1
|
Parker MC, Fritts SR, Weaver SP, Meierhofer MB, Dutton J. Inter- and intraspecific variability of total mercury concentrations in bats of Texas (USA). ENVIRONMENTAL RESEARCH 2024; 259:119570. [PMID: 38971354 DOI: 10.1016/j.envres.2024.119570] [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: 04/09/2024] [Revised: 06/15/2024] [Accepted: 07/04/2024] [Indexed: 07/08/2024]
Abstract
Exposure to mercury (Hg) may cause deleterious health effects in wildlife, including bats. Texas produces more Hg pollution than any other state in the United States, yet only one study has examined Hg accumulation in bats. This study measured the concentration of total Hg (THg) in fur (n = 411) collected from ten bat species across 32 sites in eastern and central Texas, USA. Fur THg concentrations were compared among species, and when samples sizes were large enough, between sex and life stage within a species, and the proximity to coal-fired power plants. For all sites combined and species with a sample size ≥8, mean THg concentrations (μg/g dry weight) were greatest in tri-colored bats (Perimyotis subflavus; 6.04), followed by evening bats (Nycticeius humeralis; 5.89), cave myotis (Myotis velifer; 2.11), northern yellow bats (Lasiurus intermedius; 1.85), Brazilian free-tailed bats (Tadarida brasiliensis; 1.03), and red bats (Lasiurus borealis/blossevillii; 0.974), and lowest in hoary bats (Lasiurus cinereus; 0.809). Within a species, fur THg concentrations did not significantly vary between sex for the five examined species (red bat, northern yellow bat, cave myotis, evening bat, Brazilian free-tailed bat) and only between life stage in evening bats. Site variations in fur THg concentrations were observed for evening bats, tri-colored bats, and Brazilian free-tailed bats. Evening bats sampled closer to point sources of Hg pollution had greater fur THg concentrations than individuals sampled further away. Sixteen percent of evening bats and 8.7% of tri-colored bats had a fur THg concentration exceeding the 10 μg/g toxicity threshold level, suggesting that THg exposure may pose a risk to the health of bats in Texas, particularly those residing in east Texas and on the upper Gulf coast. The results of this study can be incorporated into future management and recovery plans for bats in Texas.
Collapse
Affiliation(s)
- Matthew C Parker
- Department of Biology, Texas State University, San Marcos, TX, 78666, USA.
| | - Sarah R Fritts
- Department of Biology, Texas State University, San Marcos, TX, 78666, USA.
| | | | - Melissa B Meierhofer
- Department of Rangeland, Wildlife & Fisheries Management, Texas A&M University, College Station, TX, 77843, USA; Finnish Museum of Natural History, University of Helsinki, Pohjoinen Rautatiekatu 13, 00100, Helsinki, Finland.
| | - Jessica Dutton
- Department of Biology, Texas State University, San Marcos, TX, 78666, USA.
| |
Collapse
|
2
|
Portillo A, Vega CM, Mena JL, Bonifaz E, Ascorra C, Silman MR, Fernandez LE. Mercury bioaccumulation in bats in Madre de Dios, Peru: implications for Hg bioindicators for tropical ecosystems impacted by artisanal and small-scale gold mining. ECOTOXICOLOGY (LONDON, ENGLAND) 2024; 33:457-469. [PMID: 38097853 DOI: 10.1007/s10646-023-02719-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/27/2023] [Indexed: 01/14/2024]
Abstract
Mercury (Hg) endangers human and wildlife health globally, primarily due to its release from artisanal small-scale gold mining (ASGM). During gold extraction, Hg is emitted into the environment and converted to highly toxic methylmercury by microorganisms. In Madre de Dios (MDD), Peru, ASGM dominates the economy and has transformed rainforests into expansive deforested areas punctuated by abandoned mining ponds. The aim of this study was to evaluate the use of bats as bioindicators for mercury pollution intensity in tropical terrestrial ecosystems impacted by ASGM. We collected 290 bat fur samples from three post-ASGM sites and one control site in Madre de Dios. Our results showed a wide Hg distribution in bats (0.001 to 117.71 mg/kg) strongly influenced by feeding habits. Insectivorous and piscivorous bats from ASGM sites presented elevated levels of Hg surpassing the mercury small mammal threshold for small mammals (10 mg/kg). We observed the highest reported fur mercury concentrations for insectivorous Neotropical bats reported to date (Rhynchonycteris naso, 117 mg/kg). Our findings further confirm that Hg emissions from ASGM are entering local food webs and exposing wildlife species at several trophic levels to higher levels of Hg than in areas not impacted by mining. We also found that three bat genera consistently showed increased Hg levels in ASGM sites relative to controls indicating potential usefulness as bioindicators of mercury loading in terrestrial ecosystems impacted by artisanal and small-scale gold mining.
Collapse
Affiliation(s)
- Alejandro Portillo
- Universidad Nacional de San Antonio Abad del Cusco, Museo de Historia Natural, Paraninfo Universitario (Plaza de armas s/n), Cusco, Perú.
| | - Claudia M Vega
- Centro de Innovación Científica Amazónica, Puerto Maldonado, Madre de Dios, 17000, Perú
| | - Jose Luis Mena
- Instituto de Investigaciones en Ciencias Biomédicas (INICIB), Universidad Ricardo Palma, Lima, Perú
| | - Emilio Bonifaz
- Museo de Historia Natural Vera Alleman Haeghebaert, Universidad Ricardo Palma, Lima, Peru
| | - Cesar Ascorra
- Centro de Innovación Científica Amazónica, Puerto Maldonado, Madre de Dios, 17000, Perú
| | - Miles R Silman
- Centro de Innovación Científica Amazónica, Puerto Maldonado, Madre de Dios, 17000, Perú
- Center for Energy, Environment and Sustainability, Wake Forest University, Winston-Salem, NC, 27106, USA
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27106, USA
| | - Luis E Fernandez
- Centro de Innovación Científica Amazónica, Puerto Maldonado, Madre de Dios, 17000, Perú
- Center for Energy, Environment and Sustainability, Wake Forest University, Winston-Salem, NC, 27106, USA
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27106, USA
- Department of Global Ecology, Carnegie Institute for Science, Stanford, CA, 94305, USA
| |
Collapse
|
3
|
Giunta F, Hernout BV, Langen TA, Twiss MR. A systematic review of trace elements in the tissues of bats (Chiroptera). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124349. [PMID: 38866315 DOI: 10.1016/j.envpol.2024.124349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/30/2024] [Accepted: 06/07/2024] [Indexed: 06/14/2024]
Abstract
Bats constitute about 22% of known mammal species; they have various ecological roles and provide many ecosystem services. Bats suffer from several threats caused by anthropization, including exposure to toxic metals and metalloids. We analyzed 75 papers in a systematic literature review to investigate how species, diet, and tissue type impact bioaccumulation. Most studies documented element accumulation in fur, liver, and kidney; at least 36 metals and metalloids have been measured in bat tissues, among the most studied were mercury and zinc. Comparisons with known toxicological thresholds for other mammals showed concerning values for mercury and zinc in bat hair, lead and some essential metals in liver, and iron and calcium in kidneys. Moreover, accumulation patterns in tissues differed depending on bat diet: insectivorous bats showed higher metal concentrations in fur than in liver and kidney while frugivorous species showed higher values in liver and kidney than in fur. Finally, among the bat species that have been studied in more than two papers, the big brown bat (Eptesicus fuscus) show values of mercury in hair and copper in liver that exceed the known thresholds; as does copper in the liver of the little brown bat (Myotis lucifugus). Most studies have been conducted in temperate North America and Eurasia, areas with the lowest bat species diversity; there is a paucity of data on tropical bat species. This review points out several information gaps in the understanding of metal contamination in bats, including a lack of measured toxicity thresholds specific for bat tissues. Data on trace element bioaccumulation and its associated health effects on bats is important for conservation of bat species, many of which are threatened.
Collapse
Affiliation(s)
- Flavia Giunta
- Department of Biology, Clarkson University, 8 Clarkson Avenue, 13699, otsdam, NY, USA
| | - Beatrice V Hernout
- Department of Biology, Clarkson University, 8 Clarkson Avenue, 13699, otsdam, NY, USA; Institute for a Sustainable Environment, Clarkson University, 8 Clarkson Avenue, 13699, Potsdam, NY, USA; Exponent Inc, 1075 Worcester St, Natick, MA, 01760, USA
| | - Tom A Langen
- Department of Biology, Clarkson University, 8 Clarkson Avenue, 13699, otsdam, NY, USA
| | - Michael R Twiss
- Department of Biology, Clarkson University, 8 Clarkson Avenue, 13699, otsdam, NY, USA; Faculty of Science, Algoma University, 1520 Queen Street East, Sault Ste. Marie, Ontario, P6A 2G4, Canada.
| |
Collapse
|
4
|
Simonis MC, Whitmore K, Dyer KE, Allira M, Demory B, Chumchal MM, Becker DJ. A paired analysis of mercury among non-invasive tissues to inform bat conservation monitoring. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.31.587502. [PMID: 38617222 PMCID: PMC11014497 DOI: 10.1101/2024.03.31.587502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Contaminant exposure can harm wildlife. However, measuring contaminant exposure in wildlife can be challenging due to accessibility of species and/or sampling tissue matrices needed to answer research questions regarding exposure. For example, in bats and other taxa that roost, it may be best to collect pooled feces from colonies for minimal disturbance to species of conservation concern, but fecal contaminant concentrations do not provide contaminant bioaccumulation estimates. Thus, there is a need for quantifying relationships between sample matrices for measuring contaminant exposure to answer research questions pertaining to wildlife health and addressing conservation needs. Our goal was to determine relationships between fecal and fur total mercury (THg). To do so, we collected paired feces and fur from Mexican free-tailed bats (Tadarida brasiliensis) in summer 2023 in western Oklahoma at a maternity roost with no known Hg point source. We analyzed THg in each sample matrix for each individual (n = 48). We found no relationship between individual fecal and fur THg. However, when averaged, fur THg was 6.11 times greater than fecal THg. This factor can be used as a screening-level risk assessment of under-roost feces, which could then be followed by direct assessments of fur THg concentrations and health impacts. We encourage the use of this conversion factor across other insectivorous bat species and sites for estimating initial risks of contaminant exposure with minimal disturbance to species of conservation concern, when timely research for conservation actions are needed, and when a contaminant point source is not yet known.
Collapse
Affiliation(s)
| | | | - Kristin E Dyer
- School of Biological Sciences, University of Oklahoma, USA
| | - Meagan Allira
- School of Biological Sciences, University of Oklahoma, USA
| | - Bret Demory
- School of Biological Sciences, University of Oklahoma, USA
| | | | | |
Collapse
|
5
|
Adams EM, Gulka JE, Yang Y, Burton MEH, Burns DA, Buxton V, Cleckner L, DeSorbo CR, Driscoll CT, Evers DC, Fisher N, Lane O, Mao H, Riva-Murray K, Millard G, Razavi NR, Richter W, Sauer AK, Schoch N. Distribution and trends of mercury in aquatic and terrestrial biota of New York, USA: a synthesis of 50 years of research and monitoring. ECOTOXICOLOGY (LONDON, ENGLAND) 2023; 32:959-976. [PMID: 37861861 DOI: 10.1007/s10646-023-02704-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/02/2023] [Indexed: 10/21/2023]
Abstract
Mercury (Hg) inputs have particularly impacted the northeastern United States due to its proximity to anthropogenic emissions sources and abundant habitats that efficiently convert inorganic Hg into methylmercury. Intensive research and monitoring efforts over the past 50 years in New York State, USA, have informed the assessment of the extent and impacts of Hg exposure on fishes and wildlife. By synthesizing Hg data statewide, this study quantified temporal trends of Hg exposure, spatiotemporal patterns of risk, the role that habitat and Hg deposition play in producing spatial patterns of Hg exposure in fish and other wildlife, and the effectiveness of current monitoring approaches in describing Hg trends. Most temporal trends were stable, but we found significant declines in Hg exposure over time in some long-sampled fish. The Adirondack Mountains and Long Island showed the greatest number of aquatic and terrestrial species with elevated Hg concentrations, reflecting an unequal distribution of exposure risk to fauna across the state. Persistent hotspots were detected for aquatic species in central New York and the Adirondack Mountains. Elevated Hg concentrations were associated with open water, forests, and rural, developed habitats for aquatic species, and open water and forested habitats for terrestrial species. Areas of consistently elevated Hg were found in areas driven by atmospheric and local Hg inputs, and habitat played a significant role in translating those inputs into biotic exposure. Continued long-term monitoring will be important in evaluating how these patterns continue to change in the face of changing land cover, climate, and Hg emissions.
Collapse
Affiliation(s)
- Evan M Adams
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA.
| | - Julia E Gulka
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Yang Yang
- Western Carolina University, 1 University Way, Cullowhee, NC, 28723, USA
| | - Mark E H Burton
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Douglas A Burns
- USGS New York Water Science Center, 425 Jordan Road, Troy, NY, 12180, USA
| | - Valerie Buxton
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, 2125 Derring Hall, 926 West Campus Drive, Blacksburg, VA, 24061, USA
- Adirondack Center for Loon Conservation, PO Box 195, Ray Brook, NY, 12977, USA
| | - Lisa Cleckner
- Finger Lakes Institute, 601 South Maine Street, Geneva, NY, 14456, USA
- Hobart and William Smith Colleges, 300 Pulteney St., Geneva, NY, 14456, USA
| | | | - Charles T Driscoll
- Syracuse University, Department of Civil and Environmental Engineering, 151 Link Hall, Syracuse, NY, 13244, USA
| | - David C Evers
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Nicholas Fisher
- Stony Brook University, School of Marine and Atmospheric Sciences, 100 Nicolls Road, Stony, NY, 11794, USA
| | - Oksana Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Huiting Mao
- SUNY-ESF Chemistry Department, 1 Forestry Derive, Syracuse, NY, 13210, USA
| | - Karen Riva-Murray
- USGS New York Water Science Center, 425 Jordan Road, Troy, NY, 12180, USA
| | - Geoffrey Millard
- Syracuse University, Department of Civil and Environmental Engineering, 151 Link Hall, Syracuse, NY, 13244, USA
- U.S.A. Environmental Protection Agency, Office of Research and Development, 26 W Martin Luther King Dr, Cincinnati, OH, 45220, USA
| | - N Roxanna Razavi
- SUNY-ESF Department of Environmental Biology, 1 Forestry Derive, Syracuse, NY, 13210, USA
| | - Wayne Richter
- New York State Department of Environmental Conservation, Division of Fish and Wildlife, 625 Broadway, Albany, NY, 12233-4756, USA
| | - Amy K Sauer
- Biodiversity Research Institute, 276 Canco Road, Portland, ME, 04103, USA
| | - Nina Schoch
- Adirondack Center for Loon Conservation, PO Box 195, Ray Brook, NY, 12977, USA
| |
Collapse
|
6
|
Bedard B, Hickey B, Chételat J, Mennigen JA. Variation in habitat use and its consequences for mercury exposure in two Eastern Ontario bat species, Myotis lucifugus and Eptesicus fuscus. ECOTOXICOLOGY (LONDON, ENGLAND) 2023; 32:845-857. [PMID: 37612563 DOI: 10.1007/s10646-023-02693-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/11/2023] [Indexed: 08/25/2023]
Abstract
The St. Lawrence River in Eastern Ontario, Canada, has been a designated an area of concern due to past industrial contamination of sediment in some areas and transport of mercury from tributaries. Previous research using bats as sentinel species identified elevated concentrations of total mercury (THg) in fur of local bats and species-specific variation between little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus). Here, we investigated the mercury exposure pathways for these two species by testing the hypothesis that diet variation, particularly the reliance on aquatic over terrestrial insects, is a determinant of local bat mercury concentrations. We analyzed THg concentration and stable isotope ratios of δ15N and δ13C in fur of little and big brown bats, and in aquatic and terrestrial insects. Big brown bats, especially males, accumulated significantly higher THg concentrations in their fur compared to little brown bats. However, this difference was not related to diet because big brown bats consumed terrestrial insects, which were lower in mercury than aquatic insects, the primary prey for little brown bats. We also evaluated whether fur THg concentrations translate into molecular changes in tissues linked to (methyl)mercury toxicity by quantifying tissue changes in global DNA methylation and mitochondrial DNA abundance. No significant changes in DNA molecular markers were observed in relation to fur THg concentration, suggesting mercury exposure to local bats did not impact molecular level changes at the DNA level. Higher mercury in bats was not associated with local aquatic contamination or genotoxicity in this study area.
Collapse
Affiliation(s)
- Bailey Bedard
- Department of Biology, University of Ottawa, Ottawa, ON, K1N6A5, Canada
- River Institute, Cornwall, ON, K6H4Z1, Canada
| | | | - John Chételat
- National Wildlife Research Centre, Environment and Climate Change Canada, Ottawa, ON, K1A0H3, Canada
| | - Jan A Mennigen
- Department of Biology, University of Ottawa, Ottawa, ON, K1N6A5, Canada.
| |
Collapse
|
7
|
Lazarus M, Sergiel A, Ferenčaković M, Orct T, Kapronczai L, Pađen L, Janz DM, Reljić S, Zwijacz-Kozica T, Zięba F, Selva N, Huber Đ. Stress and reproductive hormones in hair associated with contaminant metal(loid)s of European brown bear (Ursus arctos). CHEMOSPHERE 2023; 325:138354. [PMID: 36907481 DOI: 10.1016/j.chemosphere.2023.138354] [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: 12/30/2022] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Environmental contaminants like arsenic (As), cadmium (Cd), mercury (Hg) or lead (Pb) may disrupt hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes due to their endocrine toxicity potential. Resulting long-term physiological stress or adverse effects on wildlife reproduction and ontogeny may cause detrimental effects at the individual and population levels. However, data on environmental metal(loid)s' impact on reproductive and stress hormones in wildlife, especially large terrestrial carnivores, are scarce. Hair cortisol, progesterone and testosterone concentrations were quantified and modelled with hair As, Cd, total Hg, Pb, biological, environmental and sampling factors to test for potential effects in free-ranging brown bears (Ursus arctos) from Croatia (N = 46) and Poland (N = 27). Testosterone in males (N = 48) and females (N = 25) showed positive associations with Hg and an interaction between Cd and Pb, but a negative association with interaction between age and Pb. Higher testosterone was found in hair during its growth phase compared to quiescent phase. Body condition index was negatively associated with hair cortisol and positively associated with hair progesterone. Year and conditions of sampling were important for cortisol variation, while maturity stage for progesterone variation (lower concentrations in cubs and yearlings compared to subadult and adult bears). These findings suggest that environmental levels of Cd, Hg and Pb might influence the HPG axis in brown bears. Hair was shown to be a reliable non-invasive sample for investigating hormonal fluctuations in wildlife while addressing individual and sampling specificities.
Collapse
Affiliation(s)
- Maja Lazarus
- Institute for Medical Research and Occupational Health, Zagreb, Croatia.
| | - Agnieszka Sergiel
- Institute of Nature Conservation of Polish Academy of Sciences, Kraków, Poland.
| | | | - Tatjana Orct
- Institute for Medical Research and Occupational Health, Zagreb, Croatia.
| | | | - Lana Pađen
- Faculty of Veterinary Medicine, University of Zagreb, Croatia.
| | - David M Janz
- Toxicology Centre, University of Saskatchewan, Saskatoon, Canada; Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, Canada.
| | - Slaven Reljić
- Faculty of Veterinary Medicine, University of Zagreb, Croatia.
| | | | | | - Nuria Selva
- Institute of Nature Conservation of Polish Academy of Sciences, Kraków, Poland; Departamento de Ciencias Integradas, Facultad de Ciencias Experimentales, Centro de Estudios Avanzados en Física, Matemáticas y Computación, Universidad de Huelva, Huelva, Spain.
| | - Đuro Huber
- Institute of Nature Conservation of Polish Academy of Sciences, Kraków, Poland; Faculty of Veterinary Medicine, University of Zagreb, Croatia.
| |
Collapse
|
8
|
Peterson SH, Ackerman JT, Holser RR, McDonald BI, Costa DP, Crocker DE. Mercury Bioaccumulation and Cortisol Interact to Influence Endocrine and Immune Biomarkers in a Free-Ranging Marine Mammal. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5678-5692. [PMID: 36996077 DOI: 10.1021/acs.est.2c08974] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Mercury bioaccumulation from deep-ocean prey and the extreme life history strategies of adult female northern elephant seals (Mirounga angustirostris) provide a unique system to assess the interactive effects of mercury and stress on animal health by quantifying blood biomarkers in relation to mercury (skeletal muscle and blood mercury) and cortisol concentrations. The thyroid hormone thyroxine (tT4) and the antibody immunoglobulin E (IgE) were associated with mercury and cortisol concentrations interactively, where the magnitude and direction of the association of each biomarker with mercury or cortisol changed depending on the concentration of the other factor. For example, when cortisol concentrations were lowest, tT4 was positively related to muscle mercury, whereas tT4 had a negative relationship with muscle mercury in seals that had the highest cortisol concentrations. Additionally, we observed that two thyroid hormones, triiodothyronine (tT3) and reverse triiodothyronine (rT3), were negatively (tT3) and positively (rT3) associated with mercury concentrations and cortisol in an additive manner. As an example, tT3 concentrations in late breeding seals at the median cortisol concentration decreased by 14% across the range of observed muscle mercury concentrations. We also observed that immunoglobulin M (IgM), the pro-inflammatory cytokine IL-6 (IL-6), and a reproductive hormone, estradiol, were negatively related to muscle mercury concentrations but were not related to cortisol. Specifically, estradiol concentrations in late molting seals decreased by 50% across the range of muscle mercury concentrations. These results indicate important physiological effects of mercury on free-ranging apex marine predators and interactions between mercury bioaccumulation and extrinsic stressors. Deleterious effects on animals' abilities to maintain homeostasis (thyroid hormones), fight off pathogens and disease (innate and adaptive immune system), and successfully reproduce (endocrine system) can have significant individual- and population-level consequences.
Collapse
Affiliation(s)
- Sarah H Peterson
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California 95620, United States of America
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States of America
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California 95064, United States of America
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, California 95620, United States of America
| | - Rachel R Holser
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States of America
| | - Birgitte I McDonald
- Moss Landing Marine Labs, San Jose State University, Moss Landing, California 95039, United States of America
| | - Daniel P Costa
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States of America
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California 95064, United States of America
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, California 94928, United States of America
| |
Collapse
|
9
|
Rebolloso Hernández CA, Vallejo Pérez MR, Razo Soto I, Díaz-Barriga Martínez F, Yáñez LC. Mercury entomotoxicology. CHEMOSPHERE 2023; 311:136965. [PMID: 36280115 DOI: 10.1016/j.chemosphere.2022.136965] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/03/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
Mercury is an industrial pollutant of global concern. Currently entomofauna is disappearing and chemical pollution is one cause, however, it is unknown whether mercury is an additional threat. Therefore, it is necessary to know the entomotoxicology of mercury. The aim of the present work was to perform a comprehensive literature review on the entomotoxicology of mercury. The toxicokinetics and toxicity of mercury in insects, the participation of insects in the mercury cycle and the fact that this element is a threat to entomofauna are characterized. Insects can be exposed to mercury through ingestion, tracheal respiration, and gill respiration. Organic forms of mercury are better absorbed, bioaccumulated and distributed than inorganic forms. In addition, insects can biotransform mercury, for example, by methylating it. Metal elimination occurs through feces, eggs and exuvia. Toxicity molecular mechanisms include oxidative stress, enzymatic disruptions, alterations in the metabolism of neurotransmitters and proteins, genotoxicity, cell death and unbalances in the energetic state. Moreover, mercury affects lipid, germ, and gut cells, causes deformations, disturbs development, reproduction, behavior, and locomotion, besides to alters insect populations and communities. In terrestrial ecosystems, entomofauna participate in the mercury cycle by bioaccumulating mercury from soil and air, predating, being predated and decomposing organic matter. In aquatic ecosystems insects participate by accumulating mercury from water and sediment, predating, being predated and transporting it to terrestrial ecosystems when they emerge as winged adults. There are still information gaps that need to be addressed.
Collapse
Affiliation(s)
- Carlos Alberto Rebolloso Hernández
- Programa Multidisciplinario de Posgrado en Ciencias Ambientales, Universidad Autónoma de San Luis Potosí, Avenida Manuel Nava No. 201, CP 78210, Zona Universitaria, San Luis Potosí, SLP, Mexico.
| | - Moisés Roberto Vallejo Pérez
- CONACYT, Coordinación para la Innovación y Aplicación de la Ciencia y Tecnología (CIACYT), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
| | - Israel Razo Soto
- Facultad de Ingeniería, Universidad Autónoma de San Luis Potosí, Avenida Manuel Nava No. 304, CP 78210, Zona Universitaria, San Luis Potosí, SLP, Mexico
| | - Fernando Díaz-Barriga Martínez
- Facultad de Medicina-Centro de Investigación Aplicada en Ambiente y Salud (CIAAS), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
| | - Leticia Carrizales Yáñez
- Facultad de Medicina-Centro de Investigación Aplicada en Ambiente y Salud (CIAAS), Universidad Autónoma de San Luis Potosí, Avenida Sierra Leona No. 550, CP 78210, Colonia Lomas Segunda Sección, San Luis Potosí, SLP, Mexico
| |
Collapse
|
10
|
Sandoval-Herrera NI, Mastromonaco GF, Becker DJ, Simmons NB, Welch KC. Inter- and intra-specific variation in hair cortisol concentrations of Neotropical bats. CONSERVATION PHYSIOLOGY 2021; 9:coab053. [PMID: 34267922 PMCID: PMC8278960 DOI: 10.1093/conphys/coab053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 06/13/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Quantifying hair cortisol has become popular in wildlife ecology for its practical advantages for evaluating stress. Before hair cortisol levels can be reliably interpreted, however, it is key to first understand the intrinsic factors explaining intra- and inter-specific variation. Bats are an ecologically diverse group of mammals that allow studying such variation. Given that many bat species are threatened or have declining populations in parts of their range, minimally invasive tools for monitoring colony health and identifying cryptic stressors are needed to efficiently direct conservation efforts. Here we describe intra- and inter-specific sources of variation in hair cortisol levels in 18 Neotropical bat species from Belize and Mexico. We found that fecundity is an important ecological trait explaining inter-specific variation in bat hair cortisol. Other ecological variables such as colony size, roost durability and basal metabolic rate did not explain hair cortisol variation among species. At the individual level, females exhibited higher hair cortisol levels than males and the effect of body mass varied among species. Overall, our findings help validate and accurately apply hair cortisol as a monitoring tool in free-ranging bats.
Collapse
Affiliation(s)
- Natalia I Sandoval-Herrera
- Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, M5S 3B2, Canada
- Department of Biological Sciences, University of Toronto Scarborough, Ontario, M1C 1A4, Canada
| | | | - Daniel J Becker
- Department of Biology, University of Oklahoma, Norman, OK 73019, USA
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, 10024-5102, USA
| | - Kenneth C Welch
- Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, M5S 3B2, Canada
- Department of Biological Sciences, University of Toronto Scarborough, Ontario, M1C 1A4, Canada
| |
Collapse
|
11
|
Webster AM, Cleckner LB, Razavi NR. Mercury Concentrations in Big Brown Bats (Eptesicus fuscus) of the Finger Lakes Region, New York. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 81:1-14. [PMID: 33796893 DOI: 10.1007/s00244-021-00839-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
The northeastern United States receives elevated mercury (Hg) deposition from United States and global emissions, making it critical to understand the fate of Hg in watersheds with a variety of aquatic habitats and land use types, such as the Finger Lakes region of New York State. Bats are valuable and important organisms to study chronic Hg exposure, because they are at risk of sublethal effects from elevated Hg exposure. The objectives of this study were to: (1) determine total Hg (THg) and methylmercury (MeHg) concentrations in big brown bats (Eptesicus fuscus) of the Finger Lakes region; (2) assess whether morphometric, temporal, or spatial factors predict bat Hg concentrations; and (3) investigate the role of trophic position and diet represented by stable isotopes of carbon and nitrogen in explaining variations in bat Hg concentrations. We found comparable THg and MeHg concentrations to previous studies (THg range 1-45 ppm, MeHg range 0.5-38 ppm) in big brown bat fur collected throughout the Finger Lakes region. On average, MeHg made up 81% of THg in bat fur. Fifteen percent of our samples showed higher THg than a proposed toxicity threshold of 10 ppm. Together, dominant land cover and % wetland cover explained bat THg in the Finger Lakes. Trophic position (i.e., δ15N) was strongest in predicting bat THg in forests but was a weaker predictor of Hg bioaccumulation in bats from agricultural and urban areas. The range of Hg concentrations found in this study warrants further examination into the potential toxicological impacts of Hg to wildlife and the role of land use in Hg exposure to terrestrial organisms of the Finger Lakes.
Collapse
Affiliation(s)
- Abby M Webster
- Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA.
| | - Lisa B Cleckner
- Finger Lakes Institute, Hobart and William Smith Colleges, Geneva, NY, 14556, USA
| | - N Roxanna Razavi
- Department of Environmental Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA
| |
Collapse
|
12
|
Becker DJ, Speer KA, Korstian JM, Volokhov DV, Droke HF, Brown AM, Baijnauth CL, Padgett-Stewart T, Broders HG, Plowright RK, Rainwater TR, Fenton MB, Simmons NB, Chumchal MM. Disentangling interactions among mercury, immunity and infection in a Neotropical bat community. J Appl Ecol 2021; 58:879-889. [PMID: 33911313 PMCID: PMC8078557 DOI: 10.1111/1365-2664.13809] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 12/01/2020] [Indexed: 12/13/2022]
Abstract
1. Contaminants such as mercury are pervasive and can have immunosuppressive effects on wildlife. Impaired immunity could be important for forecasting pathogen spillover, as many land-use changes that generate mercury contamination also bring wildlife into close contact with humans and domestic animals. However, the interactions among contaminants, immunity and infection are difficult to study in natural systems, and empirical tests of possible directional relationships remain rare. 2. We capitalized on extreme mercury variation in a diverse bat community in Belize to test association among contaminants, immunity and infection. By comparing a previous dataset of bats sampled in 2014 with new data from 2017, representing a period of rapid agricultural land conversion, we first confirmed bat species more reliant on aquatic prey had higher fur mercury. Bats in the agricultural habitat also had higher mercury in recent years. We then tested covariation between mercury and cellular immunity and determined if such relationships mediated associations between mercury and bacterial pathogens. As bat ecology can dictate exposure to mercury and pathogens, we also assessed species-specific patterns in mercury-infection relationships. 3. Across the bat community, individuals with higher mercury had fewer neutrophils but not lymphocytes, suggesting stronger associations with innate immunity. However, the odds of infection for haemoplasmas and Bartonella spp. were generally lowest in bats with high mercury, and relationships between mercury and immunity did not mediate infection patterns. Mercury also showed species- and clade-specific relationships with infection, being associated with especially low odds for haemoplasmas in Pteronotus mesoamericanus and Dermanura phaeotis. For Bartonella spp., mercury was associated with particularly low odds of infection in the genus Pteronotus but high odds in the subfamily Stenodermatinae. 4. Synthesis and application. Lower general infection risk in bats with high mercury despite weaker innate defense suggests contaminant-driven loss of pathogen habitat (i.e. anemia) or vector mortality as possible causes. Greater attention to these potential pathways could help disentangle relationships among contaminants, immunity and infection in anthropogenic habitats and help forecast disease risks. Our results also suggest that contaminants may increase infection risk in some taxa but not others, emphasizing the importance of considering surveillance and management at different phylogenetic scales.
Collapse
Affiliation(s)
| | - Kelly A. Speer
- Richard Gilder Graduate School, American Museum of Natural History, New York, NY, USA
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
- Center for Conservation Genomics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA
| | | | - Dmitriy V. Volokhov
- Center for Biologies Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA
| | - Hannah F. Droke
- Department of Global and Planetary Health, University of South Florida, Tampa, FL, USA
| | - Alexis M. Brown
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY, USA
| | - Catherene L. Baijnauth
- Sackler Institute of Comparative Genomics, American Museum of Natural History, New York, NY, USA
| | - Ticha Padgett-Stewart
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Hugh G. Broders
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Raina K. Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Thomas R. Rainwater
- Department of Forestry and Environmental Conservation, Clemson University, Clemson, SC, USA
- Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
- Tom Yawkey Wildlife Center, Georgetown, SC, USA
| | - M. Brock Fenton
- Department of Biology, Western University, London, ON, Canada
| | - Nancy B. Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA
| | | |
Collapse
|
13
|
Eccles KM, Thomas PJ, Chan HM. Spatial patterns of the exposure-response relationship between mercury and cortisol in the fur of river otter (Lontra canadensis). CHEMOSPHERE 2021; 263:127992. [PMID: 32835981 DOI: 10.1016/j.chemosphere.2020.127992] [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] [Received: 05/14/2020] [Revised: 08/09/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
Fur has been validated as a useful biomarker medium for chemical exposures and biological responses in wildlife. Mercury (Hg) is known to act as an endocrine disruptor by altering brain neurochemistry. In this study, we investigated the spatial patterns of relationships between total Hg (THg) and cortisol in the fur of river otter (Lontra canadensis). Geotagged fur samples were obtained from a wildlife biomonitoring program (n = 72) and the North American Fur Auction (n = 37) between 2014 and 2017. Fur THg was measured using direct thermal decomposition and fur cortisol was measured using an enzyme-linked immunosorbent assay (ELISA). The average fur THg concentration was 11.50 ± 12.40 μg/g fur weight (f.w.), and the fur cortisol concentration was 5.71 ± 8.24 pg/mg. Results from the global ordinary least squares regression show no relationship between THg and fur cortisol concentrations. However, both Hg and cortisol were heterogeneously distributed across the landscape. When a localized geographically weighted regression (GWR) was used, a geographically distinct bi-phasic relationship was observed. We suggest this bi-phasic relationship is associated with a threshold THg concentration, beyond which, there was a negative association with measured fur cortisol. Results of a break-point analysis, with one break, indicate that the threshold is 16 ± 1.27 μg/g f. w of THg in fur. This research highlights the need to use appropriate spatial methods when assessing exposure-response relationships in wildlife across large geographical areas. The identified threshold can be used for regulatory purposes.
Collapse
Affiliation(s)
- Kristin M Eccles
- Department of Biology, University of Ottawa, 180, Gendron Hall, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada.
| | - Philippe J Thomas
- Department of Biology, University of Ottawa, 180, Gendron Hall, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada; Science and Technology Branch, Environment and Climate Change Canada, National Wildlife Research Center, 1125, Colonel By Drive, Raven Road, Ottawa, ON K1A 0H3, Canada.
| | - Hing Man Chan
- Department of Biology, University of Ottawa, 180, Gendron Hall, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada.
| |
Collapse
|
14
|
Naslund LC, Gerson JR, Brooks AC, Walters DM, Bernhardt ES. Contaminant Subsidies to Riparian Food Webs in Appalachian Streams Impacted by Mountaintop Removal Coal Mining. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3951-3959. [PMID: 32189492 DOI: 10.1021/acs.est.9b05907] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Selenium is highly elevated in Appalachian streams and stream organisms that receive alkaline mine drainage from mountaintop removal coal mining compared to unimpacted streams in the region. Adult aquatic insects can be important vectors of waterborne contaminants to riparian food webs, yet pathways of Se transport and exposure of riparian organisms are poorly characterized. We investigated Se concentrations in stream and riparian organisms to determine whether mining extent increased Se uptake in stream biofilms and insects and if these insects were effective Se biovectors to riparian spiders. Biofilm Se concentration increased (p = 0.006) with mining extent, reaching a maximum value of 16.5 μg/g of dw. Insect and spider Se increased with biofilm Se (p = 0.004, p = 0.003), reaching 95 and 26 μg/g of dw, respectively, in mining-impacted streams. Adult insect biomass was not related to mining extent or Se concentrations in biofilm. Even though Se concentrations in aquatic insects were significantly and positively related to mining extent, aquatic insect Se flux was not associated with mining extent because the mass of emerging insects did not change appreciably over the mining gradient. Insect and spider Se concentrations were among the highest reported in the literature, regularly exceeding the bird Se dietary risk threshold of 5 μg/g of dw. Risks of Se exposure and toxicity related to mining are thus not constrained to aquatic systems but extend to terrestrial habitats and food webs.
Collapse
Affiliation(s)
- Laura C Naslund
- Department of Biology, Duke University, Durham, North Carolina 27708, United States
| | - Jacqueline R Gerson
- Department of Biology, Duke University, Durham, North Carolina 27708, United States
| | - Alexander C Brooks
- Department of Geoscience, Colorado State University, Fort Collins, Colorado 80521, United States
| | - David M Walters
- U.S. Geological Survey, Columbia Environmental Research Center, Columbia, Missouri 65201, United States
| | - Emily S Bernhardt
- Department of Biology, Duke University, Durham, North Carolina 27708, United States
| |
Collapse
|
15
|
Durkalec M, Nawrocka A, Żmudzki J, Filipek A, Niemcewicz M, Posyniak A. Concentration of Mercury in the Livers of Small Terrestrial Rodents from Rural Areas in Poland. Molecules 2019; 24:molecules24224108. [PMID: 31739423 PMCID: PMC6891690 DOI: 10.3390/molecules24224108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/12/2019] [Accepted: 11/12/2019] [Indexed: 11/23/2022] Open
Abstract
Small terrestrial mammals could be used as accumulative biomonitors of different environmental contaminants, but the knowledge of the level of Hg in their bodies is scant. The aim of our research was to verify the factors influencing Hg bioaccumulation and to analyze the concentration of total mercury (Hg) in the livers of four species of wild terrestrial rodents from different rural areas of Poland: the yellow-necked mouse (Apodemus flavicollis), striped field mouse (Apodemus agrarius), common vole (Microtus arvalis), and bank vole (Myodes glareolus). The concentration of total Hg was analyzed in liver tissue by atomic absorption spectrometry using a direct mercury analyzer. The concentration of Hg found in the livers of rodents ranged from <1 to 36.4 µg/kg of wet weight, differed between study sites, species, and sexes, and was related to body weight. We addressed feeding habits as potential causes of differences in liver Hg concentration among species.
Collapse
Affiliation(s)
- Maciej Durkalec
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Aleja Partyzantow 57, 24-100 Puławy, Poland; (A.N.); (A.F.); (A.P.)
- Correspondence: ; Tel.: +48-81-889-3165
| | - Agnieszka Nawrocka
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Aleja Partyzantow 57, 24-100 Puławy, Poland; (A.N.); (A.F.); (A.P.)
| | - Jacek Żmudzki
- Department of Swine Diseases; National Veterinary Research Institute, Aleja Partyzantow 57, 24-100 Puławy, Poland;
| | - Aleksandra Filipek
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Aleja Partyzantow 57, 24-100 Puławy, Poland; (A.N.); (A.F.); (A.P.)
| | - Marcin Niemcewicz
- Biological Threats Identification and Countermeasure Centre, Military Institute of Hygiene and Epidemiology, Lubelska 2, 24-100 Puławy, Poland;
| | - Andrzej Posyniak
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Aleja Partyzantow 57, 24-100 Puławy, Poland; (A.N.); (A.F.); (A.P.)
| |
Collapse
|
16
|
Ruiz SR, Eeva T, Kanerva M, Blomberg A, Lilley TM. Metal and metalloid exposure and oxidative status in free-living individuals of Myotis daubentonii. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 169:93-102. [PMID: 30439584 DOI: 10.1016/j.ecoenv.2018.10.083] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 10/20/2018] [Accepted: 10/23/2018] [Indexed: 06/09/2023]
Abstract
Metal elements, ubiquitous in the environment, can cause negative effects in long-lived organisms even after low but prolonged exposure. Insectivorous bats living near metal emission sources can be vulnerable to such contaminants. Although it is known that bats can bioaccumulate metals, little information exists on the effects of metal elements on their physiological status. For example, oxidative status markers are known to vary after detoxification processes and immune reactions. Here, for two consecutive summers, we sampled individuals from a natural population of the insectivorous bat, Myotis daubentonii, inhabiting a site close to a metal emission source. We quantified metals and metalloids (As, Ca, Cd, Co, Cu, Mn, Ni, Pb, Se, Zn) from individual fecal pellets. We measured enzymatic antioxidants (GP, CAT, SOD), total glutathione (tGSH) and ratio between reduced and oxidized glutathione (GSH:GSSG) from their red blood cells together with biometrics, hematocrit and parasite prevalence. In general, metal concentrations in feces of M. daubentonii reflected the exposure to ambient contamination. This was especially evident in the higher concentrations of Cd, Co, Cu and Ni close to a smelter compared to a site with less contaminant exposure. Annual differences were also observed for most elements quantified. Sex-specific differences were observed for calcium and zinc excretion. SOD and CAT enzymatic activities were associated with metal levels (principal components of six metal elements), suggesting early signs of chronic stress in bats. The study also shows promise for the use of non-invasive sampling to assess the metal exposure on an individual basis and metal contamination in the environment.
Collapse
Affiliation(s)
- Sandra R Ruiz
- Department of Biology, University of Turku, 20014 Turku, Finland.
| | - Tapio Eeva
- Department of Biology, University of Turku, 20014 Turku, Finland
| | - Mirella Kanerva
- Center for Marine Environmental Studies, Ehime University, Japan
| | - Anna Blomberg
- Department of Biology, University of Turku, 20014 Turku, Finland
| | - Thomas M Lilley
- Finnish Museum of Natural History, University of Helsinki, Finland
| |
Collapse
|
17
|
Soto M, Lewis R, Curtis JT. Chronic exposure to inorganic mercury alters stress responses in male prairie voles (Microtus ochrogaster). Horm Behav 2019; 109:53-55. [PMID: 30769014 DOI: 10.1016/j.yhbeh.2019.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/27/2018] [Accepted: 02/10/2019] [Indexed: 11/19/2022]
Abstract
Male, but not female, prairie voles that experience chronic exposure to inorganic mercury display aberrant social behavior - avoiding unfamiliar conspecifics rather than approaching them. The mechanisms that underlie such behavioral changes are unknown, but likely involve the hypothalamus-pituitary-adrenal (HPA) axis. We tested this hypothesis by providing voles of both sexes with mercury chloride in their drinking water for ten weeks and then staging same-sex dyadic encounters after which plasma was assayed for corticosterone as an index of HPA activity. Consistent with sex-specific behavioral responses previously reported, mercury-treated males had lower plasma corticosterone after social encounters than did similarly-treated females or males that consumed normal drinking water. The results suggest that mercury-treated males may be less inclined toward social engagement with conspecifics due to reduced HPA activity.
Collapse
Affiliation(s)
- Marissa Soto
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, United States of America
| | - Robert Lewis
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, United States of America
| | - J Thomas Curtis
- Department of Pharmacology and Physiology, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, United States of America.
| |
Collapse
|
18
|
Heiker LM, Adams RA, Ramos CV. Mercury Bioaccumulation in Two Species of Insectivorous Bats from Urban China: Influence of Species, Age, and Land Use Type. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2018; 75:585-593. [PMID: 30027306 DOI: 10.1007/s00244-018-0547-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) is a widespread, toxic pollutant, and China is the world's largest emitter. We investigated Hg concentrations of fur in Japanese pipistrelles (Pipistrellus abramus) and Chinese noctules (Nyctalus plancyi) from Chengdu, Sichuan Province, in relation to degree of urbanization. Bats were mist-netted in June and July 2013, and the fur was analyzed via atomic absorption. Statistical comparisons were made between ages, species, and site types with unpaired t tests and between Hg concentration and body condition with Spearman's rank correlations. Across sites, adult pipistrelles (n = 10) had significantly greater concentrations than adult noctules (n = 16). Adult N. plancyi (n = 16) had significantly greater concentrations than juvenile N. plancyi (n = 14). Contrary to our predictions, there was no significant difference in Hg values between urban (n = 3) and peri-urban (n = 6) locations for P. abramus. While small sample sizes precluded additional comparisons, the highest value (33 mg/kg) came from an adult female P. abramus in the agricultural area. The relationship between body condition and Hg concentration was insignificant. However, most pipistrelles (7/13) and no noctules (0/31) had concentrations > 10 mg/kg, a threshold associated with disruption of homeostatic control and mobility. All bats had concentrations > 0.2 mg/kg, which is associated with compromised immunity. These are the first published records of contaminant concentrations from bats in China. For future studies, we recommend P. abramus as a regional bioindicator, longer term assessments of pre- and post-exposure effects, and simultaneous assessment of blood and fur Hg concentrations.
Collapse
Affiliation(s)
- Laura M Heiker
- University of Northern Colorado, 501 20th St., Greeley, CO, 80639, USA.
| | - Rick A Adams
- University of Northern Colorado, 501 20th St., Greeley, CO, 80639, USA
| | - Claire V Ramos
- University of Colorado, Pueblo, 2200 Bonforte Blvd., Pueblo, CO, 81001, USA
| |
Collapse
|
19
|
Wolfe JD, Lane OP, Brigham RM, Hall BD. Mercury exposure to red-winged blackbirds (Agelaius phoeniceus) and dragonfly (Odonata: Aeshnidae) nymphs in Prairie Pothole wetlands. Facets (Ott) 2018. [DOI: 10.1139/facets-2017-0086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Prairie Pothole Region (PPR) in the northern Great Plains is an area of ecological significance, serving as an important breeding site for avian wildlife. However, organisms feeding within the PPR may be at risk of mercury (Hg) exposure due to deposition of anthropogenic emissions and the high Hg methylation potential of PPR wetlands. We quantified Hg concentrations in red-winged blackbirds’ ( Agelaius phoeniceus (Linnaeus, 1766); RWBLs) blood, feathers, and eggs in the spring and summer breeding season and compared our values with those from RWBLs sampled from ecoregions across North America. Hg concentrations in whole water, aeshnid dragonfly nymphs, and RWBL tissues varied by wetland and were below those considered to elicit acute effects in wildlife, and egg total Hg (THg) concentrations were significantly related to spring whole water methylmercury concentrations. Only RWBL blood THg concentrations showed a clear increase in summer compared with spring, resulting in decoupling of summer blood and feather THg concentrations. Moreover, blood THg concentrations varied by ecoregion, with those impacted by an industrial point source exhibiting high Hg levels. Our study emphasizes that tissue renewal time as well as ecological factors such as competition and diet shifts are important considerations when using RWBLs to assess biological Hg exposure.
Collapse
Affiliation(s)
- Jared D. Wolfe
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| | - Oksana P. Lane
- Biodiversity Research Institute, 276 Canco Road, Portland, ME 04103, USA
| | - R. Mark Brigham
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| | - Britt D. Hall
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| |
Collapse
|
20
|
Chételat J, Hickey MBC, Poulain AJ, Dastoor A, Ryjkov A, McAlpine D, Vanderwolf K, Jung TS, Hale L, Cooke ELL, Hobson D, Jonasson K, Kaupas L, McCarthy S, McClelland C, Morningstar D, Norquay KJO, Novy R, Player D, Redford T, Simard A, Stamler S, Webber QMR, Yumvihoze E, Zanuttig M. Spatial variation of mercury bioaccumulation in bats of Canada linked to atmospheric mercury deposition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 626:668-677. [PMID: 29396333 DOI: 10.1016/j.scitotenv.2018.01.044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/05/2018] [Accepted: 01/06/2018] [Indexed: 06/07/2023]
Abstract
Wildlife are exposed to neurotoxic mercury at locations distant from anthropogenic emission sources because of long-range atmospheric transport of this metal. In this study, mercury bioaccumulation in insectivorous bat species (Mammalia: Chiroptera) was investigated on a broad geographic scale in Canada. Fur was analyzed (n=1178) for total mercury from 43 locations spanning 20° latitude and 77° longitude. Total mercury and methylmercury concentrations in fur were positively correlated with concentrations in internal tissues (brain, liver, kidney) for a small subset (n=21) of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus), validating the use of fur to indicate internal mercury exposure. Brain methylmercury concentrations were approximately 10% of total mercury concentrations in fur. Three bat species were mainly collected (little brown bats, big brown bats, and northern long-eared bats [M. septentrionalis]), with little brown bats having lower total mercury concentrations in their fur than the other two species at sites where both species were sampled. On average, juvenile bats had lower total mercury concentrations than adults but no differences were found between males and females of a species. Combining our dataset with previously published data for eastern Canada, median total mercury concentrations in fur of little brown bats ranged from 0.88-12.78μg/g among 11 provinces and territories. Highest concentrations were found in eastern Canada where bats are most endangered from introduced disease. Model estimates of atmospheric mercury deposition indicated that eastern Canada was exposed to greater mercury deposition than central and western sites. Further, mean total mercury concentrations in fur of adult little brown bats were positively correlated with site-specific estimates of atmospheric mercury deposition. This study provides the largest geographic coverage of mercury measurements in bats to date and indicates that atmospheric mercury deposition is important in determining spatial patterns of mercury accumulation in a mammalian species.
Collapse
Affiliation(s)
- John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario K1A 0H3, Canada.
| | | | - Alexandre J Poulain
- Biology Department, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Ashu Dastoor
- Air Quality Research Division, Environment and Climate Change Canada, Dorval, Quebec H9P 1J3, Canada
| | - Andrei Ryjkov
- Air Quality Research Division, Environment and Climate Change Canada, Dorval, Quebec H9P 1J3, Canada
| | - Donald McAlpine
- New Brunswick Museum, Saint John, New Brunswick E2K 1E5, Canada
| | - Karen Vanderwolf
- New Brunswick Museum, Saint John, New Brunswick E2K 1E5, Canada; Canadian Wildlife Federation, Kanata, Ontario K2M 2W1, Canada
| | - Thomas S Jung
- Yukon Department of Environment, Whitehorse, Yukon Territory Y1A 2C6, Canada
| | - Lesley Hale
- Ontario Ministry of Natural Resources & Forestry, Peterborough, Ontario K9J 8M5, Canada
| | - Emma L L Cooke
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario K1A 0H3, Canada
| | - Dave Hobson
- Alberta Environment and Parks, Edson, Alberta T7E 1T2, Canada
| | - Kristin Jonasson
- Department of Biology, Western University, London, Ontario N6A 5B7, Canada
| | - Laura Kaupas
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Sara McCarthy
- Wildlife Division, Fisheries and Land Resources, Goose Bay, Newfoundland and Labrador A0P 1E0, Canada
| | - Christine McClelland
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario K1A 0H3, Canada
| | | | - Kaleigh J O Norquay
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba R3B 2G3, Canada
| | - Richard Novy
- Golder Associates Ltd., Calgary, Alberta T2A 7W5, Canada
| | | | - Tony Redford
- Animal Health Centre, BC Ministry of Agriculture, Abbotsford, British Columbia V3G 2M3, Canada
| | - Anouk Simard
- Direction de l'expertise sur la faune terrestre, l'herpétofaune et l'avifaune, Ministère des Forêts, de la Faune et des Parcs, Québec, Quebec G1S 4X4, Canada
| | - Samantha Stamler
- Alberta Environment and Parks, Edmonton, Alberta T6H 4P2, Canada
| | - Quinn M R Webber
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba R3B 2G3, Canada
| | - Emmanuel Yumvihoze
- Biology Department, Faculty of Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Michelle Zanuttig
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario K1A 0H3, Canada
| |
Collapse
|
21
|
Kumar A, Divoll TJ, Ganguli PM, Trama FA, Lamborg CH. Presence of artisanal gold mining predicts mercury bioaccumulation in five genera of bats (Chiroptera). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 236:862-870. [PMID: 29475173 DOI: 10.1016/j.envpol.2018.01.109] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 01/17/2018] [Accepted: 01/31/2018] [Indexed: 06/08/2023]
Abstract
Mercury, a toxic trace metal, has been used extensively as an inexpensive and readily available method of extracting gold from fine-grained sediment. Worldwide, artisanal mining is responsible for one third of all mercury released into the environment. By testing bat hair from museum specimens and field collected samples from areas both impacted and unimpacted by artisanal gold mining in Perú, we show monomethylmercury (MMHg) has increased in the last 100 years. MMHg concentrations were also greatest in the highest bat trophic level (insectivores), and in areas experiencing extractive artisanal mining. Reproductive female bats had higher MMHg concentrations, and both juvenile and adult bats from mercury contaminated sites had more MMHg than those from uncontaminated sites. Bats have important ecological functions, providing vital ecosystem services such as pollination, seed dispersal, and insect control. Natural populations can act as environmental sentinels and offer the chance to expand our understanding of, and responses to, environmental and human health concerns.
Collapse
Affiliation(s)
- Anjali Kumar
- Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, USA.
| | - Timothy J Divoll
- Biodiversity Research Institute, 276 Canco Rd., Portland, ME, USA; Center for Bat Research, Outreach, and Conservation, Indiana State University, 600 Chestnut St., Terre Haute, IN, USA.
| | - Priya M Ganguli
- Woods Hole Oceanographic Institution, Marine Chemistry & Geochemistry, 266 Woods Hole Road, MS#51, Woods Hole, MA, USA; Department of Geological Sciences, Water Science Program, CalState University, Northridge, 18111 Nordhoff St., Northridge, CA, USA.
| | - Florencia A Trama
- Centro Neotropical de Entrenamiento en Humedales-Perú, Jr. Puerto Inca #174 Dept. 302, Urb. Los Olivos-Surco, Lima 33, Lima, Peru.
| | - Carl H Lamborg
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 266 Woods Hole Rd., Woods Hole, MA, USA; Department of Ocean Sciences, University of California, Santa Cruz, 1156 High St., Santa Cruz, CA, USA.
| |
Collapse
|
22
|
Becker DJ, Chumchal MM, Broders HG, Korstian JM, Clare EL, Rainwater TR, Platt SG, Simmons NB, Fenton MB. Mercury bioaccumulation in bats reflects dietary connectivity to aquatic food webs. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 233:1076-1085. [PMID: 29042136 DOI: 10.1016/j.envpol.2017.10.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 10/03/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
Mercury (Hg) is a persistent and widespread heavy metal with neurotoxic effects in wildlife. While bioaccumulation of Hg has historically been studied in aquatic food webs, terrestrial consumers can become contaminated with Hg when they feed on aquatic organisms (e.g., emergent aquatic insects, fish, and amphibians). However, the extent to which dietary connectivity to aquatic ecosystems can explain patterns of Hg bioaccumulation in terrestrial consumers has not been well studied. Bats (Order: Chiroptera) can serve as a model system for illuminating the trophic transfer of Hg given their high dietary diversity and foraging links to both aquatic and terrestrial food webs. Here we quantitatively characterize the dietary correlates of long-term exposure to Hg across a diverse local assemblage of bats in Belize and more globally across bat species from around the world with a comparative analysis of hair samples. Our data demonstrate considerable interspecific variation in hair total Hg concentrations in bats that span three orders of magnitude across species, ranging from 0.04 mg/kg in frugivorous bats (Artibeus spp.) to 145.27 mg/kg in the piscivorous Noctilio leporinus. Hg concentrations showed strong phylogenetic signal and were best explained by dietary connectivity of bat species to aquatic food webs. Our results highlight that phylogeny can be predictive of Hg concentrations through similarity in diet and how interspecific variation in feeding strategies influences chronic exposure to Hg and enables movement of contaminants from aquatic to terrestrial ecosystems.
Collapse
Affiliation(s)
- Daniel J Becker
- Odum School of Ecology, University of Georgia, Athens, GA, United States; Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, United States.
| | - Matthew M Chumchal
- Department of Biology, Texas Christian University, Fort Worth, TX, United States
| | - Hugh G Broders
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Jennifer M Korstian
- Department of Biology, Texas Christian University, Fort Worth, TX, United States
| | - Elizabeth L Clare
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Thomas R Rainwater
- Tom Yawkey Wildlife Center & Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, United States
| | - Steven G Platt
- Wildlife Conservation Society, Myanmar Program, Yangon, Myanmar
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, United States
| | - M Brock Fenton
- Department of Biology, Western University, London, Ontario, Canada
| |
Collapse
|
23
|
Korstian JM, Chumchal MM, Bennett VJ, Hale AM. Mercury contamination in bats from the central United States. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:160-165. [PMID: 28792083 DOI: 10.1002/etc.3940] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/04/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
Mercury (Hg) is a highly toxic metal that has detrimental effects on wildlife. We surveyed Hg concentrations in 10 species of bats collected at wind farms in the central United States and found contamination in all species. Mercury concentration in fur was highly variable both within and between species (range: 1.08-10.52 µg/g). Despite the distance between sites (up to 1200 km), only 2 of the 5 species sampled at multiple locations had fur Hg concentrations that differed between sites. Mercury concentrations observed in the present study all fell within the previously reported ranges for bats collected from the northeastern United States and Canada, although many of the bats we sampled had lower maximum Hg concentrations. Juvenile bats had lower concentrations of Hg in fur compared with adult bats, and we found no significant effect of sex on Hg concentrations in fur. For a subset of 2 species, we also measured Hg concentration in muscle tissue; concentrations were much higher in fur than in muscle, and Hg concentrations in the 2 tissue types were weakly correlated. Abundant wind farms and ongoing postconstruction fatality surveys offer an underutilized opportunity to obtain tissue samples that can be used to assess Hg contamination in bats. Environ Toxicol Chem 2018;37:160-165. © 2018 SETAC.
Collapse
Affiliation(s)
| | | | - Victoria J Bennett
- School of Geology, Energy and the Environment, Texas Christian University, Fort Worth, Texas, USA
| | - Amanda M Hale
- Biology Department, Texas Christian University, Fort Worth, Texas, USA
| |
Collapse
|
24
|
Moreno-Brush M, Portillo A, Brändel SD, Storch I, Tschapka M, Biester H. Mercury concentrations in bats (Chiroptera) from a gold mining area in the Peruvian Amazon. ECOTOXICOLOGY (LONDON, ENGLAND) 2018; 27:45-54. [PMID: 29101638 DOI: 10.1007/s10646-017-1869-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/09/2017] [Indexed: 06/07/2023]
Abstract
In the southeastern Peruvian Amazon, artisanal and small-scale gold mining (ASGM) is estimated to have released up to 300 tonnes of mercury (Hg) to the environment between 1995 and 2007 alone, and is claimed to be responsible for Hg concentrations above international thresholds for aquatic wildlife species. Here, we examined whether Hg concentrations in bat populations are potentially related to regional ASGM-Hg releases. We determined Hg concentrations in the fur of bats collected at three different distances from the major ASGM areas in Peru. Our findings from 204 individuals of 32 species indicate that Hg concentrations in bat fur mainly resulted from differences in feeding habits, because Hg concentrations were significantly higher in omnivorous bats than in frugivorous bats. At least in two species, populations living in ASGM-affected sites harbored higher Hg concentrations than did populations in unaffected sites. Because Hg concentrations reflect Hg dietary exposure, Hg emissions from amalgam roasting sites appear to deposit locally and enter the terrestrial food web. Although our study demonstrates that ASGM activities (and Hg point sources) increase Hg exposure in wildlife, the overall Hg concentrations reported here are relatively low. The measured Hg concentrations were below the toxicity threshold at which adverse neurological effects have been reported in rodents and mink (>10 µg g-1), and were in the range of Hg concentrations in the fur of bats from nonpoint source affected sites in other latitudes. This study emphasizes the importance of considering feeding habits when evaluating Hg concentrations in bats and other vertebrates.
Collapse
Affiliation(s)
- Mónica Moreno-Brush
- Chair of Wildlife Ecology and Management, University of Freiburg, Tennenbacher Str. 4, 79106, Freiburg, Germany.
- Institut für Geoökologie, Abt. Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19c, 38106, Braunschweig, Germany.
| | - Alejandro Portillo
- Museo de Historia Natural, Universidad Nacional San Antonio Abad del Cusco, Plaza de armas S/N (Paraninfo Universitario), Cusco, Peru.
| | - Stefan Dominik Brändel
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
- Smithsonian Tropical Research Institute, Luis Clement Ave., Bldg. 401 Tupper, Balboa Ancon, Panama, Panama
| | - Ilse Storch
- Chair of Wildlife Ecology and Management, University of Freiburg, Tennenbacher Str. 4, 79106, Freiburg, Germany
| | - Marco Tschapka
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
- Smithsonian Tropical Research Institute, Luis Clement Ave., Bldg. 401 Tupper, Balboa Ancon, Panama, Panama
| | - Harald Biester
- Institut für Geoökologie, Abt. Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19c, 38106, Braunschweig, Germany
| |
Collapse
|
25
|
The brains of bats foraging at wastewater treatment works accumulate arsenic, and have low non-enzymatic antioxidant capacities. Neurotoxicology 2017; 69:232-241. [PMID: 29248512 DOI: 10.1016/j.neuro.2017.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 12/04/2017] [Accepted: 12/11/2017] [Indexed: 01/19/2023]
Abstract
Increasing rates of urbanisation cause ubiquitous infrastructures that remove anthropogenic contaminants - particularly Wastewater Treatment Works (WWTWs) - to become stressed, and hence pollute surrounding water systems. Neoromicia nana bats are suitable models to study the effects of pollution in these environments because they exploit abundant pollutant-tolerant chironomid midges that breed at WWTWs, and consequently accumulate metals such as iron, copper and zinc in their livers and kidneys. If these metals persist in their circulatory systems, and cross the blood brain barrier (BBB) they can have adverse effects on critical functions such as flight and echolocation. The aim of this study was to investigate the potential neurological effects on N. nana foraging at WWTWs versus bats at reference sites in Durban, South Africa. Our objectives were to 1) compare trace metal levels in brain and hair samples (as a proxy for circulating metals) between N. nana foraging at WWTWs and reference sites to determine if excess metals pass through the BBB via the circulatory system; and 2) compare biomarkers of neuron function (acetylcholinesterase activity), protection (antioxidant capacity), DNA integrity (DNA fragmentation), lipid integrity (lipid peroxidation) and cell viability (caspase-3 activity) between N. nana foraging at WWTW and reference sites. We found a significantly higher concentration of arsenic in hair (p < 0.05) and brain tissue (p < 0.1) of WWTW bats compared to bats at reference sites. By contrast, acetylcholinesterase activity did not differ in bats among sites and there was no evidence of significant differences in lipid peroxidation, compromised DNA integrity or apoptosis in the brains between WWTW bats and reference site bats. However, total antioxidant capacity was significantly lower in brains of WWTW bats than bats at reference sites suggesting that antioxidant protection may be compromised. Long-term exposure to environmental pollutants at WWTWs may therefore affect cellular processes and protection mechanisms in brains of N. nana bats. It may also affect other mechanisms and functions in the brain such as mitochondrial efficiency and other neurotransmitters but that remains to be tested.
Collapse
|
26
|
Åkerblom S, de Jong J. Mercury in fur of Daubenton's bat (Myotis daubentonii) in Southern Sweden and Comparison to Ecotoxicological Thresholds. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2017; 99:561-566. [PMID: 29128886 PMCID: PMC5694529 DOI: 10.1007/s00128-017-2206-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 09/22/2017] [Indexed: 06/07/2023]
Abstract
To characterise mercury (Hg) exposure in Daubenton's bat (Myotis daubentonii, Kuhl 1817) in southern Sweden, 17 specimens were captured in 2013 and back fur samples were taken for analysis to determine Hg concentrations. The fur Hg levels determined [1.15 ± 0.27 (mean ± standard deviation, n = 17) µg Hg g-1 fresh weight (fw)] represent a baseline for comparison in future assessments of Hg exposure in bat populations in northern Europe. Mercury concentrations were close to those reported in fur from other bat species, but were lower than proposed toxicological thresholds in bats (> 30 µg Hg g-1 fw) and mice (5 µg Hg g-1 fw). This is the first study to examine Hg exposure in bats in Scandinavia.
Collapse
Affiliation(s)
- Staffan Åkerblom
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelms väg 9, 756 51, Uppsala, Sweden.
| | - Johnny de Jong
- Swedish Biodiversity Centre, Swedish University of Agricultural Sciences, Box 7016, 750 07, Uppsala, Sweden
| |
Collapse
|
27
|
Korine C, Pilosof S, Gross A, Morales-Malacara JB, Krasnov BR. The effect of water contamination and host-related factors on ectoparasite load in an insectivorous bat. Parasitol Res 2017; 116:2517-2526. [PMID: 28735468 DOI: 10.1007/s00436-017-5561-4] [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: 04/18/2017] [Accepted: 07/12/2017] [Indexed: 11/28/2022]
Abstract
We examined the effects of sex, age, and reproductive state of the insectivorous bat Pipistrellus kuhlii on the abundance and prevalence of arthropod ectoparasites (Macronyssidae and Cimicidae) in habitats with either sewage-polluted or natural bodies of water, in the Negev Desert, Israel. We chose water pollution as an environmental factor because of the importance of water availability in desert environments, particularly for P. kuhlii, which needs to drink on a daily basis. We predicted that parasite infestation rates would be affected by both environment and demographic cohort of the host. We found that female bats in the polluted site harbored significantly more mites than female bats in the natural site and that juveniles in the polluted site harbored significantly more cimicid individuals than juveniles in the natural site. We further found that age and sex (host-related factors) affected ectoparasite prevalence and intensity (i.e., the abundance of parasites) in the polluted site. Our results may suggest that the interaction between host-related and environment-related factors affected parasite infestations, with females and young bats being more susceptible to ectoparasites when foraging over polluted water. This effect may be particularly important for bats that must drink or forage above water for other wildlife that depend on drinking water for survival.
Collapse
Affiliation(s)
- Carmi Korine
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, 8499000, Beersheba, Israel.
| | - Shai Pilosof
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, 8499000, Beersheba, Israel
| | - Amit Gross
- Department of Environmental Hydrology and Microbiology, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, 8499000, Beersheba, Israel
| | - Juan B Morales-Malacara
- Laboratorio Espeleobiología y Acarología, Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, 76230, Querétaro, C.P., Mexico
| | - Boris R Krasnov
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, 8499000, Beersheba, Israel
| |
Collapse
|
28
|
Becker DJ, Chumchal MM, Bentz AB, Platt SG, Czirják GÁ, Rainwater TR, Altizer S, Streicker DG. Predictors and immunological correlates of sublethal mercury exposure in vampire bats. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170073. [PMID: 28484633 PMCID: PMC5414270 DOI: 10.1098/rsos.170073] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/21/2017] [Indexed: 05/21/2023]
Abstract
Mercury (Hg) is a pervasive heavy metal that often enters the environment from anthropogenic sources such as gold mining and agriculture. Chronic exposure to Hg can impair immune function, reducing the ability of animals to resist or recover from infections. How Hg influences immunity and susceptibility remains unknown for bats, which appear immunologically distinct from other mammals and are reservoir hosts of many pathogens of importance to human and animal health. We here quantify total Hg (THg) in hair collected from common vampire bats (Desmodus rotundus), which feed on blood and are the main reservoir hosts of rabies virus in Latin America. We examine how diet, sampling site and year, and bat demography influence THg and test the consequences of this variation for eight immune measures. In two populations from Belize, THg concentrations in bats were best explained by an interaction between long-term diet inferred from stable isotopes and year. Bats that foraged more consistently on domestic animals exhibited higher THg. However, relationships between diet and THg were evident only in 2015 but not in 2014, which could reflect recent environmental perturbations associated with agriculture. THg concentrations were low relative to values previously observed in other bat species but still correlated with bat immunity. Bats with higher THg had more neutrophils, weaker bacterial killing ability and impaired innate immunity. These patterns suggest that temporal variation in Hg exposure may impair bat innate immunity and increase susceptibility to pathogens such as bacteria. Unexpected associations between low-level Hg exposure and immune function underscore the need to better understand the environmental sources of Hg exposure in bats and the consequences for bat immunity and susceptibility.
Collapse
Affiliation(s)
- Daniel J. Becker
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, USA
- e-mail:
| | | | | | - Steven G. Platt
- Wildlife Conservation Society, Myanmar Program, Yangon, Myanmar
| | - Gábor Á. Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Thomas R. Rainwater
- Tom Yawkey Wildlife Center and Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, USA
| | - Daniel G. Streicker
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, UK
| |
Collapse
|
29
|
Lisón F, Espín S, Aroca B, Calvo JF, García-Fernández AJ. Assessment of mercury exposure and maternal-foetal transfer in Miniopterus schreibersii (Chiroptera: Miniopteridae) from southeastern Iberian Peninsula. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:5497-5508. [PMID: 28028704 DOI: 10.1007/s11356-016-8271-z] [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: 03/08/2016] [Accepted: 12/13/2016] [Indexed: 06/06/2023]
Abstract
Mercury (Hg) is a highly toxic and widely distributed metal that is bioaccumulated in insectivorous mammals and may cause adverse effects on the reproductive system. Bats are considered excellent Hg bioindicators due to their wide distribution, life span, trophic position, metabolic rate and food intake. However, few studies have analysed Hg residues in bats, and to the best of our knowledge, no studies have been made in the Iberian Peninsula. The main aim of this study was to undertake the first ever assessment of Hg exposure in Schreiber's bent-winged bats inhabiting a natural cave in the southeast of Spain. The findings suggest that Schreiber's bent-winged bats in the sampling area are chronically exposed to low levels of Hg. The Hg concentrations found in different tissues (fur, kidney, liver, muscle and brain) were below the threshold levels associated with toxic effects in mammals. Non-gestating females showed Hg concentrations in the brain and muscle that doubled those found in gestating females. This could be due to Hg mobilization from the mother to the foetus in gestating females, although other factors could contribute to explain this result such as variations in hunting areas and the insect-prey consumed and/or different energetic needs and average food consumption during the breeding season. Hg levels were 1.7 times higher, although not significant, in foetus' brains than in the maternal brains, and Hg concentration in foetus' brain was significantly correlated with levels in the corresponding mothers' kidney. These results suggest that there could be an active mother-to-foetus transfer of Hg in bats, which would be of special relevance in a scenario of higher Hg exposure than that found in this study. However, further research is needed to support this view due to the limited number of samples analysed. Given the scarce ecotoxicological data available for bats and their protected status, we encourage further opportunistic studies using carcasses found in the field, the validation of non-destructive samples such as fur and guano for Hg monitoring, and new modelling approaches that will increase the data needed for proper ecological risk assessment in bat populations.
Collapse
Affiliation(s)
- Fulgencio Lisón
- Department of Ecology and Hydrology, Faculty of Biology, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain
- Laboratorio de Ecología del Paisaje Forestal, Departamento de Ciencias Forestales, Universidad de La Frontera, P.O. Box-54-D, Temuco, Chile
| | - Silvia Espín
- Department of Toxicology, Faculty of Veterinary Medicine, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain.
- Section of Ecology, Department of Biology, University of Turku, 20014, Turku, Finland.
| | - Bárbara Aroca
- Department of Toxicology, Faculty of Veterinary Medicine, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain
| | - José F Calvo
- Department of Ecology and Hydrology, Faculty of Biology, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain
| | - Antonio J García-Fernández
- Department of Toxicology, Faculty of Veterinary Medicine, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain
| |
Collapse
|
30
|
Meillère A, Brischoux F, Bustamante P, Michaud B, Parenteau C, Marciau C, Angelier F. Corticosterone levels in relation to trace element contamination along an urbanization gradient in the common blackbird (Turdus merula). THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 566-567:93-101. [PMID: 27213675 DOI: 10.1016/j.scitotenv.2016.05.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/01/2016] [Accepted: 05/02/2016] [Indexed: 06/05/2023]
Abstract
In a rapidly urbanizing world, trace element pollution may represent a threat to human health and wildlife, and it is therefore crucial to assess both exposition levels and associated effects of trace element contamination on urban vertebrates. In this study, we investigated the impact of urbanization on trace element contamination and stress physiology in a wild bird species, the common blackbird (Turdus merula), along an urbanization gradient (from rural to moderately urbanized areas). Specifically, we described the contamination levels of blackbirds by 4 non-essential (Ag, Cd, Hg, Pb) and 9 essential trace elements (As, Co, Cr, Cu, Fe, Mn, Ni, Se, Zn), and explored the putative disrupting effects of the non-essential element contamination on corticosterone levels (a hormonal proxy for environmental challenges). We found that non-essential trace element burden (Cd and Pb specifically) increased with increasing urbanization, indicating a significant trace element contamination even in medium sized cities and suburban areas. Interestingly, the increased feather non-essential trace element concentrations were also associated with elevated feather corticosterone levels, suggesting that urbanization probably constrains birds and that this effect may be mediated by trace element contamination. Future experimental studies are now required to disentangle the influence of multiple urban-related constraints on corticosterone levels and to specifically test the influence of each of these trace elements on corticosterone secretion.
Collapse
Affiliation(s)
- Alizée Meillère
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France.
| | - François Brischoux
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France
| | - Paco Bustamante
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-Université de La Rochelle, F-17000 La Rochelle, France
| | - Bruno Michaud
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France
| | - Charline Parenteau
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France
| | - Coline Marciau
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France
| | - Frédéric Angelier
- Centre d'Études Biologiques de Chizé (CEBC), UMR 7372 CNRS-Université de La Rochelle, F-79360 Villiers-en-Bois, France
| |
Collapse
|
31
|
Chaves-Ulloa R, Taylor BW, Broadley HJ, Cottingham KL, Baer NA, Weathers KC, Ewing HA, Chen CY. Dissolved organic carbon modulates mercury concentrations in insect subsidies from streams to terrestrial consumers. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:1771-1784. [PMID: 27755696 PMCID: PMC5070544 DOI: 10.1890/15-0025.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 05/28/2023]
Abstract
Mercury (Hg) concentrations in aquatic environments have increased globally, exposing consumers of aquatic organisms to high Hg levels. For both aquatic and terrestrial consumers, exposure to Hg depends on their food sources as well as environmental factors influencing Hg bioavailability. The majority of the research on the transfer of methylmercury (MeHg), a toxic and bioaccumulating form of Hg, between aquatic and terrestrial food webs has focused on terrestrial piscivores. However, a gap exists in our understanding of the factors regulating MeHg bioaccumulation by non-piscivorous terrestrial predators, specifically consumers of adult aquatic insects. Because dissolved organic carbon (DOC) binds tightly to MeHg, affecting its transport and availability in aquatic food webs, we hypothesized that DOC affects MeHg transfer from stream food webs to terrestrial predators feeding on emerging adult insects. We tested this hypothesis by collecting data over 2 years from 10 low-order streams spanning a broad DOC gradient in the Lake Sunapee watershed in New Hampshire, USA. We found that streamwater MeHg concentration increased linearly with DOC concentration. However, streams with the highest DOC concentrations had emerging stream prey and spiders with lower MeHg concentrations than streams with intermediate DOC concentrations; a pattern that is similar to fish and larval aquatic insects. Furthermore, high MeHg concentrations found in spiders show that MeHg transfer in adult aquatic insects is an overlooked but potentially significant pathway of MeHg bioaccumulation in terrestrial food webs. Our results suggest that although MeHg in water increases with DOC, MeHg concentrations in stream and terrestrial consumers did not consistently increase with increases in streamwater MeHg concentrations. In fact, there was a change from a positive to a negative relationship between aqueous exposure and bioaccumulation at streamwater MeHg concentrations associated with DOC above ~5 mg/L. Thus, our study highlights the importance of stream DOC for MeHg dynamics beyond stream boundaries, and shows that factors modulating MeHg bioavailability in aquatic systems can affect the transfer of MeHg to terrestrial predators via aquatic subsidies.
Collapse
Affiliation(s)
- Ramsa Chaves-Ulloa
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA.
| | - Brad W Taylor
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
| | - Hannah J Broadley
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
- Environmental Studies Program, Bates College, 7 Andrews Road, Lewiston, Maine, 04240, USA
| | - Kathryn L Cottingham
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
| | - Nicholas A Baer
- Department of Natural Sciences, Colby-Sawyer College, 541 Main Street, New London, New Hampshire, 03257, USA
| | - Kathleen C Weathers
- Cary Institute of Ecosystem Studies, PO Box AB, Millbrook, New York, 12545, USA
| | - Holly A Ewing
- Environmental Studies Program, Bates College, 7 Andrews Road, Lewiston, Maine, 04240, USA
| | - Celia Y Chen
- Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire, 03755, USA
| |
Collapse
|
32
|
Evans RD, Grochowina NM, Basu N, O'Connor EM, Hickie BE, Rouvinen-Watt K, Evans HE, Chan HM. Uptake of selenium and mercury by captive mink: Results of a controlled feeding experiment. CHEMOSPHERE 2016; 144:1582-1588. [PMID: 26517385 DOI: 10.1016/j.chemosphere.2015.09.096] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/14/2015] [Accepted: 09/26/2015] [Indexed: 06/05/2023]
Abstract
Captive, juvenile, ranch-bred, male mink (Neovison vison) were fed diets containing various concentrations of methyl-mercury (MeHg) and selenium (Se) for a period of 13 weeks and then sacrificed to determine total Hg levels in fur, blood, brain, liver and kidneys and total Se concentrations in brain tissue. As MeHg concentrations in the diet increased, concentrations of total Hg in the tissues also increased with the highest level occurring in the fur > liver = kidney > brain > blood. Concentrations of Hg in the fur were correlated (r(2) > 0.97) with liver, kidney, blood and brain concentrations. The addition of Se to the mink diet did not appear to affect most tissue concentrations of total Hg nor did it affect the partitioning of Hg between the liver:blood, kidney:blood and brain:blood; however, partitioning of Hg between fur and blood was apparently affected.
Collapse
Affiliation(s)
- R D Evans
- Environmental and Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada; Water Quality Centre, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada.
| | - N M Grochowina
- Environmental and Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
| | - N Basu
- Faculty of Agricultural and Environmental Sciences, MacDonald Stewart Building, McGill University, 21111 Lakeshore Rd., St Anne de Bellevue, QC, H9X 3V9, Canada.
| | - E M O'Connor
- Environmental and Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada.
| | - B E Hickie
- Environmental and Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
| | - K Rouvinen-Watt
- Department of Plant and Animal Sciences, Faculty of Agriculture, Dalhousie University, PO Box 55, Truro, NS, B2N 5E3, Canada.
| | - H E Evans
- Environmental and Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada; Water Quality Centre, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
| | - H M Chan
- Community Health Program, University of Northern British Columbia, Prince George, BC, Canada.
| |
Collapse
|
33
|
Kelm DH, Popa-Lisseanu AG, Dehnhard M, Ibáñez C. Non-invasive monitoring of stress hormones in the bat Eptesicus isabellinus - Do fecal glucocorticoid metabolite concentrations correlate with survival? Gen Comp Endocrinol 2016; 226:27-35. [PMID: 26673871 DOI: 10.1016/j.ygcen.2015.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 09/29/2015] [Accepted: 12/04/2015] [Indexed: 12/27/2022]
Abstract
Chronic stress may negatively impact fitness and survival in wildlife. Stress hormone analysis from feces is a non-invasive tool for identifying stressors and deducing about individual and population level fitness. Although many bat populations are endangered, fecal stress hormone analysis has not been established in bats as a method for focusing conservation efforts. The isabelline serotine bat, Eptesicus isabellinus, is exposed to human disturbance as its roosts are mostly found in anthropogenic structures. Moreover, this bat is host to various diseases and survival rates between colonies may vary significantly. To validate the analysis of fecal glucocorticoid metabolites, we applied an adrenocorticotropic hormone (ACTH) challenge and tested four different enzyme immunoassays (EIA) for measuring glucocorticoid concentrations. Cortisol and its metabolites showed the highest increase in blood and feces after the ACTH challenge, but corticosterone and its metabolites also increased significantly. Baseline fecal cortisol metabolite (FCM) concentrations did not increase until 1.5h after the animals were captured, which is a convenient time lag for sample collection from captured animals. We furthermore compared baseline FCM concentrations between five colonies of E. isabellinus in Andalusia, Spain, and tested for their correlation with survival rates. FCM concentrations did not vary between colonies, but FCM levels increased with the animals' age. FCM analysis may prove a useful tool for identifying bat colonies that experience uncommon environmental stress. However, inter-individual variation in hormone secretion, due to factors such as age, may require additional information to properly interpret differences in hormone concentrations.
Collapse
Affiliation(s)
- Detlev H Kelm
- Estación Biológica de Doñana (CSIC), c/ Americo Vespucio s/n, 41092 Sevilla, Spain.
| | - Ana G Popa-Lisseanu
- Estación Biológica de Doñana (CSIC), c/ Americo Vespucio s/n, 41092 Sevilla, Spain
| | - Martin Dehnhard
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
| | - Carlos Ibáñez
- Estación Biológica de Doñana (CSIC), c/ Americo Vespucio s/n, 41092 Sevilla, Spain
| |
Collapse
|
34
|
Kwon SY, Blum JD, Nadelhoffer KJ, Timothy Dvonch J, Tsui MTK. Isotopic study of mercury sources and transfer between a freshwater lake and adjacent forest food web. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 532:220-9. [PMID: 26071963 DOI: 10.1016/j.scitotenv.2015.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 06/02/2015] [Accepted: 06/02/2015] [Indexed: 05/25/2023]
Abstract
Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ(202)Hg and Δ(199)Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of % MMHg versus δ(202)Hg and Δ(199)Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ(202)Hg and Δ(199)Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ(199)Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~20% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ(202)Hg and Δ(199)Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ(199)Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ(199)Hg values correspond to the % canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative importance of MMHg sources and complex Hg transfer pathways across ecosystem boundaries.
Collapse
Affiliation(s)
- Sae Yun Kwon
- Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109, United States.
| | - Joel D Blum
- Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109, United States; Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109, United States
| | - Knute J Nadelhoffer
- Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109, United States
| | - J Timothy Dvonch
- Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, United States
| | - Martin Tsz-Ki Tsui
- Department of Biology, University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC 27402, United States
| |
Collapse
|
35
|
Bechshoft T, Derocher AE, Richardson E, Mislan P, Lunn NJ, Sonne C, Dietz R, Janz DM, St Louis VL. Mercury and cortisol in Western Hudson Bay polar bear hair. ECOTOXICOLOGY (LONDON, ENGLAND) 2015; 24:1315-1321. [PMID: 26044932 DOI: 10.1007/s10646-015-1506-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/30/2015] [Indexed: 06/04/2023]
Abstract
Non-invasive methods of assessing animal health and life history are becoming increasingly popular in wildlife research; hair samples from polar bears (Ursus maritimus), are being used to study an ever broader range of anthropogenic and endocrine compounds. A number of contaminants are known to disrupt endocrine function in polar bears. However, the relationship between mercury and cortisol remains unknown, although mercury is an endocrine disruptor in other species. Here, we examine the relationship between concentrations of cortisol and total mercury (THg) analyzed in guard hair from 378 polar bears (184 females, 194 males) sampled in Western Hudson Bay, 2004-2012. The difference in mean cortisol concentration between female (0.8 ± 0.6 pg/mg) and male (0.7 ± 0.5 pg/mg) polar bears bordered on significance (p = 0.054). However, mean mercury concentration was significantly greater (p = 0.009) in females (4.7 ± 1.4 μg/g) than males (4.3 ± 1.2 μg/g). Hair cortisol in males was significantly influenced by mercury, age, and fatness, as well as interactions between mercury and year, mercury and fatness, and year and fatness (all: p < 0.03) (multiple regression analysis, whole model: r(2) = 0.14, F(7,185) = 4.43, p = 0.0001). Fatness was the only significant variable in the multiple regression analysis for females (r(2) = 0.06, F(1,182) = 13.0, p = 0.0004). In conclusion, a significant, but complex, relationship was found between mercury and cortisol concentrations in hair from male, but not female, polar bears.
Collapse
Affiliation(s)
- T Bechshoft
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada,
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Zukal J, Pikula J, Bandouchova H. Bats as bioindicators of heavy metal pollution: history and prospect. Mamm Biol 2015. [DOI: 10.1016/j.mambio.2015.01.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
37
|
Schreier HMC, Hsu HH, Amarasiriwardena C, Coull BA, Schnaas L, Téllez-Rojo MM, Tamayo y Ortiz M, Wright RJ, Wright RO. Mercury and psychosocial stress exposure interact to predict maternal diurnal cortisol during pregnancy. Environ Health 2015; 14:28. [PMID: 25889585 PMCID: PMC4377006 DOI: 10.1186/s12940-015-0016-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 03/10/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND Disrupted maternal prenatal cortisol production influences offspring development. Factors influencing the hypothalamic-pituitary-adrenal axis include social (e.g., stressful life events) and physical/chemical (e.g., toxic metals) pollutants. Mercury (Hg) is a common contaminant of fish and exposure is widespread in the US. No prior study has examined the joint associations of stress and mercury with maternal cortisol profiles in pregnancy. OBJECTIVES To investigate potential synergistic influences of prenatal stress and Hg exposures on diurnal cortisol in pregnant women. METHODS Analyses included 732 women (aged 27.4 ± 5.6 years) from a Mexico City pregnancy cohort. Participants collected saliva samples on two consecutive days (mean 19.52 ± 3.00 weeks gestation) and reported life stressors over the past 6 months. Hg was assessed in toe nail clippings collected during pregnancy. RESULTS There were no main effects of Hg or psychosocial stress exposure on diurnal cortisol (ps > .20) but strong evidence of interaction effects on cortisol slope (interaction B = .006, SE = .003, p = .034) and cortisol at times 1 and 2 (interaction B = -.071, SE = .028, p = .013; B = -.078, SE = .032, p = .014). Women above the median for Hg and psychosocial stress exposure experienced a blunted morning cortisol response compared to women exposed to higher stress but lower Hg levels. CONCLUSIONS Social and physical environmental factors interact to alter aspects of maternal diurnal cortisol during pregnancy. Research focusing solely on either domain may miss synergistic influences with potentially important consequences to the offspring.
Collapse
Affiliation(s)
- Hannah M C Schreier
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1198, New York, NY, 10029, USA.
| | - Hsiao-Hsien Hsu
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Chitra Amarasiriwardena
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Brent A Coull
- Department of Biostatistics, Harvard School of Public Health, Boston, MA, USA.
- Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA.
| | - Lourdes Schnaas
- Division of Research on Public Health, National Institute of Perinatology, Mexico City, Mexico.
| | - Martha María Téllez-Rojo
- Center for Evaluation Research and Surveys, National Institute of Public Health, Cuernavaca, Morelos, Mexico.
| | - Marcela Tamayo y Ortiz
- Center for Research in Nutrition and Health, National Institute of Public Health, Cuernavaca, Morelos, Mexico.
| | - Rosalind J Wright
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1198, New York, NY, 10029, USA.
| | - Robert O Wright
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| |
Collapse
|
38
|
Little ME, Burgess NM, Broders HG, Campbell LM. Mercury in little brown bat (Myotis lucifugus) maternity colonies and its correlation with freshwater acidity in Nova Scotia, Canada. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2059-2065. [PMID: 25591047 DOI: 10.1021/es5050375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Insectivorous little brown bats are exposed to elevated concentrations of mercury (Hg) through their preference for aquatic-based prey. Here we investigated spatial patterns of total Hg (THg) in fur from 10 little brown bat maternity colonies across Nova Scotia, and assessed relationships with the acidity of nearby lakes and rivers. Total Hg concentrations were measured in fur samples from 149 adult female little brown bats. Values showed significant variation among colonies (mean range 3.76-27.38 μg/g, dry weight), and 48% of individuals had Hg concentrations in excess of the 10 μg/g threshold associated with neurochemical changes in Chiroptera conspecifics (n = 26) from Virginia. Average surface water acidity parameters (pH and acid neutralization capacity) within an 8 km radius of each maternity roost showed strong negative associations with average colony fur THg concentrations. This suggests that freshwater acidity in foraging grounds explains much of the variation in average fur THg concentrations in little brown bat colonies. These findings highlight the significant role that water quality may have on Hg bioaccumulation within terrestrial species that feed on aquatic prey.
Collapse
Affiliation(s)
- Megan E Little
- Environmental Science and ‡Biology Departments, Saint Mary's University , 923 Robie Street, Halifax, Nova Scotia B3H 3C3, Canada
| | | | | | | |
Collapse
|
39
|
Wang W, Evans RD, Hickie BE, Rouvinen-Watt K, Evans HE. Methylmercury accumulation and elimination in mink (Neovison vison) hair and blood: results of a controlled feeding experiment using stable isotope tracers. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2014; 33:2873-2880. [PMID: 25258205 DOI: 10.1002/etc.2762] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 07/25/2014] [Accepted: 09/21/2014] [Indexed: 06/03/2023]
Abstract
Concentrations of metals in hair are used often to develop pharmacokinetic models for both animals and humans. Although data on uptake are available, elimination kinetics are less well understood; stable isotope tracers provide an excellent tool for measuring uptake and elimination kinetics. In the present study, methylmercury concentrations through time were measured in the hair and blood of mink (Neovison vison) during a controlled 60-d feeding experiment. Thirty-four mink were fed a standard fish-based diet for 14 d, at the end of which (day 0), 4 mink were sacrificed to determine baseline methylmercury (MeHg) concentrations. From day 0 to day 10, the remaining mink were fed a diet consisting of the base diet supplemented with 0.513 ± 0.013 µg Me(199) Hg/g and 0.163 ± 0.003 µg Me(201) Hg/g. From day 10 to day 60, mink were fed the base diet supplemented with 0.175 ± 0.024 µg Me(201) Hg/g. Animals were sacrificed periodically to determine accumulation of Me(201) Hg in blood and hair over the entire 60-d period and the elimination of Me(199) Hg over the last 50 d. Hair samples, collected from each mink and cut into 2.0-mm lengths, indicate that both isotopes of MeHg appeared in the hair closest to the skin at approximately day 10, with concentrations in the hair reaching steady state from day 39 onward. The elimination rate of Me(199) Hg from the blood was 0.05/d, and the ratio of MeHg in the hair to blood was 119. A large fraction of MeHg (22% to >100%) was stored in the hair, suggesting that in fur-bearing mammals the hair is a major route of elimination of MeHg from the body.
Collapse
Affiliation(s)
- Wei Wang
- Environmental & Life Sciences Graduate Programme, Trent University, Peterborough, Ontario, Canada
| | | | | | | | | |
Collapse
|
40
|
Speir SL, Chumchal MM, Drenner RW, Cocke WG, Lewis ME, Whitt HJ. Methyl mercury and stable isotopes of nitrogen reveal that a terrestrial spider has a diet of emergent aquatic insects. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2014; 33:2506-2509. [PMID: 25077687 DOI: 10.1002/etc.2700] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 07/10/2014] [Accepted: 07/28/2014] [Indexed: 06/03/2023]
Abstract
Terrestrial spiders transfer methyl mercury (MeHg) to terrestrial consumers such as birds, but how spiders become contaminated with MeHg is not well understood. In the present study, the authors used stable isotopes of nitrogen in combination with MeHg to determine the source of MeHg to terrestrial long-jawed orb weaver spiders (Tetragnatha sp). The authors collected spiders and a variety of other aquatic and terrestrial taxa from 10 shallow ponds in north Texas, USA. Based on MeHg concentrations and stable nitrogen isotope ratios, the authors identified distinct aquatic- and terrestrial-based food chains. Long-jawed orb weaver spiders belonged to the aquatic-based food chain, indicating that they are exposed to MeHg through their consumption of emergent aquatic insects. Additionally, the present study suggests that ecologists can use stable isotopes of nitrogen (δ(15) N) in conjunction with MeHg speciation analysis to distinguish between aquatic and terrestrial food chains.
Collapse
Affiliation(s)
- Shannon L Speir
- Biology Department, Texas Christian University, Fort Worth, Texas, USA
| | | | | | | | | | | |
Collapse
|
41
|
Karouna-Renier NK, White C, Perkins CR, Schmerfeld JJ, Yates D. Assessment of mitochondrial DNA damage in little brown bats (Myotis lucifugus) collected near a mercury-contaminated river. ECOTOXICOLOGY (LONDON, ENGLAND) 2014; 23:1419-1429. [PMID: 25048962 DOI: 10.1007/s10646-014-1284-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/27/2014] [Indexed: 06/03/2023]
Abstract
Historical discharges of Hg into the South River near the town of Waynesboro, VA, USA, have resulted in persistently elevated Hg concentrations in sediment, surface water, ground water, soil, and wildlife downstream of the discharge site. In the present study, we examined mercury (Hg) levels in in little brown bats (Myotis lucifugus) from this location and assessed the utility of a non-destructively collected tissue sample (wing punch) for determining mitochondrial DNA (mtDNA) damage in Hg exposed bats. Bats captured 1 and 3 km from the South River, exhibited significantly higher levels of total Hg (THg) in blood and fur than those from the reference location. We compared levels of mtDNA damage using real-time quantitative PCR (qPCR) analysis of two distinct regions of mtDNA. Genotoxicity is among the many known toxic effects of Hg, resulting from direct interactions with DNA or from oxidative damage. Because it lacks many of the protective protein structures and repair mechanisms associated with nuclear DNA, mtDNA is more sensitive to the effects of genotoxic chemicals and therefore may be a useful biomarker in chronically exposed organisms. Significantly higher levels of damage were observed in both regions of mtDNA in bats captured 3 km from the river than in controls. However, levels of mtDNA damage exhibited weak correlations with fur and blood THg levels, suggesting that other factors may play a role in the site-specific differences.
Collapse
Affiliation(s)
- Natalie K Karouna-Renier
- USGS Patuxent Wildlife Research Center, BARC East Bldg 308 10300 Baltimore Avenue, Beltsville, MD, 20705, USA,
| | | | | | | | | |
Collapse
|
42
|
Syaripuddin K, Kumar A, Sing KW, Halim MRA, Nursyereen MN, Wilson JJ. Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia. ECOTOXICOLOGY (LONDON, ENGLAND) 2014; 23:1164-1171. [PMID: 24840106 DOI: 10.1007/s10646-014-1258-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/06/2014] [Indexed: 06/03/2023]
Abstract
In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice.
Collapse
Affiliation(s)
- Khairunnisa Syaripuddin
- Museum of Zoology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | | | | | | | | | | |
Collapse
|
43
|
Brent RN, Berberich DA. Use of artificial stream mesocosms to investigate mercury uptake in the South River, Virginia, USA. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2014; 66:201-12. [PMID: 24253586 DOI: 10.1007/s00244-013-9964-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 11/01/2013] [Indexed: 05/27/2023]
Abstract
Mercury is a globally distributed pollutant that biomagnifies in aquatic food webs. In the United States, 4,769 water bodies fail to meet criteria for safe fish consumption due to mercury bioaccumulation. Although the majority of these water bodies are affected primarily by atmospheric deposition of mercury, legacy contamination from mining or industrial activities also contribute to fish consumption advisories for mercury. The largest mercury impairment in Virginia, a 130-mile stretch of the South and South Fork Shenandoah rivers, is posted with a fish-consumption advisory for mercury contamination that originated from mercuric sulfate discharges from a textile facility in Waynesboro, Virginia, between 1929 and 1950. Although discharges of mercury to the river ceased >60 years ago, mercury levels in fish remain greater than levels safe for human consumption. This is due to the continued cycling of historic mercury in the river and its eventual uptake and biomagnification through aquatic food webs. This study investigated the relative importance of waterborne versus sediment-borne mercury in controlling biological uptake of mercury into the aquatic food web. Twelve artificial stream channels were constructed along the contaminated South River in Crimora, Virginia, and the uncontaminated North River in nearby Port Republic, Virginia, to provide four experimental treatments: a control with no Hg exposure, a Hg in sediment exposure, a Hg in water exposure, and a Hg in sediment and water exposure. After 6 weeks of colonization and growth, algae in each treatment was collected and measured for mercury accumulation. Mercury accumulation in water-only exposures was four times greater than in sediment-only exposures and was equivalent to accumulation in treatments with combined water and sediment exposure. This indicates that mercury in the water column is much more important in controlling biological uptake than mercury in near-field sediments. As a result, future remediation efforts need to focus on strategies that either remove mercury from the water column or decrease flux to the water column.
Collapse
Affiliation(s)
- Robert N Brent
- Department of Integrated Science and Technology, James Madison University, Harrisonburg, VA, 22807, USA,
| | | |
Collapse
|
44
|
Yates DE, Adams EM, Angelo SE, Evers DC, Schmerfeld J, Moore MS, Kunz TH, Divoll T, Edmonds ST, Perkins C, Taylor R, O'Driscoll NJ. Mercury in bats from the northeastern United States. ECOTOXICOLOGY (LONDON, ENGLAND) 2014; 23:45-55. [PMID: 24271419 PMCID: PMC3884133 DOI: 10.1007/s10646-013-1150-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/30/2013] [Indexed: 05/04/2023]
Abstract
This study examines mercury exposure in bats across the northeast U.S. from 2005 to 2009. We collected 1,481 fur and 681 blood samples from 8 states and analyzed them for total Hg. A subset (n = 20) are also analyzed for methylmercury (MeHg). Ten species of bats from the northeast U.S. are represented in this study of which two are protected by the Endangered Species Act (ESA 1973) and two other species are pending review. There are four objectives in this paper: (1) to examine correlates to differences in fur-Hg levels among all of the sampling sites, including age, sex, species, and presence of a Hg point source; (2) define the relationship between blood and fur-Hg levels and the factors that influence that relationship including age, sex, species, reproductive status, and energetic condition; (3) determine the relationships between total Hg and MeHg in five common eastern bat species; and (4) assess the distribution of Hg across bat populations in the northeast. We found total blood and fur mercury was eight times higher in bats captured near point sources compared to nonpoint sources. Blood-Hg and fur-Hg were well correlated with females on average accumulating two times more Hg in fur than males. On average fur MeHg accounted for 86 % (range 71-95 %) of the total Hg in bat fur. Considering that females had high Hg concentrations, beyond that of established levels of concern, suggests there could be negative implications for bat populations from high Hg exposure since Hg is readily transferred to pups via breast milk. Bats provide an integral part of the ecosystem and their protection is considered to be of high priority. More research is needed to determine if Hg is a stressor that is negatively impacting bat populations.
Collapse
Affiliation(s)
- David E Yates
- BioDiversity Research Institute, 19 Flaggy Meadow Road, Gorham, ME, 04038, USA,
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
The State of Bats in Conservation Planning for the National Wildlife Refuge System, With Recommendations. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2013. [DOI: 10.3996/122012-jfwm-106] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
Bats face an unprecedented array of threats in the early 21st century, from traditional concerns such as habitat loss, to white nose syndrome and collisions with wind turbines. These growing challenges arise when the National Wildlife Refuge System, a system of public lands and waters that provides habitat for nearly every bat species in North America north of Mexico, is beginning its first revision cycle for its management plans, known as Comprehensive Conservation Plans. The U.S. Fish and Wildlife Service is thus uniquely positioned to assess its current contribution to sustaining viable populations of bats in the United States and incorporate those findings into the biological objectives that will guide Refuge management for the next 15 y. We present a review of the degree to which the first generation of Comprehensive Conservation Plans addresses bat conservation, and we provide recommendations to guide managers, planners, and partners in the development of the second generation of these Comprehensive Conservation Plans.
Collapse
|
46
|
Lilley TM, Ruokolainen L, Meierjohann A, Kanerva M, Stauffer J, Laine VN, Atosuo J, Lilius EM, Nikinmaa M. Resistance to oxidative damage but not immunosuppression by organic tin compounds in natural populations of Daubenton's bats (Myotis daubentonii). Comp Biochem Physiol C Toxicol Pharmacol 2013; 157:298-305. [PMID: 23369694 DOI: 10.1016/j.cbpc.2013.01.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 01/21/2013] [Accepted: 01/22/2013] [Indexed: 11/29/2022]
Abstract
The acute toxicity of organic tin compounds (OTCs) has been studied in detail. However, due to their complex nature, very little is known about species-specific methods of accumulation and consequences for food-webs. Chironomids, on which e.g. Daubenton's bats feed, may act as vectors for the transport of organic tin compounds from aquatic to terrestrial ecosystems. Bats are prone to environmental toxins because of their longevity and their ecological role as top predators. Organic tin compounds are associated with increased formation of reactive oxygen species and associated oxidative damage as well as suppression of immune function. The present paper investigates whether the OTC, tributyltin (TBT) and its metabolite, dibutyltin (DBT), accumulate in natural populations of Daubenton's bats and whether TBT-associated effects are seen in general body condition, redox balance, redox enzyme activities, associated oxidative damage of red blood cells and complement function. We discovered the concentration of bat fur DBT correlated with local marine sediment TBT concentrations. However, we did not find a correlation between the explanatory factors, bat fur DBT and marine sediment TBT concentrations, and several physiological and physical response variables apart from complement activity. Higher DBT concentrations resulted in weaker complement activity and thus a weaker immune response. Although the observed physiological effects in the present study were not strongly correlated to butyltin concentrations in fur or sediment, the result is unique for natural populations so far and raises interesting questions for future ecotoxicological studies.
Collapse
Affiliation(s)
- T M Lilley
- Section of Biology, University of Turku, Finland.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Tweedy BN, Drenner RW, Chumchal MM, Kennedy JH. Effects of fish on emergent insect-mediated flux of methyl mercury across a gradient of contamination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:1614-1619. [PMID: 23286272 DOI: 10.1021/es303330m] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We examined the effects of fish predation on emergent insect-mediated methyl mercury (MeHg) flux across a gradient of MeHg contamination in experimental ponds. Emergent insects were collected from ponds with (n = 5) and without fish (n = 5) over a six week period using floating emergence traps. We found that the potential for MeHg flux increased with Hg contamination levels of the ponds but that the realized MeHg flux of individual insect taxa was determined by fish presence. Fish acted as size-selective predators and reduced MeHg flux by suppressing emergence of large insect taxa (dragonflies and damselflies) but not small insect taxa (chironomids and microcaddisflies). MeHg flux by small insect taxa was correlated with concentrations of MeHg in terrestrial spiders along the shorelines of the study ponds, demonstrating for the first time the cross-system transport of MeHg by emergent insects to a terrestrial spider.
Collapse
Affiliation(s)
- Beth N Tweedy
- Department of Biology, Texas Christian University, Winton Scott Room 401, 2800 South University Drive, Fort Worth, Texas 76129, United States
| | | | | | | |
Collapse
|
48
|
Cristol DA, Savoy L, Evers DC, Perkins C, Taylor R, Varian-Ramos CW. Mercury in waterfowl from a contaminated river in Virginia. J Wildl Manage 2012. [DOI: 10.1002/jwmg.430] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
49
|
Lilley T, Ruokolainen L, Vesterinen E, Paasivirta L, Norrdahl K. Sediment organic tin contamination promotes impoverishment of non-biting midge species communities in the Archipelago Sea, S-W Finland. ECOTOXICOLOGY (LONDON, ENGLAND) 2012; 21:1333-1344. [PMID: 22481472 DOI: 10.1007/s10646-012-0887-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/08/2012] [Indexed: 05/31/2023]
Abstract
Chironomid species are a vital component in many benthic and terrestrial food webs; they have an important role in the detritus cycle, and are an important source of food for many species. We studied how tributyltin (TBT) in brackish water sediments affect the composition of chironomid species communities. Emergence traps were used at selected sites on a TBT gradient in the Archipelago Sea, S-W Finland. Increased sediment TBT concentration was associated with significant chironomid species turnover, which in turn was related to decreased species diversity (number of species and genera). However, the overall number of individuals did not decrease markedly with increasing TBT contamination. This suggests that the ecological role of chironomids in the food web may be preserved even under severe impoverishment of the chironomid community due to organic tin contamination. The increased prevalence of more TBT tolerant species can potentially lead to a transport of organic tin compounds between aquatic and terrestrial food webs. Furthermore, the reduced diversity of an ecologically influential group might lower the resistance of the entire food web to other environmental hazards and perturbations.
Collapse
Affiliation(s)
- T Lilley
- Section of Ecology, Department of Biology, University of Turku, 20014 Turku, Finland.
| | | | | | | | | |
Collapse
|
50
|
Nam DH, Yates D, Ardapple P, Evers DC, Schmerfeld J, Basu N. Elevated mercury exposure and neurochemical alterations in little brown bats (Myotis lucifugus) from a site with historical mercury contamination. ECOTOXICOLOGY (LONDON, ENGLAND) 2012; 21:1094-101. [PMID: 22331394 DOI: 10.1007/s10646-012-0864-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/31/2012] [Indexed: 05/04/2023]
Abstract
Despite evidence of persistent methylmercury (MeHg) contamination in the South River (Virginia, USA) ecosystem, there is little information concerning MeHg-associated neurological impacts in resident wildlife. Here we determined mercury (Hg) concentrations in tissues of insectivorous little brown bats (Myotis lucifugus) collected from a reference site and a MeHg-contaminated site in the South River ecosystem. We also explored whether neurochemical biomarkers (monoamine oxidase, MAO; acetylcholinesterase, ChE; muscarinic acetylcholine receptor, mAChR; N-methyl-D-aspartate receptor, NMDAR) previously shown to be altered by MeHg in other wildlife were associated with brain Hg levels in these bats. Concentrations of Hg (total and MeHg) in tissues were significantly higher (10-40 fold difference) in South River bats when compared to reference sites. Mean tissue mercury levels (71.9 ppm dw in liver, 7.14 ppm dw in brain, 132 ppm fw in fur) in the South River bats exceed (sub)-clinical thresholds in mammals. When compared to the South River bats, animals from the reference site showed a greater ability to demethylate MeHg in brain (33.1% of total Hg was MeHg vs. 65.5%) and liver (8.9% of total Hg was MeHg vs. 50.8%) thus suggesting differences in their ability to detoxify and eliminate Hg. In terms of Hg-associated neurochemical biomarker responses, interesting biphasic responses were observed with an inflection point between 1 and 5 ppm dw in the brain. In the reference bats Hg-associated decreases in MAO (r = -0.61; p < 0.05) and ChE (r = -0.79; p < 0.01) were found in a manner expected but these were not found in the bats from the contaminated site. Owing to high Hg exposures, differences in Hg metabolism, and the importance of the aforementioned neurochemicals in multiple facets of animal health, altered or perhaps even a lack of expected neurochemical responses in Hg-contaminated bats raise questions about the ecological and physiological impacts of Hg on the bat population as well as the broader ecosystem in the South River.
Collapse
Affiliation(s)
- Dong-Ha Nam
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA
| | | | | | | | | | | |
Collapse
|