| organochlorine-associated immunosuppression in prefledgling caspian terns and herring gulls from the great lakes: an ecoepidemiological study. | the objectives of study were to determine whether contaminant-associated immunosuppression occurs in prefledgling herring gulls and caspian terns from the great lakes and to evaluate immunological biomarkers for monitoring health effects in wild birds. during 1992 to 1994, immunological responses and related variables were measured in prefledgling chicks at colonies distributed across a broad gradient of organochlorine contamination (primarily polychlorinated biphenyls), which was measured in eg ... | 1996 | 8880006 |
| associations between altered immune function and organochlorine contamination in young caspian terns (sterna caspia) from lake huron, 1997-1999. | previous studies of laboratory animals and wildlife species have demonstrated the immunotoxicity of organochlorines. this study confirmed that associations between organochlorines and suppressed t cell function and enhanced antibody production in young caspian terns from the great lakes, first observed in the early 1990s, continued into the late 1990s. these associations were based on measurement of organochlorines in plasma of individuals and pooled egg samples. during 1997-99, immune function, ... | 2001 | 11280967 |
| effect of in ovo exposure to an organochlorine mixture extracted from double crested cormorant eggs (phalacrocorax auritus) and pcb 126 on immune function of juvenile chickens. | organochlorine (oc) contaminants including polychlorinated biphenyls (pcbs) and p, p'-dichlorodiphenyldichloroethylene (dde) have been associated with immune modulation in wild fish-eating birds from the great lakes. the objective of this study was to evaluate the immune function of juvenile chickens after in ovo exposure to pcb 126 or an environmentally relevant oc mixture extracted from eggs of double crested cormorants (phalacrocorax auritus) from green bay, lake michigan, usa. fertile white ... | 2007 | 17882474 |
| species differences in the sensitivity of avian embryos to methylmercury. | 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 ... | 2009 | 18421496 |
| ecosystem-based management of predator-prey relationships: piscivorous birds and salmonids. | predator-prey relationships are often altered as a result of human activities. where prey are legally protected, conservation action may include lethal predator control. in the columbia river basin (pacific northwest, usa and canada), piscivorous predators have been implicated in contributing to a lack of recovery of several endangered anadromous salmonids (oncorhynchus spp.), and lethal and nonlethal control programs have been instituted against both piscine and avian species. to determine the ... | 2008 | 18488627 |
| uvs is rare in seabirds. | ultraviolet-sensitive vision (uvs), believed to have evolved from an ancestral state of violet-sensitive vision (vs), is widespread among terrestrial birds, where it is thought to play a role in orientation, foraging, and sexual selection. less is known, however, about the distribution and significance of uvs in seabirds. to date uvs has been definitively demonstrated only in two families (laridae and sternidae), although indirect evidence has been used to argue for a more widespread occurrence. ... | 2011 | 21527267 |
| mercury exposure may influence fluctuating asymmetry in waterbirds. | variation in avian bilateral symmetry can be an indicator of developmental instability in response to a variety of stressors, including environmental contaminants. the authors used composite measures of fluctuating asymmetry to examine the influence of mercury concentrations in 2 tissues on fluctuating asymmetry within 4 waterbird species. fluctuating asymmetry increased with mercury concentrations in whole blood and breast feathers of forster's terns (sterna forsteri), a species with elevated m ... | 2017 | 27862225 |
| selenium bioaccumulation and body condition in shorebirds and terns breeding in san francisco bay, california, usa. | the present study evaluated se bioaccumulation in four waterbird species (n=206 birds) that breed within san francisco bay, california, u.s.a.: american avocets (recurvirostra americana), black-necked stilts (himantopus mexicanus), forster's terns (sterna forsteri), and caspian terns (hydroprogne caspia). selenium concentrations were variable and influenced by several factors, including species, region, reproductive stage, age, and sex. adult se concentrations (microg/g dry wt) in livers ranged ... | 2009 | 19459720 |
| mercury bioaccumulation and risk to three waterbird foraging guilds is influenced by foraging ecology and breeding stage. | we evaluated mercury (hg) in five waterbird species representing three foraging guilds in san francisco bay, ca. fish-eating birds (forster's and caspian terns) had the highest hg concentrations in their tissues, but concentrations in an invertebrate-foraging shorebird (black-necked stilt) were also elevated. foraging habitat was important for hg exposure as illustrated by within-guild differences, where species more associated with marshes and salt ponds had higher concentrations than those mor ... | 2009 | 19398255 |
| mercury demethylation in waterbird livers: dose-response thresholds and differences among species. | we assessed methylmercury (mehg) demethylation in the livers of adults and chicks of four waterbird species that commonly breed in san francisco bay: american avocets, black-necked stilts, caspian terns, and forster's terns. in adults (all species combined), we found strong evidence for a threshold model where mehg demethylation occurred above a hepatic total mercury concentration threshold of 8.51 +/- 0.93 microg/g dry weight, and there was a strong decline in %mehg values as total mercury (thg ... | 2009 | 18937537 |
| mercury correlations among six tissues for four waterbird species breeding in san francisco bay, california, usa. | despite a large body of research concerning mercury (hg) in birds, no single tissue has been used consistently to assess hg exposure, and this has hampered comparisons across studies. we evaluated the relationships of hg concentrations among tissues in four species of waterbirds (american avocets [recurvirostra americana], black-necked stilts [himantopus mexicanus], caspian terns [hydroprogne caspia; formerly sterna caspia], and forster's terns [sterna forsteri]) and across three life stages (pr ... | 2008 | 18444697 |
| contaminants of emerging concern in caspian tern compared to herring gull eggs from michigan colonies in the great lakes of north america. | 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 tw ... | 2017 | 28089466 |
| tracking overwintering areas of fish-eating birds to identify mercury exposure. | migration patterns are believed to greatly influence concentrations of contaminants in birds due to accumulation in spatially and temporally distinct ecosystems. two species of fish-eating birds, the double-crested cormorant (phalacrocorax auritus) and the caspian tern (hydroprogne caspia) breeding in lake ontario were chosen to measure the impact of overwintering location on mercury concentrations ([hg]). we characterized (1) overwintering areas using stable isotopes of hydrogen (δ(2)h) and ban ... | 2015 | 25514043 |
| contamination of mercury during the wintering period influences concentrations at breeding sites in two migratory piscivorous birds. | many aquatic fish-eating birds migrate long distances and are exposed to different mercury concentrations ([hg]) during their annual cycle. here we examined the importance of migration on [hg] in two colonial migratory fish-eating bird species. we determined temporal trends of [hg] and stable isotopes of carbon (δ(13)c) and nitrogen (δ(15)n) during the annual cycle in double-crested cormorants (phalacrocorax auritus) and caspian terns (hydroprogne caspia) breeding in lake ontario by a repeated s ... | 2014 | 25380025 |
| estimating migratory connectivity of birds when re-encounter probabilities are heterogeneous. | understanding the biology and conducting effective conservation of migratory species requires an understanding of migratory connectivity - the geographic linkages of populations between stages of the annual cycle. unfortunately, for most species, we are lacking such information. the north american bird banding laboratory (bbl) houses an extensive database of marking, recaptures and recoveries, and such data could provide migratory connectivity information for many species. to date, however, few ... | 2014 | 24967083 |
| mercury trends in colonial waterbird eggs downstream of the oil sands region of alberta, canada. | mercury levels were measured in colonial waterbird eggs collected from two sites in northern alberta and one site in southern alberta, canada. northern sites in the peace-athabasca delta and lake athabasca were located in receiving waters of the athabasca river which drains the oil sands industrial region north of fort mcmurray, alberta. temporal trends in egg mercury (hg) levels were assessed as were egg stable nitrogen isotope values as an indicator of dietary change. in northern alberta, cali ... | 2013 | 24070029 |
| use of fatty acid analysis to determine dispersal of caspian terns in the columbia river basin, usa. | lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. in populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. within the columbia river basin (washington, u.s.a.), avian predators forage at dams because dams tend to reduce rates of emigration of juvenile salmonids ( ... | 2011 | 21771078 |
| oxidative stress response of forster's terns (sterna forsteri) and caspian terns (hydroprogne caspia) to mercury and selenium bioaccumulation in liver, kidney, and brain. | bioindicators of oxidative stress were examined in prebreeding and breeding adult and chick forster's terns (sterna forsteri) and in prebreeding adult caspian terns (hydroprogne caspia) in san francisco bay, california. highest total mercury (thg) concentrations (mean ± standard error; µg/g dry wt) in liver (17.7 ± 1.7), kidney (20.5 ± 1.9), and brain (3.0 ± 0.3) occurred in breeding adult forster's terns. the thg concentrations in liver were significantly correlated with hepatic depletion of re ... | 2011 | 21194179 |
| organochlorine and pbde concentrations in relation to cytochrome p450 activity in livers of forster's terns (sterna forsteri) and caspian terns (hydroprogne caspia), in san francisco bay, california. | we measured halogenated organic contaminants (hocs) [polybrominated diphenyl ethers (pbdes), polychlorinated biphenyls (pcbs), and dichloro-diphenyl-trichloroethane (ddt)] and p450 [e.g., ethoxyresorufin-o-dealkylase (erod)] stress in livers from caspian tern (hydroprogne caspia) adults and forster's tern (sterna forsteri) adults and chicks in san francisco bay (sfb). penta bdes and tetra pbdes composed 46-66% of sigmapbde in terns. pcb homologues di, tri, penta, hexa, and hepta composed 93-95% ... | 2010 | 19653030 |
| concentrations and time trends of polybrominated diphenyl ethers (pbdes) and polychlorinated biphenyls (pcbs) in aquatic bird eggs from san francisco bay, ca 2000-2003. | concentrations of polybrominated diphenyl ethers (pbdes) and polychlorinated biphenyls (pcbs) were measured in 169 avian eggs. we analyzed randomly collected eggs of two species of piscivorous birds: caspian tern (sterna caspia) (n=78) and forster's tern (sterna forsteri) (n=76). we also analyzed fail-to-hatch eggs from two species protected under the federal endangered species act of 1973, that breed in the san francisco bay region: the piscivorous california least tern (sterna antillarum brown ... | 2008 | 18466953 |
| cost-effective management alternatives for snake river chinook salmon: a biological-economic synthesis. | the mandate to increase endangered salmon populations in the columbia river basin of north america has created a complex, controversial resource-management issue. we constructed an integrated assessment model as a tool for analyzing biological-economic trade-offs in recovery of snake river spring- and summer-run chinook salmon (oncorhynchus tshawytscha). we merged 3 frameworks: a salmon-passage model to predict migration and survival of smolts; an age-structured matrix model to predict long-term ... | 2008 | 18402583 |
| geographic variation in blood plasma protein concentrations of young herring gulls (larus argentatus) and caspian terns (sterna caspia) from the great lakes and lake winnipeg. | relative and total amounts of plasma protein fractions are affected by infections, inflammation, and nutritional and physiological status, and are therefore important health indicators in free-living animals. our objectives were: (1) to examine intercolony differences in plasma protein fractions in prefledgling gulls and terns; (2) to investigate relationships between plasma proteins and other physiological measures such as weight loss, growth, and immune function; and (3) to examine potential a ... | 2000 | 11790357 |
| contaminants in eggs of colonial waterbirds and hepatic cytochrome p450 enzyme levels in pipped tern embryos, washington state. | eggs of forster's terns (sterna forsteri) collected in 1991 from nesting colonies on crescent island (columbia river) and the potholes reservoir in south central washington generally contained low residues of organochlorine pesticides and metabolites, 2,3,7, 8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and polychlorinated biphenyls (pcbs). hepatic cytochrome p450 enzyme activity in pipped embryos of forster's terns from the two colonies seemed unaffected by contaminants. at cr ... | 1998 | 9732482 |
| embryonic abnormalities and organochlorine contamination in double-crested cormorants (phalacrocorax auritus) and caspian terns (hydroprogne caspia) from the upper great lakes in 1988. | persistent organochlorine contaminants including polychlorinated dibenzo-p-dioxins (pcdds), polychlorinated dibenzofurans (pcdfs) and polychlorinated biphenyls (pcbs) were determined in eggs with normal and deformed embryos collected in 1988 from different colonies during an epizootiological survey of double-crested cormorants (phalacrocorax auritus) and caspian terns (hydroprogne caspia) from the upper great lakes. pcbs and p,p'-dde were found in the highest concentrations in eggs of both speci ... | 1993 | 15091901 |
| great lakes embryo mortality, edema, and deformities syndrome (glemeds) in colonial fish-eating birds: similarity to chick-edema disease. | several species of colonial fish-eating birds nesting in the great lakes basin, including herring gulls, common terns and double-crested cormorants, have exhibited chronic impairment of reproduction. in addition to eggshell thinning caused by high levels of ddt and metabolites, the reproductive impairment is characterized by high embryonic and chick mortality, edema, growth retardation, and deformities, hence the name great lakes embryo mortality, edema, and deformities syndrome (glemeds). the h ... | 1991 | 1875430 |
| effects of mercury, selenium, and organochlorine contaminants on reproduction of forster's terns and black skimmers nesting in a contaminated texas bay. | mean mercury (0.40 micrograms/g), and geometric mean dde (1.6 micrograms/g) and polychlorinated biphenyl (pcb) (2.3 micrograms/g) concentrations in forster's tern (sterna forsteri) eggs from lavaca bay were higher than those in tern eggs from a reference area in san antonio bay, but residues were not correlated with hatching success. nest success was similar between bays. selenium levels in lavaca bay tern eggs (0.71 micrograms/g) were also comparable to those in eggs from the reference area (0. ... | 1991 | 1899991 |
| organochlorine contaminants in eggs of common terns from the canadian great lakes, 1981. | to determine if contaminant levels in common terns had changed over the last decade, we collected and analyzed eggs from four nesting colonies on the three lower great lakes during 1981. dde and pcbs were detected in every egg from the four colonies. dieldrin, mirex and trans-nonachlor were detected in more than 45% of the eggs. seven other organochlorine contaminants (ddd, ddt, hexachlorobenzene, oxychlordane, cis-chlordane, cis-nonachlor and toxaphene) were detected in less than 25% of the egg ... | 1989 | 15092410 |
| galactosomum otepotiense n. sp. (trematoda: heterophyidae) infecting four different species of fish-eating birds in new zealand: genetically identical but morphologically variable. | trematodes of the genus galactosomum are cosmopolitan parasites that infect the intestines of fish-eating birds and mammals. adults of named galactosomum species have not been recorded from bird hosts in new zealand, despite their cercarial stage being known from various studies of the first intermediate host, zeacumantus subcarinatus. here we describe a new species of galactosomum infecting four different piscivorous birds in new zealand: caspian terns, red-billed and black-backed gulls and lit ... | 2019 | 31500672 |
| seabirds as regional biomonitors of legacy toxicants on an urbanized coastline. | seabirds are often cited as sentinels of the marine environment, but are rarely used in traditional ocean and coastal contaminant monitoring. four classes of persistent organic pollutants (pops, n=68) and three trace elements (mercury, selenium, and arsenic) were measured in the eggs of california least terns (sterna antillarum browni), caspian terns (hydroprogne caspia), double-crested cormorants (phalacrocorax auritus), and western gulls (larus occidentalis) that nest in the southern californi ... | 2018 | 29156266 |
| measuring the additive effects of predation on prey survival across spatial scales. | the degree to which predation is an additive vs. compensatory source of mortality is fundamental to understanding the effects of predation on prey populations and evaluating the efficacy of predator management actions. in the columbia river basin, usa, predation by caspian terns (hydroprogne caspia) on u.s. endangered species act (esa)-listed juvenile salmonids (smolts; oncorhynchus spp.) has led to predator management actions to reduce predation; however, the assumption that reduced predation t ... | 2020 | 32524686 |