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Liu X, Wang Z, Niu X, Wang B, Wang C, Cao H, Zhang X. Methylmercury exposure and risk of wintering migratory birds in the Poyang Lake basin, China. ENVIRONMENTAL RESEARCH 2024; 261:119641. [PMID: 39053757 DOI: 10.1016/j.envres.2024.119641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 07/16/2024] [Accepted: 07/17/2024] [Indexed: 07/27/2024]
Abstract
Mercury (Hg), especially methylmercury (MeHg), is a pervasive contaminant that poses significant risks to birds occupying high trophic levels. However, we have little knowledge about the mercury exposure and its risks for birds in Poyang Lake basin, China. Therefore, during 2020-2021, we investigated MeHg concentrations in breast feathers of wintering migratory birds (n = 430 from 43 species belonging to 9 orders) in Poyang Lake Nanji Wetland and Jiangxi Nanfengmian National Nature Reserve, China. MeHg concentrations in breast feathers varied greatly by species, foraging guilds and taxonomic orders, among which the highest concentration was detected in great egret (8849 ± 5975 ng g-1 dw). Comparing with studies worldwide, high MeHg concentrations in feathers of Ardeidae from Pelecaniformes were found in this area. Moreover, herons migrating between northern and southern China had lower MeHg concentration than residents in southern China related to habitat Hg. Considering the applicability and sensitivity of the equations for the transformation of MeHg concentrations in feathers to blood-equivalent total Hg (THg) values, method CJ that the equation based on songbirds was used for the transformation of the songbirds and the equation based on seabirds for the others performed better than other three for risk assessment of bird Hg in this study. 23.1% of birds from Poyang Lake were at risk of Hg exposure based on the method CJ. Carnivorous birds from Pelecaniformes had the highest risk levels, with 37.2% categorized as no risk (≤200 ng g-1 ww), 48.9% as low risk (200-1000 ng g-1 ww), 11.1% as moderate risk (1000-3000 ng g-1 ww), 1.1% as high risk (3000-4000 ng g-1 ww), and 1.7% as severe risk (>4000 ng g-1 ww). These risks suggest long-term monitoring and further advanced studies about freshwater waterbirds Hg exposure is necessary.
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Affiliation(s)
- Xu Liu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhangwei Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xiang Niu
- Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, 100091, China.
| | - Bing Wang
- Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, 100091, China
| | - Chunjie Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Huabin Cao
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Xiaoshan Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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Bottini CLJ, Whiley RE, Branfireun BA, MacDougall-Shackleton SA. Effects of sublethal methylmercury and food stress on songbird energetic performance: metabolic rates, molt and feather quality. J Exp Biol 2024; 227:jeb246239. [PMID: 38856174 DOI: 10.1242/jeb.246239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 05/28/2024] [Indexed: 06/11/2024]
Abstract
Organisms regularly adjust their physiology and energy balance in response to predictable seasonal environmental changes. Stressors and contaminants have the potential to disrupt these critical seasonal transitions. No studies have investigated how simultaneous exposure to the ubiquitous toxin methylmercury (MeHg) and food stress affects birds' physiological performance across seasons. We quantified several aspects of energetic performance in song sparrows, Melospiza melodia, exposed or not to unpredictable food stress and MeHg in a 2×2 experimental design, over 3 months during the breeding season, followed by 3 months post-exposure. Birds exposed to food stress had reduced basal metabolic rate and non-significant higher factorial metabolic scope during the exposure period, and had a greater increase in lean mass throughout most of the experimental period. Birds exposed to MeHg had increased molt duration, and increased mass:length ratio of some of their primary feathers. Birds exposed to the combined food stress and MeHg treatment often had responses similar to the stress-only or MeHg-only exposure groups, suggesting these treatments affected physiological performance through different mechanisms and resulted in compensatory or independent effects. Because the MeHg and stress variables were selected in candidate models with a ΔAICc lower than 2 but the 95% confidence interval of these variables overlapped zero, we found weak support for MeHg effects on all measures except basal metabolic rate, and for food stress effects on maximum metabolic rate, factorial metabolic scope and feather mass:length ratio. This suggests that MeHg and food stress effects on these measures are statistically identified but not simple and/or were too weak to be detected via linear regression. Overall, combined exposure to ecologically relevant MeHg and unpredictable food stress during the breeding season does not appear to induce extra energetic costs for songbirds in the post-exposure period. However, MeHg effects on molt duration could carry over across multiple annual cycle stages.
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Affiliation(s)
- Claire L J Bottini
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Rebecca E Whiley
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Brian A Branfireun
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Scott A MacDougall-Shackleton
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
- The University of Western Ontario, Department of Psychology, 1151 Richmond St., London, ON, N6A 5C2, Canada
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Ma Y, Choi CY, Shang L, Klaassen M, Ma Z, Chang Q, Jaspers VLB, Bai Q, He T, Leung KKS, Hassell CJ, Jessop R, Gibson L. Mercury contamination is an invisible threat to declining migratory shorebirds along the East Asian-Australasian Flyway. Commun Biol 2024; 7:585. [PMID: 38755288 PMCID: PMC11098816 DOI: 10.1038/s42003-024-06254-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 04/26/2024] [Indexed: 05/18/2024] Open
Abstract
Exposure to pollutants is a potentially crucial but overlooked driver of population declines in shorebirds along the East Asian-Australasian Flyway. We combined knowledge of moult strategy and life history with a standardised sampling protocol to assess mercury (Hg) contamination in 984 individuals across 33 migratory shorebird species on an intercontinental scale. Over one-third of the samples exceeded toxicity benchmarks. Feather Hg was best explained by moulting region, while habitat preference (coastal obligate vs. non-coastal obligate), the proportion of invertebrates in the diet and foraging stratum (foraging mostly on the surface vs. at depth) also contributed, but were less pronounced. Feather Hg was substantially higher in South China (Mai Po and Leizhou), Australia and the Yellow Sea than in temperate and Arctic breeding ranges. Non-coastal obligate species (Tringa genus) frequently encountered in freshwater habitats were at the highest risk. It is important to continue and expand biomonitoring research to assess how other pollutants might impact shorebirds.
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Affiliation(s)
- Yanju Ma
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, 541006, Guangxi, China
- Guangxi Key Laboratory of Rare and Endangered Animal Ecology, College of Life Sciences, Guangxi Normal University, Guilin, 541006, Guangxi, China
| | - Chi-Yeung Choi
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China.
- Environmental Research Center, Duke Kunshan University, Kunshan, 215316, Jiangsu, China.
| | - Lihai Shang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, Guizhou, China
| | - Marcel Klaassen
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
| | - Zhijun Ma
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Coastal Ecosystems Research Station of the Yangtze River Estuary, Institute of Biodiversity Science, School of Life Sciences, Fudan University, Shanghai, 200433, China
| | - Qing Chang
- Nanjing Normal University, Nanjing, 210024, Jiangsu, China
| | - Veerle L B Jaspers
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Qingquan Bai
- Dandong Forestry and Grassland Development Service Center, Dandong, 118000, Liaoning, China
| | - Tao He
- Zhanjiang Mangrove National Nature Reserve Bureau, Zhangjiang, Guangdong, 524000, China
| | - Katherine K-S Leung
- Hong Kong Waterbirds Ringing Group, Mai Po Nature Reserve, Mai Po, Hong Kong, China
| | - Chris J Hassell
- Australian Wader Studies Group, Curtin, ACT, 2605, Australia
| | - Roz Jessop
- Victorian Wader Study Group, Thornbury, VIC, 3071, Australia
| | - Luke Gibson
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China.
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Di Liberto JF, Griffith SC, Hall CJ, Mendelsohn AS, Swaddle JP. Exposure to Sublethal Concentrations of Lead (Pb) Affects Ecologically Relevant Behaviors in House Sparrows (Passer domesticus). ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2024; 86:199-216. [PMID: 38598146 PMCID: PMC11032286 DOI: 10.1007/s00244-024-01062-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 03/12/2024] [Indexed: 04/11/2024]
Abstract
Global contamination of environments with lead (Pb) poses threats to many ecosystems and populations. While exposure to Pb is toxic at high concentrations, recent literature has shown that lower concentrations can also cause sublethal, deleterious effects. However, there remains relatively little causal investigation of how exposure to lower concentrations of environmental Pb affects ecologically important behaviors. Behaviors often represent first-line responses of an organism and its internal physiological, molecular, and genetic responses to a changing environment. Hence, better understanding how behaviors are influenced by pollutants such as Pb generates crucial information on how species are coping with the effects of pollution more broadly. To better understand the effects of sublethal Pb on behavior, we chronically exposed adult wild-caught, captive house sparrows (Passer domesticus) to Pb-exposed drinking water and quantified a suite of behavioral outcomes: takeoff flight performance, activity in a novel environment, and in-hand struggling and breathing rate while being handled by an experimenter. Compared to controls (un-exposed drinking water), sparrows exposed to environmentally relevant concentrations of Pb exhibited decreases in takeoff flight performance and reduced movements in a novel environment following 9-10 weeks of exposure. We interpret this suite of results to be consistent with Pb influencing fundamental neuro-muscular abilities, making it more difficult for exposed birds to mount faster movements and activities. It is likely that suppression of takeoff flight and reduced movements would increase the predation risk of similar birds in the wild; hence, we also conclude that the effects we observed could influence fitness outcomes for individuals and populations altering ecological interactions within more naturalistic settings.
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Affiliation(s)
- Joseph F Di Liberto
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, USA.
- Department of Biology, William & Mary, Williamsburg, VA, USA.
| | - Simon C Griffith
- School of Natural Sciences, Macquarie University, Sydney, NSW, Australia
| | - Cara J Hall
- Department of Biology, William & Mary, Williamsburg, VA, USA
| | | | - John P Swaddle
- Department of Biology, William & Mary, Williamsburg, VA, USA
- Institute for Integrative Conservation, William & Mary, Williamsburg, VA, USA
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Ross M, Corimanya JL, Kaplan R, Kilgour DAV, Linkous CR, Guindre-Parker S. Elevated lead (Pb) in urban European starling (Sturnus vulgaris) feathers is not correlated to physiology or behavior. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168932. [PMID: 38048995 DOI: 10.1016/j.scitotenv.2023.168932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/16/2023] [Accepted: 11/25/2023] [Indexed: 12/06/2023]
Abstract
Urbanization is rapidly changing the environment and creating new challenges in the lives of animals across the globe. Anthropogenic contaminants-like heavy metals-can persist within the environment for prolonged periods of time and present a widespread problem for those living near contaminated areas. Lead (Pb) was a commonly used heavy metal that continues to threaten the health of all organisms despite being phased out, especially in urban areas where historical use was more common. In this study, a common urban-adapter, the European starling (Sturnus vulgaris), was trapped to explore whether feather Pb burden is greater in birds from urban habitats than rural habitats, as well as whether Pb burdens were correlated with behavior, physiology, and feather development. Across four sites (two rural and two urban), soil Pb concentrations were measured and 197 free-living starlings were captured to measure feather Pb concentrations. Using linear mixed models, this study found that urban starling nestlings had elevated feather Pb burdens compared to rural nestlings. In contrast, there was no correlation between Pb and urbanization in adult birds whose exposure to Pb may reflect a larger spatial range compared to nestlings. For both nestlings and adults, feather Pb was uncorrelated to corticosterone, testosterone, aggressive behavior, or feather growth rates. These findings suggest that starlings may be a useful biomonitoring tool to detect Pb in the local environment, however, the age and spatial range of birds is a critical consideration in applying this tool. Further work is needed to understand the intricate relationship between heavy metals, behavior, morphological development, and physiology in free-living organisms.
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Affiliation(s)
- Michelle Ross
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA; Department of Biological Sciences, Brock University, St. Catharines, ON, Canada
| | - Joanna L Corimanya
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA
| | - Rachel Kaplan
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Denyelle A V Kilgour
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA; Department of Biology, Tufts University, Medford, MA, USA
| | - Courtney R Linkous
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Sarah Guindre-Parker
- Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA, USA.
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Poliserpi MB, Brodeur JC. Behavioral and physiological changes in the passerine Agelaioides badius following the ingestion of coated seeds with imidacloprid in a 30-day experiment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167078. [PMID: 37717765 DOI: 10.1016/j.scitotenv.2023.167078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 09/05/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
The wide use of neonicotinoid seed treatment represents a hazard for farmland birds that feed on treated seeds. This study aimed to characterize the long-term effects of the neonicotinoid imidacloprid (IMI) in the passerine grayish baywing (Agelaioides badius). The birds were fed ad libitum for 32 days only with seeds treated with 53.1 (Low, 11 % of LD50) and 514 (High, (112 % of LD50) mg IMI/kg seed; these concentrations representing respectively, 1.8 and 17.1 % of 3 g IMI/kg, an average application rate used to treat crop seeds in Argentina. The effects exerted by IMI on birds were evaluated at behavioral, physiological, hematological, genotoxic, and biochemical levels. No differences in food consumption were observed between Control and Low treatments birds, indicating a lack of aversion to treated seeds. High treatment birds only decreased their food consumption by 20 % in the first 3 days of exposure. Birds from High treatment experienced an early loss of body weight, reduction in their mobility, lack of response to threats (i.e., predator call and approaching person), and altered their use of the cage. On the contrary, birds from Low treatment experienced a delay in the onset of effects like reduction in mobility, lack of response to threats, and a tendency to reduce their body weight. At the end of exposure, glutathione S transferase activity in the plasma of treated birds decreased, and cholinesterase activity increased in the liver of treated birds. This study highlights that consumption equivalent to 1.8 % of the daily diet of baywings as IMI-treated seeds, is sufficient to generate behavioral and physiological alterations and death. In the wild, these effects may have ecological consequences, by impairing the survival of birds, representing a risk to farmland bird populations.
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Affiliation(s)
- Maria Belen Poliserpi
- Instituto de Recursos Biológicos, Centro de Investigaciones de Recursos Naturales (CIRN), Instituto Nacional de Tecnología Agropecuaria (INTA), 1686 Hurlingham, Buenos Aires, Argentina.
| | - Julie Celine Brodeur
- Instituto de Recursos Biológicos, Centro de Investigaciones de Recursos Naturales (CIRN), Instituto Nacional de Tecnología Agropecuaria (INTA), 1686 Hurlingham, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
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Supekar SC, Gramapurohit NP. Does atrazine induce changes in predator recognition, growth, morphology, and metamorphic traits of larval skipper frogs (Euphlyctis cyanophlyctis)? JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:125-137. [PMID: 36245429 DOI: 10.1002/jez.2661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/20/2022] [Accepted: 09/16/2022] [Indexed: 11/07/2022]
Abstract
Atrazine, an info disruptor, interferes with the olfaction of aquatic organisms by impairing the chemosensory system. Consequently, it affects behavior, physiology, and growth increases mortality and infections, and suppresses the immune system of aquatic animals. In this study, we wanted to determine the sensitivity of larval Euphlyctis cyanophlyctis to different concentrations of atrazine by assessing their antipredator behavior, growth, morphology, and metamorphic traits. The results indicate that exposure to atrazine did not affect the survival of tadpoles. However, it caused retarded growth at higher concentrations. Interestingly, the antipredator behavior of tadpoles toward conspecific alarm cues decreased in a dose-dependent manner with an increase in the concentration of atrazine. Tadpoles exposed to low concentrations of atrazine had deeper, wider bodies and tails while those exposed to higher concentrations had shallower and narrower bodies with shallower tail muscles. However, at low and moderate concentrations atrazine did not affect size at metamorphosis, it extended the larval duration at higher concentrations.
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Li C, Luo K, Shao Y, Xu X, Chen Z, Liang T, Xu Z, Dong X, Wang H, Qiu G. Total and methylmercury concentrations in nocturnal migratory birds passing through Mount Ailao, Southwest China. ENVIRONMENTAL RESEARCH 2022; 215:114373. [PMID: 36165871 DOI: 10.1016/j.envres.2022.114373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
Despite growing concerns over mercury (Hg) accumulation in birds in recent decades, little is known about Hg exposure in nocturnal migratory birds. Here, total mercury (THg) and methylmercury (MeHg) were detected in the feathers of nocturnal migratory birds (n = 286, belonging to 46 species) passing through Mount Ailao in Southwest China. The stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were also determined to clarify the effects of trophic position, foraging guild, and foraging behavior on Hg bioaccumulation. Our results show that the THg and MeHg concentrations varied by two orders of magnitude among all nocturnal migratory birds investigated, with the lowest values (THg: 0.056 mg kg-1; MeHg: 0.038 mg kg-1) in the Asian koel (Eudynamys scolopaceus) and the highest (THg: 12 mg kg-1; MeHg: 7.8 mg kg-1) in the hair-crested drongo (Dicrurus hottentottus). Waterbirds showed higher δ15N values and higher THg and MeHg concentrations than songbirds, and the Hg concentrations in piscivorous species were significantly higher than those in herbivores, omnivores, and insectivores. Significant effects of foraging guilds (Kruskal-Wallis one-way ANOVA, p < 0.001) and foraging behaviors (Kruskal-Wallis one-way ANOVA, p < 0.001) on the Hg concentrations in migratory bird feathers were detected. A risk assessment indicated that approximately 7.0% of individuals were at moderate (2.4-5.0 mg kg-1) to high (>5.0 mg kg-1) risk of Hg exposure, and were therefore vulnerable to adverse physiological and behavioral effects. A long-term monitoring campaign during the migratory period is highly recommended to better understand the bioaccumulation of Hg in these nocturnal migratory bird populations over time.
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Affiliation(s)
- Chan Li
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Kang Luo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuxiao Shao
- School of Geography and Environmental Science, Guizhou Normal University, Guiyang, 550001, China
| | - Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhuo Chen
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China.
| | - Tao Liang
- Zhenyuan Management and Protection Bureau of Ailao Mountain National Nature Reserve, Zhenyuan, 666500, China
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xian Dong
- School of Chemistry and Materials Science, Guizhou Normal University, Guiyang, 550001, China
| | - Hongdong Wang
- Zhenyuan Management and Protection Bureau of Ailao Mountain National Nature Reserve, Zhenyuan, 666500, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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Bottini CLJ, Whiley RE, Branfireun BA, MacDougall-Shackleton SA. Effects of methylmercury and food stress on migratory activity in song sparrows, Melospiza melodia. Horm Behav 2022; 146:105261. [PMID: 36126358 DOI: 10.1016/j.yhbeh.2022.105261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 09/01/2022] [Accepted: 09/03/2022] [Indexed: 11/25/2022]
Abstract
Avian migration is a challenging life stage susceptible to the adverse effects of stressors, including contaminants like methylmercury (MeHg). Although birds often experience stressors and contaminants concurrently in the wild, no study to date has investigated how simultaneous exposure to MeHg and food stress affects migratory behavior. Our objectives were to determine if MeHg or food stress exposure during summer, alone or combined, has carry-over effects on autumn migratory activity, and if hormone levels (corticosterone, thyroxine) and body condition were related to these effects. We tested how exposure to dietary MeHg and/or food stress (unpredictable temporary food removal) affected migratory behavior in captive song sparrows, Melospiza melodia. Nocturnal activity was influenced by a 3-way interaction between MeHg × stress × nights of the study, indicating that activity changed over time in different ways depending on prior treatments. Thyroxine was not affected by treatment or sampling date. During the migratory season, fecal corticosterone metabolite concentrations increased in birds co-exposed to MeHg and food stress compared to controls, suggesting an additive carry-over effect. As well, during the period of behavioral recording, body condition increased with time in unstressed birds, but not in stressed birds. Fecal corticosterone metabolite concentrations were positively correlated to duration of nocturnal activity, but thyroxine levels and body condition were not. The differences in nocturnal activity between groups suggest that food stress and MeHg exposure on breeding grounds could have direct and indirect carry-over effects that have the potential to affect the fall migration journey.
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Affiliation(s)
- Claire L J Bottini
- University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada.
| | - Rebecca E Whiley
- University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada
| | - Brian A Branfireun
- University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada
| | - Scott A MacDougall-Shackleton
- Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada; University of Western Ontario, Department of Psychology, 1151 Richmond St., London, Ontario N6A 5C2, Canada
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10
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Ma Y, Choi CY, Thomas A, Gibson L. Review of contaminant levels and effects in shorebirds: Knowledge gaps and conservation priorities. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 242:113868. [PMID: 35863215 DOI: 10.1016/j.ecoenv.2022.113868] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 06/20/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Environmental pollution has emerged as a major threat to bird populations. Many shorebird populations are declining, although contamination has been documented in some shorebirds, evidence of negative impacts is sparse and this important topic remains understudied. To guide future research and develop effective conservation strategies, we carried out a comprehensive review of environmental pollutants and their consequences on shorebirds. In total, we found 93 relevant articles which examined pollutant contamination in ~37% (79 of 215) of all shorebird species, mostly from the Charadriidae and Scolopacidae families. Studies were geographically biased: the majority were conducted in American flyways, while only 1 was found from Australasia and few were conducted in Asian flyways. The main geographic gap for research includes East Africa, South Asia and Siberian Arctic. The most well-documented pollutants included mercury (Hg, 37 studies), cadmium (33), and lead (Pb, 28); less well studied pollutants were barium (1), calcium (1), strontium (1), dicofols (1), and other newly emerging contaminants, such as plastic debris/microplastics (4) and antibiotics resistance (2). Several pollutants have caused considerable concerns in shorebirds, including embryotoxicity caused by PCBs at non-optimum temperature (laboratory experiments); reduced reproduction performance linked to maternal Hg and paternal Pb (field evidence); and reduced refueling and flight performance related to oil contamination (both field and laboratory evidence). Our results confirm that an in-depth understanding of the local, regional and global factors that influence population trends of shorebirds in light of increasing pollution threats is essential for accurate and effective management and conservation strategies.
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Affiliation(s)
- Yanju Ma
- School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Chi-Yeung Choi
- School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Alex Thomas
- School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Luke Gibson
- School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
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Lancaster ST, Peniche G, Alzahrani A, Blanz M, Newton J, Taggart MA, Corns WT, Krupp EM, Feldmann J. Mercury speciation in Scottish raptors reveals high proportions of inorganic mercury in Scottish golden eagles (Aquila chrysaetos): Potential occurrence of mercury selenide nanoparticles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 829:154557. [PMID: 35302012 DOI: 10.1016/j.scitotenv.2022.154557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/31/2022] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
Knowledge of the uptake and fate of mercury (Hg) compounds in biota is important in understanding the global cycling of Hg and its transfer pathways through food chains. In this study, we analysed total mercury (T-Hg) and methylmercury (MeHg) concentrations in 117 livers of Scottish birds of prey that were found across Scotland and submitted for post-mortem examination through the Raptor Health Scotland project between 2009 and 2019. Statistical comparisons focussed on six species (barn owl, Tyto alba; Eurasian common buzzard, Buteo buteo; golden eagle, Aquila chrysaetos; hen harrier, Circus cyaneus; Eurasian sparrowhawk, Accipiter nisus; and tawny owl, Strix aluco) and showed that golden eagles had a statistically lower fraction of MeHg compared to other raptor species. Further investigation using stable carbon and stable nitrogen isotope ratio measurements carried out for the golden eagles (n = 15) indicated that the increased presence of inorganic mercury (iHg) correlated with a marine influence on the primarily terrestrial diet. Additional bioimaging (n = 1) with laser ablation - inductively coupled plasma - mass spectrometry indicated the co-location of Hg and selenium (Se) within the liver tissue and transmission electron microscopy showed evidence of nanoparticles within the range of 10-20 nm. Further analysis using single particle - inductively coupled plasma - mass spectrometry (n = 4) confirmed the presence of Hg nanoparticles. Together, the evidence suggests the presence of mercury selenide (HgSe) nanoparticles in the liver of some golden eagles that, to our knowledge, has never been directly observed in terrestrial birds of prey. This study points to two alternative hypotheses: these golden eagles may be efficient at breaking down MeHg and form HgSe nanoparticles as a detoxification mechanism (as previously observed in cetaceans), or some golden eagles with elevated iHg may have accumulated these nanoparticles by foraging on stranded cetaceans or seabirds.
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Affiliation(s)
- Shaun T Lancaster
- Trace Element Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, UK; PS Analytical, Crayfields Industrial Estate, Main Road, Orpington, Kent BR5 3HP, UK; Department of General, Analytical and Physical Chemistry, Chair of General and Analytical Chemistry, Montanuniversität Leoben, Franz Josef-Strasse 18, 8700 Leoben, Austria.
| | - Gabriela Peniche
- The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Campus, Midlothian, Edinburgh, EH25 9RG, UK
| | - Ali Alzahrani
- Trace Element Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, UK
| | - Magdalena Blanz
- Trace Element Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, UK; Archaeology Institute, University of the Highlands and Islands, Orkney College UHI, Kirkwall, Orkney, KW15 1LX, Scotland, UK
| | - Jason Newton
- National Environmental Isotope Facility, Scottish Universities Environmental Research Centre (SUERC), East Kilbride, G75 0QF, UK
| | - Mark A Taggart
- The Environmental Research Institute (ERI), University of Highlands and Islands, Castle St, Thurso KW14 7JD, UK
| | - Warren T Corns
- PS Analytical, Crayfields Industrial Estate, Main Road, Orpington, Kent BR5 3HP, UK
| | - Eva M Krupp
- Trace Element Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, UK
| | - Jörg Feldmann
- Trace Element Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, Meston Walk, University of Aberdeen, Aberdeen AB24 3UE, UK; TESLA - Analytical Chemistry, Institute of Chemistry, University of Graz, Universitaetsplatz 1, 8010 Graz, Austria
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12
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Short-term mercury exposure disrupts muscular and hepatic lipid metabolism in a migrant songbird. Sci Rep 2022; 12:11470. [PMID: 35794224 PMCID: PMC9259677 DOI: 10.1038/s41598-022-15680-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/28/2022] [Indexed: 11/18/2022] Open
Abstract
Methylmercury (MeHg) is a global pollutant that can cause metabolic disruptions in animals and thereby potentially compromise the energetic capacity of birds for long-distance migration, but its effects on avian lipid metabolism pathways that support endurance flight and stopover refueling have never been studied. We tested the effects of short-term (14-d), environmentally relevant (0.5 ppm) dietary MeHg exposure on lipid metabolism markers in the pectoralis and livers of yellow-rumped warblers (Setophaga coronata) that were found in a previous study to have poorer flight endurance in a wind tunnel than untreated conspecifics. Compared to controls, MeHg-exposed birds displayed lower muscle aerobic and fatty acid oxidation capacity, but similar muscle glycolytic capacity, fatty acid transporter expression, and PPAR expression. Livers of exposed birds indicated elevated energy costs, lower fatty acid uptake capacity, and lower PPAR-γ expression. The lower muscle oxidative enzyme capacity of exposed birds likely contributed to their weaker endurance in the prior study, while the metabolic changes observed in the liver have potential to inhibit lipogenesis and stopover refueling. Our findings provide concerning evidence that fatty acid catabolism, synthesis, and storage pathways in birds can be dysregulated by only brief exposure to MeHg, with potentially significant consequences for migratory performance.
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13
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Bottini CLJ, MacDougall-Shackleton SA, Branfireun BA, Hobson KA. Feathers accurately reflect blood mercury at time of feather growth in a songbird. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 775:145739. [PMID: 33621875 DOI: 10.1016/j.scitotenv.2021.145739] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/04/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
Methylmercury (MeHg) is a globally distributed pollutant that can negatively affect wildlife. Bird feathers are often used as a monitoring tool of contaminant exposure, but variability in total mercury (THg) content in flight feathers has raised concerns over their utility. The objective of this study was to quantify blood and feather THg depuration through the progression of primary feather molt in order to clarify the relationship between blood and feather mercury concentration, and test the reliability of feather THg measurements as a monitoring tool in wild songbirds. Song sparrows (Melospiza melodia) were experimentally exposed to dietary MeHg and their blood and primary feather THg concentrations were measured during exposure and post-exposure periods of three months each. A rapid decrease in feather and blood THg concentration through molt progression was observed. Primary feather THg content was higher in feathers grown during the MeHg exposure period compared to those grown during the post-exposure period. Primary feather THg concentration was highly correlated with blood THg measured at the time of feather growth (R = 0.98), indicating that, although THg concentration is variable among flight feathers, this reflects temporally sequential molting patterns and declining blood concentration during depuration. Primary flight feathers thus provide an accurate and useful tool for estimating the mercury burden of birds at the time a chosen feather was grown, and have the potential to be an effective and reliable biomonitoring tool for species with well-characterized molt patterns.
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Affiliation(s)
- Claire L J Bottini
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada.
| | - Scott A MacDougall-Shackleton
- Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada; The University of Western Ontario, Department of Psychology, 1151 Richmond St., London, Ontario, N6A 5C2, Canada
| | - Brian A Branfireun
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Centre for Environment and Sustainability, University of Western Ontario, London, Ontario, Canada
| | - Keith A Hobson
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, Ontario N6A 5B7, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada
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14
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Adams EM, Williams KA, Olsen BJ, Evers DC. Mercury exposure in migrating songbirds: correlations with physical condition. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1240-1253. [PMID: 32189148 DOI: 10.1007/s10646-020-02190-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/28/2020] [Indexed: 06/10/2023]
Abstract
Many migratory songbirds are at high risk of methylmercury (MeHg) exposure due to their trophic position and foraging in and around wetland habitats. Methylmercury has the potential to alter migratory behaviors and physiology via neurological impairment or reduced flight performance and can be remobilized from songbird muscle tissue during migration, increasing the risk of acute MeHg exposure. To document MeHg exposure and its relationship with physical condition in migratory songbirds, we sampled passerine blood and feathers at a migration stopover site on Key Biscayne, FL during fall and spring from 2009 to 2012. We found evidence that spring blood total mercury (THg) concentrations decreased throughout the day and that fall feather THg concentrations changed over the migratory season. Total mercury exposure was marginally correlated with migratory fat stores and related to changes in pectoral muscle thickness by time of day. These patterns suggest that environmentally relevant levels of THg are related to, and may be influencing, the physical condition of free-living migrating songbirds. Further research and monitoring during the migratory period will be important to elucidate exposure risk across multiple species and assess the potential for effects during this complex period of the annual cycle.
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Affiliation(s)
- Evan M Adams
- School of Biology and Ecology, Climate Change Institute, University of Maine, Chadbourne Hall, Orono, ME, USA.
- Biodiversity Research Institute, 276 Canco Rd., Portland, ME, 04103, USA.
| | - Kathryn A Williams
- Biodiversity Research Institute, 276 Canco Rd., Portland, ME, 04103, USA
| | - Brian J Olsen
- School of Biology and Ecology, Climate Change Institute, University of Maine, Chadbourne Hall, Orono, ME, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Rd., Portland, ME, 04103, USA
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15
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Seewagen CL. The threat of global mercury pollution to bird migration: potential mechanisms and current evidence. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1254-1267. [PMID: 30159636 DOI: 10.1007/s10646-018-1971-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Mercury is a global pollutant that has been widely shown to adversely affect reproduction and other endpoints related to fitness and health in birds, but almost nothing is known about its effects on migration relative to other life cycle processes. Here I consider the physiological and histological effects that mercury is known to have on non-migrating birds and non-avian vertebrates to identify potential mechanisms by which mercury might hinder migration performance. I posit that the broad ability of mercury to inactivate enzymes and compromise the function of other proteins is a single mechanism by which mercury has strong potential to disrupt many of the physiological processes that make long-distance migration possible. In just this way alone, there is reason to expect mercury to interfere with navigation, flight endurance, oxidative balance, and stopover refueling. Navigation and flight could be further affected by neurotoxic effects of mercury on the brain regions that process geomagnetic information from the visual system and control biomechanics, respectively. Interference with photochemical reactions in the retina and decreases in scotopic vision sensitivity caused by mercury also have the potential to disrupt visual-based magnetic navigation. Finally, migration performance and possibly survival might be limited by the immunosuppressive effects of mercury on birds at a time when exposure to novel pathogens and parasites is great. I conclude that mercury pollution is likely to be further challenging what is already often the most difficult and perilous phase of a migratory bird's annual cycle, potentially contributing to global declines in migratory bird populations.
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Affiliation(s)
- Chad L Seewagen
- Great Hollow Nature Preserve & Ecological Research Center, 225 Route 37, New Fairfield, CT, USA.
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16
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Scoville SA, Varian-Ramos CW, Adkins GA, Swaddle JP, Saha MS, Cristol DA. Mercury delays cerebellar development in a model songbird species, the zebra finch. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1128-1137. [PMID: 32827288 DOI: 10.1007/s10646-020-02270-9] [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
Mercury exposure can disrupt development of the cerebellum, part of the brain essential for coordination of movement through a complex environment, including flight. In precocial birds, such as fowl, the cerebellum develops embryonically, and the chick is capable of leaving the nest within hours of hatching. However, most birds, including all songbirds, are altricial, and spend weeks in the nest between hatching and fledging. The objective of this study was to describe the normal development of the cerebellum in a model altricial songbird so as to determine the effect of exposure to mercury on cerebellar maturation. Adult zebra finch (Taeniopygia guttata) pairs were fed either a control diet, or a diet augmented with one of four treatment-levels of methylmercury (0.3-2.4 μg/g wet weight), and their offspring, the subjects of this study, were fed the same diet by parents. We documented, for the first time, the schedule of cerebellar development in an altricial bird, and compared stages of development among methylmercury-exposed groups. For all treatments of methylmercury, the age of completion of cellular migration was later than for control zebra finches, indicating a delay in cerebellar maturation. Displaced (heterotopic) Purkinje neurons, a pathology typical of methylmercury exposure in developing vertebrate brains, were more numerous in methylmercury-exposed birds, and persisted at least until the age of independence. Delays in maturation of the cerebellum could delay fledging in altricial bird species, with potential serious implications for the fitness of exposed individuals, as predation rates in the nest are often very high.
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Affiliation(s)
- Sheila A Scoville
- Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
| | - Claire W Varian-Ramos
- Department of Biology, William & Mary, Williamsburg, VA, 23185, USA
- Biology Department, Colorado State University - Pueblo, Pueblo, CO, 81001, USA
| | - G Alden Adkins
- Department of Biology, William & Mary, Williamsburg, VA, 23185, USA
- University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - John P Swaddle
- Department of Biology, William & Mary, Williamsburg, VA, 23185, USA
| | - Margaret S Saha
- Department of Biology, William & Mary, Williamsburg, VA, 23185, USA
| | - Daniel A Cristol
- Department of Biology, William & Mary, Williamsburg, VA, 23185, USA.
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17
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Perkins M, Lane OP, Evers DC, Sauer A, Adams EM, O'Driscoll NJ, Edmunds ST, Jackson AK, Hagelin JC, Trimble J, Sunderland EM. Historical patterns in mercury exposure for North American songbirds. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1161-1173. [PMID: 31161526 DOI: 10.1007/s10646-019-02054-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/09/2019] [Indexed: 06/09/2023]
Abstract
Methylmercury (MeHg) is a global environmental contaminant that poses significant risks to the health of humans, wildlife, and ecosystems. Assessing MeHg exposure in biota across the landscape and over time is vital for monitoring MeHg pollution and gauging the effectiveness of regulations intended to reduce new mercury (Hg) releases. We used MeHg concentrations measured in museum specimen feathers (collected between 1869 and 2014) and total Hg concentrations (as a proxy for MeHg) of feathers sampled from wild birds (collected between 2008 and 2017) to investigate temporal patterns in exposure over approximately 150 years for North American songbirds. For individual species, we found greater concentrations for samples collected post-2000 compared to those collected during historic times (pre-1900) for six of seven songbird species. Mean feather concentrations measured in samples collected post-2000 ranged between 1.9 and 17 times (mean 6.6) greater than historic specimens. The proportion of individual songbirds with feather concentrations that exceeded modeled toxicity benchmarks increased in samples collected after 1940. Only 2% of individual songbirds collected prior to 1940 had feather concentrations greater than 2.4 μg/g (a toxicity benchmark related to a 10% decrease in nest success) compared to 35% of individuals collected post-1940. Many species included in this study have a vulnerable or near-threatened conservation status, suggesting recovery actions are needed to address mercury pollution.
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Affiliation(s)
- Marie Perkins
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
| | - Oksana P Lane
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - David C Evers
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Amy Sauer
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Evan M Adams
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Nelson J O'Driscoll
- K. C. Irving Environmental Science Centre, Department of Earth and Environmental Sciences, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | | | - Allyson K Jackson
- Department of Environmental Studies, Purchase College, SUNY, Purchase, NY, 10577, USA
| | - Julie C Hagelin
- Alaska Department of Fish and Game, Threatened, Endangered and Diversity Program, Fairbanks, AK, 99701, USA
| | - Jeremiah Trimble
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, 02138, USA
| | - Elsie M Sunderland
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
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18
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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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19
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Yamac E, Ozden M, Kirazli C, Malkoc S. Heavy-metal concentrations in feathers of cinereous vulture (Aegypius monachus L.) as an endangered species in Turkey. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:833-843. [PMID: 30415366 DOI: 10.1007/s11356-018-3649-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
The aim of this study is to find out the certain heavy-metal levels in the feathers of cinereous vulture (Aegypius monachus L.), which is a threatened species. The feathers of the cinereous vultures were collected from the breeding areas in Sündiken and Türkmenbaba Mountains. To avoid misleading results, vanes and calamuses of the rectrices were evaluated separately in terms of their As, Cd, Cr, Cu, Hg, Ni, Pb and Zn contents. ICP-OES was used to analyse the metal levels in feathers which belonged to 43 different individuals. All of the heavy-metal concentrations except for Cu were higher in vanes than in calamuses. The mean levels of Cd (0.254 ± 1.589 μg/g d.w. in the calamus and 0.334 ± 0.156 μg/g d.w. in the vane), Cr (6.536 ± 6.378 μg/g d.w. in the vane), Ni (11.886 ± 10.891 μg/g d.w. in the vane) and Pb (5.671 ± 3.884 μg/g d.w. in the vane) exceeded the threshold values for the birds. As a result, we recommend further studies to understand the effects of the heavy metals on the population of the species.
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Affiliation(s)
- Elif Yamac
- Department of Biology, Science Faculty, Eskişehir Technical University, Eskişehir, Turkey.
| | - Menekse Ozden
- Graduate School of Sciences, Anadolu University, Eskişehir, Turkey
| | - Cihangir Kirazli
- Department of Wildlife Ecology and Management, Abant İzzet Baysal University, Bolu, Turkey
| | - Semra Malkoc
- Porsuk Vocational School, Eskişehir Technical Universtiy, Eskişehir, Turkey
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20
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Ma Y, Perez CR, Branfireun BA, Guglielmo CG. Dietary exposure to methylmercury affects flight endurance in a migratory songbird. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 234:894-901. [PMID: 29253830 DOI: 10.1016/j.envpol.2017.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 12/01/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
Although there has been much speculation in the literature that methylmercury (MeHg) exposure can reduce songbird fitness, little is known about its effects on migration. Migrating songbirds typically make multiple flights, stopping to refuel for short periods between flights. How refueling at MeHg-contaminated stopover sites would contribute to MeHg bioaccumulation, and how such exposure could affect subsequent flight performance during migration has not been determined. In a dosing experiment we show that migratory yellow-rumped warblers (Setophaga coronata) rapidly accumulate dietary MeHg in blood, brain and muscle, liver and kidneys in just 1-2 weeks. We found that exposure to a 0.5 ppm diet did not affect vertical takeoff performance, but in 2-h wind tunnel flights, MeHg-treated warblers had a greater median number of strikes (landing or losing control) in the first 30 min, longer strike duration, and shorter flight duration. The number of strikes in the first 30 min of 0.5 ppm MeHg-exposed warblers was related to mercury concentration in blood in a sigmoid, dose-dependent fashion. Hyperphagic migratory songbirds may potentially bioaccumulate MeHg rapidly, which can lead to decreased migratory endurance flight performance.
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Affiliation(s)
- Yanju Ma
- Department of Biology, University of Western Ontario, London, Ontario, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada.
| | - Cristina R Perez
- Department of Agriculture, Nutrition and Veterinary Sciences, University of Nevada, Reno, NV 89557, USA
| | - Brian A Branfireun
- Department of Biology, University of Western Ontario, London, Ontario, Canada; Centre for Environment and Sustainability, University of Western Ontario, London, Ontario, Canada
| | - Christopher G Guglielmo
- Department of Biology, University of Western Ontario, London, Ontario, Canada; Advanced Facility for Avian Research, University of Western Ontario, London, Ontario, Canada
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21
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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: 42] [Impact Index Per Article: 7.0] [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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22
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Abeysinghe KS, Qiu G, Goodale E, Anderson CWN, Bishop K, Evers DC, Goodale MW, Hintelmann H, Liu S, Mammides C, Quan RC, Wang J, Wu P, Xu XH, Yang XD, Feng X. Mercury flow through an Asian rice-based food web. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 229:219-228. [PMID: 28599206 DOI: 10.1016/j.envpol.2017.05.067] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 06/07/2023]
Abstract
Mercury (Hg) is a globally-distributed pollutant, toxic to humans and animals. Emissions are particularly high in Asia, and the source of exposure for humans there may also be different from other regions, including rice as well as fish consumption, particularly in contaminated areas. Yet the threats Asian wildlife face in rice-based ecosystems are as yet unclear. We sought to understand how Hg flows through rice-based food webs in historic mining and non-mining regions of Guizhou, China. We measured total Hg (THg) and methylmercury (MeHg) in soil, rice, 38 animal species (27 for MeHg) spanning multiple trophic levels, and examined the relationship between stable isotopes and Hg concentrations. Our results confirm biomagnification of THg/MeHg, with a high trophic magnification slope. Invertivorous songbirds had concentrations of THg in their feathers that were 15x and 3x the concentration reported to significantly impair reproduction, at mining and non-mining sites, respectively. High concentrations in specialist rice consumers and in granivorous birds, the later as high as in piscivorous birds, suggest rice is a primary source of exposure. Spiders had the highest THg concentrations among invertebrates and may represent a vector through which Hg is passed to vertebrates, especially songbirds. Our findings suggest there could be significant population level health effects and consequent biodiversity loss in sensitive ecosystems, like agricultural wetlands, across Asia, and invertivorous songbirds would be good subjects for further studies investigating this possibility.
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Affiliation(s)
- Kasun S Abeysinghe
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; Guangxi Key Laboratory of Forest Ecology and Conservation (under state evaluation status), College of Forestry, Guangxi University, Nanning, Guangxi 530005, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Eben Goodale
- Guangxi Key Laboratory of Forest Ecology and Conservation (under state evaluation status), College of Forestry, Guangxi University, Nanning, Guangxi 530005, China.
| | - Christopher W N Anderson
- Soil and Earth Sciences, Institute of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand
| | - Kevin Bishop
- Department of Earth Sciences, Uppsala University, Villavägen, Uppsala 16, 752 36, Sweden; Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelmsväg 9, Uppsala, SE 75007, Sweden
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME 04103, United States
| | - Morgan W Goodale
- Biodiversity Research Institute, 276 Canco Road, Portland, ME 04103, United States
| | - Holger Hintelmann
- Trent University, Chemistry Department, 1600 West Bank Drive, Peterborough, Ontario K9J 7B8, Canada
| | - Shengjie Liu
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Christos Mammides
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China
| | - Rui-Chang Quan
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China
| | - Jin Wang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Pianpian Wu
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelmsväg 9, Uppsala, SE 75007, Sweden
| | - Xiao-Hang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-Dong Yang
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
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23
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Franceschini MD, Evers DC, Kenow KP, Meyer MW, Pokras M, Romero LM. Mercury correlates with altered corticosterone but not testosterone or estradiol concentrations in common loons. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 142:348-354. [PMID: 28437726 DOI: 10.1016/j.ecoenv.2017.04.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Revised: 03/17/2017] [Accepted: 04/14/2017] [Indexed: 06/07/2023]
Abstract
We investigated the relation between environmental mercury exposure and corticosterone concentrations in free-living adult common loons (Gavia immer). We determined blood and feather mercury concentrations and compared them to testosterone, estradiol, and stress-induced plasma corticosterone concentrations. Although neither testosterone nor estradiol correlated with Hg levels, there was a robust positive relation between blood Hg and stress-induced corticosterone concentrations in males, but not in females. The lack of an effect in females may have been due to overall less contamination in females. There were no significant correlations between feather Hg and stress-induced corticosterone in either sex. To help determine whether Hg had a causal effect on corticosterone, we investigated the impact of experimental Hg intake on the corticosterone stress response in captive juvenile loons. Juveniles were subjected to three different feeding regimes: 0, 0.4 and 1.2μg Hg (as MeHgCL)/g wet weight (ww) fish. We then measured baseline and 30min post-solitary confinement stressor corticosterone concentrations. The Hg fed chicks exhibited a decreased ability to mount a stress response. From these data, we conclude that Hg contamination does appear to alter the corticosterone response to stress, but not in a consistent predictable pattern. Regardless of the direction of change, however, exposure to mercury contamination and the resulting impact on the corticosterone stress response in common loons may substantially impact health, fitness and survival.
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Affiliation(s)
| | - David C Evers
- Biodiversity Research Institute, Portland, ME 04103, USA
| | - Kevin P Kenow
- US Geological Survey, Upper Midwest Environmental Sciences Center, La Crosse, WI 54603, USA
| | - Michael W Meyer
- Wisconsin Department of Natural Resources, Rhinelander, Wisconsin 54501, USA
| | - Mark Pokras
- Biodiversity Research Institute, Portland, ME 04103, USA; Wildlife Clinic, Cummings School of Veterinary Medicine, North Grafton, MA 01536, USA
| | - L Michael Romero
- Department of Biology, Tufts University, Medford, MA 02155, USA.
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24
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Wolf SE, Swaddle JP, Cristol DA, Buchser WJ. Methylmercury Exposure Reduces the Auditory Brainstem Response of Zebra Finches (Taeniopygia guttata ). J Assoc Res Otolaryngol 2017; 18:569-579. [PMID: 28361373 DOI: 10.1007/s10162-017-0619-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 03/02/2017] [Indexed: 12/11/2022] Open
Abstract
Mercury contamination from mining and fossil fuel combustion causes damage to humans and animals worldwide. Mercury exposure has been implicated in mammalian hearing impairment, but its effect on avian hearing is unknown. In this study, we examined whether lifetime dietary mercury exposure affected hearing in domestic zebra finches (Taeniopygia guttata) by studying their auditory brainstem responses (ABRs). Zebra finches exposed to mercury exhibited elevated hearing thresholds, decreased amplitudes, and longer latencies in the ABR, the first evidence of mercury-induced hearing impairment in birds. Birds are a more appropriate model for the human auditory spectrum than most mammals because of similarities in frequency discrimination, vocal learning, and communication behavior. When mercury is considered in combination with other anthropogenic stressors such as noise pollution and habitat alteration, the hearing impairments we document here could substantially degrade avian auditory communication in wild birds.
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Affiliation(s)
- Sarah E Wolf
- Biology Department, College of William & Mary, Williamsburg, VA, 23185, USA
| | - John P Swaddle
- Biology Department, College of William & Mary, Williamsburg, VA, 23185, USA
| | - Daniel A Cristol
- Biology Department, College of William & Mary, Williamsburg, VA, 23185, USA
| | - William J Buchser
- Biology Department, College of William & Mary, Williamsburg, VA, 23185, USA.
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25
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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] [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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26
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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. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:749-769. [PMID: 27093907 PMCID: PMC5365029 DOI: 10.1016/j.scitotenv.2016.03.071] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [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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27
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McHuron EA, Peterson SH, Ackerman JT, Melin SR, Harris JD, Costa DP. Effects of Age, Colony, and Sex on Mercury Concentrations in California Sea Lions. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:46-55. [PMID: 26259982 DOI: 10.1007/s00244-015-0201-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 07/27/2015] [Indexed: 06/04/2023]
Abstract
We measured total mercury (THg) concentrations in California sea lions (Zalophus californianus) and examined how concentrations varied with age class, colony, and sex. Because Hg exposure is primarily via diet, we used nitrogen (δ (15)N) and carbon (δ (13)C) stable isotopes to determine if intraspecific differences in THg concentrations could be explained by feeding ecology. Blood and hair were collected from 21 adult females and 57 juveniles from three colonies in central and southern California (San Nicolas, San Miguel, and Año Nuevo Islands). Total Hg concentrations ranged from 0.01 to 0.31 μg g(-1) wet weight (ww) in blood and 0.74 to 21.00 μg g(-1) dry weight (dw) in hair. Adult females had greater mean THg concentrations than juveniles in blood (0.15 vs. 0.03 μg(-1) ww) and hair (10.10 vs. 3.25 μg(-1) dw). Age class differences in THg concentrations did not appear to be driven by trophic level or habitat type because there were no differences in δ (15)N or δ (13)C values between adults and juveniles. Total Hg concentrations in adult females were 54 % (blood) and 24 % (hair) greater in females from San Miguel than females from San Nicolas Island, which may have been because sea lions from the two islands foraged in different areas. For juveniles, we detected some differences in THg concentrations with colony and sex, although these were likely due to sampling effects and not ecological differences. Overall, THg concentrations in California sea lions were within the range documented for other marine mammals and were generally below toxicity benchmarks for fish-eating wildlife.
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Affiliation(s)
- Elizabeth A McHuron
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, 100 Shaffer Road, Santa Cruz, CA, 95060, USA.
| | - Sarah H Peterson
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, 100 Shaffer Road, Santa Cruz, CA, 95060, USA
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, 800 Business Park Drive, Suite D, Dixon, CA, 95620, USA
| | - Sharon R Melin
- National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, WA, 98155, USA
| | - Jeffrey D Harris
- National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, WA, 98155, USA
| | - Daniel P Costa
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, 100 Shaffer Road, Santa Cruz, CA, 95060, USA
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28
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Kobiela ME, Cristol DA, Swaddle JP. Risk-taking behaviours in zebra finches affected by mercury exposure. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.02.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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