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Maute K, Story P, Hose GC, Warden A, Dojchinov G, French K. Observations on populations of a small insectivorous bird,. AUST J ZOOL 2022. [DOI: 10.1071/zo22006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The use of chemical pesticides to manage locust populations in natural ecosystems is likely to impact non-target arthropods and their predators. However, the relative effects of different locust control applications on Australian birds are unknown. Aerial applications of fipronil and fenitrothion are examples of two pesticides used in locust control in semiarid Australia. To test the relative impacts of pesticides on non-target fauna, pesticides were applied to replicate sites using aerial ultra-low-volume application methods. The body condition and biomarkers of pesticide exposure in resident white-winged fairy wrens (Malurus leucopterus leuconotus) at treatment and control sites were measured for two weeks before and after treatments. No measures suggested negative impacts of pesticide applications. However, birds monitored at treatment sites gained mass, possibly due to indirect impacts of pesticides on bird feeding patterns or the availability or behaviour of insect prey. Bird mass measures remained high at fipronil sites, whereas the mass of birds at fenitrothion sites returned to baseline levels within one week. As this study was conducted during dry conditions, when locust plagues are less likely, future insecticide research should also consider the availability of insect prey, its effect on insectivore feeding behaviour and the interaction of rainfall events.
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Costantini D, Blévin P, Bustnes JO, Esteve V, Gabrielsen GW, Herzke D, Humann-Guilleminot S, Moe B, Parenteau C, Récapet C, Bustamante P, Chastel O. Integument carotenoid-based colouration reflects contamination to perfluoroalkyl substances, but not mercury, in arctic black-legged kittiwakes. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.952765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Anthropogenic activities are introducing multiple chemical contaminants into ecosystems that act as stressors for wildlife. Perfluoroalkyl substances (PFAS) and mercury (Hg) are two relevant contaminants that may cause detrimental effects on the fitness of many aquatic organisms. However, there is a lack of information on their impact on the expression of secondary sexual signals that animals use for mate choice. We have explored the correlations between integument carotenoid-based colourations, blood levels of carotenoids, and blood levels of seven PFAS and of total Hg (THg) in 50 adult male black-legged kittiwakes (Rissa tridactyla) from the Norwegian Arctic during the pre-laying period, while controlling for other colouration influencing variables such as testosterone and body condition. Kittiwakes with elevated blood concentrations of PFAS (PFOSlin, PFNA, PFDcA, PFUnA, or PFDoA) had less chromatic but brighter bills, and brighter gape and tongue; PFOSlin was the pollutant with the strongest association with bill colourations. Conversely, plasma testosterone was the only significant correlate of hue and chroma of both gape and tongue, and of hue of the bill. Kittiwakes with higher concentrations of any PFAS, but not of THg, tended to have significantly higher plasma concentrations of the carotenoids astaxanthin, zeaxanthin, lutein, and cryptoxanthin. Our work provides the first correlative evidence that PFAS exposure might interfere with the carotenoid metabolism and the expression of integument carotenoid-based colourations in a free-living bird species. This outcome may be a direct effect of PFAS exposure or be indirectly caused by components of diet that also correlate with elevated PFAS concentrations (e.g., proteins). It also suggests that there might be no additive effect of THg co-exposure with PFAS on the expression of colourations. These results call for further work on the possible interference of PFAS with the expression of colourations used in mate choice.
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Su T, He C, Jiang A, Xu Z, Goodale E, Qiu G. Passerine bird reproduction does not decline in a highly-contaminated mercury mining district of China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117440. [PMID: 34062385 DOI: 10.1016/j.envpol.2021.117440] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 04/27/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
Mercury (Hg) is a neurotoxic element with severe effects on humans and wildlife. Widely distributed by atmospheric deposition, it can also be localized near point sources such as mines. Mercury has been shown to reduce the reproduction of bird populations in field observations in North America and Europe, but studies are needed in Asia, where the majority of emissions now occur. We investigated the reproduction of two passerines, Japanese Tit (Parus minor) and Russet Sparrow (Passer rutilans), in a large-scale Hg mining district, and a non-mining district, both in Guizhou, southwest China. Concentrations of Hg were elevated in the mining district (blood levels of 2.54 ± 2.21 [SD] and 0.71 ± 0.40 μg/g, in adult tits and sparrows, respectively). However, we saw no evidence of decreased breeding there: metrics such as egg volume, nestling weight, hatching and fledgling success, were all similar between the different districts across two breeding seasons. Nor were there correlations at the mining district between Hg levels of adults or juveniles, and hatching or fledgling success, or nestling weight. Nest success was high even in the mining district (tit, 64.0%; sparrow: 83.1%). This lack of reproductive decline may be related to lower blood levels in nestlings (means < 0.15 μg/g for both species). Concentrations of selenium (Se), and Se-to-Hg molar ratio, were also not correlated to breeding success. Although blood levels of 3.0 μg/g have been considered as a threshold of adverse effects in birds, even leading to severe effects, we detected no population-level reproductive effects, despite ~25% of the adult tits being above this level. Future work should investigate different locations in the mining district, different life-stages of the birds, and a wider variety of species. The hypothesis that bird populations can evolve resistance to Hg in contaminated areas should also be examined further.
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Affiliation(s)
- Tongping Su
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China; Key Laboratory of Beibu Gulf Environment Change and Resources Use, Ministry of Education, Nanning Normal University, Nanning, China
| | - Chao He
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Aiwu Jiang
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
| | - Eben Goodale
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, China.
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
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Dzielski SA, Razavi NR, Twining CW, Cleckner LB, Rohwer VG. Reconstructing avian mercury concentrations through time using museum specimens from New York State. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1802-1814. [PMID: 31729602 DOI: 10.1007/s10646-019-02123-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/04/2019] [Indexed: 06/10/2023]
Abstract
We examined how variation in MeHg concentrations through time is reflected in birds, a taxon commonly used as a biological indicator of ecosystem health. Using museum specimens collected from 1880 to 2016, we measured feather MeHg concentrations in six species of birds that breed in New York State and have distinct dietary and habitat preferences. We predicted that MeHg concentrations in feathers would mirror Hg emission patterns in New York State and increase through time until 1980 then decrease thereafter in response to increased regulation of anthropogenic Hg emissions. We found that MeHg concentrations increased with δ15N, and that MeHg feather concentrations for some individuals from four of the six species examined exceeded concentrations known to cause negative sublethal effects in birds. In contrast to our prediction, MeHg concentrations in feathers did not parallel global or local Hg emissions through time and varied by species, even after controlling for possible changes in diet and habitat. MeHg concentrations varied substantially within species and individual specimens, suggesting that high within-individual variation in feather MeHg concentrations caused by spatiotemporal variation in molt, environmental Hg exposure, or mobility decoupling Hg uptake from breeding sites, may obscure trends in MeHg through time. Our study provides a unique assessment of feather MeHg in six species not typically analyzed using this retrospective approach.
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Affiliation(s)
- Sarah A Dzielski
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14850, USA.
- Department of Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA.
- Cornell University Museum of Vertebrates, 159 Sapsucker Woods Road, Ithaca, NY, 14850, USA.
| | - N Roxanna Razavi
- Department of Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
- Finger Lakes Institute, Hobart and William Smith Colleges, Geneva, NY, 14556, USA
| | - Cornelia W Twining
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14850, USA
- Max Planck Institute for Animal Behavior, 78315, Radolfzell, Germany
- Limnological Institute, University of Konstanz, 78464, Konstanz, Germany
| | - Lisa B Cleckner
- Finger Lakes Institute, Hobart and William Smith Colleges, Geneva, NY, 14556, USA
| | - Vanya G Rohwer
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14850, USA
- Cornell University Museum of Vertebrates, 159 Sapsucker Woods Road, Ithaca, NY, 14850, USA
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Rimmer CC, Lloyd JD, McFarland KP, Evers DC, Lane OP. Patterns of blood mercury variation in two long-distance migratory thrushes on Mount Mansfield, Vermont. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1174-1182. [PMID: 31520201 DOI: 10.1007/s10646-019-02104-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
We investigated mercury (Hg) blood concentrations in Bicknell's thrush (Catharus bicknelli) and Swainson's thrush (C. ustulatus), congeneric long-distance migratory songbirds, from 2000-2017 at a montane forest site in north-central Vermont. We analyzed variation in blood Hg of both species using mixed-effects models, incorporating atmospheric wet Hg deposition data from a nearby sampling location. Although Hg deposition varied among years and seasonally, we detected no temporal trend in either atmospheric deposition or blood Hg, nor evidence of a relationship between the two. Sampling date had the strongest effect on blood Hg concentration, which declined seasonally, followed by age and sex of the individual. The data did not support an effect of species. We believe that the absence of a clear relationship between local atmospheric deposition and thrush blood Hg concentrations suggests that Hg cycling dynamics, mechanisms of transfer, and timing of uptake by montane forest biota are complex and poorly understood. The blood Hg concentrations of ~0.07-0.1 μg/g we documented in Bicknell's and Swainson's thrush are below those found to negatively impact physiological or reproductive endpoints in other invertivorous terrestrial passerines. To better evaluate the validity of Bicknell's thrush as a bioindicator of MeHg availability in montane forest ecosystems, we recommend (1) effects-based investigations, (2) a more robust understanding of Hg and MeHg cycling, (3) more clear geospatial and temporal links between Hg deposition and biotic uptake, and (4) more thorough documentation of Hg burdens across the species' annual cycle.
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Affiliation(s)
| | - John D Lloyd
- Vermont Center for Ecostudies, P.O. Box 420, Norwich, VT, 05055, USA
- American Wind Wildlife Institute, 1990 K Street NW, Suite 620, Washington, DC, 20006, USA
| | - Kent P McFarland
- Vermont Center for Ecostudies, P.O. Box 420, Norwich, VT, 05055, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Oksana P Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
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6
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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 (LONDON, ENGLAND) 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] [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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Grieves LA, Bottini CLJ, Branfireun BA, Bernards MA, MacDougall-Shackleton SA, MacDougall-Shackleton EA. Food stress, but not experimental exposure to mercury, affects songbird preen oil composition. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:275-285. [PMID: 32036507 DOI: 10.1007/s10646-020-02171-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/28/2020] [Indexed: 06/10/2023]
Abstract
Mercury is a global pollutant and potent neurotoxic metal. Its most toxic and bioavailable form, methylmercury, can have both lethal and sublethal effects on wildlife. In birds, methylmercury exposure can disrupt behavior, hormones, the neuroendocrine system, and feather integrity. Lipid-rich tissues and secretions may be particularly susceptible to disruption by lipophilic contaminants such as methylmercury. One such substance is feather preen oil, a waxy secretion of the uropygial gland that serves multiple functions including feather maintenance, anti-parasitic defense, and chemical signaling. If methylmercury exposure alters preen oil composition, it could have cascading effects on feather quality, susceptibility to ectoparasites, and mate choice and other social behaviors. We investigated whether exposure to methylmercury, either alone or in association with other stressors, affects preen oil chemical composition. We used a two-factor design to expose adult song sparrows (Melospiza melodia) to an environmentally relevant dietary dose of methylmercury and/or to another stressor (unpredictable food supply) for eight weeks. The wax ester composition of preen oil changed significantly over the 8-week experimental period. This change was more pronounced in the unpredictable food treatment, regardless of dietary methylmercury. Contrary to our prediction, we found no main effect of methylmercury exposure on preen oil composition, nor did methylmercury interact with unpredictable food supply in predicting the magnitude of chemical shifts in preen oil. While it remains critical to study sublethal effects of methylmercury on wildlife, our findings suggest that the wax ester composition of preen oil is robust to environmentally relevant doses of this contaminant.
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Affiliation(s)
- L A Grieves
- Department of Biology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5B7, Canada.
| | - C L J Bottini
- Department of Biology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5B7, Canada
| | - B A Branfireun
- Department of Biology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5B7, Canada
| | - M A Bernards
- Department of Biology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5B7, Canada
| | - S A MacDougall-Shackleton
- Department of Psychology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5C2, Canada
| | - E A MacDougall-Shackleton
- Department of Biology, The University of Western Ontario, 1151 Richmond St., London, ON, N6A 5B7, Canada
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8
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Scheiber IBR, Weiß BM, de Jong ME, Braun A, van den Brink NW, Loonen MJJE, Millesi E, Komdeur J. Stress behaviour and physiology of developing Arctic barnacle goslings ( Branta leucopsis) is affected by legacy trace contaminants. Proc Biol Sci 2018; 285:20181866. [PMID: 30963902 PMCID: PMC6304058 DOI: 10.1098/rspb.2018.1866] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 11/12/2018] [Indexed: 11/23/2022] Open
Abstract
Natural populations are persistently exposed to environmental pollution, which may adversely impact animal physiology and behaviour and even compromise survival. Responding appropriately to any stressor ultimately might tip the scales for survival, as mistimed behaviour and inadequate physiological responses may be detrimental. Yet effects of legacy contamination on immediate physiological and behavioural stress coping abilities during acute stress are virtually unknown. Here, we assessed these effects in barnacle goslings ( Branta leucopsis) at a historical coal mine site in the Arctic. For three weeks we led human-imprinted goslings, collected from nests in unpolluted areas, to feed in an abandoned coal mining area, where they were exposed to trace metals. As control we led their siblings to feed on clean grounds. After submitting both groups to three well-established stress tests (group isolation, individual isolation, on-back restraint), control goslings behaved calmer and excreted lower levels of corticosterone metabolites. Thus, legacy contamination may decisively change stress physiology and behaviour in long-lived vertebrates exposed at a young age.
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Affiliation(s)
- Isabella B. R. Scheiber
- Behavioural and Physiological Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
- Department of Behavioural Biology, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Brigitte M. Weiß
- Behavioural Ecology Research Group, University of Leipzig, 04103 Leipzig, Germany
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Margje E. de Jong
- Arctic Centre, University of Groningen, 9718 CW Groningen, The Netherlands
| | - Anna Braun
- Behavioural and Physiological Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Nico W. van den Brink
- Department of Toxicology, Wageningen University, 6700 EA Wageningen, The Netherlands
| | | | - Eva Millesi
- Department of Behavioural Biology, Faculty of Life Sciences, University of Vienna, 1090 Vienna, Austria
| | - Jan Komdeur
- Behavioural and Physiological Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
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Whitney MC, Cristol DA. Impacts of Sublethal Mercury Exposure on Birds: A Detailed Review. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2018; 244:113-163. [PMID: 28710647 DOI: 10.1007/398_2017_4] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mercury is a ubiquitous environmental contaminant known to accumulate in, and negatively affect, fish-eating and oceanic bird species, and recently demonstrated to impact some terrestrial songbirds to a comparable extent. It can bioaccumulate to concentrations of >1 μg/g in tissues of prey organisms such as fish and insects. At high enough concentrations, exposure to mercury is lethal to birds. However, environmental exposures are usually far below the lethal concentrations established by dosing studies.The objective of this review is to better understand the effects of sublethal exposure to mercury in birds. We restricted our survey of the literature to studies with at least some exposures >5 μg/g. The majority of sublethal effects were subtle and some studies of similar endpoints reached different conclusions. Strong support exists in the literature for the conclusion that mercury exposure reduces reproductive output, compromises immune function, and causes avoidance of high-energy behaviors. For some endpoints, notably certain measures of reproductive success, endocrine and neurological function, and body condition, there is weak or contradictory evidence of adverse effects and further study is required. There was no evidence that environmentally relevant mercury exposure affects longevity, but several of the sublethal effects identified likely do result in fitness reductions that could adversely impact populations. Overall, 72% of field studies and 91% of laboratory studies found evidence of deleterious effects of mercury on some endpoint, and thus we can conclude that mercury is harmful to birds, and the many effects on reproduction indicate that bird population declines may already be resulting from environmental mercury pollution.
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Affiliation(s)
- Margaret C Whitney
- Department of Biology, Institute for Integrative Bird Behavior Studies, The College of William and Mary, Williamsburg, VA, 23187, USA
| | - Daniel A Cristol
- Department of Biology, Institute for Integrative Bird Behavior Studies, The College of William and Mary, Williamsburg, VA, 23187, USA.
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Santos CSA, Blondel L, Sotillo A, Müller W, Stienen EWM, Boeckx P, Soares AMVM, Monteiro MS, Loureiro S, de Neve L, Lens L. Offspring Hg exposure relates to parental feeding strategies in a generalist bird with strong individual foraging specialization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 601-602:1315-1323. [PMID: 28605850 DOI: 10.1016/j.scitotenv.2017.05.286] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/30/2017] [Accepted: 05/31/2017] [Indexed: 06/07/2023]
Abstract
Generalist species can potentially exploit a wide variety of resources, but at the individual level they often show a certain degree of foraging specialization. Specific foraging strategies, however, may increase exposure to environmental contaminants that can alter the cost-benefit balance of consuming particular food items. The Lesser Black-backed Gull (Larus fuscus) is known to opportunistically feed on a wide range of marine and terrestrial prey that differ in contaminant load, such as mercury (Hg) that strongly biomagnifies through the aquatic food web. The hypothesis tested in this study were: i) a predominant use of marine prey by females during egg-formation and by both parents during chick rearing increases the exposure to Hg during embryonic development and chick growth, and ii) this affects parental investment in clutch volume, chick growth and body condition. Total Hg burden and isotopic signatures of carbon (δ13C) and nitrogen (δ15N) were determined for eggs, down feathers, and primary feathers of L. fuscus chicks collected at a coastal colony in Belgium. As expected, eggs and feathers of chicks from parents with a stable isotope signature that suggested a predominantly marine diet had higher levels of Hg. The use of marine resources by females during the egg-formation period positively correlated to maternal investment in egg size, though entailing the cost of increased Hg-concentrations which in turn negatively affected clutch volume. Furthermore, it is shown that the use of chick down feathers is a suitable matrix to non-lethally estimate Hg concentrations in eggs. Contrary to our expectations, no relationship between Hg exposure and chick growth or chick body condition was found, which may be due the low concentrations found. We conclude that currently Hg contamination does not constitute a risk for development and condition of L. fuscus offspring at the levels currently observed at the Belgian coast.
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Affiliation(s)
- Cátia S A Santos
- Department of Biology, Terrestrial Ecology Unit, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium; Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal..
| | - Léa Blondel
- Redpath Museum, Biology Department, McGill University, 859 Sherbrooke, Montréal, QC H3A 0C4, Canada
| | - Alejandro Sotillo
- Department of Biology, Terrestrial Ecology Unit, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium; Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Wendt Müller
- Department of Biology - Behavioural Ecology and Ecophysiology Group, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, 2610, Antwerp, Wilrijk, Belgium
| | - Eric W M Stienen
- Research Institute for Nature and Forest (INBO), Kliniekstraat 25, 1070 Brussels, Belgium
| | - Pascal Boeckx
- Isotope Bioscience Laboratory (ISOFYS), Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Amadeu M V M Soares
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Marta S Monteiro
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Susana Loureiro
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Liesbeth de Neve
- Department of Biology, Terrestrial Ecology Unit, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Luc Lens
- Department of Biology, Terrestrial Ecology Unit, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
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11
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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. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 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] [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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