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Kreitsberg R, Nääb L, Meitern R, Carbillet J, Fort J, Giraudeau M, Sepp T. The effect of environmental pollution on gene expression of seabirds: A review. Mar Environ Res 2023; 189:106067. [PMID: 37393763 DOI: 10.1016/j.marenvres.2023.106067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/15/2023] [Accepted: 06/19/2023] [Indexed: 07/04/2023]
Abstract
One of the biggest challenges for ecotoxicologists is to detect harmful effects of contaminants on individual organisms before they have caused significant harm to natural populations. One possible approach for discovering sub-lethal, negative health effects of pollutants is to study gene expression, to identify metabolic pathways and physiological processes affected by contaminants. Seabirds are essential components of ecosystems but highly threatened by environmental changes. Being at the top of the food chain and exhibiting a slow pace of life, they are highly exposed to contaminants and to their ultimate impacts on populations. Here we provide an overview of the currently available seabird-related gene expression studies in the context of environmental pollution. We show that studies conducted, so far, mainly focus on a small selection of xenobiotic metabolism genes, often using lethal sampling protocols, while the greater promise of gene expression studies for wild species may lie in non-invasive procedures focusing on a wider range of physiological processes. However, as whole genome approaches might still be too expensive for large-scale assessments, we also bring out the most promising candidate biomarker genes for future studies. Based on the biased geographical representativeness of the current literature, we suggest expanding studies to temperate and tropical latitudes and urban environments. Also, as links with fitness traits are very rare in the current literature, but would be highly relevant for regulatory purposes, we point to an urgent need for establishing long-term monitoring programs in seabirds that would link pollutant exposure and gene expression to fitness traits.
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Affiliation(s)
- Randel Kreitsberg
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51003, Tartu, Estonia.
| | - Lisanne Nääb
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51003, Tartu, Estonia
| | - Richard Meitern
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51003, Tartu, Estonia
| | - Jeffrey Carbillet
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51003, Tartu, Estonia
| | - Jérôme Fort
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266, CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000, La Rochelle, France
| | - Mathieu Giraudeau
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266, CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000, La Rochelle, France
| | - Tuul Sepp
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51003, Tartu, Estonia
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2
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Power A, White P, McHugh B, McGovern E, Murphy S, Berrow S, Schlingermann M, Gately C, Tannian M, Newton S, Crowley D, O'Hea L, Boyle B, O'Connor I. Legacy and emerging contaminants in common guillemot Uria aalge eggs in Ireland and Wales. Chemosphere 2021; 283:131161. [PMID: 34144293 DOI: 10.1016/j.chemosphere.2021.131161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 06/12/2023]
Abstract
Guillemot eggs from multiple Irish colonies and one Welsh colony were analysed for legacy pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and other organochlorine compounds (OCs), as well as metals. Stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were measured in eggs to understand the influence of diet on contaminant levels detected. Wide-scope target and suspect screening techniques were used on a single guillemot egg, providing novel information on contaminants of emerging concern. Stable isotope ratio analysis showed that guillemots from Great Saltee Island and Lambay Island (Ireland's east coast) had a similar carbon source (δ13C) and fed at similar trophic levels (δ15N), pollutant levels were higher in eggs from Lambay Island near Dublin, Ireland's industrialised capital city. Guillemot eggs from Aughris Head (Atlantic west coast of Ireland), and Skomer Island (Wales) had differing isotopic niches to other colonies. Egg samples from Aughris Head had the lowest levels of pollutants in this study (with the exception of mercury) and amongst the lowest levels reported worldwide. In contrast, Skomer Island had the highest level of pollutants with higher concentrations of Σ16PCB, Σ6PBDE and HCB than Irish colonies, most likely a result of its proximity to historically industrial areas. Levels of PCBs, p,p' -DDE and mercury in guillemot eggs have decreased over time according to this study, in concurrence with worldwide trends. Levels of pollutants in guillemot eggs, in this study, fall below existing thresholds for adverse effects in other species, with the exception of mercury.
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Affiliation(s)
- Andrew Power
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland; Marine Institute, Oranmore, Co. Galway, Ireland.
| | - Philip White
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
| | | | | | - Sinéad Murphy
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
| | - Simon Berrow
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
| | - Moira Schlingermann
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
| | - Cillian Gately
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
| | | | | | | | - Linda O'Hea
- Marine Institute, Oranmore, Co. Galway, Ireland
| | - Brian Boyle
- Marine Institute, Oranmore, Co. Galway, Ireland
| | - Ian O'Connor
- Marine and Freshwater Research Centre, Galway-Mayo Institute of Technology, Galway, Ireland
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3
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Sayers CJ, Roeder MR, Forrette LM, Roche D, Dupont GLB, Apgar SE, Kocek AR, Cook AM, Shriver WG, Elphick CS, Olsen B, Bonter DN. Geographic variation of mercury in breeding tidal marsh sparrows of the northeastern United States. Ecotoxicology 2021; 30:1929-1940. [PMID: 34383236 DOI: 10.1007/s10646-021-02461-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
Saltmarsh sparrows (Ammospiza caudacuta) and seaside sparrows (A. maritima) are species of conservation concern primarily due to global sea-level rise and habitat degradation. Environmental mercury (Hg) contamination may present additional threats to their reproductive success and survival. To assess site-specific total mercury (THg) exposure and identify environmental correlates of THg detection, we sampled blood from adult male saltmarsh and seaside sparrows at 27 sites between Maine and Virginia, USA. The mean THg concentration (±1 SD) throughout the entire sampling range was 0.531 ± 0.287 µg/g wet weight (ww) for saltmarsh sparrows and 0.442 ± 0.316 µg/g ww for seaside sparrows. Individual THg concentrations ranged from 0.135-1.420 µg/g ww for saltmarsh sparrows and 0.153-1.530 µg/g ww for seaside sparrows. Model averaging from a suite of linear mixed models showed that saltmarsh sparrows averaged 20.1% higher blood THg concentrations than seaside sparrows, potentially due to differences in diet or foraging behavior. We found no evidence for a relationship between sparrow THg concentrations and land cover surrounding sampled marshes or average precipitation-based Hg deposition. Overall, our results suggest considerable, unexplained variation in tidal marsh sparrow blood THg concentrations over their co-occurring breeding ranges.
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Affiliation(s)
- Christopher J Sayers
- Department of Natural Resources & the Environment, Cornell University, Ithaca, NY, 14850, USA.
- Cornell Lab of Ornithology, Ithaca, NY, 14850, USA.
| | - Mackenzie R Roeder
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
| | - Lindsay M Forrette
- School of Marine Programs, University of New England, Biddeford, ME, 04005, USA
| | - Daniel Roche
- Division of Forestry and Natural Resources, Wildlife and Fisheries Resources Program, West Virginia University, Morgantown, WV, 26501, USA
| | - Gaetan L B Dupont
- Department of Organismic and Evolutionary Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Sam E Apgar
- Department of Ecology & Environmental Biology and Center of Biological Risk, University of Connecticut, Storrs, CT, 06269, USA
| | - Alison R Kocek
- Department of Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
| | - Alexandra M Cook
- Department of Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
| | - W Gregory Shriver
- Department of Entomology and Wildlife Ecology, University of Delaware, Newark, DE, 19716, USA
| | - Chris S Elphick
- Department of Ecology & Environmental Biology and Center of Biological Risk, University of Connecticut, Storrs, CT, 06269, USA
| | - Brian Olsen
- School of Biology and Ecology, University of Maine, Orono, ME, 04469, USA
| | - David N Bonter
- Department of Natural Resources & the Environment, Cornell University, Ithaca, NY, 14850, USA
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4
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Spickler JL, Swaddle JP, Gilson RL, Varian-Ramos CW, Cristol DA. Sexually selected traits as bioindicators: exposure to mercury affects carotenoid-based male bill color in zebra finches. Ecotoxicology 2020; 29:1138-1147. [PMID: 32862260 DOI: 10.1007/s10646-020-02271-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
To examine whether sexually selected traits are particularly sensitive bioindicators of environmental toxicants, we assessed the effects of exposure to environmentally relevant dietary concentrations of the pollutant methylmercury on pigment coloration in zebra finches (Taeniopygia guttata). First, we tested whether effects of methylmercury on coloration were influenced by timing of exposure. Birds were either exposed developmentally (up to 114 days after hatching), as adults (after reaching sexual maturity), or for their entire life. Bill coloration, which is a carotenoid-based, sexually selected trait, was less red in males with lifetime exposure to methylmercury, compared to controls. Neither adult, nor developmental exposure influenced bill color in adult males, with the possible exception of early exposure of nestlings. Among females, where bill color is not under strong sexual selection, neither lifetime nor adult exposure to methylmercury affected bill color. For males and females, there was no effect of either lifetime or adult methylmercury exposure on coloration of back feathers, which is a non-sexually-dimorphic, melanin-based trait that is not likely the result of sexual selection. This study is a comprehensive experimental test of the proposal that sexually selected traits may be particularly useful bioindicators of the stress imposed by environmental toxins such as methylmercury.
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Affiliation(s)
- Jessica L Spickler
- Department of Biology, Institute for Bird Behavior Studies, William & Mary, Williamsburg, VA, 23187, USA
| | - John P Swaddle
- Institute for Integrative Conservation, William & Mary, Williamsburg, VA, 23187, USA
| | - Rebecca L Gilson
- Department of Biology, Institute for Bird Behavior Studies, William & Mary, Williamsburg, VA, 23187, USA
| | | | - Daniel A Cristol
- Department of Biology, Institute for Bird Behavior Studies, William & Mary, Williamsburg, VA, 23187, USA.
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5
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Chételat J, Ackerman JT, Eagles-Smith CA, Hebert CE. Methylmercury exposure in wildlife: A review of the ecological and physiological processes affecting contaminant concentrations and their interpretation. Sci Total Environ 2020; 711:135117. [PMID: 31831233 DOI: 10.1016/j.scitotenv.2019.135117] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/15/2019] [Accepted: 10/21/2019] [Indexed: 05/12/2023]
Abstract
Exposure to methylmercury (MeHg) can result in detrimental health effects in wildlife. With advances in ecological indicators and analytical techniques for measurement of MeHg in a variety of tissues, numerous processes have been identified that can influence MeHg concentrations in wildlife. This review presents a synthesis of theoretical principals and applied information for measuring MeHg exposure and interpreting MeHg concentrations in wildlife. Mercury concentrations in wildlife are the net result of ecological processes influencing dietary exposure combined with physiological processes that regulate assimilation, transformation, and elimination. Therefore, consideration of both physiological and ecological processes should be integrated when formulating biomonitoring strategies. Ecological indicators, particularly stable isotopes of carbon, nitrogen, and sulfur, compound-specific stable isotopes, and fatty acids, can be effective tools to evaluate dietary MeHg exposure. Animal species differ in their physiological capacity for MeHg elimination, and animal tissues can be inert or physiologically active, act as sites of storage, transformation, or excretion of MeHg, and vary in the timing of MeHg exposure they represent. Biological influences such as age, sex, maternal transfer, and growth or fasting are also relevant for interpretation of tissue MeHg concentrations. Wildlife tissues that represent current or near-term bioaccumulation and in which MeHg is the predominant mercury species (such as blood and eggs) are most effective for biomonitoring ecosystems and understanding landscape drivers of MeHg exposure. Further research is suggested to critically evaluate the use of keratinized external tissues to measure MeHg bioaccumulation, particularly for less-well studied wildlife such as reptiles and terrestrial mammals. Suggested methods are provided to effectively use wildlife for quantifying patterns and drivers of MeHg bioaccumulation over time and space, as well as for assessing the potential risk and toxicological effects of MeHg on wildlife.
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Affiliation(s)
- John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Ottawa, ON K1A 0H3, Canada.
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, Oregon, 97331, United States
| | - Craig E Hebert
- Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Ottawa, ON K1A 0H3, Canada
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6
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Ackerman JT, Herzog MP, Evers DC, Cristol DA, Kenow KP, Heinz GH, Lavoie RA, Brasso RL, Mallory ML, Provencher JF, Braune BM, Matz A, Schmutz JA, Eagles-Smith CA, Savoy LJ, Meyer MW, Hartman CA. Synthesis of Maternal Transfer of Mercury in Birds: Implications for Altered Toxicity Risk. Environ Sci Technol 2020; 54:2878-2891. [PMID: 31870145 DOI: 10.1021/acs.est.9b06119] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Maternal transfer is a predominant route of methylmercury (MeHg) exposure to offspring. We reviewed and synthesized published and unpublished data on maternal transfer of MeHg in birds. Using paired samples of females' blood (n = 564) and their eggs (n = 1814) from 26 bird species in 6 taxonomic orders, we conducted a meta-analysis to evaluate whether maternal transfer of MeHg to eggs differed among species and caused differential toxicity risk to embryos. Total mercury (THg) concentrations in eggs increased with maternal blood THg concentrations; however, the proportion of THg transferred from females to their eggs differed among bird taxa and with maternal THg exposure. Specifically, a smaller proportion of maternal THg was transferred to eggs with increasing female THg concentrations. Additionally, the proportion of THg that was transferred to eggs at the same maternal blood THg concentration differed among taxonomic orders, with waterfowl (Anseriformes) transferring up to 382% more THg into their eggs than songbirds (Passeriformes). We provide equations to predict THg concentrations in eggs using female blood THg concentrations, and vice versa, which may help translate toxicity benchmarks across tissues and life stages. Our results indicate that toxicity risk of MeHg can vary among bird taxa due to differences in maternal transfer of MeHg to offspring.
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Affiliation(s)
- Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
| | - Mark P Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, Maine 04103, United States
| | - Daniel A Cristol
- College of William and Mary, CBiology Department, P.O. Box 8795, Williamsburg, Virginia 23187, United States
| | - Kevin P Kenow
- U.S. Geological Survey, Upper Midwest Environmental Sciences Center, 2630 Fanta Reed Road, La Crosse, Wisconsin 54603, United States
| | - Gary H Heinz
- U.S. Geological Survey, Patuxent Wildlife Research Center, BARC-East, Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States
| | - Raphael A Lavoie
- Groupe de Recherche Interuniversitaire en Limnologie et environnement aquatique (GRIL), Département de Sciences Biologiques, Université de Montréal, Pavillon Marie-Victorin, CP6128, Succ. Centre-ville, Montréal, Québec H3C 3J7, Canada
| | - Rebecka L Brasso
- Weber State University, Department of Zoology, 1415 Edvalson Drive, Ogden, Utah 84408, United States
| | - Mark L Mallory
- Acadia University, Biology Department, 15 University Drive, Wolfville, Nova Scotia B4P 2R6, Canada
| | - Jennifer F Provencher
- Acadia University, Biology Department, 15 University Drive, Wolfville, Nova Scotia B4P 2R6, Canada
| | - Birgit M Braune
- Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Raven Road, Ottawa, Ontario K1A 0H3, Canada
| | - Angela Matz
- U.S. Fish and Wildlife Service, 1011 East Tudor Road, Anchorage, Alaska 99503, United States
| | - Joel A Schmutz
- U.S. Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, Alaska 99508, United States
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, Oregon 97331, United States
| | - Lucas J Savoy
- Biodiversity Research Institute, 276 Canco Road, Portland, Maine 04103, United States
| | - Michael W Meyer
- Wisconsin Department of Natural Resources, 107 Sutliff Avenue, Rhinelander, Wisconsin 54501, United States
| | - C Alex Hartman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
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Zabala J, Meade AM, Frederick P. Variation in nestling feather mercury concentrations at individual, brood, and breeding colony levels: Implications for sampling mercury in birds. Sci Total Environ 2019; 671:617-621. [PMID: 30939314 DOI: 10.1016/j.scitotenv.2019.03.382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/19/2019] [Accepted: 03/24/2019] [Indexed: 06/09/2023]
Abstract
Nestling feathers are often used to monitor and estimate Hg exposure in birds. Decision-making and results of studies on effects of exposure to Hg depend on adequate estimation of [Hg] at the studied level, which in turn is sensitive to variation in [Hg] in sampling units. However, there is little information on how feather [Hg] varies within nestlings, between nest mates, or between broods. We sampled feathers from sibling great egret nestlings in three breeding colonies of the Everglades where birds were exposed to variable Hg levels through diet. We compared the deviation of samples from average [Hg] within four levels of aggregation: individual (different scapular feathers of the same individual); brood (samples from siblings in the same nest), breeding colonies; and the entire wetland ecosystem. We found, on average, little intra-individual (<2%) and intra-brood (<6%) differences in [Hg], and no effects of chick hatch order in feather [Hg]. Further, intra-brood variability was not statistically different from intra-individual variability in [Hg]. In contrast, there was much higher variation between broods within colonies (>20%) and within the entire wetland (>30%) that could bias estimates of exposure to Hg obtained through small sample sizes. We simulated the influence of inter-brood variability in estimates of exposure to Hg under different sample sizes, and we found that uncertainty decreases markedly with samples sizes >6, and suggest a sample size of 10 individuals from different nests for monitoring programs and to estimate Hg contamination in areas where no previous knowledge is available.
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Affiliation(s)
- Jabi Zabala
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL 32611, USA
| | - Ashley M Meade
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL 32611, USA
| | - Peter Frederick
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL 32611, USA.
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Zabala J, Rodriguez-Jorquera IA, Orzechowski SC, Frederick P. Non-lethal sampling of avian indicators reveals reliable geographic signals of mercury despite highly dynamic patterns of exposure in a large wetland. Environ Pollut 2019; 247:577-585. [PMID: 30708320 DOI: 10.1016/j.envpol.2019.01.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 01/10/2019] [Accepted: 01/16/2019] [Indexed: 06/09/2023]
Abstract
Mercury is a global contaminant with special relevance for aquatic food webs, where biomagnification can result in strong effects on apex predators. Non-lethal sampling of tissues such as blood and feathers is often used to assess mercury risk and spatiotemporal variability of mercury exposure on avian populations. However, the assumption that samples from individuals within a population are representative of local mercury exposure underpins those approaches. While this assumption may be justified, it is rarely expressed quantitatively. Further, the stability of the tissue/exposure relationship over time or space may depend on the sampling medium used, since some tissues and age classes may be better at reflecting local or short-term changes in exposure. Here, we present analyses of mercury concentrations from three tissues (albumen, blood and feathers) of the same individual great egret (Ardea alba) nestlings from breeding colonies in the Florida Everglades collected over three consecutive years. The interaction of year and colony location explained at least 50% of the observed variation in mercury concentration in all the sampled tissues. Annual colony-wide average Hg concentrations in any of the sampled tissues correlated with average Hg concentrations in the other two tissues from the same colony (R2 > 0.53 in every case), while concentrations in albumen, blood and feathers from the same individual correlated poorly (R2 < 0.23 in every case). We suggest that despite high variation between and within individuals of the same colony, annual colony-averaged mercury concentrations in albumen, nestling blood or feathers can be representative indicators of annual geographic differences in mercury exposure. These results support the use of non-lethal sampling of nestling tissues to reflect local mercury exposure over large spatial scales.
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Affiliation(s)
- Jabi Zabala
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, USA
| | - Ignacio A Rodriguez-Jorquera
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, USA; Centro de Humedales Río Cruces (CEHUM), Universidad Austral de Chile, Valdivia, Chile
| | - Sophia C Orzechowski
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, USA
| | - Peter Frederick
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, USA.
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Zabala J, Rodriguez-Jorquera IA, Orzechowski SC, Frederick P. Mercury Concentration in Nestling Feathers Better Predicts Individual Reproductive Success than Egg or Nestling Blood in a Piscivorous Bird. Environ Sci Technol 2019; 53:1150-1156. [PMID: 30626179 DOI: 10.1021/acs.est.8b05424] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Piscivorous birds are at high risk of mercury exposure in aquatic food webs, and their reproductive success is sensitive to methylmercury exposure. Although effects are convincingly shown in a handful of lab studies, sublethal effects at environmentally relevant concentrations in the field, where there is a range of other natural stressors, are not well delineated. Part of that uncertainty arises because mercury concentration (hereafter, [Hg]) in adult tissues used to assess Hg risk can be influenced by Hg values in wintering grounds or other nonrelated areas. Several studies have used nestling tissues under the assumption that they better represent local risk to breeding since nestlings consume locally derived food. However, the correlation between [Hg] in nestling tissues and local breeding success remains unassessed. We analyzed great egret ( Ardea alba) breeding parameters collected over 3 years (2015-2017) in the Everglades (Florida, USA). The Everglades is a large contiguous wetland with geographically dispersed wading bird breeding sites exposed to variable and biologically relevant ranges of mercury concentrations. We examined mercury concentrations in albumen and nestling blood and feathers as predictors of 6 measures of reproductive success at individual nests. Albumen [Hg] did not correlate with reproductive end points, and correlations with blood [Hg] were weak. Feather [Hg] correlated negatively with all of the posthatching endpoints and explained 8.3% of the variance in the probability of a laid egg resulting in a fledged chick. However, most of the observed failures were hatching failures, which were not explained by albumen [Hg], and other nestling tissues could therefore not be evaluated. While our results support the use of nestling feathers as indicators of site-specific mercury exposure, we discuss both advantages and possible limitations of using nestling feathers as indicators of local mercury exposure.
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Affiliation(s)
- Jabi Zabala
- Department of Wildlife Ecology and Conservation , University of Florida , Gainesville , Florida 32611 , United States
| | - Ignacio A Rodriguez-Jorquera
- Department of Wildlife Ecology and Conservation , University of Florida , Gainesville , Florida 32611 , United States
- Centro de Humedales Río Cruces (CEHUM) , Universidad Austral de Chile , Valdivia , Chile
| | - Sophia C Orzechowski
- Department of Wildlife Ecology and Conservation , University of Florida , Gainesville , Florida 32611 , United States
| | - Peter Frederick
- Department of Wildlife Ecology and Conservation , University of Florida , Gainesville , Florida 32611 , United States
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10
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Ackerman JT, Hartman CA, Herzog MP. Maternal transfer of mercury to songbird eggs. Environ Pollut 2017; 230:463-468. [PMID: 28688298 DOI: 10.1016/j.envpol.2017.06.099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/07/2017] [Accepted: 06/28/2017] [Indexed: 06/07/2023]
Abstract
We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6-10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R2 = 0.97) and tree swallows (R2 = 0.97) and (2) during mid to late incubation for tree swallows (R2 = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%-107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15-1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R2 < 0.01). We provide equations to translate mercury concentrations from maternal blood to eggs (and vice versa), which should facilitate comparisons among studies and help integrate toxicity benchmarks into a common tissue.
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Affiliation(s)
- Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States.
| | - C Alex Hartman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States
| | - Mark P Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States
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11
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Yu MS, Eng ML, Williams TD, Guigueno MF, Elliott JE. Assessment of neuroanatomical and behavioural effects of in ovo methylmercury exposure in zebra finches ( Taeniopygia guttata ). Neurotoxicology 2017; 59:33-9. [DOI: 10.1016/j.neuro.2017.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 12/25/2022]
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Peterson EK, Buchwalter DB, Kerby JL, LeFauve MK, Varian-Ramos CW, Swaddle JP. Integrative behavioral ecotoxicology: bringing together fields to establish new insight to behavioral ecology, toxicology, and conservation. Curr Zool 2017; 63:185-194. [PMID: 29491976 PMCID: PMC5804166 DOI: 10.1093/cz/zox010] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/08/2017] [Indexed: 12/31/2022] Open
Abstract
The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdisciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk for the survival of species and populations in an increasingly polluted world. We provide an integrative framework for behavioral ecotoxicology using Tinbergen’s four postulates (causation and mechanism, development and ontogeny, function and fitness, and evolutionary history and phylogenetic patterns). The aims of this review are: 1) to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2) to demonstrate how studying ecotoxicology can promote behavior research; and 3) to identify areas of behavioral ecotoxicology that require further attention to promote the integration and growth of the field.
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Affiliation(s)
- Elizabeth K Peterson
- Department of Biological Sciences, State University of New York-Albany, Albany, NY 12222, USA
| | - David B Buchwalter
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Jacob L Kerby
- Department of Biology, University of South Dakota, Vermillion, SD 57069, USA
| | - Matthew K LeFauve
- Department of Biological Sciences, George Washington University, Washington, DC 20052, USA
| | | | - John P Swaddle
- Biology Department, Institute for Integrative Bird Behavior Studies, College of William & Mary, Williamsburg, VA 23187-8795, USA
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13
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Fuchsman PC, Brown LE, Henning MH, Bock MJ, Magar VS. Toxicity reference values for methylmercury effects on avian reproduction: Critical review and analysis. Environ Toxicol Chem 2017; 36:294-319. [PMID: 27585374 DOI: 10.1002/etc.3606] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 05/28/2016] [Accepted: 08/29/2016] [Indexed: 06/06/2023]
Abstract
Effects of mercury (Hg) on birds have been studied extensively and with increasing frequency in recent years. The authors conducted a comprehensive review of methylmercury (MeHg) effects on bird reproduction, evaluating laboratory and field studies in which observed effects could be attributed primarily to Hg. The review focuses on exposures via diet and maternal transfer in which observed effects (or lack thereof) were reported relative to Hg concentrations in diet, eggs, or adult blood. Applicable data were identified for 23 species. From this data set, the authors identified ranges of toxicity reference values suitable for risk-assessment applications. Typical ranges of Hg effect thresholds are approximately 0.2 mg/kg to >1.4 mg/kg in diet, 0.05 mg/kg/d to 0.5 mg/kg/d on a dose basis, 0.6 mg/kg to 2.7 mg/kg in eggs, and 2.1 mg/kg to >6.7 mg/kg in parental blood (all concentrations on a wet wt basis). For Hg in avian blood, the review represents the first broad compilation of relevant toxicity data. For dietary exposures, the current data support TRVs that are greater than older, commonly used TRVs. The older diet-based TRVs incorporate conservative assumptions and uncertainty factors that are no longer justified, although they generally were appropriate when originally derived, because of past data limitations. The egg-based TRVs identified from the review are more similar to other previously derived TRVs but have been updated to incorporate new information from recent studies. While important research needs remain, a key recommendation is that species not yet tested for MeHg toxicity should be evaluated using toxicity data from tested species with similar body weights. Environ Toxicol Chem 2017;36:294-319. © 2016 SETAC.
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Ackerman JT, Eagles-Smith CA, Herzog MP, Hartman CA, Peterson SH, Evers DC, Jackson AK, Elliott JE, Vander Pol SS, Bryan CE. Avian mercury exposure and toxicological risk across western North America: A synthesis. Sci Total Environ 2016; 568:749-769. [PMID: 27093907 PMCID: PMC5365029 DOI: 10.1016/j.scitotenv.2016.03.071] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 05/20/2023]
Abstract
Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that are directly relevant to bird reproduction. Results indicate that mercury contamination of birds is prevalent in many areas throughout western North America, and large-scale ecological attributes are important factors influencing bird mercury concentrations.
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Affiliation(s)
- Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States.
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, Oregon, 97331, United States
| | - Mark P Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
| | - C Alex Hartman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
| | - Sarah H Peterson
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, California 95620, United States
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, Maine, 04103, United States
| | - Allyson K Jackson
- Oregon State University, Department of Fisheries and Wildlife, 104 Nash Hall, Corvallis, Oregon, 97331, United States
| | - John E Elliott
- Environment Canada, Science and Technology Branch, Pacific Wildlife Research Centre, Delta, British Columbia, V4K 3N2, Canada
| | - Stacy S Vander Pol
- National Institute of Standards and Technology, Chemical Sciences Division, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, South Carolina, 29412, United States
| | - Colleen E Bryan
- National Institute of Standards and Technology, Chemical Sciences Division, Hollings Marine Laboratory, 331 Fort Johnson Road, Charleston, South Carolina, 29412, United States
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Buck KA, Varian-Ramos CW, Cristol DA, Swaddle JP. Blood Mercury Levels of Zebra Finches Are Heritable: Implications for the Evolution of Mercury Resistance. PLoS One 2016; 11:e0162440. [PMID: 27668745 PMCID: PMC5036838 DOI: 10.1371/journal.pone.0162440] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 08/23/2016] [Indexed: 11/18/2022] Open
Abstract
Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata) on standardized diets ranging from 0.0-2.4 μg/g methylmercury. We applied a quantitative genetics approach to examine patterns of variation and heritability of mercury accumulation within dietary treatments using a method of mixed effects modeling known as the 'animal model'. Significant variation in blood mercury accumulation existed within each treatment for birds exposed at the same dietary level; moreover, this variation was highly repeatable for individuals. We observed substantial genetic variation in blood mercury accumulation for birds exposed at intermediate dietary concentrations. Taken together, this is evidence that genetic variation for factors affecting blood mercury accumulation could be acted on by selection. If similar heritability for mercury accumulation exists in wild populations, selection could result in genetic differentiation for populations in contaminated locations, with possible consequences for mercury biomagnification in food webs.
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Affiliation(s)
- Kenton A. Buck
- Institute for Integrative Bird Behavior Studies, College of William and Mary, Williamsburg, Virginia, United States of America
| | - Claire W. Varian-Ramos
- Biology Department, Colorado State University – Pueblo, Pueblo, Colorado, United States of America
| | - Daniel A. Cristol
- Institute for Integrative Bird Behavior Studies, College of William and Mary, Williamsburg, Virginia, United States of America
| | - John P. Swaddle
- Institute for Integrative Bird Behavior Studies, College of William and Mary, Williamsburg, Virginia, United States of America
- * E-mail:
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Ackerman JT, Eagles-Smith CA, Herzog MP, Yee JL, Hartman CA. Egg-laying sequence influences egg mercury concentrations and egg size in three bird species: Implications for contaminant monitoring programs. Environ Toxicol Chem 2016; 35:1458-1469. [PMID: 26505635 DOI: 10.1002/etc.3291] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 10/11/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
Bird eggs are commonly used in contaminant monitoring programs and toxicological risk assessments, but intraclutch variation and sampling methodology could influence interpretability. The authors examined the influence of egg-laying sequence on egg mercury concentrations and burdens in American avocets, black-necked stilts, and Forster's terns. The average decline in mercury concentrations between the first and last eggs laid was 33% for stilts, 22% for terns, and 11% for avocets, and most of this decline occurred between the first and second eggs laid (24% for stilts, 18% for terns, and 9% for avocets). Trends in egg size with egg-laying order were inconsistent among species, and overall differences in egg volume, mass, length, and width were <3%. The authors summarized the literature, and among 17 species studied, mercury concentrations generally declined by 16% between the first and second eggs laid. Despite the strong effect of egg-laying sequence, most of the variance in egg mercury concentrations still occurred among clutches (75-91%) rather than within clutches (9%-25%). Using simulations, the authors determined that accurate estimation of a population's mean egg mercury concentration using only a single random egg from a subset of nests would require sampling >60 nests to represent a large population (10% accuracy) or ≥14 nests to represent a small colony that contained <100 nests (20% accuracy). Environ Toxicol Chem 2016;35:1458-1469. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.
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Affiliation(s)
- Joshua T Ackerman
- US Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California
| | - Collin A Eagles-Smith
- US Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon
| | - Mark P Herzog
- US Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California
| | - Julie L Yee
- US Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California
| | - C Alex Hartman
- US Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California
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Ackerman JT, Eagles-Smith CA, Herzog MP, Hartman CA. Maternal transfer of contaminants in birds: Mercury and selenium concentrations in parents and their eggs. Environ Pollut 2016; 210:145-154. [PMID: 26708769 DOI: 10.1016/j.envpol.2015.12.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/07/2015] [Accepted: 12/08/2015] [Indexed: 06/05/2023]
Abstract
We conducted a detailed assessment of the maternal transfer of mercury and selenium to eggs in three bird species (n = 107 parents and n = 339 eggs), and developed predictive equations linking contaminant concentrations in eggs to those in six tissues of the mother (blood, muscle, liver, kidney, breast feathers, and head feathers). Mercury concentrations in eggs were positively correlated with mercury concentrations in each of the mother's internal tissues (R(2) ≥ 0.95), but generally not with feathers. For each species, the proportion of mercury transferred to eggs decreased as mercury concentrations in the mother increased. At the same maternal mercury concentration, the proportion of mercury transferred to eggs differed among species, such that Forster's tern (Sterna forsteri) and black-necked stilt (Himantopus mexicanus) females transferred more methylmercury to their eggs than American avocet (Recurvirostra americana) females. Selenium concentrations in eggs also were correlated with selenium concentrations in the mother's liver (R(2) = 0.87). Furthermore, mercury and selenium concentrations in tern eggs were positively correlated with those in the father (R(2) = 0.84). Incubating male terns had 21% higher mercury concentrations in blood compared to incubating females at the same egg mercury concentration. We provide equations to predict contaminant concentrations in eggs from each of the commonly sampled bird tissues.
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Affiliation(s)
- Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States.
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331, United States
| | - Mark P Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States
| | - C Alex Hartman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States
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