact of anthropogenic Hg on this high-latitude threatened species. Bioavailable Hg is expected to increase in the Arctic, raising concern for continued population declines in high-latitude species that are far from sources of environmental contaminants. PMID:25788594

  11. Living on the edge of a shrinking habitat: the ivory gull, Pagophila eburnea, an endangered sea-ice specialist.

    PubMed

    Gilg, Olivier; Istomina, Larysa; Heygster, Georg; Strøm, Hallvard; Gavrilo, Maria V; Mallory, Mark L; Gilchrist, Grant; Aebischer, Adrian; Sabard, Brigitte; Huntemann, Marcus; Mosbech, Anders; Yannic, Glenn

    2016-11-01

    The ongoing decline of sea ice threatens many Arctic taxa, including the ivory gull. Understanding how ice-edges and ice concentrations influence the distribution of the endangered ivory gulls is a prerequisite to the implementation of adequate conservation strategies. From 2007 to 2013, we used satellite transmitters to monitor the movements of 104 ivory gulls originating from Canada, Greenland, Svalbard-Norway and Russia. Although half of the positions were within 41 km of the ice-edge (75% within 100 km), approximately 80% were on relatively highly concentrated sea ice. Ivory gulls used more concentrated sea ice in summer, when close to their high-Arctic breeding ground, than in winter. The best model to explain the distance of the birds from the ice-edge included the ice concentration within approximately 10 km, the month and the distance to the colony. Given the strong links between ivory gull, ice-edge and ice concentration, its conservation status is unlikely to improve in the current context of sea-ice decline which, in turn, will allow anthropogenic activities to develop in regions that are particularly important for the species.

  12. Breeding biology and relation of pollutants to black skimmers and gull-billed terns in South Carolina

    USGS Publications Warehouse

    Blus, Lawrence J.; Stafford, Charles J.

    1980-01-01

    The breeding biology and relation of pollutants to black skimmers (Ryn chops niger) and gull-billed terns (Gelochelidon nilotica) were investigated in South Carolina from 1969 through 1975. With few exceptions, the two species nested together in colonies located on barrier islands. We located 10 colonies, 7 of which were on the Cape Romain National Wildlife Refuge (Cape Romain); references were located that described nesting on seven other islands in South Carolina that no longer support colonies. Gull-billed terns nested from early May through July; the skimmers started later (late May) but also continued later (early September). Both species nested in areas subject to tidal flooding, and the two species persisted in nesting in several colonies despite intense predation by rats and gulls. Estimated reproductive success varied greatly from year to year and colony to colony; success in most colonies seemed low, particularly for the gull-billed tern. Residues of organochlorine pollutants in several eggs seemed of sufficient magnitude to induce adverse effects on reproductivity and eggshell thickness: however, the overall effect of organochlorines appeared negligible. Maximum numbers of nests located in a single year were 790 for the skimmer and 340 for the gull-billed tern: the total breeding population in South Carolina is unknown. Although nesting islands at Cape Romain and Deveaux Bank are sanctuaries for nesting birds, both species will continue to lose nesting habitat as additional sea islands are developed and inhabited by man.

  13. Salmonella enterica resistant to antimicrobials in wastewater effluents and black-headed gulls in the Czech Republic, 2012.

    PubMed

    Masarikova, Martina; Manga, Ivan; Cizek, Alois; Dolejska, Monika; Oravcova, Veronika; Myskova, Petra; Karpiskova, Renata; Literak, Ivan

    2016-01-15

    We investigated the presence and epidemiological relatedness of Salmonella isolates from a wastewater treatment plant (WWTP) in Brno, Czech Republic and from nestlings of black-headed gulls (Chroicocephalus ridibundus) at the Nove Mlyny waterworks, situated 35 km downstream from the WWTP. During 2012, we collected 37 wastewater samples and 284 gull cloacal swabs. From wastewater samples, we obtained 89 Salmonella isolates belonging to 19 serotypes. At least one resistant strain was contained in 89% of those samples. Ten different serotypes of Salmonella were detected in 38 young gulls, among which 14 (37%) were resistant to antimicrobials. Wastewater isolates were mostly resistant to sulphonamides and tetracycline, gull isolates to tetracycline and ampicillin. We detected the occurrence of blaTEM-1,tet(A), tet(B), tet(G), sul1, sul2, sul3, floR and strA resistance genes. For the first time, we identified a class 1 integron with the dfrA12-orfF-aadA2 gene cassette in S. Infantis. Using pulsed-field gel electrophoresis, we confirmed the presence of identical clusters of S. Agona, S. Enteritidis PT8, S. Infantis and S. Senftenberg in wastewater and black-headed gulls, thus indicating the possibility of resistant Salmonella isolates spreading over long distances in the environment.

  14. Egg oiling to reduce hatch-year ring-billed gull numbers on Chicago's beaches during swim season and water quality test results.

    PubMed

    Engeman, Richard M; Hartmann, John W; Beckerman, Scott F; Seamans, Thomas W; Abu-Absi, Sarah

    2012-06-01

    A burgeoning ring-billed gull population along Chicago's Lake Michigan beaches contributes to degraded water quality through fecal contamination. Egg oiling was conducted at Chicago's gull colonies to reduce production and the influx of hatch-year (HY) gulls using Chicago's beaches, with a second, long-term objective of eventually reducing adult gull numbers through attrition. We also investigated swim season water quality trends through the course of this work. From 2007 to 2009, 52, 80, and 81%, of nests at the two primary nest colonies had their eggs rendered inviable by corn oil application. Counts of HY and after hatch-year (AHY) gulls were analyzed during treatment years for 10 beaches. Water quality data were available from the Chicago Park District during our three treatment years and the prior year (baseline) for 19 beaches. HY counts declined at all 10 surveyed beaches from the initial year (52% nests with oiled eggs) to subsequent years with ~80% of nests oiled. Overall, HY gulls numbers on beaches decreased 86% from 2007 to 2009. Decreases in beach usage by AHY gulls were not detected. Compared to pretreatment, the number of beaches with improved water quality test rates increased each year through the course of the study. The frequency of water quality tests showing bacterial exceedances compared to 2006 declined at 18 of 19 beaches by 2009. Egg oiling resulted in fewer HY gulls using Chicago's beaches and was likely a beneficial factor for reduced frequencies of swim advisories and swim bans.

  15. Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, April 1994 to March 1995

    USGS Publications Warehouse

    Wang, Bronwen; Rockwell, G.L.; Blodgett, J.C.

    1995-01-01

    Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, were collected from April 1994 to March 1995. Water samples were analyzed for major ions and trace elements, nutrients, methylene blue active substances, and oil and grease. Field measurements were made for discharge, specific conductance, pH, water temperature, barometric pressure, dissolved oxygen, and alkalinity. Additional data collected include vertical water profiles of specific conductance, pH, water temperature, and dissolved oxygen collected at 3.3-foot intervals for Gull and Silver Lakes; chlorophyll-a and -b concentrations and Secchi depth for Gull and Silver Lakes; sediment interstitial- water nutrient concentrations in cores from Gull Lake; and lake surface and volume of Gull and Silver Lakes.

  16. Molecular epidemiology of Salmonella spp. isolates from gulls, fish-meal factories, feed factories, animals and humans in Norway based on pulsed-field gel electrophoresis.

    PubMed Central

    Nesse, L. L.; Refsum, T.; Heir, E.; Nordby, K.; Vardund, T.; Holstad, G.

    2005-01-01

    The molecular epidemiology of 98 isolates of Salmonella serovar Agona (n = 27), S. Montevideo (n = 42) and S. Senftenberg (n = 29) from wild-living gulls, fish-meal factories, feed factories, humans and domestic animals was investigated using pulsed-field gel electrophoresis (PFGE) and computerized numerical analysis. Two of the S. Agona profiles were identified both in gulls and in two of the factories. In addition, one of these profiles was detected in two infected poultry farms. Two of the S. Montevideo profiles were also identified both in gulls and in two of the factories, and one of these profiles was observed in a human isolate. Four factories shared an identical S. Senftenberg profile. The S. Senftenberg profile found in gulls was not identified in any other source investigated. The presence of isolates with identical PFGE profiles indicates potential epidemiological links between different factories, as well as between gulls and factories. PMID:15724711

  17. Genetic Markers for Rapid PCR-Based Identification of Gull, Canada Goose, Duck, and Chicken Fecal Contamination in Water

    PubMed Central

    Green, Hyatt C.; Dick, Linda K.; Gilpin, Brent; Samadpour, Mansour

    2012-01-01

    Avian feces contaminate waterways but contribute fewer human pathogens than human sources. Rapid identification and quantification of avian contamination would therefore be useful to prevent overestimation of human health risk. We used subtractive hybridization of PCR-amplified gull fecal 16S RNA genes to identify avian-specific fecal rRNA gene sequences. The subtracters were rRNA genes amplified from human, dog, cat, cow, and pig feces. Recovered sequences were related to Enterobacteriaceae (47%), Helicobacter (26%), Catellicoccus (11%), Fusobacterium (11%), and Campylobacter (5%). Three PCR assays, designated GFB, GFC, and GFD, were based on recovered sequence fragments. Quantitative PCR assays for GFC and GFD were developed using SYBR green. GFC detected down to 0.1 mg gull feces/100 ml (corresponding to 2 gull enterococci most probable number [MPN]/100 ml). GFD detected down to 0.1 mg chicken feces/100 ml (corresponding to 13 Escherichia coli MPN/100 ml). GFB and GFC were 97% and 94% specific to gulls, respectively. GFC cross-reacted with 35% of sheep samples but occurred at about 100,000 times lower concentrations in sheep. GFD was 100% avian specific and occurred in gulls, geese, chickens, and ducks. In the United States, Canada, and New Zealand, the three markers differed in their geographic distributions but were found across the range tested. These assays detected four important bird groups contributing to fecal contamination of waterways: gulls, geese, ducks, and chickens. Marker distributions across North America and in New Zealand suggest that they will have broad applicability in other parts of the world as well. PMID:22081573

  18. Circumpolar contamination in eggs of the high-Arctic ivory gull Pagophila eburnea.

    PubMed

    Lucia, Magali; Verboven, Nanette; Strøm, Hallvard; Miljeteig, Cecilie; Gavrilo, Maria V; Braune, Birgit M; Boertmann, David; Gabrielsen, Geir W

    2015-07-01

    The ivory gull Pagophila eburnea is a high-Arctic species threatened by climate change and contaminants. The objective of the present study was to assess spatial variation of contaminant levels (organochlorines [OCs], brominated flame retardants [BFRs], perfluorinated alkyl substances [PFASs], and mercury [Hg]) in ivory gulls breeding in different areas across the Arctic region as a baseline for potential future changes associated with climate change. Contaminants were already determined in eggs from Canada (Seymour Island; except PFASs), Svalbard in Norway (Svenskøya), and 3 sites in Russia (Nagurskoe, Cape Klyuv, and Domashny). New data from Greenland allowed the investigation of a possible longitudinal gradient of contamination. The most quantitatively abundant OCs were p,p'-dichlorodiphenyldichloroethylene (DDE) and polychlorobiphenyls. Mercury concentrations were higher in Canada compared with other colonies. Eggs from Nagurskoe often were characterized by higher OC and BFR concentrations. Concentrations gradually decreased in colonies situated east of Nagurskoe. In contrast, PFAS concentrations, especially perfluorooctanoate and perfluorononanoate, were higher in Greenland. Some of the contaminants, especially Hg and p,p'-DDE, exceeded published thresholds known to disrupt the reproductive success of avian species. Overall, the levels of OCs, BFRs, and PFASs did not suggest direct lethal exposure to these compounds, but their potential synergetic/additive sublethal effects warrant monitoring.

  19. Geographical distribution of organochlorine contaminants and reproductive parameters in Herring Gulls on Lake Superior in 1983.

    PubMed

    Chip Weseloh, D V; Ewins, P J; Struger, J; Mineau, P; Norstrom, R J

    1994-02-01

    As part of the Great Lakes International Surveillance Plan, 1978-83, egg contaminant levels and reproductive output were determined for Herring Gull colonies on Lake Superior in 1983. Since 1974, the Herring Gull has been widely used in the Great Lakes as a spatial and temporal monitor of organochlorine (OC) contaminant levels and associated biological effects. Most eggs contained a wide range of OCs, the main compounds being DDE, polychlorinated biphenyls (PCBs), dieldrin, heptachlor epoxide, oxychlordane, hexachlorobenzene and mirex. Levels of an additional ten OCs and five polychlorinated dibenzo-p-dioxin (PCDD) congeners were also determined for some sites. Overall, levels varied significantly among colonies, but there was no obvious relationship to spatial distribution of contaminants in sediments or fish species. OC levels in eggs had declined by up to 84% since 1974. Eggshells were only 8% thinner than before the introduction of DDT, and shell thinning was not a cause of breeding failure. Average reproductive output varied from 0.15 to 1.57 young per apparently occupied nest in 1983: at 56% of colonies the value was below that thought necessary to maintain stable populations. The main causes of failure were egg disappearence and cannibalism of chicks. Despite this, the population appeared to have been increasing at about 4% per annum. Reduced availability of forage fish during the early 1980s was the most likely reason for the poor reproductive output in 1983.

  20. Development and application of a quantitative PCR assay targeting Catellicoccus marimammalium for assessing gull-associated fecal contamination at Lake Erie beaches.

    PubMed

    Lee, Cheonghoon; Marion, Jason W; Lee, Jiyoung

    2013-06-01

    Gulls represent one of the major fecal contamination sources responsible for the degradation of water quality at Lake Erie beaches. For assessing gull-associated fecal contamination, a real-time quantitative PCR assay (qPCR) targeting 16S rRNA gene sequences from Catellicoccus marimammalium, which are abundant in gull feces, was developed and evaluated by comparing assay results with beach survey data that included gull counting, and quantifying densities of Escherichia coli and human-associated fecal markers at two Lake Erie beaches. In evaluating the specificity and sensitivity of the qPCR assay with animal and wastewater samples, C. marimammalium was detected in most gull fecal samples (80.7%), some chicken fecal samples (24.1%), but was not readily detected from other fecal samples of animals and humans, and wastewater. Among 66 Lake Erie water samples collected in 2010, C. marimammalium was frequently detected from Villa Angela (36.4%) and Headlands beaches (57.6%). C. marimammalium densities were not associated with E. coli densities or sanitary survey data. E. coli counts were likely driven by other sources, such as human, rather than gulls at the study sites. The presumption that human contamination influenced E. coli counts was supported by more frequent detection of the human-specific Bacteroides gyrB marker (gyrB) at Villa Angela (33.3%) than Headlands (6.1%). Since E. coli may not be an effective indicator for assessing gull-related fecal contamination at these beaches, where contamination sources are mixed, our novel qPCR assay can be useful for understanding fecal source contributions from gulls not explained by gull abundance or E. coli densities.

  1. Molecular characterization and phylogenetics of a reassortant H13N8 influenza virus isolated from gulls in Mongolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A double reassortant H13N8 influenza A virus was isolated from gulls in Mongolia. The basic virological characteristics were studied. Complete genome sequence analysis indicated the complicated evolutionary history. The PA gene belongs to classical Avian-like lineage and more likely originated fro...

  2. Storage capacity, detention time, and selected sediment deposition characteristics for Gull and Silver Lakes, Mono County, California

    USGS Publications Warehouse

    Blodgett, J.C.

    1996-01-01

    Bathymetric surveys made in September 1994 indicate the maximum storage capacity of Gull and Silver Lakes, California, is about 2,400 and 3,000 acre-feet, respectively. During March through October 1994, the lake level dropped 0.7 feet at both Gull Lake and Silver Lake. The associated change in storage was 60 acre-feet at Gull Lake and 80 acre-feet at Silver Lake. The flow detention time for average annual flow conditions at Gull Lake is about 2.5 years and for Silver Lake, the average detention time is about 19 days. Sediment deposition at the inlet to Silver Lake has been monitored since 1951 using aerial photography. During 1963 through 1994, the area of sediment deposition increased from 0.32 to about 2.4 acres. Analyses of these data indicate that the rate of deposition was lower during 1951-72 than the rate during 1973-94. Sediment deposition at the lake inlet is a continuing phenomenon.

  3. Comparison of Extended-Spectrum β-Lactamase (ESBL) CTX-M Genotypes in Franklin Gulls from Canada and Chile

    PubMed Central

    Waldenström, Jonas; Svensson, Lovisa; Drobni, Mirva; Olsen, Björn

    2015-01-01

    Migratory birds have been suggested to contribute to long-distance dispersal of antimicrobial resistant bacteria, but tests of this hypothesis are lacking. In this study we determined resistance profiles and genotypes of ESBL-producing bacteria in randomly selected Escherichia coli from Franklin´s gulls (Leucophaeus pipixcan) at breeding sites in Canada and compared with similar data from the gulls' wintering grounds in Chile. Resistant E. coli phenotypes were common, most notably to ampicillin (30.1%) and cefadroxil (15.1%). Furthermore, 17.0% of the gulls in Canada carried ESBL producing bacteria, which is higher than reported from human datasets from the same country. However, compared to gulls sampled in Chile (30.1%) the prevalence of ESBL was much lower. The dominant ESBL variants in Canada were blaCTX-M-14 and blaCTX-M-15 and differed in proportions to the data from Chile. We hypothesize that the observed differences in ESBL variants are more likely linked to recent exposure to bacteria from anthropogenic sources, suggesting high local dissemination of resistant bacteria both at breeding and non-breeding times rather than a significant trans-hemispheric exchange through migrating birds. PMID:26496629

  4. Comparison of Extended-Spectrum β-Lactamase (ESBL) CTX-M Genotypes in Franklin Gulls from Canada and Chile.

    PubMed

    Bonnedahl, Jonas; Stedt, Johan; Waldenström, Jonas; Svensson, Lovisa; Drobni, Mirva; Olsen, Björn

    2015-01-01

    Migratory birds have been suggested to contribute to long-distance dispersal of antimicrobial resistant bacteria, but tests of this hypothesis are lacking. In this study we determined resistance profiles and genotypes of ESBL-producing bacteria in randomly selected Escherichia coli from Franklin´s gulls (Leucophaeus pipixcan) at breeding sites in Canada and compared with similar data from the gulls' wintering grounds in Chile. Resistant E. coli phenotypes were common, most notably to ampicillin (30.1%) and cefadroxil (15.1%). Furthermore, 17.0% of the gulls in Canada carried ESBL producing bacteria, which is higher than reported from human datasets from the same country. However, compared to gulls sampled in Chile (30.1%) the prevalence of ESBL was much lower. The dominant ESBL variants in Canada were blaCTX-M-14 and blaCTX-M-15 and differed in proportions to the data from Chile. We hypothesize that the observed differences in ESBL variants are more likely linked to recent exposure to bacteria from anthropogenic sources, suggesting high local dissemination of resistant bacteria both at breeding and non-breeding times rather than a significant trans-hemispheric exchange through migrating birds.

  5. Cultural Resources Investigation of the Reservoir Shorelines: Gull Lake, Leech Lake, Pine River and Lake Pokegama. Volume 2. Site Location Data.

    DTIC Science & Technology

    1979-06-01

    affiliation Malmo (Middle Woodland ); Blackduck 4. Location: Sec. 4 Twp. 135N R. 29W Verbal description E NWk north end Upper Gull; just east of bridge over...affiliation Woodland 4. Location: Sec. 25 Twp. 134N R. 30W Verbal description NWk SEk on the southeast arm of the southwest part of Wilson Bay, Gull...mound, village, etc.) mound? burial? 2. Map reference USGS Gull Lake 3. Cultural affiliation Woodland and Historic 4. Location: Sec. 21 Tp. 135N R. 29W

  6. High Prevalence of SXT/R391-Related Integrative and Conjugative Elements Carrying blaCMY-2 in Proteus mirabilis Isolates from Gulls in the South of France.

    PubMed

    Aberkane, Salim; Compain, Fabrice; Decré, Dominique; Dupont, Chloé; Laurens, Chrislène; Vittecoq, Marion; Pantel, Alix; Solassol, Jérôme; Carrière, Christian; Renaud, François; Brieu, Nathalie; Lavigne, Jean-Philippe; Bouzinbi, Nicolas; Ouédraogo, Abdoul-Salam; Jean-Pierre, Hélène; Godreuil, Sylvain

    2016-02-01

    The genetic structures involved in the dissemination of blaCMY-2 carried by Proteus mirabilis isolates recovered from different gull species in the South of France were characterized and compared to clinical isolates. blaCMY-2 was identified in P. mirabilis isolates from 27/93 yellow-legged gulls and from 37/65 slender-billed gulls. It was carried by a conjugative SXT/R391-like integrative and conjugative element (ICE) in all avian strains and in 3/7 human strains. Two clinical isolates had the same genetic background as six avian isolates.

  7. High Prevalence of SXT/R391-Related Integrative and Conjugative Elements Carrying blaCMY-2 in Proteus mirabilis Isolates from Gulls in the South of France

    PubMed Central

    Compain, Fabrice; Decré, Dominique; Dupont, Chloé; Laurens, Chrislène; Vittecoq, Marion; Pantel, Alix; Solassol, Jérôme; Carrière, Christian; Renaud, François; Brieu, Nathalie; Bouzinbi, Nicolas; Ouédraogo, Abdoul-Salam; Jean-Pierre, Hélène; Godreuil, Sylvain

    2015-01-01

    The genetic structures involved in the dissemination of blaCMY-2 carried by Proteus mirabilis isolates recovered from different gull species in the South of France were characterized and compared to clinical isolates. blaCMY-2 was identified in P. mirabilis isolates from 27/93 yellow-legged gulls and from 37/65 slender-billed gulls. It was carried by a conjugative SXT/R391-like integrative and conjugative element (ICE) in all avian strains and in 3/7 human strains. Two clinical isolates had the same genetic background as six avian isolates. PMID:26643344

  8. Novel flame retardants in urban-feeding ring-billed gulls from the St. Lawrence River, Canada.

    PubMed

    Gentes, Marie-Line; Letcher, Robert J; Caron-Beaudoin, Elyse; Verreault, Jonathan

    2012-09-04

    This study investigated the occurrence of a comprehensive suite of polybrominated diphenyl ethers (PBDEs) and current-use flame retardants (FRs) in ring-billed gulls breeding in a highly industrialized section of the St. Lawrence River, downstream from Montreal (QC, Canada). Despite major point-sources and diffuse contamination by FRs, nearly no FR data have been reported in birds from this area. Bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (BEHTBP) was detected in 89% of ring-billed gull livers (mean: 2.16 ng/g ww; max: 17.6 ng/g ww). To our knowledge, this is the highest detection frequency and highest concentrations reported thus far in any avian species or populations. Dechlorane Plus (DP) isomers were also particularly abundant (anti-DP detected in 100% and syn-DP in 93% of livers). Other detected FR compounds (3-14% detection) included 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) and β-1,2-dibromo-4-(1.2-dibromoethyl)-cyclohexane (β-TBECH). Mean BDE-209 (57.2 ± 12.2 ng/g ww) in ring-billed gull livers was unexpectedly high for this midtrophic gull species, exceeding levels reported in several apex raptors such as peregrine falcons. BDE-209's relative contribution to ∑PBDEs was on average 25% (exceeding BDE-47 and BDE-99) and contrasted with profiles typically reported for fish-eating gull species. The present study highlighted preoccupying gaps in upcoming FR regulations and stressed the need for further investigation of the sources of FR exposure in highly urbanized areas.

  9. High prevalence of Salmonella and IMP-4-producing Enterobacteriaceae in the silver gull on Five Islands, Australia

    PubMed Central

    Dolejska, Monika; Masarikova, Martina; Dobiasova, Hana; Jamborova, Ivana; Karpiskova, Renata; Havlicek, Martin; Carlile, Nicholas; Priddel, David; Cizek, Alois; Literak, Ivan

    2016-01-01

    Objectives The objective of this study was to investigate the silver gull as an indicator of environmental contamination by salmonellae and carbapenemase-producing Enterobacteriaceae (CPE) in south-east Australia. Methods A total of 504 cloacal samples were collected from gull chicks at three nesting colonies in New South Wales, Australia [White Bay (n = 144), Five Islands (n = 200) and Montague Island (n = 160)] and were examined for salmonellae and CPE. Isolates were tested for carbapenemase genes and susceptibility to 14 antibiotics. Clonality was determined by PFGE and MLST. Genetic context and conjugative transfer of the carbapenemase gene were determined. Results A total of 120 CPE of 10 species, mainly Escherichia coli (n = 85), carrying the gene blaIMP-4, blaIMP-38 or blaIMP-26 were obtained from 80 (40%) gulls from Five Islands. Thirty percent of birds from this colony were colonized by salmonellae. Most isolates contained the gene within a class 1 integron showing a blaIMP-4-qacG-aacA4-catB3 array. The blaIMP gene was carried by conjugative plasmids of variable sizes (80–400 kb) and diverse replicons, including HI2-N (n = 30), HI2 (11), A/C (17), A/C-Y (2), L/M (5), I1 (1) and non-typeable (6). Despite the overall high genetic variability, common clones and plasmid types were shared by different birds and bacterial isolates, respectively. Conclusions Our data demonstrate a large-scale transmission of carbapenemase-producing bacteria into wildlife, likely as a result of the feeding habits of the birds at a local waste depot. The isolates from gulls showed significant similarities with clinical isolates from Australia, suggesting the human origin of the isolates. The sources of CPE for gulls on Five Islands should be explored and proper measures applied to stop the transmission into the environment. PMID:26472769

  10. Effects of laughing gull and shorebird predation on the intertidal fauna at Cape May, New Jersey

    NASA Astrophysics Data System (ADS)

    Botton, M. L.

    1984-02-01

    The intertidal flats of the Cape May, New Jersey shore of Delaware Bay are populated by large numbers of laughing gulls and migrating shorebirds during the spring and early summer. Exclusion of birds from a shallow slough and a sand bar had only minor effects on the infaunal benthic invertebrate assemblage at either site. The Cape May beaches provide a rich source of food in the form of horseshoe crab ( Limulus polyphemus) eggs; foraging on this item may be more profitable than probing the sediment for infauna. Gemma gemma, a small, thick-shelled bivalve, composed over 98% of the benthic infauna at both sites in 1980, and this species may be resistant to predation by certain shorebirds, as suggested by Schneider (1978).

  11. Landscape changes and colony site dynamics: How gull-billed terns cope at the sea's edge

    USGS Publications Warehouse

    Erwin, R.M.; Williams, B.; Watts, B.; Truitt, B.; Stotts, D.; Eyler, B.

    1996-01-01

    Gull-billed Terns have declined dramatically in coastal Virginia over the past 20 years, with apparently low reproductive success. They nest, usually in mixed-species colonies, in two discrete habitat types: large, sandy barrier islands or shell/sandbars on the edges of marsh islands in the lagoon systems. The smaller shell/sandbars seem to provide more consistent nestling habitat and predation pressures than do barrier islands among years. We hypothesize that colony site turnover (between years) should be higher in the more uncertain barrier island habitats than among the shell/sandbar colonies. Our results do not corroborate the prediction. We postulate that social (and other) factors may explain these differences.

  12. Aspects of hatching success and chick survival in Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Eyler, T.B.; Erwin, R.M.; Stotts, D.B.; Hatfield, J.S.

    1999-01-01

    Because of a long-term population decline in Gull-billed Terns (Sterna nilotica) nesting along the coast of Virginia, we began a three year study in 1994 to monitor hatching success and survival of Gull-billed Tern chicks at several Virginia colony sites. Colonies were located on either small, storm-deposited shellpiles along marsh fringes or large, sandshell overwash fans of barrier islands. Nests were monitored one to three times a week for hatching success, and enclosures were installed around selected nests to monitor chick survival from hatching to about two weeks of age. Hatching success was lower in marsh colonies than island colonies, and was lower in 1995 than in 1994 and 1996, primarily because of flooding. The average brood size of nests where at least one chick hatched was 1.99 chicks. Survival rates of chicks to 14 days depended on hatch order and year but not brood size (one vs. two or more) or time of season. A-chicks had higher survival rates than B-chicks and third-hatched C-chicks (0.661 compared to 0.442 and 0.357, respectively). The year effect was significant only for A-chicks, with lower survival in 1994 (0.50) than in 1995 (0.765) or 1996 (0.758). Overall, productivity was low (0.53 chick per nest) compared to estimates for colonies in Denmark, and was attributable to nest flooding by spring and storm-driven high tides and chick predation, presumably mostly by Great Horned Owls (Bubo virginianus).

  13. Trace Element Concentrations in Relation to the Trophic Behaviour of Endangered Ivory Gulls (Pagophila eburnea) During Their Stay at a Breeding Site in Svalbard.

    PubMed

    Lucia, Magali; Strøm, Hallvard; Bustamante, Paco; Gabrielsen, Geir W

    2016-11-01

    The ivory gull is a high-Arctic species considered endangered in most parts of its breeding range. Ivory gulls must cope with both the reduction of sea ice cover triggered by climate change and increasing contaminant loads due to changes in global contaminant pathways. The objective of this study was to assess the concentration of 14 essential and nonessential trace elements at four colonies of ivory gulls breeding on Barentsøya, Svalbard, and the relationship between contaminant exposure and the diet of individuals. Contaminants and stable isotopes (δ(15)N, δ(13)C) were determined in blood (red blood cells and whole blood), and feathers of ivory gulls collected over several years. The most quantitatively abundant nonessential trace element found in the ivory gull was mercury (Hg). Selenium (Se) was present in substantial surplus compared with Hg, which would imply relative protection against Hg toxic effects but raises concern about Se potential toxicity. Moreover, other elements were detected, such as silver, arsenic, cadmium, and lead, which would warrant monitoring because of the potential additive/synergetic effects of these compounds. This study demonstrated individual differences in trophic behaviour that triggered discrepancies in Hg concentrations, highlighting the potential biomagnifying ability of this metal in the ivory gull's food web. Results highlighted the mixing of birds coming from different geographical areas on Barentsøya.

  14. Conservation genetics of high-arctic Gull species at risk: I. Diversity in the mtDNA control region of circumpolar populations of the Endangered Ivory Gull (Pagophila eburnea).

    PubMed

    Royston, Stephanie R; Carr, Steven M

    2016-11-01

    The high-arctic Ivory Gull (Pagophila eburnea) has recently undergone a sharp decline in numbers, and in Canada it is listed as "Endangered" under the Species-At-Risk Act. To test for circumpolar genetic distinctiveness, we examined 264 bp of the mtDNA Control Region Domain I from 127 museum specimens collected during the breeding season from northern Canada, Greenland, and Norway, and during the non-breeding season from adjacent overwintering grounds in Canada, Greenland, and a disjunct area in Alaska adjacent to the Bering Sea. Partition of genetic variance according to various phylogeographic and breeding ground models indicates no strong population structure, except that Alaska birds are consistently differentiated from other locations, and there are significant temporal shifts in haplotype frequencies. The evidence suggests that Ivory Gulls in Canada, Greenland, and Norway are a single genetic entity, in contrast to Alaska birds, which may represent a distinctive Siberian population.

  15. At-sea behavior varies with lunar phase in a nocturnal pelagic seabird, the swallow-tailed gull.

    PubMed

    Cruz, Sebastian M; Hooten, Mevin; Huyvaert, Kathryn P; Proaño, Carolina B; Anderson, David J; Afanasyev, Vsevolod; Wikelski, Martin

    2013-01-01

    Strong and predictable environmental variability can reward flexible behaviors among animals. We used long-term records of activity data that cover several lunar cycles to investigate whether behavior at-sea of swallow-tailed gulls Creagrus furcatus, a nocturnal pelagic seabird, varied with lunar phase in the Galápagos Islands. A Bayesian hierarchical model showed that nighttime at-sea activity of 37 breeding swallow-tailed gulls was clearly associated with changes in moon phase. Proportion of nighttime spent on water was highest during darker periods of the lunar cycle, coinciding with the cycle of the diel vertical migration (DVM) that brings prey to the sea surface at night. Our data show that at-sea behavior of a tropical seabird can vary with environmental changes, including lunar phase.

  16. At–Sea Behavior Varies with Lunar Phase in a Nocturnal Pelagic Seabird, the Swallow-Tailed Gull

    PubMed Central

    Cruz, Sebastian M.; Hooten, Mevin; Huyvaert, Kathryn P.; Proaño, Carolina B.; Anderson, David J.; Afanasyev, Vsevolod; Wikelski, Martin

    2013-01-01

    Strong and predictable environmental variability can reward flexible behaviors among animals. We used long-term records of activity data that cover several lunar cycles to investigate whether behavior at-sea of swallow-tailed gulls Creagrus furcatus, a nocturnal pelagic seabird, varied with lunar phase in the Galápagos Islands. A Bayesian hierarchical model showed that nighttime at-sea activity of 37 breeding swallow-tailed gulls was clearly associated with changes in moon phase. Proportion of nighttime spent on water was highest during darker periods of the lunar cycle, coinciding with the cycle of the diel vertical migration (DVM) that brings prey to the sea surface at night. Our data show that at-sea behavior of a tropical seabird can vary with environmental changes, including lunar phase. PMID:23468889

  17. At-sea behavior varies with lunar phase in a nocturnal pelagic seabird, the swallow-tailed gull

    USGS Publications Warehouse

    Cruz, Sebastian M.; Hooten, Mevin; Huyvaert, Kathryn P.; Proaño, Carolina B.; Anderson, David J.; Afanasyev, Vsevolod; Wikelski, Martin

    2013-01-01

    Strong and predictable environmental variability can reward flexible behaviors among animals. We used long-term records of activity data that cover several lunar cycles to investigate whether behavior at-sea of swallow-tailed gulls Creagrus furcatus, a nocturnal pelagic seabird, varied with lunar phase in the Galápagos Islands. A Bayesian hierarchical model showed that nighttime at-sea activity of 37 breeding swallow-tailed gulls was clearly associated with changes in moon phase. Proportion of nighttime spent on water was highest during darker periods of the lunar cycle, coinciding with the cycle of the diel vertical migration (DVM) that brings prey to the sea surface at night. Our data show that at-sea behavior of a tropical seabird can vary with environmental changes, including lunar phase.

  18. The genome of an influenza virus from a pilot whale: relation to influenza viruses of gulls and marine mammals.

    PubMed

    Groth, Marco; Lange, Jeannette; Kanrai, Pumaree; Pleschka, Stephan; Scholtissek, Christoph; Krumbholz, Andi; Platzer, Matthias; Sauerbrei, Andreas; Zell, Roland

    2014-06-01

    Influenza virus A/whale/Maine/328B/1984 (H13N2) was isolated from a diseased pilot whale. Since only a partial sequence was available, its complete genome was sequenced and compared to the sequences of subtype H13 influenza viruses from shorebirds and various influenza viruses of marine mammals. The data reveal a rare genotype constellation with all gene segments derived of an influenza virus adapted to gulls, terns and waders. In contrast, the phylogenetic trees indicate that the majority of influenza viruses isolated from marine mammals derived from influenza viruses adapted to geese and ducks. We conclude that A/whale/Maine/328B/1984 is the first record of an infection of a marine mammal from a gull-origin influenza virus.

  19. Multi-laboratory evaluations of the performance of Catellicoccus marimammalium PCR assays developed to target gull fecal sources

    USGS Publications Warehouse

    Sinigalliano, Christopher D.; Ervin, Jared S.; Van De Werfhorst, Laurie C.; Badgley, Brian D.; Ballestée, Elisenda; Bartkowiaka, Jakob; Boehm, Alexandria B.; Byappanahalli, Muruleedhara N.; Goodwin, Kelly D.; Gourmelon, Michèle; Griffith, John; Holden, Patricia A.; Jay, Jenny; Layton, Blythe; Lee, Cheonghoon; Lee, Jiyoung; Meijer, Wim G.; Noble, Rachel; Raith, Meredith; Ryu, Hodon; Sadowsky, Michael J.; Schriewer, Alexander; Wang, Dan; Wanless, David; Whitman, Richard; Wuertz, Stefan; Santo Domingo, Jorge W.

    2013-01-01

    Here we report results from a multi-laboratory (n = 11) evaluation of four different PCR methods targeting the 16S rRNA gene of Catellicoccus marimammalium originally developed to detect gull fecal contamination in coastal environments. The methods included a conventional end-point PCR method, a SYBR® Green qPCR method, and two TaqMan® qPCR methods. Different techniques for data normalization and analysis were tested. Data analysis methods had a pronounced impact on assay sensitivity and specificity calculations. Across-laboratory standardization of metrics including the lower limit of quantification (LLOQ), target detected but not quantifiable (DNQ), and target not detected (ND) significantly improved results compared to results submitted by individual laboratories prior to definition standardization. The unit of measure used for data normalization also had a pronounced effect on measured assay performance. Data normalization to DNA mass improved quantitative method performance as compared to enterococcus normalization. The MST methods tested here were originally designed for gulls but were found in this study to also detect feces from other birds, particularly feces composited from pigeons. Sequencing efforts showed that some pigeon feces from California contained sequences similar to C. marimammalium found in gull feces. These data suggest that the prevalence, geographic scope, and ecology of C. marimammalium in host birds other than gulls require further investigation. This study represents an important first step in the multi-laboratory assessment of these methods and highlights the need to broaden and standardize additional evaluations, including environmentally relevant target concentrations in ambient waters from diverse geographic regions.

  20. Fine-scale flight strategies of gulls in urban airflows indicate risk and reward in city living.

    PubMed

    Shepard, Emily L C; Williamson, Cara; Windsor, Shane P

    2016-09-26

    Birds modulate their flight paths in relation to regional and global airflows in order to reduce their travel costs. Birds should also respond to fine-scale airflows, although the incidence and value of this remains largely unknown. We resolved the three-dimensional trajectories of gulls flying along a built-up coastline, and used computational fluid dynamic models to examine how gulls reacted to airflows around buildings. Birds systematically altered their flight trajectories with wind conditions to exploit updraughts over features as small as a row of low-rise buildings. This provides the first evidence that human activities can change patterns of space-use in flying birds by altering the profitability of the airscape. At finer scales still, gulls varied their position to select a narrow range of updraught values, rather than exploiting the strongest updraughts available, and their precise positions were consistent with a strategy to increase their velocity control in gusty conditions. Ultimately, strategies such as these could help unmanned aerial vehicles negotiate complex airflows. Overall, airflows around fine-scale features have profound implications for flight control and energy use, and consideration of this could lead to a paradigm-shift in the way ecologists view the urban environment.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'.

  1. Fine-scale flight strategies of gulls in urban airflows indicate risk and reward in city living

    PubMed Central

    Shepard, Emily L. C.

    2016-01-01

    Birds modulate their flight paths in relation to regional and global airflows in order to reduce their travel costs. Birds should also respond to fine-scale airflows, although the incidence and value of this remains largely unknown. We resolved the three-dimensional trajectories of gulls flying along a built-up coastline, and used computational fluid dynamic models to examine how gulls reacted to airflows around buildings. Birds systematically altered their flight trajectories with wind conditions to exploit updraughts over features as small as a row of low-rise buildings. This provides the first evidence that human activities can change patterns of space-use in flying birds by altering the profitability of the airscape. At finer scales still, gulls varied their position to select a narrow range of updraught values, rather than exploiting the strongest updraughts available, and their precise positions were consistent with a strategy to increase their velocity control in gusty conditions. Ultimately, strategies such as these could help unmanned aerial vehicles negotiate complex airflows. Overall, airflows around fine-scale features have profound implications for flight control and energy use, and consideration of this could lead to a paradigm-shift in the way ecologists view the urban environment. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528784

  2. Biochemical and Transcriptomic Effects of Herring Gull Egg Extracts from Variably Contaminated Colonies of the Laurentian Great Lakes in Chicken Hepatocytes.

    PubMed

    Crump, Doug; Williams, Kim L; Chiu, Suzanne; Letcher, Robert J; Periard, Luke; Kennedy, Sean W

    2015-08-18

    Determining the effects of complex mixtures of environmental contaminants poses many challenges within the field of ecotoxicology. In this study, graded concentrations of herring gull egg extracts, collected from five Great Lakes breeding colonies with variable burdens of organohalogen contaminants (OHCs), were administered to chicken embryonic hepatocytes to determine effects on 7-ethoxyresorufin-O-deethylase (EROD) activity, porphyrin accumulation, and mRNA expression. EROD activity and porphyrin accumulation permitted the ranking of colonies based on the efficacy of eliciting an aryl hydrocarbon receptor-mediated response. An avian ToxChip polymerase chain reaction (PCR) array provided more exhaustive coverage in terms of potential toxicity pathways being affected, including xenobiotic and lipid metabolism and the thyroid hormone pathway. Herring gull eggs from Channel Shelter Island (CHSH, Lake Huron) and Gull Island (GULL, Lake Michigan) had among the highest OHC burdens, and extracts elicited a biochemical and transcriptomic response greater than that of extracts from the other three, less polluted colonies. For example, EROD EC50 values and porphyrin ECthreshold values were lower for CHSH and GULL extracts than for the other colonies. Extracts from CHSH and GULL altered 15 and 13 of 27 genes on the PCR array compared to no more than eight genes for the less contaminated sites. The combination of a well-established avian in vitro assay, two well-characterized biochemical assays, and the avian ToxChip PCR array permitted the geographical discrimination of variably contaminated herring gull eggs from the Great Lakes. Such high-throughput assays show potential promise as cost-effective tools for determining toxic potencies of complex mixtures in the environment.

  3. 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

  4. The distribution and conservation status of the Gull-billed Tern (Gelochelidon nilotica) in North America

    USGS Publications Warehouse

    Molina, K.C.; Erwin, R.M.

    2006-01-01

    The Gull-billed Tern (Gelochelidon nilotica) has until recently received little conservation and management attention within North America despite a relatively low overall population size and significant declines in parts of the breeding range. This lack of attention may stem in part from the wide distribution of the species, encompassing parts of six continents, and from its tendency to nest in relatively small, scattered and often ephemeral colonies. Populations of North American subspecies are alarmingly small. The current population of the eastern subspecies aranea in the U.S. is unlikely to exceed 3,600 pairs, with over 60% of these birds occurring in Texas. The Texas population has remained generally stable, but declines of populations in Maryland (where probably extirpated), Virginia, North Carolina, Florida, and possibly Georgia give cause for concern for this subspecies. For the western subspecies vanrossemi, as few as 250 pairs nest at only two locations in the U.S., both in California. When populations in western Mexico are considered, the entire vanrossemi population numbers only 600-800 pairs. Currently the Gull-billed Tern is listed as ?endangered? or ?threatened? in four states, and is considered to be of management concern in five others. The breeding range of the species has contracted and shifted slightly from its known historic range in the middle Atlantic states, but otherwise occupies its historic range in the United States and has expanded slightly to coastal southern California. Some range contraction in Mexico (e.g., in Sonora) may have occurred. In eastern Mexico, historical information is almost non-existent and knowledge of current distribution and abundance is incomplete. Main threats to populations in North America include loss of natural nesting islands through beach erosion or perturbations to estuarine functions, development or modification of upland habitats near breeding areas that may be important for foraging, and disturbances to

  5. 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

  6. Geographical distribution of contaminants and productivity measures of herring gulls in the Great Lakes: Lake Erie and connecting channels 1978/79.

    PubMed

    Weseloh, D V; Mineau, P; Struger, J

    1990-02-01

    The distribution and size of colonies, residue levels of DDE, DDT, HCB, dieldrin, mirex and PCBs in eggs, productivity and eggshell thickness were determined for herring gulls at 14 sites in Lake Erie and connecting channels. The centre of distribution for breeding herring gulls was the Western Basin where approximately 90% of the 6200 nests in the study area were located. Seven of 22 colonies showed an average annual population increase of 48.3%. Most of the increase in breeding herring gulls on Lake Erie is directly associated with sites that have undergone habitat modification by man. Levels of PCBs and DDE ranged from 35 to 140 ppm (wet weight) and from 2.8 to 9.4 ppm, respectively; all other residues were less than 0.49 ppm. Most organochlorine residue levels were highest in eggs from colonies in or near the Niagara or Detroit Rivers. Mirex residues were greatest in the Niagara River and decreased significantly to the west. PCB residues were greatest in the Detroit River and decreased significantly to the east. The lowest levels generally came from colonies in the Sandusky Basin and near Pelee Island in western Lake Erie. Discriminant function analysis of six organochlorine contaminants correctly classified 90% or more of the eggs from up to four colonies in one or more years. Levels of PCBs and HCB appeared to have the greatest discriminating power. Herring gull productivity at all colonies (1-1.7 young gulls/pair) was normal and showed no significant geographical variation. Eggshell thickness was greatest in colonies in the Sandusky Basin and least in colonies in the Detroit River and extreme west end of the lake; mean eggshell thickness was 0.350 +/- 0.02 mm (6.7% thinning), which was weakly, but significantly correlated to DDE concentration. The variation in contaminants in herring gull eggs on a Basin basis (i.e., Western, Eastern, Sandusky, etc.) paralleled those known for sediments, water and fish. Thus, we suggest that in addition to its role as an

  7. 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.

  8. Genetic structure, diversity and subspecies status of Gull-billed Terns (Gelochelidon nilotica) from the United States

    USGS Publications Warehouse

    Miller, Mark P.; Mullins, Thomas D.; Haig, Susan M.

    2013-01-01

    Gull-billed Terns (Gelochelidon nilotica) are among the most widespread, yet scarce, Charadriiformes in the world. Two subspecies are recognized in the United States: G. n. aranea breeds along the U.S. Atlantic and Gulf coasts and G. n. vanrossemi breeds in the Salton Sea and San Diego Bay of California. Conservation concerns exist for the species due to its low abundance in the United States and apparent declines in some parts of its North American range. We used nuclear microsatellite markers and mitochondrial DNA sequences to assess genetic diversity and differentiation patterns among Gull-billed Tern populations from Virginia, Texas, and California. We also tested for evidence of population bottlenecks, and evaluated the support our data provide for the North American subspecies. Genetic diversity was highest in Texas and underscored the importance of habitat in that large population. Significant population differentiation existed, but could not be consistently identified using various analytical approaches and suggested that the magnitude of differentiation was low. No evidence for bottlenecks was identified. Our data could not distinguish individuals from different subspecies and therefore do not support the current intraspecific taxonomy. Tenable explanations for many findings are related to the low site tenacity demonstrated by the species.

  9. Population recovery and natural recruitment of lake trout at Gull Island Shoal, Lake Superior, 1964-1992

    USGS Publications Warehouse

    Schram, Stephen T.; Selgeby, James H.; Bronte, Charles R.; Swanson, Bruce L.

    1995-01-01

    We documented an increase in the abundance of wild lake trout (Salvelinus namaycush) at Gull Island Shoal in western Lake Superior and examined the relationship between parental-stock size and recruitment of age-0 fish in 1964–1992. Abundance of adult wild female lake trout and densities of age-0 fish both increased during the 28-year period. A significant positive, linear relationship (P = 0.0002) was found between the abundance of wild females on the spawning reef in the fall and density of age-0 lake trout on adjacent nursery grounds in August and September of the following year. The abundance of hatchery-origin females did not explain significant amounts (P = 0.107) of variation in recruitment. We concluded that most recruitment in 1965–1992 was the result of natural reproduction of wild females. After 28 years of recovery the Gull Island Shoal lake trout population appears to have additional capacity to increase because the stock-recruitment relationship is still linear. Therefore, restoration periods on the order of 30 years may be needed for other lake trout populations in the Great Lakes. We recommend that the refuge established to protect this population be maintained to allow further study of the relationship between parental stock and recruitment, and to provide a major source of recruitment to the lake trout population in the surrounding waters

  10. Hatching, dispersal, and bathymetric distribution of age-0 wild lake trout at the Gull Island Shoal complex, Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Selgeby, James H.; Saylor, James H.; Miller, Gerald S.; Foster, Neal R.

    1995-01-01

    We studied age-0 lake trout (Salvelinus namaycush) associated with spawning and nursery areas of the Gull Island Shoal complex in western Lake Superior. Post-emergent age-0 lake trout were captured on rocky spawning substrate with a 3-m beam trawl and at the nursery area with a bottom trawl from June to September 1990 and June to August 1991. Catch data suggested that age-0 lake trout move distances of 7–11 km to the nursery area over a 3-month period. Water currents, measured at Gull Island Shoal, may be a part of the transport mechanism. Examination of daily-growth increments on the sagittae and back-calculation from the date of capture revealed that most fish hatched between 6 June and 19 July in 1990 and between 30 April and 30 May in 1991. The duration of the hatch was 100 days in 1990 and 120 days in 1991, and the estimated incubation period is about 7 months for lake trout eggs at this site. Similar hatch-date distributions of age-0 captured on different sampling dates suggested that natural mortality was low.

  11. Modeling colony site dynamics: a case study of gull-billed terns (Sterna nilotica) in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Nichols, J.D.; Eyler, T.B.; Stotts, D.B.; Truitt, B.R.

    1998-01-01

    We developed a Markov process model for colony site dynamics of Gull-billed Terns (Sterna nilotica) in coastal Virginia. We used the model and data on colony site occupation from 1993 to 1996 to estimate model parameters. Each year, we monitored the breeding numbers of Gull-billed Terns and their frequent colony associates, Common Terns (Sterna hirundo) and Black Skimmers (Rynchops niger) at colony sites along about 80 km of the barrier island region of Virginia. We also monitored flooding events and renesting. We developed the model for colony survival, extinction, and recolonization at potential colony sites over the four-year period. We then used data on annual site occupation by Gull-billed Terns to estimate model parameters and test between different structures reflecting competing hypotheses. Results revealed a dynamic system, but provided no evidence that the dynamics were Markovian , i.e. the probability of occupancy of a site in one year was not influenced by whether it had been occupied the previous year. Nor did the colony-level reproductive success the previous season seem to affect the probability of site occupancy. Site survival and recolonization rates were similar, and the overall annual probability of a site being occupied over the course of the four-year period was estimated to be 0.59 Of the total of 25 sites that were used during the four-year period, 16 were used in only one or two years while only three were used all four years.. Flooding and renesting were frequent in both habitat types in all years. The frequent flooding of nests on shellpiles argues for more effective management; augmentation with shell and sand to increase elevations as little as 20 cm could have reduced flooding at a number of sites. The low colony-site fidelity we demonstrate suggests that an effective management approach is to provide a large number of alternative sand and/or shellpile sites that the terns may use. Sites not used one year may still be used in subsequent

  12. Investigation of suspected gulls in the Jurassic limestone strata of the Cotswold Hills, Gloucestershire, England using electrical resistivity tomography

    NASA Astrophysics Data System (ADS)

    Barron, A. J. M.; Uhlemann, S.; Pook, G. G.; Oxby, L.

    2016-09-01

    An electrical resistivity tomography survey has clearly indicated the presence of substantial vertical zones of contrasting material beneath a set of conspicuous linear surface hollows that cut across a spur forming part of the Cotswold Hills escarpment in Gloucestershire. These zones are compared with nearby quarry exposures and are inferred to be gulls - graben-like structures at least 80 m deep filled with collapsed blocks of bedrock with intervening air-filled spaces, lying within areas of relatively undisrupted gently dipping strata, and which under some circumstances would present a significant geohazard. Our results confirm the great potential of this non-invasive and rapid survey technique for investigating such phenomena, and provide an exemplar for comparison with surveys elsewhere, to assist identification of similar features.

  13. Species-specific time trends and enantiomer fractions of hexabromocyclododecane (HBCD) in biota from East Greenland.

    PubMed

    Vorkamp, Katrin; Bester, Kai; Rigét, Frank F

    2012-10-02

    Time trends of hexabromocyclododecane (HBCD) isomers were studied for glaucous gull and ringed seal from East Greenland. The ringed seal results extended a previous time trend (1986-2008) to 2010. α-HBCD was the only isomer consistently above quantification limits. For glaucous gull liver, annual median values of α-HBCD (1994-2010) ranged from 22 to 120 ng/g lipid weight (lw) with no significant trend, while HBCD in ringed seal blubber from the same area showed a significant increase from 3.9 to 11 ng/g lw (1986-2010). Reasons for this difference are unknown, but might include different feeding habits and species-specific metabolisation processes. Concentrations of several organochlorine (OC) compounds were determined for glaucous gull and ringed seal samples collected from the same area in 2004. HBCD concentrations in glaucous gull liver appeared relatively low when compared to OC concentrations in the same tissue and to both HBCD and OCs in ringed seal blubber from the same area. Enantiomer fractions (EF) deviated significantly from racemic for all annual mean EFs in glaucous gull suggesting metabolisation processes toward an enrichment of (-)α-HBCD. For ringed seal, this enrichment was less pronounced and only significant for two of the ten years. For neither species, significant changes in EF were found over time.

  14. Characterization of Newcastle disease viruses isolated from cormorant and gull species in the United States in 2010.

    PubMed

    Diel, Diego G; Miller, Patti J; Wolf, Paul C; Mickley, Randall M; Musante, Anthony R; Emanueli, Daniel C; Shively, Kirk J; Pedersen, Kerri; Afonso, Claudio L

    2012-03-01

    Newcastle disease virus (NDV), a member of the genus Avulavirus of the family Paramyxoviridae, is the causative agent of Newcastle disease (ND), a highly contagious disease that affects many species of birds and which frequently causes significant economic losses to the poultry industry worldwide. Virulent NDV (vNDV) is exotic in poultry in the United States; however, the virus has been frequently associated with outbreaks of ND in cormorants, which poses a significant threat to poultry species. Here, we present the characterization of 13 NDV isolates obtained from outbreaks of ND affecting cormorants and gulls in the states of Minnesota, Massachusetts, Maine, New Hampshire, and Maryland in 2010. All 2010 isolates are closely related to the viruses that caused the ND outbreaks in Minnesota in 2008, following the new evolutionary trend observed in cormorant NDV isolates since 2005. Similar to the results obtained with the 2008 isolates, the standard United States Department of Agriculture F-gene real-time reverse-transcription PCR (RRT-PCR) assay failed to detect the 2010 cormorant viruses, whereas all viruses were detected by a cormorant-specific F-gene RRT-PCR assay. Notably, NDV-positive gulls were captured on the eastern shore of Maryland, which represents a significant geographic expansion of the virus since its emergence in North America. This is the first report of vNDV originating from cormorants isolated from wild birds in Maryland and, notably, the first time that genotype V vNDV has been isolated from multiple wild bird species in the United States. These findings highlight the need for constant epidemiologic surveillance for NDV in wild bird populations and for consistent biosecurity measures to prevent the introduction of the agent into domestic poultry flocks.

  15. Whole-Genome Sequencing Analysis of Salmonella enterica Serovar Enteritidis Isolates in Chile Provides Insights into Possible Transmission between Gulls, Poultry, and Humans

    PubMed Central

    Ayers, Sherry; Barreto, Marlen; Allard, Marc; Brown, Eric W.

    2016-01-01

    ABSTRACT Salmonella enterica subsp. enterica serotype Enteritidis is a major cause of human salmonellosis worldwide; however, little is known about the genetic relationships between S. Enteritidis clinical strains and S. Enteritidis strains from other sources in Chile. We compared the whole genomes of 30 S. Enteritidis strains isolated from gulls, domestic chicken eggs, and humans in Chile, to investigate their phylogenetic relationships and to establish their relatedness to international strains. Core genome multilocus sequence typing (cgMLST) analysis showed that only 246/4,065 shared loci differed among these Chilean strains, separating them into two clusters (I and II), with cluster II being further divided into five subclusters. One subcluster (subcluster 2) contained strains from all surveyed sources that differed at 1 to 18 loci (of 4,065 loci) with 1 to 18 single-nucleotide polymorphisms (SNPs), suggesting interspecies transmission of S. Enteritidis in Chile. Moreover, clusters were formed by strains that were distant geographically, which could imply that gulls might be spreading the pathogen throughout the country. Our cgMLST analysis, using other S. Enteritidis genomes available in the National Center for Biotechnology Information (NCBI) database, showed that S. Enteritidis strains from Chile and the United States belonged to different lineages, which suggests that S. Enteritidis regional markers might exist and could be used for trace-back investigations. IMPORTANCE This study highlights the importance of gulls in the spread of Salmonella Enteritidis in Chile. We revealed a close genetic relationship between some human and gull S. Enteritidis strains (with as few as 2 of 4,065 genes being different), and we also found that gull strains were present in clusters formed by strains isolated from other sources or distant locations. Together with previously published evidence, this suggests that gulls might be spreading this pathogen between different regions

  16. 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.

  17. 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.

  18. 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.

  19. Adapting to a Changing World: Unraveling the Role of Man-Made Habitats as Alternative Feeding Areas for Slender-Billed Gull (Chroicocephalus genei)

    PubMed Central

    Ramírez, Francisco; Navarro, Joan; Afán, Isabel; Hobson, Keith A.; Delgado, Antonio; Forero, Manuela G.

    2012-01-01

    Current rates of wildlife habitat loss have placed increasing demands on managers to develop, validate and implement tools aimed at improving our ability to evaluate such impacts on wildlife. Here, we present a case study conducted at the Natural Area of Doñana (SW Spain) where remote sensing and stable isotope (δ13C, δ15N) analyses of individuals were combined to unravel (1) the effect of variations in availability of natural food resources (i.e. from natural marshes) on reproductive performance of a Slender-billed Gull (Chroicocephalus genei) population, and (2) the role of two adjacent, artificial systems (a fish farm and saltmines) as alternate anthropogenic feeding areas. Based on long-term (1983–2004) remote-sensing, we inferred the average extent of flooded area at the marshland (a proxy to natural resource availability) annually. Estimated flooded areas (ranging from extreme drought [ca. 151 ha, 1995] to high moisture [15,049 ha, 2004]) were positively related to reproductive success of gulls (estimated for the 1993–2004 period, and ranging from ca. 0 to 1.7 fledglings per breeding pairs), suggesting that habitat availability played a role in determining their reproductive performance. Based on blood δ13C and δ15N values of fledglings, 2001–2004, and a Bayesian isotopic mixing model, we conclude that saltmines acted as the main alternative foraging habitat for gulls, with relative contributions increasing as the extent of marshland decreased. Although adjacent, anthropogenic systems have been established as the preferred breeding sites for this gull population, dietary switches towards exploitation of alternative (anthropogenic) food resources negatively affected the reproductive output of this species, thus challenging the perception that these man-made systems are necessarily a reliable buffer against loss of natural feeding habitats. The methodology and results derived from this study could be extended to a large suite of threatened natural

  20. Molecular characterization and genetic diversity of ESBL-producing Escherichia coli colonizing the migratory Franklin's gulls (Leucophaeus pipixcan) in Antofagasta, North of Chile.

    PubMed

    Báez, John; Hernández-García, Marta; Guamparito, Constanza; Díaz, Sofía; Olave, Abdon; Guerrero, Katherine; Cantón, Rafael; Baquero, Fernando; Gahona, Joselyne; Valenzuela, Nicomedes; Del Campo, Rosa; Silva, Juan

    2015-02-01

    The role of wild animals, particularly migratory birds, in the dissemination of antibiotic-resistant bacteria between geographically distant ecosystems is usually underestimated. The aim of this work was to characterize the Escherichia coli population from Franklin's gull feces, focusing on the extended-spectrum β-lactamase (ESBL)-producing strains. In the summer of 2011, 124 fecal swabs from seagulls (1 of each) migrating from the United States and Canada to the coast of Antofagasta, north of Chile, were collected. Samples were seeded on MacConkey agar supplemented with 2 μg/ml of cefotaxime and a single colony from each plate was tested for ESBL production by the double-disk ESBL synergy test. Antibiotic susceptibility was determined by the disk diffusion method and blaESBL genes were amplified and sequenced. The genetic diversity of isolates was explored by pulsed-field gel electrophoresis (PFGE)-XbaI and multilocus sequence typing. A total of 91 E. coli isolates with high rates of antibiotic resistance were identified. Carbapenemase production was not detected, whereas 67 of the 91 (54%) isolates exhibited an ESBL phenotype due to the presence of CTX-M-15 (61.3%), CTX-M-2 (19.3%), CTX-M-22 (16.1%), and CTX-M-3 (1.6%) coding genes. High genetic diversity was observed, with 30 PFGE patterns and 23 sequence types (STs), including ST131 (18%), ST44 (15%), ST617 (9%), and ST10 (9%). Results presented here are complementary to those previously reported by Hernández et al. in the same gull species, but located in the Central Region of Chile. Differences observed between gulls from both areas lead us to hypothesize that gulls from the northern location retain, as gut carriers, those resistant bacteria acquired in the United States and/or Canada.

  1. The gull (Chroicocephalus brunnicephalus) as an environmental bioindicator and reservoir for antibiotic resistance on the coastlines of the Bay of Bengal.

    PubMed

    Hasan, Badrul; Melhus, Åsa; Sandegren, Linus; Alam, Munirul; Olsen, Björn

    2014-10-01

    The presence and frequency of multiresistant bacteria in wild birds act as indicators of the environmental contamination of antibiotic resistance. To explore the rate of contamination mediated by Escherichia coli, 150 fecal samples from the brown-headed gull (Chroicocephalus brunnicephalus) and 8 water samples from the Bay of Bengal area were collected, cultured, and tested for antibiotic susceptibility. Special attention was paid to extended-spectrum beta-lactamase (ESBL)-producing isolates, which were further characterized genetically. Antibiotic resistance was found in 42.3% (36/85) of the E. coli isolates and multidrug resistance in 11.8%. Isolates from the area with a higher human activity were more resistant than those from an area with a lower level of activity. Most frequent was resistance to ampicillin (29.4%), followed by trimethoprim-sulfamethoxazole (24.7%) and quinolones (22.4%). Carriage of ESBL-producing E. coli was relatively high (17.3%) in the gulls, whereas no ESBL producers were found in the water. All ESBL-producing E. coli isolates, but one, carried bla(CTX-M-15) or bla(CTX-M-15)-like genes. A bla(CTX-M-14)-like enzyme was found as an exception. Gulls from two different colonies shared E. coli clones and harbored the clinically relevant sequence types ST10, ST48, and ST131. The high frequency of antibiotic resistance and ESBL production among E. coli isolates from gulls indicates that the environmental contamination of antibiotic resistance has already gone far on the coastlines of the Bay of Bengal. Considering the limited control over the antibiotic consumption and waste from human activities in Bangladesh, there is no easy solution in sight.

  2. Veterinary Research Manpower Development for Defense

    DTIC Science & Technology

    2009-09-01

    experience Sarah Raabis V’12 Dr. E. Brum Sustainable Food Security and Rural Family Livelihoods: A Descriptive Evaluation of Small-Scale...1. Streptomycin, ampicillin and tetracycline resistant isolates were the most prevalent type of resistance phenotypes in both gull and wastewater ...cultured from wild Herring Gulls (Larus argentatus) and from human wastewater at Cape Cod, Massachusetts. Bacterial sensitivity was tested with

  3. Whole-Genome Sequencing Analysis of Salmonella enterica Serovar Enteritidis Isolates in Chile Provides Insights into Possible Transmission between Gulls, Poultry, and Humans.

    PubMed

    Toro, Magaly; Retamal, Patricio; Ayers, Sherry; Barreto, Marlen; Allard, Marc; Brown, Eric W; Gonzalez-Escalona, Narjol

    2016-10-15

    Salmonella enterica subsp. enterica serotype Enteritidis is a major cause of human salmonellosis worldwide; however, little is known about the genetic relationships between S Enteritidis clinical strains and S Enteritidis strains from other sources in Chile. We compared the whole genomes of 30 S Enteritidis strains isolated from gulls, domestic chicken eggs, and humans in Chile, to investigate their phylogenetic relationships and to establish their relatedness to international strains. Core genome multilocus sequence typing (cgMLST) analysis showed that only 246/4,065 shared loci differed among these Chilean strains, separating them into two clusters (I and II), with cluster II being further divided into five subclusters. One subcluster (subcluster 2) contained strains from all surveyed sources that differed at 1 to 18 loci (of 4,065 loci) with 1 to 18 single-nucleotide polymorphisms (SNPs), suggesting interspecies transmission of S Enteritidis in Chile. Moreover, clusters were formed by strains that were distant geographically, which could imply that gulls might be spreading the pathogen throughout the country. Our cgMLST analysis, using other S Enteritidis genomes available in the National Center for Biotechnology Information (NCBI) database, showed that S Enteritidis strains from Chile and the United States belonged to different lineages, which suggests that S Enteritidis regional markers might exist and could be used for trace-back investigations.

  4. Migratory Connectivity at High Latitudes: Sabine’s Gulls (Xema sabini) from a Colony in the Canadian High Arctic Migrate to Different Oceans

    PubMed Central

    Davis, Shanti E.; Maftei, Mark; Mallory, Mark L.

    2016-01-01

    The world's Arctic latitudes are some of the most recently colonized by birds, and an understanding of the migratory connectivity of circumpolar species offers insights into the mechanisms of range expansion and speciation. Migratory divides exist for many birds, however for many taxa it is unclear where such boundaries lie, and to what extent these affect the connectivity of species breeding across their ranges. Sabine’s gulls (Xema sabini) have a patchy, circumpolar breeding distribution and overwinter in two ecologically similar areas in different ocean basins: the Humboldt Current off the coast of Peru in the Pacific, and the Benguela Current off the coasts of South Africa and Namibia in the Atlantic. We used geolocators to track Sabine’s gulls breeding at a colony in the Canadian High Arctic to determine their migratory pathways and wintering sites. Our study provides evidence that birds from this breeding site disperse to both the Pacific and Atlantic oceans during the non-breeding season, which suggests that a migratory divide for this species exists in the Nearctic. Remarkably, members of one mated pair wintered in opposite oceans. Our results ultimately suggest that colonization of favorable breeding habitat may be one of the strongest drivers of range expansion in the High Arctic. PMID:27973614

  5. 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

  6. 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

  7. Characterization and Comparison of Extended-Spectrum β-Lactamase (ESBL) Resistance Genotypes and Population Structure of Escherichia coli Isolated from Franklin's Gulls (Leucophaeus pipixcan) and Humans in Chile

    PubMed Central

    Stedt, Johan; Bengtsson, Stina; Porczak, Aleksandra; Granholm, Susanne; González-Acuña, Daniel; Olsen, Björn; Bonnedahl, Jonas; Drobni, Mirva

    2013-01-01

    We investigated the general level of antibiotic resistance with further analysis of extended-spectrum beta-lactamase (ESBL) prevalence, as well as the population structure of E. coli in fecal flora of humans and Franklin’s gulls (Leucophaeus pipixcan) in central parts of Chile. We found a surprisingly high carriage rate of ESBL-producing E. coli among the gulls 112/372 (30.1%) as compared to the human population 6/49 (12.2%.) Several of the E. coli sequence types (STs) identified in birds have previously been reported as Multi Drug Resistant (MDR) human pathogens including the ability to produce ESBLs. This means that not only commensal flora is shared between birds and humans but also STs with pathogenic potential. Given the migratory behavior of Franklin’s gulls, they and other migratory species, may be a part of ESBL dissemination in the environment and over great geographic distances. Apart from keeping the antibiotic use low, breaking the transmission chains between the environment and humans must be a priority to hinder the dissemination of resistance. PMID:24098774

  8. Contaminants of emerging concern in Caspian tern compared to herring gull eggs from Michigan colonies in the Great Lakes of North America.

    PubMed

    Su, Guanyong; Letcher, Robert J; Moore, Jeremy N; Williams, Lisa L; Grasman, Keith A

    2017-03-01

    A broad suite of 87 contaminants of emerging concern (CECs), including 26 polybrominated diphenyl ethers (PBDEs), 23 non-PBDEs halogenated FRs (NPHFRs), 16 organophosphate esters (OPEs), 4 perfluorinated sulfonates (PFSAs), 13 perfluorinated carboxylic acids (PFCAs) and 5 emerging perfluoroalkyl acids (PFAAs) or precursors, were determined in 30 individual Caspian tern (listed as a threatened species in the U.S. State of Michigan) eggs collected in 2013 and 2014 from Michigan nesting sites on Two Tree Island (St, Mary's River), Charity Reef (Saginaw Bay) and Channel-Shelter Island (a Confined Disposal Facility (CDF) in Saginaw Bay). The same CEC suite was determined in 10 herring gull eggs on the Pipe Island Twins in the lower St. Mary's River. In tern eggs, the order of concentrations were ΣPFSA (mean: 793 ng/g wet weight (ww); range: 116-4690 ng/g ww) > ΣPFCAs (131; 30.4-506 ng/g ww) ≈ ΣPBDEs (86.7; 32.4-189 ng/g ww) » ΣNPHFRs (0.67; ND-4.3 ng/g ww) ≈ ΣOPEs (0.46; ND-2.89 ng/g ww). Compared to gull eggs collected from the same area, tern egg exposure contained significantly lower concentrations of ΣPBDE, but with up to 10 times greater mean concentrations of ΣPFSAs and ΣPFCAs. This study highlights the importance of consistent monitoring in eggs of different Great Lakes birds of PBDEs, perfluorooctane sulfonate (PFOS) and perfluoro-4-ethylcyclohexane sulfonate (PFEtCHxS) given that: 1) PBDE concentrations in all analyzed avian eggs exceeded or approached a concentration of 29 ng/g ww, which for birds is the current Canadian FEQG (Federal Environmental Quality Guideline); 2) ΣPBDE concentrations were comparable to lowest observed effect concentration (LOEC) values reported in the literature; 3) PFOS concentrations in Caspian tern eggs were extremely high with many eggs across sites exceeding 1 ppm, and with the greatest being up to 4.7 ppm; and 4) PFEtCHxS, a potentially persistent and bioaccumulative substance, showed a detection

  9. White-faced storm-petrels Pelagodroma marina predated by gulls as biological monitors of plastic pollution in the pelagic subtropical Northeast Atlantic.

    PubMed

    Furtado, Ricardo; Menezes, Dilia; Santos, Carolina Jardim; Catry, Paulo

    2016-11-15

    Marine plastic pollution is rapidly growing and is a source of major concern. Seabirds often ingest plastic debris and are increasingly used as biological monitors of plastic pollution. However, virtually no studies have assessed plastics in seabirds in the deep subtropical North Atlantic. We investigated whether remains of white-faced storm-petrels (WFSP) present in gull pellets could be used for biomonitoring. We analysed 263 pellets and 79.0% of these contained plastic debris originating in the digestive tract of WFSP. Pellets with no bird prey did not contain plastics. Most debris were fragments (83.6%) with fewer plastic pellets (8.2%). Light-coloured plastics predominated (71.0%) and the most frequent polymer was HDPE (73.0%). Stable isotopes in toe-nails of WFSP containing many versus no plastics did not differ, indicating no individual specialisation leading to differential plastic ingestion. We suggest WFSP in pellets are highly suitable to monitor the little known pelagic subtropical Northeast Atlantic.

  10. Detection limits and cost comparisons of human- and gull-associated conventional and quantitative PCR assays in artificial and environmental waters

    USGS Publications Warehouse

    Riedel, Timothy E.; Zimmer-Faust, Amity G.; Thulsiraj, Vanessa; Madi, Tania; Hanley, Kaitlyn T.; Ebentier, Darcy L.; Byappanahalli, Muruleedhara N.; Layton, Blythe; Raith, Meredith; Boehm, Alexandria B.; Griffith, John F.; Holden, Patricia A.; Shanks, Orin C.; Weisberg, Stephen B.; Jay, Jennifer A.

    2014-01-01

    Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. For human-associated assays targeting Bacteroidales HF183 genetic marker, qPCR LODs were 70 times lower and there was no effect of target matrix (artificial freshwater, environmental creek water, and environmental marine water) on PCR or qPCR LODs. The PCR startup and annual costs were the lowest, while the per reaction cost was 62% lower than the Taqman based qPCR and 180% higher than the SYBR based qPCR. For gull-associated assays, there was no significant difference between PCR and qPCR LODs, target matrix did not effect PCR or qPCR LODs, and PCR startup, annual, and per reaction costs were lower. Upgrading to qPCR involves greater startup and annual costs, but this increase may be justified in the case of the human-associated assays with lower detection limits and reduced cost per sample.

  11. Detection limits and cost comparisons of human- and gull-associated conventional and quantitative PCR assays in artificial and environmental waters.

    PubMed

    Riedel, Timothy E; Zimmer-Faust, Amity G; Thulsiraj, Vanessa; Madi, Tania; Hanley, Kaitlyn T; Ebentier, Darcy L; Byappanahalli, Muruleedhara; Layton, Blythe; Raith, Meredith; Boehm, Alexandria B; Griffith, John F; Holden, Patricia A; Shanks, Orin C; Weisberg, Stephen B; Jay, Jennifer A

    2014-04-01

    Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. For human-associated assays targeting Bacteroidales HF183 genetic marker, qPCR LODs were 70 times lower and there was no effect of target matrix (artificial freshwater, environmental creek water, and environmental marine water) on PCR or qPCR LODs. The PCR startup and annual costs were the lowest, while the per reaction cost was 62% lower than the Taqman based qPCR and 180% higher than the SYBR based qPCR. For gull-associated assays, there was no significant difference between PCR and qPCR LODs, target matrix did not effect PCR or qPCR LODs, and PCR startup, annual, and per reaction costs were lower. Upgrading to qPCR involves greater startup and annual costs, but this increase may be justified in the case of the human-associated assays with lower detection limits and reduced cost per sample.

  12. Miscellaneous pocosin peat deposits of North Carolina: Gull Rock; Van Swamp; Bay City - Gum Swamp. Open-grounds pocos in Hofmann Forest; Angola Swamp; Holly Shelter; Green Swamp

    SciTech Connect

    Ingram, R.L.; Otte, L.J.; Witner, T.W.

    1983-06-01

    In earlier reports the coastal swamp or pocosin peat deposits of Dismal Swamp, Pamlimarle Peninsula, Croatan Forest, and Light Ground Pocosin were described (Ingram and Otte, 1980, 1981a, 1981b, and 1982). This report describes the remaining coastal swamp or pocosin deposits of the North Carolina Coastal Plain. Total peat resources of these remaining deposits are: (1) Gull Rock - 8100 acres, 4.6 million tons, moisture free, (2) Van Swamp - 6600 acres, 5.8 million tons, (3) Bay City - Gum Swamp - 12,3000 acres, 5.9 million tons, (4) Open Grounds - 11,000 acres, 6.3 million tons, (5) Hofmann Forest - 5200 acres, 4.2 million tons, (6) Angola Swamp - 21,900 acres, 15.2 million tons, (7) Holly Shelter - 9200 acres, 6.7 million tons, and (8) Green Swamp - 16,400 acres, 10.3 million tons. A revised estimation of the total peat resources of North Carolina is 700,000 acres (1100 sq mi) of peatland with 500 million tons of peat. Of this total, 290,000 acres (460 sq mi) is underlain by peat greater than 4 ft thick with 330 million tons of peat.

  13. Age of first breeding interacts with pre- and post-recruitment experience in shaping breeding phenology in a long-lived gull.

    PubMed

    Bosman, Davy S; Vercruijsse, Harry J P; Stienen, Eric W M; Vincx, Magda; Lens, Luc

    2013-01-01

    Individual variation in timing of breeding is a key factor affecting adaptation to environmental change, yet our basic understanding of the causes of such individual variation is incomplete. This study tests several hypotheses for age-related variation in the breeding timing of Lesser Black-backed Gulls, based on a 13 year longitudinal data set that allows to decouple effects of age, previous prospecting behavior, and years of breeding experience on arrival timing at the colony. At the population level, age of first breeding was significantly associated with timing of arrival and survival, i.e. individuals tended to arrive later if they postponed their recruitment, and individuals recruiting at the age of 4 years survived best. However, up to 81% of the temporal variation in arrival dates was explained by within-individual effects. When excluding the pre-recruitment period, the effect of increasing age on advanced arrival was estimated at 11 days, with prior breeding experience accounting for a 7 days advance and postponed breeding for a 4 days delay. Overall, results of this study show that delayed age of first breeding can serve to advance arrival date (days after December 1(st)) in successive breeding seasons throughout an individual's lifetime, in large part due to the benefits of learning or experience gained during prospecting. However, prospecting and the associated delay in breeding also bear a survival cost, possibly because prospectors have been forced to delay through competition with breeders. More generally, results of this study set the stage for exploring integrated temporal shifts in phenology, resource allocation and reproductive strategies during individual lifecycles of long-lived migratory species.

  14. Comprehensive re-analysis of archived herring gull eggs reconstructs historical temporal trends in chlorinated hydrocarbon contamination in Lake Ontario and Green Bay, Lake Michigan, 1971-1982.

    PubMed

    Norstrom, Ross J; Hebert, Craig E

    2006-08-01

    Herring gull egg homogenates collected between 1971 and 1982 from a colony in central Lake Ontario (Scotch Bonnet Island) and from a colony in central Green Bay, Lake Michigan (Big Sister Island) were archived in the Canadian Wildlife Service Specimen Bank. Pooled samples (N = 10) were exhaustively analyzed in 1993 for a wide range of individual chlorinated hydrocarbon contaminant (CHC) compounds: DDT, mirex and chlordane compounds and metabolites, chlorobenzenes (CBzs), dieldrin, chlorostyrenes (CSs), hexachlorocyclohexanes (HCHs), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and 87 PCB congeners, including the TCDD-like non-ortho and mono-ortho congeners. PCBs and DDTs were the dominant residues in eggs from both Lake Ontario (31-242 mg kg(-1) and 9-64 mg kg(-1)) and Green Bay (34-133 mg kg(-1) and 14-91 mg kg(-1)). SigmaPCBs declined by a factor of 4-5 and DDTs a factor of 4-7 at both colonies between 1971 and 1982. Lake Ontario eggs had significantly higher residues of 2,3,7,8-TCDD (0.2-2.0 microg kg(-1)), HCBz (0.1-4.7 mg kg(-1)), OCS (0.03-0.45 mg kg(-1)), three HpCSs (0.13-0.97 mg kg(-1)), mirex and mirex photodegradation products (2.1-9.2 mg kg(-1)) than Green Bay eggs. HCBz levels in Lake Ontario eggs declined a factor of 40, TCDD and chlorostyrenes a factor of 8-10, and mirex a factor of 4 between 1971-1978. Green Bay eggs had slightly higher levels of chlordane-related compounds, dieldrin and beta-HCH than Lake Ontario eggs. There were no consistent or strong trends in residue levels of these pesticides, PCDDs (except TCDD) and PCDFs in either lake, indicating that rates of input and removal of these CHCs in the lakes were much closer in the early 1970s than was the case for the other compounds.

  15. Organochlorine residues in eggs of Alaskan seabirds

    USGS Publications Warehouse

    Ohlendorf, H.M.; Bartonek, J.C.; Divoky, G.J.; Klass, E.

    1982-01-01

    One egg from each of 440 clutches of eggs of 19 species of Alaskan seabirds collected in 1973-76 was analyzed for organochlorine residues. All eggs contained DDE; 98.9% contained PCB's; 84.3%, oxychlordane; and 82.7%, HCB. Endrin was found in only one egg, but DDD, DDT, dieldrin, heptachlor epoxide, mirex, cis-chlordane (or trans-nonachlor), cis-nonachlor, and toxaphene each occurred in at least 22% of the samples.Concentrations of organochlorines in the samples were generally low. Mean concentrations of eight compounds were highest in eggs of glaucous-winged gulls (Larus glaucescens) from three sites: DDE (5.16 ppm, wet weight), dieldrin (0.214 ppm), oxychlordane (0.251 ppm), and PCB's (3.55 ppm) in eggs from Bogoslof Island; heptachlor epoxide (0.037 ppm), cis-chlordane (0.075 ppm), and HCB (0.188 ppm) in eggs from Buldir Island; and cis-nonachlor (0.026 ppm) in eggs from the Semidi Islands. Highest concentrations of DDD (0.157 ppm), DDT (0.140 ppm), and toxaphene (0.101 ppm) were in eggs of fork-tailed storm-petrel (Oceanodroma furcata) from Buldir Island, and the highest concentration of mirex (0.044 ppm) was in fork-tailed storm-petrel eggs from the Barren Islands.Both frequency of occurrence and concentration of residues in the eggs differed geographically and by species, apparently reflecting non-uniform distribution of organochlorines in the environment, dissimilar feeding habits and migration patterns of the species, or metabolic differences among the species.The overall frequency of residue occurrence was highest in eggs from the Pribilof Islands, but only three species were represented in the samples collected there. Detectable residues also were more frequent in eggs from the Gulf of Alaska colonies than elsewhere, and the lowest frequency was in eggs from nesting colonies on or near the Seward Peninsula. Regionally, concentrations of DDE and PCB's were usually higher than average in eggs from the Gulf of Alaska and lower than average in eggs from the

  16. 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.

  17. Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: inferences from spatial and trophic variation.

    PubMed

    Ricca, Mark A; Keith Miles, A; Anthony, Robert G

    2008-11-15

    Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an additional 8 seabird species representing different foraging and migratory guilds from Buldir Island to evaluate: 1) point source input from former military installations, 2) westward increases in contaminant concentrations suggestive of distant source input, and 3) effects of trophic status (delta15N) and carbon source (delta13C) on contaminant accumulation. Concentrations of Sigma polychlorinated biphenyls (PCBs) and most chlorinated pesticides in glaucous-winged gulls consistently exhibited a 'U'-shaped pattern of high levels at Buldir and the east side of Adak and low levels at Kiska and Amchitka. In contrast, concentrations of Sigma PCBs and chlorinated pesticides in northern fulmars and tufted puffins did not differ among islands. Hg concentrations increased westward in glaucous-winged gulls and were highest in northern fulmars from Buldir. Among species collected only at Buldir, Hg was notably elevated in pelagic cormorants, and relatively high Sigma PCBs were detected in black-legged kittiwakes. Concentrations of Sigma PCBs, dichlorodiphenyldichloroethylene (p,p' DDE), and Hg were positively correlated with delta15N across all seabird species, indicating biomagnification across trophic levels. The east side of Adak Island (a former military installation) was a likely point source of Sigma PCBs and p,p' DDE, particularly in glaucous-winged gulls. In contrast, elevated levels of these contaminants and Hg, along with PCB congener and chlorinated pesticide compositional patterns detected at Buldir Island indicated exposure from distant sources influenced by a combination of

  18. Sources of organochlorine contaminants and mercury in seabirds from the Aleutian archipelago of Alaska: Inferences from spatial and trophic variation

    USGS Publications Warehouse

    Ricca, Mark A.; Miles, A. Keith; Anthony, Robert G.

    2008-01-01

    Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an additional 8 seabird species representing different foraging and migratory guilds from Buldir Island to evaluate: 1) point source input from former military installations, 2) westward increases in contaminant concentrations suggestive of distant source input, and 3) effects of trophic status (δ15N) and carbon source (δ13C) on contaminant accumulation. Concentrations of Σ polychlorinated biphenyls (PCBs) and most chlorinated pesticides in glaucous-winged gulls consistently exhibited a ‘U’-shaped pattern of high levels at Buldir and the east side of Adak and low levels at Kiska and Amchitka. In contrast, concentrations of Σ PCBs and chlorinated pesticides in northern fulmars and tufted puffins did not differ among islands. Hg concentrations increased westward in glaucous-winged gulls and were highest in northern fulmars from Buldir. Among species collected only at Buldir, Hg was notably elevated in pelagic cormorants, and relatively high Σ PCBs were detected in black-legged kittiwakes. Concentrations of Σ PCBs, dichlorodiphenyldichloroethylene (p,p′ DDE), and Hg were positively correlated with δ15N across all seabird species, indicating biomagnification across trophic levels. The east side of Adak Island (a former military installation) was a likely point source of Σ PCBs and p,p′ DDE, particularly in glaucous-winged gulls. In contrast, elevated levels of these contaminants and Hg, along with PCB congener and chlorinated pesticide compositional patterns detected at Buldir Island indicated exposure from distant sources influenced by a combination of atmospheric

  19. How hype and glory gull

    SciTech Connect

    Pinsdorf, M.K. )

    1992-01-01

    Hyped expectations and lulling news, or no news translated as good news, are prescriptions for disasters. Such lulling encourages men to push themselves or their machines on missions impossible. It discourages constant vigilance or the plain speaking on which sound decisions must be made. Postdisaster, lulling intensifies the shock. When psychologically unprepared, victims are devastated more than necessary. This thesis will be illustrated by the historical example of Captain Robert F. Scott's 1910-1911 race to the South Pole against Roald Amundsen, the 1985 Challenger explosion, the 1986 Chernobyl nuclear accident, and the 1989 Exxon Valdez spill. Understanding the perils of treating such dangerous missions as milk runs will help managers avoid complacency, even accidents.

  20. 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

  1. Research, Monitoring, and Evaluation of Avian Predation on Salmonid Smolts in the Lower and Mid-Columbia River, 2006 Final Season Summary.

    SciTech Connect

    Roby, Daniel D.; Collis, Ken; Lyons, Donald E.

    2009-06-18

    This study investigates predation by piscivorous waterbirds on juvenile salmonids (Oncorhynchus spp.) from throughout the Columbia River Basin. During 2006, study objectives in the Columbia River estuary, work funded by the Bonneville Power Administration, were to (1) monitor and evaluate previous management initiatives to reduce Caspian tern (Hydroprogne caspia) predation on juvenile salmonids (smolts); (2) measure the impact of double-crested cormorant (Phalacrocorax auritus) predation on smolt survival, and assess potential management options to reduce cormorant predation; and (3) monitor large colonies of other piscivorous waterbirds in the estuary (i.e., glaucous-winged/western gulls [Larus glaucescens/occidentalis]) to determine the potential impacts on smolt survival. Study objectives on the mid-Columbia River, work funded by the Walla Walla District of the U.S. Army Corps of Engineers, were to (1) measure the impact of predation by Caspian terns and double-crested cormorants on smolt survival; and (2) monitor large nesting colonies of other piscivorous waterbirds (i.e., California gulls [L. californicus], ring-billed gulls [L. delawarensis], American white pelicans [Pelecanus erythrorhynchos]) on the mid-Columbia River to determine the potential for significant impacts on smolt survival. Our efforts to evaluate system-wide losses of juvenile salmonids to avian predation indicated that Caspian terns and double-crested cormorants were responsible for the vast majority of smolt losses to avian predators in the Columbia Basin, with most losses occurring in the Columbia River estuary. In 2006, East Sand Island in the Columbia River estuary supported the largest known breeding colonies of Caspian terns and double-crested cormorants in the world. The Caspian tern colony on East Sand Island consisted of about 9,200 breeding pairs in 2006, up slightly (but not significantly so) from the estimate of colony size in 2005 (8,820 pairs). There has not been a

  2. [Epidemiological studies on salmonella in a particular area ("Walcheren Project"). III. The incidence of salmonella in man, insects, gulls as well as foods scrapings from butcher's blocks, effluents of sewage treatment plants and drains from butcher's shops (author's transl)].

    PubMed

    Edel, W; Van Schothorst, M; Van Leusden, F M; Kampelmacher, E H

    1977-03-15

    In continuation of previous studies, various materials (meat and meat products, insects, gull droppings, scrapings from butcher's blocks, effluents of sewage treatment plants, drains from butcher's shops and faeces of patients) were examined again at the same time for the presence of Salmonella in a relatively small are (Walcheren) over a period of three months. As was also the case in previous studies, S. typhi murium (27.5 per cent), S. panama (22.2 per cent) and S. brandenburg (9.2 per cent) were the three serotypes most frequently isolated. The three most frequently isolated phage types of S. typhi murium were II 505 (62.1 per cent), II 502 (5.3 per cent) and I 650 (4.2 per cent). The serotypes and phage types were present in nearly all the materials studied which again emphasizes the fact that there are contamination cycles of Salmonella. These studies showed that the route of contamination divides in the butcher's shop. Salmonella ogranisms carried with the meat frome the slaughter-house find their way into the drains on the one hand, and, by meat and meat products, to consumers on the other. Moreover, the high degree of contamination of effluents is not in accordance with the small number of cases of salmonellosis.

  3. 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.

  4. 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.

  5. A stable isotope ( δ13C, δ15N) model for the North Water food web: implications for evaluating trophodynamics and the flow of energy and contaminants

    NASA Astrophysics Data System (ADS)

    Hobson, Keith A.; Fisk, Aaron; Karnovsky, Nina; Holst, Meike; Gagnon, Jean-Marc; Fortier, Martin

    The North Water Polynya is an area of high biological activity that supports large numbers of higher trophic-level organisms such as seabirds and marine mammals. An overall objective of the Upper Trophic-Level Group of the International North Water Polynya Study (NOW) was to evaluate carbon and contaminant flux through these high trophic-level (TL) consumers. Crucial to an evaluation of the role of such consumers, however, was the establishment of primary trophic linkages within the North Water food web. We used δ15N values of food web components from particulate organic matter (POM) through polar bears ( Ursus maritimus) to create a trophic-level model based on the assumptions that Calanus hyperboreus occupies TL 2.0 and there is a 2.4‰ trophic enrichment in 15N between birds and their diets, and a 3.8‰ trophic enrichment for all other components. This model placed the planktivorous dovekie ( Alle alle) at TL 3.3, ringed seal ( Phoca hispida) at TL 4.5, and polar bear at TL 5.5. The copepods C. hyperboreus, Chiridius glacialis and Euchaeta glacialis formed a trophic continuum (TL 2.0-3.0) from primary herbivore through omnivore to primary carnivore. Invertebrates were generally sorted according to planktonic, benthic and epibenthic feeding groups. Seabirds formed three trophic groups, with dovekie occupying the lowest, black-legged kittiwake ( Rissa tridactyla), northern fulmar ( Fulmarus glacialis), thick-billed murre ( Uria aalge), and ivory gull ( Pagophilia eburnea) intermediate (TL 3.9-4.0), and glaucous gull ( Larus hyperboreus) the highest (TL 4.6) trophic positions. Among marine mammals, walrus ( Odobenus rosmarus) occupied the lowest (TL 3.2) and bearded seal ( Erignathus barbatus), ringed seal, beluga whale ( Delphinapterus leucas), and narwhal ( Monodon monoceros) intermediate positions (TL 4.1-4.6). In addition to arctic cod ( Boreogadus saida), we suggest that lower trophic-level prey, in particular the amphipod Themisto libellula, contribute

  6. Environmental Assessment for the Management Options for Branch Memorial Park and Pond, Edwards Air Force Base, California

    DTIC Science & Technology

    2008-09-01

    sparsely vegetated ground at alkaline or saline lakes, reservoirs, and ponds; on riverine sand bars; and at sewage, salt-evaporation, and...evaporation ponds with the inland population regularly wintering at agricultural wastewater ponds in the San Joaquin Valley and at desert saline ...Eagle Aquila chrysaetos DFG: FP DFG: WL USFWS: BCC Black Tern Chlidonias niger DFG: SSC California Gull Larus californicus DFG: WL Double

  7. 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.

  8. 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, J.Y.; Golightly, R.T.; Ackerman, J.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

  9. 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.

  10. Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish.

    PubMed

    Letcher, Robert J; Bustnes, Jan Ove; Dietz, Rune; Jenssen, Bjørn M; Jørgensen, Even H; Sonne, Christian; Verreault, Jonathan; Vijayan, Mathilakath M; Gabrielsen, Geir W

    2010-07-01

    Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely

  11. Huna Tlingit Traditional Gull Egg Use Act

    THOMAS, 113th Congress

    Sen. Murkowski, Lisa [R-AK

    2013-01-28

    06/27/2013 Placed on Senate Legislative Calendar under General Orders. Calendar No. 105. (All Actions) Notes: For further action, see H.R.3110, which became Public Law 113-142 on 7/25/2014. Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  12. 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

  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. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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.

  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. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Plastic ingestion in marine-associated bird species from the eastern North Pacific.

    PubMed

    Avery-Gomm, S; Provencher, J F; Morgan, K H; Bertram, D F

    2013-07-15

    In addition to monitoring trends in plastic pollution, multi-species surveys are needed to fully understand the pervasiveness of plastic ingestion. We examined the stomach contents of 20 bird species collected from the coastal waters of the eastern North Pacific, a region known to have high levels of plastic pollution. We observed no evidence of plastic ingestion in Rhinoceros Auklet, Marbled Murrelet, Ancient Murrelet or Pigeon Guillemot, and low levels in Common Murre (2.7% incidence rate). Small sample sizes limit our ability to draw conclusions about population level trends for the remaining fifteen species, though evidence of plastic ingestion was found in Glaucous-Winged Gull and Sooty Shearwater. Documenting levels of plastic ingestion in a wide array of species is necessary to gain a comprehensive understanding about the impacts of plastic pollution. We propose that those working with bird carcasses follow standard protocols to assess the levels of plastic ingestion whenever possible.

  9. Huna Tlingit Traditional Gull Egg Use Act of 2011

    THOMAS, 112th Congress

    Sen. Murkowski, Lisa [R-AK

    2011-05-25

    07/28/2011 Committee on Energy and Natural Resources Subcommittee on National Parks. Hearings held. With printed Hearing: S.Hrg. 112-214. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  10. Parathion causes secondary poisoning in a laughing gull breeding colony

    USGS Publications Warehouse

    White, D.H.; King, K.A.; Mitchell, C.A.; Hill, E.F.; Lamont, T.G.

    1979-01-01

    Use of organophosphate insecticides as replacements for the more persistent organochlorine compounds has increased dramatically in recent years. Organophosphates are desirable for field application because they break down rapidly in the environment and do not persist in animal tissues (Stickel 1974). Nevertheless, certain organophosphates are extremely toxic to wildlife for short periods after application and have caused widespread mortality among exposed animals (Mills 1973, Stickel 1974, 1975, Mendelssohn 1977, and Zinkl et al. 1978).

  11. The importance of tidewater glaciers for marine mammals and seabirds in Svalbard, Norway

    NASA Astrophysics Data System (ADS)

    Lydersen, Christian; Assmy, Philipp; Falk-Petersen, Stig; Kohler, Jack; Kovacs, Kit M.; Reigstad, Marit; Steen, Harald; Strøm, Hallvard; Sundfjord, Arild; Varpe, Øystein; Walczowski, Waldek; Weslawski, Jan Marcin; Zajaczkowski, Marek

    2014-01-01

    Approximately 60% of Svalbard's land areas are glaciated at the present time. The Archipelago has more than 1100 glaciers (> 1 km2) and 163 of these are “tidewater glaciers” - that is glaciers that terminate (with their calving front) at the sea. It has been known for a long time that these glacier front areas are important feeding areas for seabirds and marine mammals. Herein, we review current knowledge regarding the importance of these areas for these animals and reflect upon the processes that create these apparent “hotspots”. Kittiwakes Rissa tridactyla, routinely dominate avian assemblages in front of glaciers in Svalbard, but fulmars Fulmarus glacialis, ivory gulls Pagophila eburnea and glaucous gulls Larus hyperboreus also contribute to aggregations, which can sometimes comprise many thousands of individuals. The birds are often found in the so-called “brown zone”, which is an area in front of tidewater glaciers that is ice-free due to currents and muddy due to suspended sediments. Animals at these sites typically have their stomachs full of large zooplankton or fish. These brown zones are also foraging hotspots for Svalbard's ringed seals (Pusa hispida) and white whales (Delphinapterus leucas). Prime breeding habitat for ringed seals in Svalbard occurs deep in the fjords where ice pieces calved from the glacier fronts become frozen into land-fast sea-ice, promoting the accumulation of snow to a depth suitable for ringed seal females to dig out birth lairs above breathing holes in the ice. These pupping areas are important hunting areas for polar bears (Ursus maritimus) in spring, especially female bears with cubs of the year during the period following emergence from the winter/birthing den. Glacier-ice pieces floating in coastal areas are also important for all seal species in the region as dry platforms during moulting and also as general resting platforms for both birds and seals. During the last decade there have been several years with a

  12. Effects of acute exposure to heavy fuel oil from the Prestige spill on a seabird.

    PubMed

    Alonso-Alvarez, Carlos; Pérez, Cristobal; Velando, Alberto

    2007-08-15

    Large quantities of petroleum products are released into the marine environment as result of tanker wrecks. Such catastrophic events have a dramatic impact on marine ecosystems, affecting a broad range of species. Seabirds are placed at the uppermost trophic level of the marine food chain. Therefore, important toxic effects are expected in these organisms. The recent Prestige oil spill gave the opportunity to test this. A previous study reported that yellow-legged gulls (Larus michahellis) breeding in the oiled area (17 months after the spill) showed differences both in plasma biochemistry and in the total circulating levels of polycyclic aromatic hydrocarbons (TPAHs) in blood regard to gulls sampled in clean areas. In the present study, wild yellow-legged gulls were fed with heavy fuel oil from the Prestige oil spill (P-gulls) and compared with control gulls (C-gulls) fed only with the vehicle (vegetable oil). Consistent with the cited previous findings, gulls fed with fuel oil showed reduced glucose and inorganic phosphorus levels in plasma, as well as a trend to significantly reduced creatinine values. In addition, glucose concentration was negatively related to TPAH levels. Males but not females fed with fuel oil showed higher plasma activity of asparatate aminotransferase (AST) than controls. With regard to plasma activity of gamma-glutamyl transferase (GGT), the results were opposite to the previous study. The GGT activity increased in C-females, apparently to meet with increased liver metabolism due to egg laying demands, but not in P-females. Differences to the previous study possibly reflect different adaptive responses of these enzymes to an acute short-term exposure to heavy fuel oil. Since the yellow-legged gull belongs to a complex of species widely distributed throughout the Northern hemisphere, the results as a whole might provide a tool for future evaluations of short- and long-term effects of oil spills on seabirds. Decreased glucose and inorganic

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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

  5. Riding the crimson tide: mobile terrestrial consumers track phenological variation in spawning of an anadromous fish.

    PubMed

    Schindler, Daniel E; Armstrong, Jonathan B; Bentley, Kale T; Jankowski, Kathijo; Lisi, Peter J; Payne, Laura X

    2013-06-23

    When resources are spatially and temporally variable, consumers can increase their foraging success by moving to track ephemeral feeding opportunities as these shift across the landscape; the best examples derive from herbivore-plant systems, where grazers migrate to capitalize on the seasonal waves of vegetation growth. We evaluated whether analogous processes occur in watersheds supporting spawning sockeye salmon (Oncorhynchus nerka), asking whether seasonal activities of predators and scavengers shift spatial distributions to capitalize on asynchronous spawning among populations of salmon. Both glaucous-winged gulls and coastal brown bears showed distinct shifts in their spatial distributions over the course of the summer, reflecting the shifting distribution of spawning sockeye salmon, which was associated with variation in water temperature among spawning sites. By tracking the spatial and temporal variation in the phenology of their principal prey, consumers substantially extended their foraging opportunity on a superabundant, yet locally ephemeral, resource. Ecosystem-based fishery management efforts that seek to balance trade-offs between fisheries and ecosystem processes supported by salmon should, therefore, assess the importance of life-history variation, particularly in phenological traits, for maintaining important ecosystem functions, such as providing marine-derived resources for terrestrial predators and scavengers.

  6. Riding the crimson tide: mobile terrestrial consumers track phenological variation in spawning of an anadromous fish

    PubMed Central

    Schindler, Daniel E.; Armstrong, Jonathan B.; Bentley, Kale T.; Jankowski, KathiJo; Lisi, Peter J.; Payne, Laura X.

    2013-01-01

    When resources are spatially and temporally variable, consumers can increase their foraging success by moving to track ephemeral feeding opportunities as these shift across the landscape; the best examples derive from herbivore–plant systems, where grazers migrate to capitalize on the seasonal waves of vegetation growth. We evaluated whether analogous processes occur in watersheds supporting spawning sockeye salmon (Oncorhynchus nerka), asking whether seasonal activities of predators and scavengers shift spatial distributions to capitalize on asynchronous spawning among populations of salmon. Both glaucous-winged gulls and coastal brown bears showed distinct shifts in their spatial distributions over the course of the summer, reflecting the shifting distribution of spawning sockeye salmon, which was associated with variation in water temperature among spawning sites. By tracking the spatial and temporal variation in the phenology of their principal prey, consumers substantially extended their foraging opportunity on a superabundant, yet locally ephemeral, resource. Ecosystem-based fishery management efforts that seek to balance trade-offs between fisheries and ecosystem processes supported by salmon should, therefore, assess the importance of life-history variation, particularly in phenological traits, for maintaining important ecosystem functions, such as providing marine-derived resources for terrestrial predators and scavengers. PMID:23554279

  7. Mitigation of bird collisions with transmission lines: Final report

    SciTech Connect

    Beaulaurier, D.L.

    1981-09-11

    In this study removal of overhead groundwires was evaluated as a technique for mitigating bird collisions with transmission lines. Groundwires were removed by BPA from a 500 kV double circuit line at Bybee Lake in Portland, Oregon. Earlier studies at these sites had documented small but measurable collision rates (i.e., No. collisions/No. flights) attributed primarily to collisions with groundwires. Observations of bird flights and searches for dead birds in the vicinity of the lines constituted the primary methods of data collection during pre- and post-removal studies. Field work was conducted from October 1980 through March 1981. A total of seven dead birds and eight feather spots were found after groundwire removal. Species found were green-winged teal, pintail, greater scaup, American wigeon, glaucous-winged gull, starling, red-winged blackbird and song sparrow. No collisions with transmission lines were observed. During pre-removal studies at these two sites, a total of 53 dead birds and 22 feather spots were found over two years of study. It was necessary to document flight intensity (No. flights/day) during pre- and post-removal studies, in order to determine if the number of dead birds found changed because of groundwire removal or simply because of changes in flight intensity. 41 refs., 18 figs., 22 tabs.

  8. A two-dimensional HPLC separation for the enantioselective determination of hexabromocyclododecane (HBCD) isomers in biota samples.

    PubMed

    Bester, Kai; Vorkamp, Katrin

    2013-08-01

    A new method for enantioselective analysis of isomers of hexabromocyclododecane (HBCD) is described, using a two-dimensional high-performance liquid chromatography (HPLC) approach to avoid coelution, in particular between (+) α-HBCD, (+) β-HBCD, or (+) γ-HBCD. After isomer separation on a conventional column, the single isomers are transferred to an enantioselective HPLC column using heart cuts. Two enantioseparations are conducted in two separate partial chromatograms: one for α-HBCD and one for β- and γ-HBCD. The result is a completely undisturbed enantioselective separation for α-HBCD at a resolution of 4.11. A peak capacity of 107 was achieved. This peak capacity is utilized by the six peaks of the three isomers with two enantiomers each by 6%. This method was applied to samples of sand eel oil, glaucous gull, and ringed seal. The calibration was performed by treating each enantiomer as a single analyte using a multilevel internal standard calibration. Enantiomeric fractions of 0.495-0.501 with standard deviations (SDs) of 0.056-0.071 were determined for racemic standards of α-HBCD, while the values for fish oil were 0.548-0.562 with SD of 0.018-0.041, depending on the respective mass spectrometric transition.

  9. Draft Genome Sequence of Catellicoccus marimammalium, a Novel Species Commonly Found in Gull Feces

    EPA Science Inventory

    Catellicoccus marimammalium is a relatively uncharacterized Gram-positive, facultative anaerobe with potential utility as an indicator of waterfowl fecal contamination. Here we report an annotated draft genome sequence that suggests this organism may be a symbiotic gut microbe.

  10. American Conference on Theoretical Chemistry Held in Gull Lake, Minnesota on July 25-31, 1987.

    DTIC Science & Technology

    1988-01-01

    Research Project. . h) Permanent address: Dept. de Quimica -Fisica, Facultad de CC. Quimicas , ," A Universidad Complutense, 28040 Madrid, SPAIN. c...Dept. de Quimica Fisica, Facultad de CC. Quimicas , Universidad Complutense, 28040 Madrid, SPAIN. c) Alfred P. Sloan Fellow...Palmieri, Dip. Chimilca Fisica e Inorganica, Universita’, Bologna(1) E. Garcia, Dep. de Quimica Fisica, Universidad del Pals Vasco, Bilbao(E) A. Lagana

  11. Sea gulls, butterflies, and grasshoppers: A brief history of the butterfly effect in nonlinear dynamics

    NASA Astrophysics Data System (ADS)

    Hilborn, Robert C.

    2004-04-01

    The butterfly effect has become a popular metaphor for sensitive dependence on initial conditions—the hallmark of chaotic behavior. I describe how, where, and when this term was conceived in the 1970s. Surprisingly, the butterfly metaphor was predated by more than 70 years by the grasshopper effect.

  12. Abundance, Distribution and Estimated Consumption (kg fish) of Piscivorous Birds Along the Yakima River, Washington State; Implications for Fisheries Management, 2002 Annual Report.

    SciTech Connect

    Major, III, Walter; Grassley, James M.; Ryding, Kristen E.

    2003-05-01

    abundance of fish-eating birds, primarily ring-billed (Larus delawarensis) and California (L. californicus) gulls and monitored their behavior at two man-made structures within the Yakima River in eastern Washington: Horn Rapids Dam, a low-head irrigation dam, and the return pipe for the Chandler Juvenile Fish Handling Facility. Earlier observations of congregations of gulls at these structures suggested an increased likelihood of predation of out-migrating juvenile salmonids. We estimated the number of fish consumed and examined the relationship between river flow and gull numbers and fish taken. Numbers of gulls at the structures varied daily between their arrival in Late March-early April and departure in late June (mean ({+-}SE) - Horn Rapids: 11.7 ({+-}2.0), Chandler: 20.1 ({+-}1.5) ). During the 4-yr study, numbers at Horn Rapids peaked dramatically during the last 2 weeks in May (between 132.9 ({+-}4.2) to 36.6 ({+-}2.2) gulls/day) and appeared to the associated with the release of > 1-mil hatchery juvenile fall chinook (Oncorhynchus tshawytscha) above the 2 study sites. A comparable peak in gull abundance was not observed at Chandler. Diurnal patterns of gull abundance also varied among years and sites. The relationship between foraging efficiency and gull numbers was not consistent among years or sites. Gull numbers were not correlated with river flow when year was considered. However, variations in flow among years appeared to be associated with average gull numbers at each site, but trends were not consistent between sites. Low seasonal flows were associated with increased predation at Chandler, whereas high seasonal flows were associated with increased predation at Horn Rapids. Assuming all fish taken were salmonids, we estimate gulls consumed between 0.1-10.3 % of the juvenile salmonids passing or being released from the Chandler Juvenile Fish Monitoring Facility located above the two structures. Staggered releases of hatchery fish, nocturnal releases of fish

  13. 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.

  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. 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.

  16. 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.

  17. Breeding productivity of Smith Island black ducks

    USGS Publications Warehouse

    Haramis, G.M.; Jorde, D.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

  18. 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

  19. 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

  20. 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

  1. 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

  2. '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.

  3. 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.

  4. 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.

  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. 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.

  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. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Polychlorinated biphenyls in two species of Arctic seabirds from the Svalbard Area

    SciTech Connect

    Daelemans, F.F.; Schepens, P.J.C.; Mehlum, F.

    1992-06-01

    Anthropogenic long-range pollution of the Arctic could lead to rapid environmental changes at a large geographical scale. Arctic ecosystems are regarded as very vulnerable since the energy flow is channeled through only one or a few essential links. The apparent stability and its survival over longer periods is probably due to the large spatial scale involved which provides the mending of regions of disturbance by repopulation from undisturbed areas. The large geographical scale of man-made pollution from the industrialized countries may interfere with this basic factor of stability in the Arctic ecosystem. Organochlorine compounds is one important group of pollutants transported through the atmosphere and ocean currents from the industrial areas to the Arctic. The ability of organochlorine compounds to enter the food chain in significant quantities, as a result of their relative high stability, lipid solubility and tendency for bioaccumulation, poses a possible hazard for the Arctic fauna. In this respect polychlorinated hydrocarbons and more in particular polychlorinated biphenyls (PCBs) seem to be one of the most dangerous pollutants of the Arctic environment. The archipelago of Svalbard in the European Arctic is an area with only minor local industrial activities, and the anthropogenic pollution recorded in the area is assumed to be mainly of foreign origin. In this paper we present data on PCB levels in two species of Arctic seabirds from the Svalbard area. One is the Glaucous Gull and the other the Black Guillemot. Concentrations of total PCB as well as those of 10 different congeners are given. Special attention is given to three of the most toxic non-orthochlorobiphenyls. 15 refs., 2 figs., 3 tabs.

  12. Interspecific and intraspecific variation in selenium:mercury molar ratios in saltwater fish from the Aleutians: potential protection on mercury toxicity by selenium.

    PubMed

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

    2012-08-01

    A number of factors affect the consumption risk from mercury in fish, including mercury levels, seasonal patterns of mercury concentrations, human consumption patterns, and sensitive populations (e.g. pregnant women, fetuses, young children, and yet unknown genetic factors). Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for saltwater fish. We examine levels of mercury and selenium in several species of fish and seabirds from the Aleutians (Alaska), determine selenium:mercury molar ratios, and examine species-specific and individual variation in the ratios as a means of exploring the use of the ratio in risk assessment and risk management. Variation among species was similar for mercury and selenium. There was significant interspecific and intraspecific variation in selenium:mercury molar ratios for fish, and for birds. The mean selenium:mercury molar ratios for all fish and bird species were above 1, meaning there was an excess of selenium relative to mercury. It has been suggested that an excess of selenium confers some protective advantage for salt water fish, although the degree of excess necessary is unclear. The selenium:mercury molar ratio was significantly correlated negatively with total length for most fish species, but not for dolly varden. Some individuals of Pacific cod, yellow irish lord, rock greenling, Pacific halibut, dolly varden, and to a lesser extent, flathead sole, had selenium:mercury ratios below 1. No bird muscle had an excess of mercury (ratio below 1), and only glaucous-winged gull and pigeon guillemot had ratios between 1 and 5. There was a great deal of variation in selenium:mercury molar ratios within fish species, and within bird species, making it difficult and impractical to use these ratios in risk assessment or management, for fish advisories, or for consumers, particularly given the difficulty of interpreting the ratios.

  13. Multi-laboratory evaluations of the performance of Catellicoccus marimammalium PCR assays developed to target gull fecal sources

    EPA Science Inventory

    Here we report results from a multi-laboratory (n=11) evaluation of four different PCR methods targeting the 16S rRNA gene of Catellicoccus marimammalium used to detect fecal contamination from birds in coastal environments. The methods included conventional end-point PCR, a SYBR...

  14. Cultural Resources Investigation of the Reservoir Shorelines: Gull Lake, Leech Lake, Pine River, and Lake Pokegama. Volume 1,

    DTIC Science & Technology

    1979-06-01

    Douglas Birk cites William Warren (1852), Lewis and Clark (1804-1806), Henry Schoolcraft (1820) and Nicholas King (1805-1807) to substantiate the loc...suggests this is the post indicated on Lewis’ and Clark’s map from the expedition in 1804-1806. (Birk, 1970: 2) Schoolcraft , in 1820, says there was an old...offshore. CM a -. >.dl aA Figure 27. Lithic artifacts from site CA 43. Top row ; left, triangular point: * center, bifacially flaked knife; right, side

  15. Virulent Newcastle disease viruses isolated from cormorant and gull species in the states of the Atlantic Flyway in 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Newcastle disease viruses (NDV) have been the causative agent for die-offs of juvenile double-crested cormorants (Phalacrocorax auritus) in the northern border-states focused around the Great Lakes of the U.S. in years past. However, the most recent die-off has included not only great cormorants (P...

  16. Characterization of Newcastle disease viruses isolated from cormorant and gull species in the United States in 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Newcastle disease virus (NDV), a member of the genus Avulavirus of the family Paramyxoviridae, is the causative agent of Newcastle disease (ND) a highly contagious disease that affects many species of birds and which frequently causes significant economic losses to the poultry industry worldwide. V...

  17. Leaf cuticular lipids on the Shandong and Yukon ecotypes of saltwater cress, eutrema salsugineum, and their response to water deficiency and impact on cuticle permeability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of water deficit stress on leaf cuticular waxes and cutin monomers, and traits associated with cuticle permeability, were examined in Shandong and Yukon ecotypes of Eutrema salsugineum (syn. Thellungiella salsuginea). Although Shandong exhibits glaucous leaves, and Yukon is non-glaucous, ...

  18. Cuticular Wax Accumulation Is Associated with Drought Tolerance in Wheat Near-Isogenic Lines

    PubMed Central

    Guo, Jun; Xu, Wen; Yu, Xiaocong; Shen, Hao; Li, Haosheng; Cheng, Dungong; Liu, Aifeng; Liu, Jianjun; Liu, Cheng; Zhao, Shijie; Song, Jianmin

    2016-01-01

    Previous studies have shown that wheat grain yield is seriously affected by drought stress, and leaf cuticular wax is reportedly associated with drought tolerance. However, most studies have focused on cuticular wax biosynthesis and model species. The effects of cuticular wax on wheat drought tolerance have rarely been studied. The aims of the current study were to study the effects of leaf cuticular wax on wheat grain yield under drought stress using the above-mentioned wheat NILs and to discuss the possible physiological mechanism of cuticular wax on high grain yield under drought stress. Compared to water-irrigated (WI) conditions, the cuticular wax content (CWC) in glaucous and non-glaucous NILs under drought-stress (DS) conditions both increased; mean increase values were 151.1 and 114.4%, respectively, which was corroborated by scanning electronic microscopy images of large wax particles loaded on the surfaces of flag leaves. The average yield of glaucous NILs was higher than that of non-glaucous NILs under DS conditions in 2014 and 2015; mean values were 7368.37 kg·ha−1 and 7103.51 kg·ha−1. This suggested that glaucous NILs were more drought-tolerant than non-glaucous NILs (P = 0.05), which was supported by the findings of drought tolerance indices TOL and SSI in both years, the relatively high water potential and relative water content, and the low ELWL. Furthermore, the photosynthesis rate (Pn) of glaucous and non-glaucous wheat NILs under DS conditions decreased by 7.5 and 9.8%, respectively; however, glaucous NILs still had higher mean values of Pn than those of non-glaucous NILs, which perhaps resulted in the higher yield of glaucous NILs. This could be explained by the fact that glaucous NILs had a smaller Fv/Fm reduction, a smaller PI reduction and a greater ABS/RC increase than non-glaucous NILs under DS conditions. This is the first report to show that wheat cuticular wax accumulation is associated with drought tolerance. Moreover, the leaf

  19. 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 humanuse 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 http://dx.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

  20. 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

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. [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.

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. Using seabird habitat modeling to inform marine spatial planning in central California's National Marine Sanctuaries.

    PubMed

    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 spatial

  4. 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

  5. Population trends of Alaskan seabirds

    USGS Publications Warehouse

    Hatch, Scott A.

    1993-01-01

    seems reasonably certain that real changes in some of the open-nesters like Common Murres (down at Forrester Island, up at St. Lazaria) and Glaucous-winged and Herring Gulls (absent or down at both sites) have occurred since Willet's time.

  6. [Proceedings of the 4th National Conference on Outdoor Education (Kellogg Gull Lake Biological Station, Michigan, October 22-24, 1970).

    ERIC Educational Resources Information Center

    Mawdsley, Jack K.; And Others

    Participants from 23 states and 4 Canadian provinces attended the Fourth National Conference on Outdoor Education sponsored by the Outdoor Education Project and the Council on Outdoor Education and Camping of the American Association for Health, Physical Education, and Recreation. The conference was primarily a working conference designed to deal…

  7. Education in and for the Outdoors. Report of the National Conference on Outdoor Education (Kellogg Gull Lake Biological Station, Hickory Corners, Michigan, May 2-4, 1962).

    ERIC Educational Resources Information Center

    American Association for Health, Physical Education, and Recreation, Washington, DC.

    The two board aspects of outdoor education considered in this document are education in the outdoors, using the natural environment as a laboratory for learning, and education for the outdoors, with a focus on teaching skills and appreciations for outdoor recreation. Conference procedures, keynote addresses, current practices, contributions to…

  8. Detection limits and cost comparisons of human- and gull-associated conventional and quantitative PCR assays in artificial and environmental waters

    EPA Science Inventory

    Modern techniques for tracking fecal pollution in environmental waters require investing in DNA-based methods to determine the presence of specific fecal sources. To help water quality managers decide whether to employ routine polymerase chain reaction (PCR) or quantitative PC...

  9. Cultural Resources Survey of the Nisswa Lakes, A Part of the Gull Lake Reservoir in Cass and Crow Wing Counties, Minnesota.

    DTIC Science & Technology

    1985-10-20

    quartzite debitage ST260 5-15 1-pc. orange quartz debitage ST262 5-15 1-pc. basalt debitage 1-FCR ST265 5-20 2-FCR Site: 21CA-Find Spot 8 Field Number: #83-8...quartz debitage 1-red quartzite flake 1- basalt flake 1-pc.calcined bone Site: 21CA146 Field Number/Name: #84-14 (Spider Ridge Point Site) jyR9_gSAt...Mound 1 Collections: Hemline University H79 Materials/Source: Surface Collection:l- basalt flake ST672 9-32cm 1-GT ceramic "crumb" 1-white quartz

  10. Does plant colour matter? Wax accumulation as an indicator of decline in Juniperus thurifera.

    PubMed

    Esteban, R; Fernández-Marín, B; Olano, J M; Becerril, J M; García-Plazaola, J I

    2014-03-01

    The photosynthesis in evergreen trees living in Mediterranean ecosystems is subjected to multiple climatic stresses due to water shortage and high temperatures during the summer and to low temperatures during the winter. Mediterranean perennials deploy different photoprotective mechanisms to prevent damage to the photosynthetic system. Wax accumulation in leaves is a primary response which by enhancing light scattering in the leaf surface reduces incident radiation in the mesophyll. The existence of high variability in wax accumulation levels between coexisting individuals of a species has a visual effect on colour that provides distinguishable green and glaucous phenotypes. We explored this variability in a Mediterranean evergreen tree Juniperus thurifera (L.) to evaluate the impact of epicuticular wax on optical and ecophysiological properties and on the abundance of photoprotective pigments throughout an annual cycle. Because of light attenuation by waxes, we expected that glaucous phenotypes would lower the need for photoprotective pigments. We evaluated the effect of phenotype and season on reflectance, defoliation levels, photochemical efficiency and photoprotective pigment contents in 20 green and 20 glaucous junipers. Contrary to our expectations, the results showed that glaucous trees suffered from a diminution in photochemical efficiency, but there was no reduction in photoprotective pigments. Differences between glaucous and green phenotypes were greater in winter, which is the most stressful season for this species. Glaucous individuals also showed the highest levels of leaf defoliation. The lower photochemical efficiency of glaucous trees, together with higher defoliation rates and equal or greater number of physiological photoprotective mechanisms, suggests that in spite of wax accumulation, glaucous trees suffer from more severe stress than green ones. This result suggests that changes in colouration in Mediterranean evergreens may be a decline

  11. Isolation of Candida albicans and halophilic Vibrio spp. from aquatic birds in Connecticut and Florida.

    PubMed Central

    Buck, J D

    1990-01-01

    Halophilic vibrios were recovered from feces of six types of aquatic birds (gulls, pelicans, Canada geese, swans, egrets, cormorants) from Connecticut and/or Florida shorelines. Candida albicans was isolated from gulls and Canada geese in Connecticut and from gulls and cormorants in Florida. PMID:2180374

  12. Mass and energy transfer to seabirds in the southeastern Bering Sea

    NASA Astrophysics Data System (ADS)

    Schneider, David C.; Hunt, George L.; Harrison, Nancy M.

    It has been hypothesized that differentiation in food web structure occurs across the Bering Sea continental shelf as a result of seasonal differentiation of water masses. We tested this idea using an apex predator, pelagic birds. Seasonal abundance of birds in central Bristol Bay was estimated from counts made while underway between hydrographic stations. Prey and body mass were determined from birds collected at sea. Daily intake was estimated as an allometric function of body mass. Annual occupancy was estimated as the integral of a normal curve fit to seasonal data. Estimated carbon flux to seabirds in the middle domain was 0.12 gC m -2 y -1 in 1980, 0.18 gC m -2 y -1 in 1981. Carbon flux to seabirds in the adjacent waters of the outer shelf domain was 1.8 times higher than in the middle domain in 1980, 1.6 times higher in 1981. Carbon flux to seabirds in the inner domain was 1.2 times higher than in the middle domain in 1980, and 3.3 times higher in 1981. Carbon flux to seabirds in the outer domain was due primarily to non-diving species, principally northern fulmars ( Fulmarus glacialis) during the summer and autumn, and Larus gulls in the autumn and winter. Flux to seabirds in the inner domain was due to diving birds, principally murres ( Uria sp.) in the spring and shearwaters ( Puffinus sp.) during the summer. The euphausiid Thysanoessa raschii was the primary food source of shearwaters in shallow waters of the inner shelf domain. A more diverse set of prey, including squid, jellyfish, hyperiids, and fish, was taken by shearwaters and fulmars in the deeper waters of the outer and middle shelf domains. This result suggests that prey diversity is higher in seasonally stratified waters of outer Bristol Bay than in mixed waters of inner Bristol Bay. Greater energy flux to diving species in shallow water, and greater energy flux to non-divers in deep water may be a function of topographic control of prey patchiness.

  13. Top-down and bottom-up factors affecting seabird population trends in the California current system (1985-2006)

    NASA Astrophysics Data System (ADS)

    Ainley, David G.; David Hyrenbach, K.

    2010-03-01

    To characterize the environmental factors affecting seabird population trends in the central portion of the California current system (CCS), we analyzed standardized vessel-based surveys collected during the late spring (May-June) upwelling season over 22 yr (1985-2006). We tested the working hypothesis that population trends are related to species-specific foraging ecology, and predicted that temporal variation in population size should be most extreme in diving species with higher energy expenditure during foraging. We related variation in individual species abundance (number km -2) to seasonally lagged (late winter, early spring, late spring) and concurrent ocean conditions, and to long-term trends (using a proxy variable: year) during a multi-decadal period of major fluctuations in the El Niño-Southern oscillation (ENSO) and the Pacific decadal oscillation (PDO). We considered both remote (Multivariate ENSO Index, PDO) and local (coastal upwelling indices and sea-surface temperature) environmental variables as proxies for ocean productivity and prey availability. We also related seabird trends to those of potentially major trophic competitors, humpback ( Megaptera novaeangliae) and blue ( Balaenoptera musculus) whales, which increased in number 4-5-fold midway during our study. Cyclical oscillations in seabird abundance were apparent in the black-footed albatross ( Phoebastria nigripes), and decreasing trends were documented for ashy storm-petrel ( Oceanodroma homochroa), pigeon guillemot ( Cepphus columbus), rhinoceros auklet ( Cerorhinca monocerata), Cassin’s auklet ( Ptychoramphus aleuticus), and western gull ( Larus occidentalis); the sooty shearwater ( Puffinus griseus), exhibited a marked decline before signs of recovery at the end of the study period. The abundance of nine other focal species varied with ocean conditions, but without decadal or long-term trends. Six of these species have the largest global populations in the CCS, and four are highly

  14. 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

  15. 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.

  16. 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

  17. Biogeochemical Indicators in High- and Low-Arctic Marine and Terrestrial Avian Community Changes: Comparative Isotopic (13C, 15N, and 34S) Studies in Alaska and Greenland

    NASA Astrophysics Data System (ADS)

    Causey, D.; Bargmann, N. A.; Burnham, K. K.; Burnham, J. L.; Padula, V. M.; Johnson, J. A.; Welker, J. M.

    2011-12-01

    Understanding the complex dynamics of environmental change in northern latitudes is of paramount importance today, given documented rapid shifts in sea ice, plant phenology, temperatures, deglaciation, and habitat fidelity. This knowledge is particularly critical for Arctic avian communities, which are integral components by which biological teleconnections are maintained between the mid and northern latitudes. Furthermore, Arctic birds are fundamental to Native subsistence lifestyles and a focus for conservation activities. Avian communities of marine and terrestrial Arctic environments represent a broad spectrum of trophic levels, from herbivores (eg., geese Chen spp.), planktivores (eg., auklets Aethia spp.), and insectivores (eg., passerines: Wheatears Oenanthe spp., Longspurs Calcarius spp.), to predators of marine invertebrates (eg., eiders Somateria spp.), nearshore and offshore fish (eg., cormorants Phalacrocorax spp, puffins Fratercula spp.), even other bird species (eg., gulls Larus spp., falcons Peregrinus spp.). This diversity of trophic interconnections is an integral factor in the dynamics of Arctic ecosystem ecology, and they are key indicators for the strength and trajectories of change. We are especially interested in their feeding ecology, using stable isotope-diet relations to examine historical diets and to predict future feeding ecology by this range of species. Since 2009, we have been studying the foodweb ecology using stable isotopes (δ13C, δ15N, δ34S) of contemporaneous coastal and marine bird communities in High Arctic (Northwest Greenland) and Low Arctic (western Aleutian Islands, AK). We are quantifying the isotopic values of blood, organ tissues, and feathers, and have carried out comparisons between native and lipid-extracted samples. Although geographically distant, these communities comprise similar taxonomic and ecological congeners, including several species common to both (eg., Common Eider, Black-legged Kittiwake, Northern

  18. EROD activity and stable isotopes in seabirds to disentangle marine food web contamination after the Prestige oil spill.

    PubMed

    Velando, Alberto; Munilla, Ignacio; López-Alonso, Marta; Freire, Juan; Pérez, Cristobal

    2010-05-01

    In this study, we measured via surgical sampling hepatic EROD activity in yellow-legged gulls from oiled and unoiled colonies, 17 months after the Prestige oil spill. We also analyzed stable isotope composition in feathers of the biopsied gulls, in an attempt to monitor oil incorporation into marine food web. We found that yellow-legged gulls in oiled colonies were being exposed to remnant oil as shown by hepatic EROD activity levels. EROD activity was related to feeding habits of individual gulls with apparent consequences on delayed lethality. Capture-recapture analysis of biopsied gulls suggests that the surgery technique did not affect gull survival, giving support to this technique as a monitoring tool for oil exposure assessment. Our study highlights the combination of different veterinary, toxicological and ecological methodologies as a useful approach for the monitoring of exposure to remnant oil after a large oil spill.

  19. 36 CFR 293.16 - Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National Forest...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Lake, Alder Lake, Canoe Lake, Sea Gull Lake, and Island River east of Lake Isabella, all in Lake County, except that motorboats may not operate— (i) After January 1, 1999 on that portion of Sea Gull Lake west..., motorized vehicle not exceeding forty inches in width designed to operate on ice and snow, having a ski...

  20. 36 CFR 293.16 - Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National Forest...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Lake, Alder Lake, Canoe Lake, Sea Gull Lake, and Island River east of Lake Isabella, all in Lake County, except that motorboats may not operate— (i) After January 1, 1999 on that portion of Sea Gull Lake west..., motorized vehicle not exceeding forty inches in width designed to operate on ice and snow, having a ski...

  1. 36 CFR 293.16 - Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National Forest...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Lake, Alder Lake, Canoe Lake, Sea Gull Lake, and Island River east of Lake Isabella, all in Lake County, except that motorboats may not operate— (i) After January 1, 1999 on that portion of Sea Gull Lake west..., motorized vehicle not exceeding forty inches in width designed to operate on ice and snow, having a ski...

  2. Coastal Inlets as Strategic Habitat for Shorebirds in the Southeastern United States

    DTIC Science & Technology

    2008-10-01

    variety of coastal birdlife, including pelicans, cormorants , gulls, terns, and “shorebirds.” Shorebirds in the United States are roughly 50 species of...of southeastern U.S. coastal birds, including various species of gulls, terns, cormorants , and Brown Pelicans. ACKNOWLEDGEMENTS: Data evaluated

  3. The distribution of seabirds and pinnipeds in Marguerite Bay and their relationship to physical features during austral winter 2001

    USGS Publications Warehouse

    Chapman, Erik W.; Ribic, C.A.; Fraser, William R.

    2004-01-01

    The distribution of seabirds and pinnipeds and their relationship to physical oceanographic variables were investigated as part of the US Southern Ocean Global Ocean Ecosystem Dynamics field program along a study grid centered around Marguerite Bay on the west Antarctic Peninsula during late fall (April-May) and winter (July-August), 2001. Sea-ice conditions during the cruises provided an opportunity to compare the relationship among physical oceanographic variables and species distributions before and after the development of pack ice. During the fall cruise before pack ice development, both sea-ice-affiliated species and open-water-affiliated were observed in the area. The most common ice-affiliated species observed at this time were snow petrel (Pagodroma nivea, 0.7 individuals km-2) and Antarctic petrel (Thalassoica antarctica, 0.2 individuals km-2) and the most common open-water-affiliated species were blue petrel (Halobaena caerulea, 0.4 individuals km-2), cape petrel (Daption capense, 0.2 individuals km-2), and southern fulmar (Fulmarus glacialoides, 0.1 individuals km-2). In addition, Antarctic fur seals (Arctocephalus gazella, 0.1 individuals km-2) and crabeater seals (Lobodon carcinophagus, 0.4 individuals km-2) were observed in low numbers. Akaike's information criterion was used to assess competing models that predicted predator distributions based on physical oceanographic variables proposed to structure predator distribution in previous research. These analyses indicated that predator distributions were primarily associated with water-mass structure and variability in bottom depth during the fall cruise. Crabeater seal, snow petrel, Antarctic petrel, and southern fulmar had higher densities in Inner Shelf Water, particularly near Alexander Island where a coastal current was present. Blue petrel, kelp gull (Larus dominicanus), and southern giant petrel (Macronectes giganteus) were positively associated with variability in bottom depth in April

  4. The distribution of seabirds and pinnipeds in Marguerite Bay and their relationship to physical features during austral winter 2001

    NASA Astrophysics Data System (ADS)

    Chapman, Erik W.; Ribic, Christine A.; Fraser, William R.

    2004-08-01

    The distribution of seabirds and pinnipeds and their relationship to physical oceanographic variables were investigated as part of the US Southern Ocean Global Ocean Ecosystem Dynamics field program along a study grid centered around Marguerite Bay on the west Antarctic Peninsula during late fall (April-May) and winter (July-August), 2001. Sea-ice conditions during the cruises provided an opportunity to compare the relationship among physical oceanographic variables and species distributions before and after the development of pack ice. During the fall cruise before pack ice development, both sea-ice-affiliated species and open-water-affiliated were observed in the area. The most common ice-affiliated species observed at this time were snow petrel ( Pagodroma nivea, 0.7 individuals km -2) and Antarctic petrel ( Thalassoica antarctica, 0.2 individuals km -2) and the most common open-water-affiliated species were blue petrel ( Halobaena caerulea, 0.4 individuals km -2), cape petrel ( Daption capense, 0.2 individuals km -2), and southern fulmar ( Fulmarus glacialoides, 0.1 individuals km -2). In addition, Antarctic fur seals ( Arctocephalus gazella, 0.1 individuals km -2) and crabeater seals ( Lobodon carcinophagus, 0.4 individuals km -2) were observed in low numbers. Akaike's information criterion was used to assess competing models that predicted predator distributions based on physical oceanographic variables proposed to structure predator distribution in previous research. These analyses indicated that predator distributions were primarily associated with water-mass structure and variability in bottom depth during the fall cruise. Crabeater seal, snow petrel, Antarctic petrel, and southern fulmar had higher densities in Inner Shelf Water, particularly near Alexander Island where a coastal current was present. Blue petrel, kelp gull ( Larus dominicanus), and southern giant petrel ( Macronectes giganteus) were positively associated with variability in bottom depth

  5. Birds of the Kilbuck and Ahklun mountain region, Alaska

    USGS Publications Warehouse

    Petersen, Margaret R.; Weir, Douglas N.; Dick, Matthew H.

    1991-01-01

    also provide further information on distributions or documentation of unusual occurrences for nine taxa (frigatebird, Fregata spp.; Baikal teal, Anas formosa; American kestrel, Falco sparverius; Terek sandpiper, Xenus cinereus; bristle-thighed curlew, Numenius tahitiensis; slaty-backed gull, Larus schistisagus; rufous hummingbird, Selasphorus rufus; song sparrow, Melospiza melodia; and red-winged blackbird, Agelaius phoeniceus). We provide quantitative data on the coastal migration of 11 species along Bristol Bay (red-throated loon, Gavia stellata; Pacific loon, Gavia pacifica; pelagic cormorant, Phalacrocorax pelagicus; emperor goose, Chen canagica; brant; Steller's eider, Polysticta stellen; common eider, Somateria mollissima; king eider; black scoter, Melanina nigra; white-winged scoter, Melanina fusca; and surf scoter, Melanina perspicillatd). We document changes in nesting densities, differences in numbers, or habitat variations of 32 species in response to human activities (e.g., semipalmated plover, Charadrius semipalmatus; arctic tern, Sterna paradisaea; tree swallow, Tachycineta bicolor, varied thrush, Ixoreus naevius; yellow-rumped warbler, Dendroica coronata; and American tree sparrow, Spizella arborea). We report the changes in a major colony of Aleutian terns (Sterna aleatico) at irregular intervals over 50 years.

  6. Psoralea margaretiflora (Psoraleeae, Fabaceae): A new species from the Sneeuberg Centre of Floristic Endemism, Eastern Cape, South Africa

    PubMed Central

    Stirton, Charles H.; Clark, V. Ralph; Barker, Nigel P.; Muasya, A. Muthama

    2011-01-01

    Abstract A new species of Psoralea is described. Psoralea margaretiflora C.H. Stirton & V.R. Clark is endemic to the Sneeuberg Centre of Floristic Endemism, Eastern Cape, South Africa. This resprouter is characterised by its small greenish-white flowers with a small trifid purple nectar patch and translucent veins; 5(–7)-pinnate leaflets; multi-branching erect short seasonal flowering shoots; and tall habit of many stiff bare stems with the seasonal shoots massed at the apex. It is most similar to Psoralea oligophylla Eckl. & Zeyh., a widespread species found in the Eastern Cape. The reseeder Psoralea oligophylla differs in its lax virgate spreading habit with numerous long glaucous seasonal shoots; single stem, 1(–3)- glaucous leaflets; more numerous white flowers; and standard petals with a purple ring surrounding a bright yellow nectar patch. PMID:22171191

  7. Psoralea margaretiflora (Psoraleeae, Fabaceae): A new species from the Sneeuberg Centre of Floristic Endemism, Eastern Cape, South Africa.

    PubMed

    Stirton, Charles H; Clark, V Ralph; Barker, Nigel P; Muasya, A Muthama

    2011-01-01

    A new species of Psoralea is described. Psoralea margaretiflora C.H. Stirton & V.R. Clark is endemic to the Sneeuberg Centre of Floristic Endemism, Eastern Cape, South Africa. This resprouter is characterised by its small greenish-white flowers with a small trifid purple nectar patch and translucent veins; 5(-7)-pinnate leaflets; multi-branching erect short seasonal flowering shoots; and tall habit of many stiff bare stems with the seasonal shoots massed at the apex. It is most similar to Psoralea oligophylla Eckl. & Zeyh., a widespread species found in the Eastern Cape. The reseeder Psoralea oligophylla differs in its lax virgate spreading habit with numerous long glaucous seasonal shoots; single stem, 1(-3)- glaucous leaflets; more numerous white flowers; and standard petals with a purple ring surrounding a bright yellow nectar patch.

  8. Atlas of contaminants in the eggs of fish-eating colonial birds of the Great Lakes, 1993--1997: Volume 2 -- Accounts by chemical. Technical report series number 322

    SciTech Connect

    Pekarik, C.

    1998-01-01

    During 1993--97, the Canadian Wildlife Service collected 1,252 eggs from 32 fish-eating colonial water bird sites throughout the Great Lakes. The work was part of a monitoring program to understand the temporal and spatial trends of environmental contaminant levels in Great Lakes biota. Eggs of four species (double-crested cormorant, great black-backed gull, herring gull, and ring-billed gull) were sampled and analyzed for organochlorine pesticides, chlorinated benzenes, polychlorinated biphenyls (PCB), dioxins and furans, and lipid and moisture. This volume contains contaminant data for all four species summarized by compound.

  9. ETV REPORT AND VERIFICATION STATEMENT; EVALUATION OF LOBO LIQUIDS RINSE WATER RECOVERY SYSTEM

    EPA Science Inventory

    The Lobo Liquids Rinse Water Recovery System (Lobo Liquids system) was tested, under actual production conditions, processing metal finishing wastewater, at Gull Industries in Houston, Texas. The verification test evaluated the ability of the ion exchange (IX) treatment system t...

  10. 77 FR 22004 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ... Polar Skua, S. Giant Petrel, Blue- Eyed Shag, and Kelp Gulls), (3) obtain diet samples by stomach lavage...; (6) obtain tissue samples from adults and chicks (e.g. preen gland oil, blood, feathers, yolk);...

  11. ETV REPORT AND VERIFICATION STATEMENT - KASELCO POSI-FLO ELECTROCOAGULATION TREATMENT SYSTEM

    EPA Science Inventory

    The Kaselco Electrocoagulation Treatment System (Kaselco system) in combination with an ion exchange polishing system was tested, under actual production conditions, processing metal finishing wastewater at Gull Industries in Houston, Texas. The verification test evaluated the a...

  12. 76 FR 48183 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... biology of the Adelie, Gentoo and Chinstrap penguins, and interactions among these species and their..., 2700 Gentoo penguins, 250 Brown skua, 350 South polar skua, 600 Giant petrel, 100 Kelp gulls, 150...

  13. Atlas of contaminants in the eggs of fish-eating colonial birds of the Great Lakes, 1993--1997: Volume 1 -- Accounts by location. Technical report series number 321

    SciTech Connect

    Pekarik, C.

    1998-01-01

    During 1993--97, the Canadian Wildlife Service collected 1,252 eggs from 32 fish-eating colonial water bird sites throughout the Great Lakes. The work was part of a monitoring program to understand the temporal and spatial trends of environmental contaminant levels in Great Lakes biota. Eggs of four species (double-crested cormorant, great black-backed gull, herring gull, and ring-billed gull) were sampled and analyzed for organochlorine pesticides, chlorinated benzenes, polychlorinated biphenyls (PCB), dioxins and furans, and lipid and moisture. This volume contains contaminant data for all four species summarized by sample size and by location, as well as data on non-coplanar PCB congener patterns in herring gull eggs.

  14. Interspecific differences in the antioxidant capacity of two Laridae species exposed to metals.

    PubMed

    Espín, Silvia; Martínez-López, Emma; Jiménez, Pedro; María-Mojica, Pedro; García-Fernández, Antonio J

    2016-05-01

    The main aim of the present study was to assess the concentration of metals (Pb, Cd, Hg, Cu and Zn) in blood, and elucidate their potential effects on oxidative stress biomarkers in red blood cells of Audouin's gull (Ichthyaetus audouinii) and Slender-billed gull (Chroicocephalus genei) chicks in Southeastern Spain. For this purpose, total glutathione (GSH) content, antioxidant enzymes activities (glutathione peroxidase, GPx; superoxide dismutase, SOD; catalase, CAT and glutathione-S-transferase, GST), and lipid peroxidation (TBARS) were analyzed. In general, metal exposure in both species can be considered low, except for Hg in Audouin's gull. Our findings show higher antioxidant levels in Audouin's gull than in Slender-billed gull; probably due to a combination of different basal antioxidant capacity between species, and to an up-regulation of the antioxidant system in Audouin's gull as a response to the higher Hg, Cu and Zn concentrations. This could reduce the production of TBARS keeping them at lower levels than those found in Slender-billed gull. In spite of this, the significantly higher Hg levels found in Audouin's gull (13.6µg/dl wet weight) in comparison to Slender-billed gull (2.7µg/dl), likely related to their different diet and the former consuming discarded fish, were able to produce lipid peroxidation in this species. The positive effect of Hg on SOD activity in Slender-billed gull, and of Pb on GSH levels in Audouin's gull, could reflect the necessity of the organism to upregulate these antioxidants to balance the increased oxidative stress caused by metals. The degree of metal exposure seems to be essential in the response of the antioxidant system, which may suffer up or down-regulations depending on metal concentrations. This study supports the interactive effects of metals on oxidative stress biomarkers, the complexity of the antioxidant system and the close cooperation between antioxidants, which requires the study of several metals and

  15. Hourly Airport Activity Profiles: 30 Airports by User, 3 Airports by User and Equipment Type, Selected Days in June, July, and August 1978.

    DTIC Science & Technology

    1980-01-01

    PORTER PILATUS PL6A 5 TURBO PORTER PILATUS P136 6 ROYAL GULL PIAGGIO P166 6 SUPER GULL PIAGGIO P2 6 NEPTUNE LOCKHEED P3 5 ELECTRA/ORION LOCKHEED 147...SEA STAR LOCKHEED T2 4 BUCKEYE T20 ROCKWELL INT’L. T28 7 TROJAN ROCKWELL INT’L. T29 6 FLYING CLASSROOM 240 GEN. DYNAMICS T33 4 SHOOTING STAR LOCKHEED

  16. Coastal Geologic and Engineering History of Presque Isle Peninsula, Pennsylvania

    DTIC Science & Technology

    1993-08-01

    pebble gravel. These deposits, formed about 12,800 years ago ( Schooler 1974), have not been found to be suitable for use as beach fill because of a...placed annually during the period from 1975 to 1991, the growth rate at Gull Point has been as high as 350,000 cu yd per year from 1976 to 1978 (USAED...Modern Coastal Processes - A Sediment Budget ............... 25 Shoreline and Offshore Changes at Gull Point ............... 31 4 -Engineering History of

  17. Ingestion and dispersal: direct and indirect effects of frugivores on seed viability and germination of Corema album (Empetraceae)

    NASA Astrophysics Data System (ADS)

    Calviño-Cancela, María

    2004-07-01

    The effect of gulls, blackbirds and rabbits on the viability and germination of Corema album seeds are compared. Frugivores can affect seed viability and germination (1) directly, through the effect of ingestion and (2) indirectly, dispersing seeds to different sites with different conditions. These two major factors in the quality of a seed disperser are not necessarily concordant in direction and magnitude. Gulls and blackbirds have similar direct effects, being much better than those of rabbits, due to the low probability of germination of seeds within rabbit pellets. Seed germination occurs mainly in the open ground, particularly in the sparse scrub, and is very low under vegetation cover. This pattern becomes crucial determining the indirect effects of seed dispersers that will depend on their capacity to carry seeds to the most suitable sites for germination. Gulls and rabbits disperse most of seeds to open ground, exerting a positive indirect effect on germination, whereas blackbirds disperse seeds mainly under shrubs, thus exerting a negative indirect effect. Direct and indirect effects on seed germination are concordant for gulls but discordant for blackbirds and rabbits. Gulls were the best dispersers; the overall probability of germination for a seed dispersed by gulls was 17.59%. The quality of blackbirds and rabbits was relatively low (3.49% and 1.17%, respectively). Frugivores seem to be essential for germination of C. album seeds, not as much for their direct effects but for their ability to carry seeds to suitable sites.

  18. Human disturbance of an avian scavenging guild

    USGS Publications Warehouse

    Skagen, Susan K.; Knight, Richard L.; Orians, Gordon H.

    1991-01-01

    In order to investigate the effects of human activities on relationships within foraging guilds, we examined inacanus dynamics of eagles, crows, and gulls scavenging on spawned salmon in the Pacific Northwest. We examined several hypotheses that postulate the asymmetric foraging relationships of the three guild members and that reveal the influence of competition and facilitation in these relationships. Spatial and temporal patterns of resource use by the three primary guild members varied with the presence and absence of human activity at experimental feeding stations. At control (undisturbed) stations, eagles preferred to feed >100 m from vegetative cover, whereas gulls fed <50 m from cover. At experimental (disturbed) stations, eagles rarely fed, and feeding activity by gulls increased at both near and far stations. Crows often fed on alternate food sources in fields adjacent to the river, especially when salmon carcasses were scarce, whereas eagles and gulls rarely did so. We also examined if and how the behavior of single guild members changes in the presence or absence of other guild members. In the absence of eagles, gulls and crows preferred stations far from cover, numbers of both increased at feeding stations, birds were distributed nearer to carcasses, and they fed more. We emphasize that guild theory lends important insights to our understanding of the effects of human disturbance on wildlife communities.

  19. The hybrid bio-inspired aerial vehicle: Concept and SIMSCAPE flight simulation.

    PubMed

    Tao Zhang; Su, Steven; Nguyen, Hung T

    2016-08-01

    This paper introduces a Silver Gull-inspired hybrid aerial vehicle, the Super Sydney Silver Gull (SSSG), which is able to vary its structure, under different manoeuvre requirements, to implement three flight modes: the flapping wing flight, the fixed wing flight, and the quadcopter flight (the rotary wing flight of Unmanned Air Vehicle). Specifically, through proper mechanism design and flight mode transition, the SSSG can imitate the Silver Gull's flight gesture during flapping flight, save power consuming by switching to the fixed wing flight mode during long-range cruising, and hover at targeted area when transferring to quadcopter flight mode. Based on the aerodynamic models, the Simscape, a product of MathWorks, is used to simulate and analyse the performance of the SSSG's flight modes. The entity simulation results indicate that the created SSSG's 3D model is feasible and ready to be manufactured for further flight tests.

  20. Effects of No. 2 fuel oil on hatchability of marine and estuarine bird eggs

    USGS Publications Warehouse

    White, D.H.; King, K.A.; Coon, N.C.

    1979-01-01

    Eggs of Louisiana herons, sandwich terns, and laughing gulls were oiled with either 0, 5, or 20 microliter of No. 2 fuel oil in the field and in the laboratory. After 5 days of natural incubation, field-oiled and control eggs were opened and embryonic mortality was determined. No. 2 fuel oil produced 61% mortality in Louisiana heron eggs, 56% in sandwich tern eggs, and 83% in laughing gull eggs. Hatching success of artificially incubated, oiled eggs appeared to be lower than in control eggs. However, stress during shipment to the laboratory and problems within the incubator probably contributed to reduced hatchability in both groups.

  1. The Future of Work. Curriculum Development Project. Final Report.

    ERIC Educational Resources Information Center

    Center for New Work of Flint, MI.

    The Future of Work project grew out of an essay of the same title by Frithjof Bergmann, a philosophy professor at the University of Michigan. In spring 1983, Professor Bergmann and a colleague, Richard Gull, founded the Center for New Work of Flint in Michigan, where the problems besieging the U.S. auto industry were focusing attention on the…

  2. Effects of Fog Oil Smoke on Immune Responses in the House Sparrow (Passer domesticus) and Red-winged Blackbird (Agelaius phoeniceus)

    DTIC Science & Technology

    2004-09-01

    1987. “Enhanced immune responses in broiler chicks fed methionine-supplemented diets.” Poultry Sci. 66:1147-1154. White, J. 1992. “Protocol for the...Biol. Lab. 17:40-42. Miller, D. S., D. B. Peakall, and W. B. Kinter. 1978. “Ingestion of crude oil: sublethal effects in herring gull chicks

  3. A Day by the Sea

    ERIC Educational Resources Information Center

    Melber, Leah

    2006-01-01

    Quality science programs extend well beyond the classroom or school yard. A local shoreline is a great place for inquiry-based "science activities". Students can explore seaweed clumps, conduct a gull census, or implement an investigation of their own design.

  4. Reconcilable differences: the use of reference material to reduce methodological artifacts in the reporting of organochlorine pesticides and polychlorinated biphenyls.

    PubMed

    de Solla, Shane R; Weseloh, D V Chip; Letcher, Robert J; Hebert, Craig E

    2010-01-01

    Numerous long-term monitoring programs have assessed spatial and temporal trends of organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs). Changes in analytical approaches (e.g., gas chromatography coupled with electron capture detection [GC-ECD] versus mass spectrometric detection [GC-MSD]) can reveal artifacts in the reported concentrations. In-house reference material (RM) was used to determine the analytical artifacts in the measurement of OCs and PCBs in Great Lake herring gull eggs previously analyzed from 1994 to 1996 (GC-ECD) and 1997 to 1999 (GC-MSD). Approximately 19.0% of the variability of PCB congeners in gull eggs was associated with analytical artifacts, and differences among colonies were obscured. Although the discrepancy in sum PCBs (SigmaPCBs) was fairly small (2.1%), some congeners varied considerably between methods (> 60%). After statistically removing the artifacts, only 1.4% of the variability in PCBs of herring gull eggs was associated with artifacts, and differences among gull colonies became apparent. After excluding OCs near the detection limit in the RM, statistically removing the artifacts reduced some of the differences between methods for OCs. Analytical artifacts may potentially render inferences difficult, confounded, and erroneous. When combining contaminant data obtained using different methods, the methods should be assumed to give different results unless demonstrated otherwise. Assessments of the compatibility of analytical methodologies should be made using an appropriate RM.

  5. 33 CFR 207.340 - Reservoirs at headwaters of the Mississippi River; use and administration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Mississippi River; use and administration. 207.340 Section 207.340 Navigation and Navigable Waters CORPS OF... headwaters of the Mississippi River; use and administration. (a) Description. These reservoirs include Winnibigoshish, Leech Lake, Pokegama, Sandy Lake, Pine River and Gull Lake. (b) Penalties. The River and...

  6. 33 CFR 207.340 - Reservoirs at headwaters of the Mississippi River; use and administration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Mississippi River; use and administration. 207.340 Section 207.340 Navigation and Navigable Waters CORPS OF... headwaters of the Mississippi River; use and administration. (a) Description. These reservoirs include Winnibigoshish, Leech Lake, Pokegama, Sandy Lake, Pine River and Gull Lake. (b) Penalties. The River and...

  7. 33 CFR 207.340 - Reservoirs at headwaters of the Mississippi River; use and administration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Mississippi River; use and administration. 207.340 Section 207.340 Navigation and Navigable Waters CORPS OF... headwaters of the Mississippi River; use and administration. (a) Description. These reservoirs include Winnibigoshish, Leech Lake, Pokegama, Sandy Lake, Pine River and Gull Lake. (b) Penalties. The River and...

  8. Avian botulism: geographic expansion of a historic disease.

    USGS Publications Warehouse

    Locke, Louis N.; Friend, Milton

    1989-01-01

    Avian botulism is a paralytic, often fatal disease of birds resulting from ingestion of toxin produced by the bacterium Clostridium botulinum. Waterfowl die-offs from the botulism are usually caused by type C toxin; sporadic die-offs among fish-eating birds, such as common loons (Gavia immer) and gulls, have been caused by type E toxin.

  9. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

  10. Core competencies for natural resource negotiation

    USGS Publications Warehouse

    Gillette, S.C.; Lamb, B.L.

    2005-01-01

    Seabird colony sizes and movements were documented in the DelMarVa coastal region in 1976-1977 and in New Jersey in 1978-1979. Most colonies were found on marsh and dredge deposition islands and on barrier island beaches. For the 'traditionally' beach-nesting Herring Gull, Common Tern, and Black Skimmer, larger, more stable colonies were found on barrier beaches than on marsh islands. In marsh habitats, rates of colony-site change of marshnesting Forster's Tern and Laughing Gulls were similar to those of the former beach nesters. Several adaptations have evolved in marsh specialists to cope with a high risk of reproductive failure due to flooding, but both Herring Gulls and Common Terns also appear to be very adaptable in nesting under various habitat conditions. New colonies and those abandoned between years may be pioneering attempts by younger or inexperienced birds, because they are often smaller than persistent colonies, although patterns differ among areas and habitats. Colony-site dynamics are complex and result from many selective factors including competition, predation, physical changes in site structure, and flooding. The invasion of Herring Gulls into marshes along the mid-Atlantic coast has had an impact on new colony-site choice by associated seabirds. Calculating colony-site turnover rates allows for comparisons among species, habitats, and regions and may give useful insights into habitat quality and change and alternative nesting strategies

  11. The trophodynamics of PCBs in the Lake Ontario food web

    SciTech Connect

    Metcalfe, T.L.; Metcalfe, C.D.

    1995-12-31

    Samples of water, sediment, invertebrates, fish, and herring gull eggs were collected in north-central Lake Ontario and were analyzed to determine the concentrations of PCBs, including non-ortho substituted PCB congeners, in the benthic and pelagic components of the Lake Ontario food web. There was biomagnification of PCBs in the food web from benthic and planktonic invertebrates through to lake trout and gulls. However, all of the fish species had about the same lipid-normalized concentrations of PCBs. The relative proportions of the PCB congeners changed as they passed through the food web. An index of metabolism for each PCB congener was calculated by comparing the concentrations of PCB congeners in various predator/prey groupings within the food web. These data indicate that invertebrates, fish and gulls have different capabilities in metabolizing and eliminating specific PCB congeners. While tri and tetrachlorinated congeners with no chlorine substitution at meta-para carbons on the biphenyl ring were readily metabolized by all taxa, only gulls appeared to be capable of metabolizing the PCBs with no chlorine substitution at ortho-meta positions. The trophodynamics of nonortho substituted (coplanar) PCBs did not differ from other PCB congeners of similar chlorine number, which indicates that non-ortho congeners are not any more persistent in biota than other PCBs.

  12. Douglas YO-31A

    NASA Technical Reports Server (NTRS)

    1932-01-01

    Douglas YO-31A: The mockup model of the gull-winged Douglas YO-31A observation plane was tested in Langley's 30 x 60 Full Scale Tunnel during 1932. As part of the drag clean-up that was under examination of the YO-31, the model aircraft was 'flown' in the tunnel with and without the wheel fairings.

  13. Dover Schools' Unintelligent Design

    ERIC Educational Resources Information Center

    Barlow, Dudley

    2006-01-01

    The author of this article was surprised to read in the December 21, 2005, Ann Arbor News that "The Ann Arbor-based Thomas More Law Center, which represented the Dover [Pennsylvania] School District in its federal case for the teaching of intelligent design, has threatened to sue Gull Lake [Michigan] Community Schools over its policy that…

  14. Case report: an outbreak of streptococcosis in eared grebes (Podiceps nigricollis)

    USGS Publications Warehouse

    Jensen, W.I.

    1979-01-01

    An outbreak of streptococcosis (Streptococcus zooepidemicus), apparently the first recorded in wild birds, killed an estimated 7,500 eared grebes (Podiceps nigricollis) on Great Salt Lake (Utah) in November and December, 1977. Ducks and gulls feeding in the same area were unaffected.

  15. 33 CFR 207.340 - Reservoirs at headwaters of the Mississippi River; use and administration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintained: Winnibigoshish, 150 cubic feet per second. Leech Lake, 70 cubic feet per second. Pokegama, 200 cubic feet per second. Sandy Lake, 80 cubic feet per second. Pine River, 90 cubic feet per second. Gull Lake, 30 cubic feet per second. (3) During the season of navigation on the upper Mississippi River,...

  16. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  17. The Family Writing Project: Creating Space for Sustaining Teacher Identity

    ERIC Educational Resources Information Center

    McKinney, Marilyn; Lasley, Saralyn; Holmes-Gull, Rosemary

    2008-01-01

    Family writing projects can change the nature of classroom writing instruction and rejuvenate teachers. Marilyn McKinney, Saralyn Lasley, and Rosemary Holmes-Gull report on their study of one such project in an urban school district. Using the concept of "third space," they describe the influence of this family literacy program on…

  18. Molecular Epidemiology of Salmonella enterica Serovar Typhimurium Isolates Determined by Pulsed-Field Gel Electrophoresis: Comparison of Isolates from Avian Wildlife, Domestic Animals, and the Environment in Norway

    PubMed Central

    Refsum, Thorbjørn; Heir, Even; Kapperud, Georg; Vardund, Traute; Holstad, Gudmund

    2002-01-01

    The molecular epidemiology of 142 isolates of Salmonella enterica serovar Typhimurium from avian wildlife, domestic animals, and the environment in Norway was investigated using pulsed-field gel electrophoresis (PFGE) and computerized numerical analysis of the data. The bacterial isolates comprised 79 isolates from wild-living birds, including 46 small passerines and 26 gulls, and 63 isolates of nonavian origin, including 50 domestic animals and 13 environmental samples. Thirteen main clusters were discernible at the 90% similarity level. Most of the isolates (83%) were grouped into three main clusters. These were further divided into 20 subclusters at the 95% similarity level. Isolates from passerines, gulls, and pigeons dominated within five subclusters, whereas isolates from domestic animals and the environment belonged to many different subclusters with no predominance. The results support earlier results that passerines constitute an important source of infection to humans in Norway, whereas it is suggested that gulls and pigeons, based on PFGE analysis, represent only a minor source of human serovar Typhimurium infections. Passerines, gulls, and pigeons may also constitute a source of infection of domestic animals and feed plants or vice versa. Three isolates from cattle and a grain source, of which two were multiresistant, were confirmed as serovar Typhimurium phage type DT 104. These represent the first reported phage type DT 104 isolates from other sources than humans in Norway. PMID:12406755

  19. 76 FR 58649 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List Van Rossem...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... facsimile to 760- 431-9624. If you use a telecommunications device for the deaf (TDD), you may call the... recognize a western race'' (i.e., subspecies) of gull-billed tern in their authoritative review of the birds... its 1957 (fifth) edition of its checklist of North American birds (AOU 1957, p. 233), which was...

  20. 75 FR 32728 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List van Rossem's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-09

    ... telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800-877-8339... U.S.C. 2901 et seq.), our Division of Migratory Bird Management included the gull-billed tern (the species as a whole) in the list of Birds of Conservation Concern (USFWS 2002, pp. 1-99; USFWS 2008, pp....

  1. Seascapes: Glimpses of Our Water World.

    ERIC Educational Resources Information Center

    Hardin, Jan

    Presented is a collection of newspaper articles prepared by the Delaware Sea Grant Marine Advisory Service during the summer of 1978. Subjects addressed are bioluminescence, beachcomber finds, gulls, beach erosion, marine research activities, barnacles, sand, seaweed, jellyfish, shore restaurants, diving mammals, and tides. (Author/BW)