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Gangoso L, Mateo R, Santamaría-Cervantes C, García-Alfonso M, Gimeno-Castellano C, Arrondo E, Serrano D, van Overveld T, de la Riva M, Cabrera MA, Donázar JA. Blood lead levels in an endangered vulture decline following changes in hunting activity. ENVIRONMENTAL RESEARCH 2024; 252:118712. [PMID: 38548255 DOI: 10.1016/j.envres.2024.118712] [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: 01/27/2024] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 04/04/2024]
Abstract
Lead ammunition stands out as one of the most pervasive pollutants affecting wildlife. Its impact on bird populations have spurred efforts for the phase-out of leaded gunshot in several countries, although with varying scopes and applications. Ongoing and future policy changes require data to assess the effectiveness of adopted measures, particularly in the current context of biodiversity loss. Here, we assessed the long-term changes in blood lead (Pb) levels of Egyptian vultures from the Canary Islands, Spain, which have been severely affected by Pb poisoning over the past two decades. During this period, the reduction in hunting pressure and changes in legislation regarding firearms usage for small game hunting likely contributed to a decrease in environmental Pb availability. As anticipated, our results show a reduction in Pb levels, especially after the ban on wild rabbit hunting with shotgun since 2010. This effect was stronger in the preadult fraction of the vulture population. However, we still observed elevated blood Pb levels above the background and clinical thresholds in 5.6% and 1.5% of individuals, respectively. Our results highlight the positive impact of reducing the availability of Pb from ammunition sources on individual health. Nonetheless, the continued use of Pb gunshot remains an important source of poisoning, even lethal, mainly affecting adult individuals. This poses a particular concern for long-lived birds, compounding by potential chronic effects associated with Pb bioaccumulation. Our findings align with recent studies indicating insufficient reductions in Pb levels among European birds of prey, attributed to limited policy changes and their uneven implementation. We anticipated further reductions in Pb levels among Egyptian vultures with expanded restrictions on hunting practices, including a blanket ban on Pb shot usage across all small game species.
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Affiliation(s)
- L Gangoso
- Department of Biodiversity, Ecology and Evolution, Faculty of Biological Sciences, Complutense University of Madrid, C/ José Antonio Novais 12, 28040, Madrid, Spain.
| | - R Mateo
- Instituto de Investigación en Recursos Cinegéticos-IREC, CSIC-UCLM-JCCM, Ronda de Toledo 12, 13005, Ciudad Real, Spain
| | - C Santamaría-Cervantes
- Instituto de Investigación en Recursos Cinegéticos-IREC, CSIC-UCLM-JCCM, Ronda de Toledo 12, 13005, Ciudad Real, Spain
| | - M García-Alfonso
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
| | - C Gimeno-Castellano
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
| | - E Arrondo
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain; Department of Zoology, University of Granada, Avenida Fuente Nueva s/n, 18071, Granada, Spain
| | - D Serrano
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
| | - T van Overveld
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
| | - M de la Riva
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
| | - M A Cabrera
- Dirección general de Espacios Naturales y Biodiversidad. Consejería de Transición Ecológica y Energía, Gobierno de Canarias, C/ Prof. Agustín Millares Carló, 18, 35071, Las Palmas de Gran Canaria, Spain
| | - J A Donázar
- Department of Conservation Biology, Estación Biológica de Doñana (CSIC), Américo Vespucio 26, 41092, Sevilla, Spain
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2
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Brown L, Fuchs B, Arnemo JM, Kindberg J, Rodushkin I, Zedrosser A, Pelletier F. Lead exposure in brown bears is linked to environmental levels and the distribution of moose kills. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 873:162099. [PMID: 36764533 DOI: 10.1016/j.scitotenv.2023.162099] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/27/2023] [Accepted: 02/04/2023] [Indexed: 06/18/2023]
Abstract
Lead (Pb) is heterogeneously distributed in the environment and multiple sources like Pb ammunition and fossil fuel combustion can increase the risk of exposure in wildlife. Brown bears (Ursus arctos) in Sweden have higher blood Pb levels compared to bears from other populations, but the sources and routes of exposure are unknown. The objective of this study was to quantify the contribution of two potential sources of Pb exposure in female brown bears (n = 34 individuals; n = 61 samples). We used multiple linear regressions to determine the contribution of both environmental Pb levels estimated from plant roots and moose (Alces alces) kills to blood Pb concentrations in female brown bears. We found positive relationships between blood Pb concentrations in bears and both the distribution of moose kills by hunters and environmental Pb levels around capture locations. Our results suggest that the consumption of slaughter remains discarded by moose hunters is a likely significant pathway of Pb exposure and this exposure is additive to environmental Pb exposure in female brown bears in Sweden. We suggest that spatially explicit models, incorporating habitat selection analyses of harvest data, may prove useful in predicting Pb exposure in scavengers.
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Affiliation(s)
- Ludovick Brown
- Département de biologie, Université de Sherbrooke, Sherbrooke, Canada.
| | - Boris Fuchs
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Koppang, Norway
| | - Jon M Arnemo
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Koppang, Norway; Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Jonas Kindberg
- Norwegian Institute for Nature Research, Trondheim, Norway; Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Ilia Rodushkin
- Division of Geosciences, Luleå University of Technology, Luleå, Sweden; ALS Scandinavia AB, Luleå, Sweden
| | - Andreas Zedrosser
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Bø, Telemark, Norway; Institute for Wildlife Biology and Game Management, University for Natural Resources and Life Sciences, Vienna, Austria
| | - Fanie Pelletier
- Département de biologie, Université de Sherbrooke, Sherbrooke, Canada
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Brown L, Rosabal M, Dussault C, Arnemo JM, Fuchs B, Zedrosser A, Pelletier F. Lead exposure in American black bears increases with age and big game harvest density. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 315:120427. [PMID: 36243189 DOI: 10.1016/j.envpol.2022.120427] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 09/19/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Hunting has multiple consequences for wildlife, and it can be an important source of environmental pollution. Most big game hunters use lead (Pb) ammunition that shed metal fragments in the tissues of harvested animals. These Pb fragments become available to scavengers when hunters discard contaminated slaughter remains in the environment. This exposure route has been extensively studied in avian scavengers, but few studies have investigated Pb exposure from ammunition in mammals. Mammalian scavengers, including American black bears (Ursus americanus), frequently use slaughter remains discarded by hunters. The objective of this study was to investigate whether big game harvest density influenced long-term Pb exposure in American black bears from Quebec, Canada. Our results showed that female black bears had higher tooth Pb concentrations in areas with higher big game harvest densities, but such relationship was not evident in males. We also showed that older bears had higher tooth Pb concentrations compared to younger ones. Overall, our study showed that Pb exposure increases with age in black bears and that some of that Pb likely comes from bullet fragments embedded in slaughter remains discarded by hunters. These results suggest that hunters may drive mammalian scavengers into an evolutionary trap, whereby the long-term benefits of consuming slaughter remains could be negated due to increased Pb exposure.
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Affiliation(s)
- Ludovick Brown
- Département de Biologie, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, QC, J1K 2R1, Canada.
| | - Maikel Rosabal
- Groupe de Recherche Interuniversitaire en Limnologie (GRIL), Département des Sciences biologiques, Université du Québec à Montréal, P.O. Box 8888, Succursale Centre-ville, Montréal, QC, H3C 3P8, Canada
| | - Christian Dussault
- Direction de l'expertise sur la Faune Terrestre, l'herpétofaune et l'avifaune, Ministère des Forêts, de la Faune et des Parcs, 880 Chemin Sainte-Foy, Québec, QC, G1S 4X4, Canada
| | - Jon M Arnemo
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2418, Elverum, Norway; Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, 901 83, Umeå, Sweden
| | - Boris Fuchs
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2418, Elverum, Norway
| | - Andreas Zedrosser
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, 3800, Bø, Telemark, Norway; Institute for Wildlife Biology and Game Management, University for Natural Resources and Life Sciences, 1180, Vienna, Austria
| | - Fanie Pelletier
- Département de Biologie, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, QC, J1K 2R1, Canada
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4
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Blood Lead Concentrations of Free-ranging North Florida Raptors: 2008-17. J Wildl Dis 2022; 58:409-414. [PMID: 35255124 DOI: 10.7589/jwd-d-21-00128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 12/20/2021] [Indexed: 11/20/2022]
Abstract
Whole blood samples for lead analysis were collected from 441 raptors admitted to the Zoological Medicine Service at the University of Florida between 1 January 2008 and 31 December 2017. The species included Bald Eagles (Haliaeetus leucocephalus), Ospreys (Pandio haliaetus), Black (Coragyps atratus) and Turkey (Cathartes aura) Vultures, Barred (Strix varia) and Great Horned (Bubo virginianus) Owls, and Red-tailed (Buteo jamaicensis) and Red-shouldered (Buteo lineatus) Hawks. Our hypothesis was that geography, seasonality, and hunting strategies of these species would all affect the blood lead concentrations. Blood lead concentrations were found to vary significantly between species, with known scavengers having higher values. Additionally, seasonal differences were seen between winter and summer, but the county in which these individuals were found did not alter the blood lead concentrations. We found lead contamination to be a common and considerable problem in Bald Eagles and vultures but not as evident in nocturnal and other diurnal raptors in North Florida. Furthermore, concentrations were highest during winter in this temperate location, suggesting a possible relationship with hunting seasons despite a lack of big game.
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Herring G, Eagles-Smith CA, Goodell J, Buck JA, Willacker JJ. Small-Mammal Shooting as a Conduit for Lead Exposure in Avian Scavengers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:12272-12280. [PMID: 34473489 DOI: 10.1021/acs.est.1c01041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Lead (Pb) exposure is a widespread wildlife conservation threat. Although commonly associated with Pb-based ammunition from big-game hunting, small mammals (e.g., ground squirrels) shot for recreational or pest-management purposes represent a potentially important Pb vector in agricultural regions. We measured the responses of avian scavengers to pest-shooting events and examined their Pb exposure through consumption of shot mammals. There were 3.4-fold more avian scavengers at shooting fields relative to those at fields with no recent shooting, and avian scavengers spent 1.8-fold more time feeding after recent shooting events. We isotopically labeled shot ground squirrels in the field with an enriched 15N isotope tracer; 6% of avian scavengers sampled within a 39 km radius reflected this tracer in their blood. However, 33% of the avian scavengers within the average foraging dispersal distance of nests (0.6-3.7 km) were labeled, demonstrating the importance of these shooting fields as a source of food for birds nesting in close proximity. Additionally, Pb concentrations in 48% of avian scavengers exceeded subclinical poisoning benchmarks for sensitive species (0.03-0.20 μg/g w/w), and those birds exhibited reduced δ-aminolevulinic acid dehydratase activity, indicating a biochemical effect of Pb. The use of shooting to manage small mammal pests is a common practice globally. Efforts that can reduce the use of Pb-based ammunition may lessen the negative physiological effects of Pb exposure on avian scavengers.
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Affiliation(s)
- Garth Herring
- Forest and Rangeland Ecosystem Science Center, U.S. Geological Survey, Corvallis, Oregon 97331, United States
| | - Collin A Eagles-Smith
- Forest and Rangeland Ecosystem Science Center, U.S. Geological Survey, Corvallis, Oregon 97331, United States
| | - John Goodell
- High Desert Museum, Bend, Oregon 97331, United States
| | - Jeremy A Buck
- United States Fish and Wildlife Service, 2600 SE 98th Avenue Suite 100, Portland, Oregon 97702, United States
| | - James J Willacker
- Forest and Rangeland Ecosystem Science Center, U.S. Geological Survey, Corvallis, Oregon 97331, United States
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6
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Lead Contamination Differences in the Muscle of Wild Turkeys Harvested with Lead and Copper-Plated Lead Shot. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2021. [DOI: 10.3996/jfwm-20-084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
Despite the known deleterious effects lead exposure can have on humans, lead remains the most common type of ammunition used to harvest big game and upland game birds. We sampled wild turkey Meleagris gallopavo breast muscle shot with standard lead and copper-plated lead pellets to quantify lead residue concentrations within the wound channel, and we sampled multiple adjacent locations to measure the extent lead contamination spreads through tissue of harvested turkeys. We found that samples taken from the wound channel contained more lead (mean = 3.76 μg/g dry weight) than both samples taken adjacent to the wound channel (mean = 0.20 μg/g dry weight) and samples taken from >5 cm away (mean = 0.15 μg/g dry weight). Additionally, we found that birds harvested with standard lead ammunition did not differ in lead concentrations from those shot with copper-plated lead, suggesting that copper plating does not aid in reducing lead exposure. Our findings suggest that wild turkeys harvested with either lead or copper-plated lead shot have the potential to expose consumers, especially children due to their lower tolerance, to low levels of lead that could exceed daily consumption limits set by the Food and Drug Administration and Centers for Disease Control. However, elevated lead levels were confined to the wound channel, and thus proper preparation of game to remove tissue surrounding wound channels may eliminate or substantially reduce lead exposure from harvested game birds.
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Pay JM, Katzner TE, Hawkins CE, Koch AJ, Wiersma JM, Brown WE, Mooney NJ, Cameron EZ. High Frequency of Lead Exposure in the Population of an Endangered Australian Top Predator, the Tasmanian Wedge-Tailed Eagle (Aquila audax fleayi). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2021; 40:219-230. [PMID: 33090553 PMCID: PMC7839751 DOI: 10.1002/etc.4914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/13/2020] [Accepted: 10/17/2020] [Indexed: 06/11/2023]
Abstract
Lead poisoning, mainly through incidental ingestion of lead ammunition in carcasses, is a threat to scavenging and predatory bird species worldwide. In Australia, shooting for animal control is widespread, and a range of native scavenging species are susceptible to lead exposure. However, the prevalence of lead exposure in Australia's scavenging and predatory birds is largely unknown. We evaluated the degree to which the Tasmanian wedge-tailed eagle (Aquila audax fleayi), an endangered Australian raptor and facultative scavenger, showed evidence of lead exposure. We detected lead in 100% of femur and liver tissues of 109 eagle carcasses opportunistically collected throughout Tasmania between 1996 and 2018. Concentrations were elevated in 10% of 106 liver (>6 mg/kg dry wt) and 4% of 108 femur (>10 mg/kg dry wt) samples. We also detected lead in 96% of blood samples taken from 24 live nestlings, with 8% at elevated concentrations (>10 μg/dL). Of the liver samples with elevated lead, 73% had lead207/206 isotope ratios within the published range of lead-based bullets available in Tasmania. These first comprehensive data on lead exposure of an Australian raptor are comparable to those for raptor studies elsewhere that identify lead-based ammunition exposure as a conservation threat. Our findings highlight the importance of further research and efforts to address lead contamination throughout the Tasmanian ecosystem and in other Australian regions. Environ Toxicol Chem 2021;40:219-230. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.
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Affiliation(s)
- James M. Pay
- School of Natural SciencesUniversity of TasmaniaHobartTasmaniaAustralia
| | - Todd E. Katzner
- Forest and Rangeland Ecosystem Science Center, US Geological SurveyBoiseIdahoUSA
| | - Clare E. Hawkins
- School of Natural SciencesUniversity of TasmaniaHobartTasmaniaAustralia
| | - Amelia J. Koch
- School of Natural SciencesUniversity of TasmaniaHobartTasmaniaAustralia
- Forest Practices AuthorityHobartTasmaniaAustralia
| | | | - William E. Brown
- Department of Primary Industries, Parks, Water and EnvironmentHobartTasmaniaAustralia
| | - Nick J. Mooney
- Birdlife Australia Raptor Group, Birdlife AustraliaCarltonVictoriaAustralia
| | - Elissa Z. Cameron
- School of Natural SciencesUniversity of TasmaniaHobartTasmaniaAustralia
- School of Biological SciencesUniversity of CanterburyChristchurchCanterburyNew Zealand
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Broadway MS, McCallen EB, Caudell J, Stewart CM. Ammunition Type and Shot Placement Determine Lead Fragmentation in Deer. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21917] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Matthew S. Broadway
- Indiana Division of Fish and WildlifeWildlife Science 5596 E. State Road 46 Bloomington IN 47401 USA
| | - Emily B. McCallen
- Indiana Division of Fish and WildlifeWildlife Science 5596 E. State Road 46 Bloomington IN 47401 USA
| | - Joe Caudell
- Indiana Division of Fish and WildlifeWildlife Science 5596 E. State Road 46 Bloomington IN 47401 USA
| | - Chad M. Stewart
- Michigan Department of Natural Resources 4166 Legacy Parkway Lansing MI 48911 USA
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Kotwa JD, Pearl DL, Isaksson M, Jardine CM, Berke O, Mercer NJ, Osterman-Lind E, Peregrine AS. Factors associated with Echinococcus multilocularis infection in coyotes in southern Ontario. Zoonoses Public Health 2020; 67:546-553. [PMID: 32369261 DOI: 10.1111/zph.12718] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/16/2020] [Accepted: 04/14/2020] [Indexed: 11/26/2022]
Abstract
Echinococcus multilocularis was recently reported in wild canids across southern Ontario, a newly recognized endemic area in Canada. In such areas, a comprehensive understanding of factors associated with infection in definitive hosts (wild canids) is critical for mitigating risk of transmission to humans. However, little is known about the transmission dynamics of the parasite in definitive hosts for this region. A study was therefore carried out to investigate the association of host-level (sex, body condition), environmental (southern Ontario region, land cover), temporal (season, hunting season, calendar year) and extraneous factors (submitter type) with E. multilocularis infection in coyotes in southern Ontario. Between November 2015 and March 2017, 416 coyotes were collected from across the region as part of a study that investigated the prevalence and distribution of the parasite in wild canids; approximately 24% of coyotes were positive for E. multilocularis. Associations between infection and factors of interest were assessed via a mixed-effects logistic regression model with a random intercept for submitter to account for clustering. Coyotes with poor body condition were at greater odds of E. multilocularis infection than those in good condition (odds ratio [OR] 2.14; 95% CI: 1.08-4.26; p = .030). A negative association was observed between infection in coyotes and the proportion of natural land in a coyote's estimated home range (OR: 0.67; 95% CI: 0.52-0.85; p = .001). Coyotes from the western region of southern Ontario had lower odds of infection compared to coyotes from the central region (OR: 0.26; 95% CI: 0.12-0.55; p < .001). These results can be used to help guide future public health prevention strategies for human alveolar echinococcosis.
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Affiliation(s)
- Jonathon D Kotwa
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - David L Pearl
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | | | - Claire M Jardine
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.,Canadian Wildlife Health Cooperative, Guelph, ON, Canada
| | - Olaf Berke
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Nicola J Mercer
- Wellington-Dufferin-Guelph Public Health, Guelph, ON, Canada
| | | | - Andrew S Peregrine
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
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10
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Plaza PI, Lambertucci SA. What do we know about lead contamination in wild vultures and condors? A review of decades of research. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 654:409-417. [PMID: 30447579 DOI: 10.1016/j.scitotenv.2018.11.099] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/03/2018] [Accepted: 11/07/2018] [Indexed: 06/09/2023]
Abstract
Vultures and condors (hereafter vultures) make up one the most threatened avian guilds in the world due to a variety of human-mediated impacts and disturbances. In fact, 70% of vulture species are currently suffering impacted by significant conservation threats, with lead contamination being particularly important. Unfortunately, lead contamination in vulture species remains poorly studied in many regions of the world. We reviewed the existing scientific knowledge about this threat to vultures. We found 62 scientific articles studying lead contamination in vultures. Seventy-two percent of these articles were from North America and Europe, with the rest corresponding to Asia (13%), South America (8%), and Africa (7%). Most (92%) were published recently (2001-2018). Published articles included information on 13 vulture species out of a total of 23 from both the Old (9) and New World (4). Eighty-eight percent of the articles showed individuals with lead concentrations above threshold levels in some tissues sampled, with New World (Cathartidae) vultures more affected than Old World vultures (Accipitridae). The most suspected but rarely probed source of lead was lead ammunition, but other sources such as pollution or industry were also reported. It is concerning that lead contamination is considered a major threat for just 8% (2/23) of the vulture species categorized by the IUCN Red list. Our review shows that lead contamination is an important threat for several vulture species worldwide, but remains undiagnosed and not well-recognized in some species and geographical areas. The effect of this contaminant on vulture demography is not well known but merits particular attention since it may be leading to population declines in several species.
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Affiliation(s)
- Pablo I Plaza
- Grupo de investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue - CONICET), Quintral 1250 (R8400FRF), San Carlos de Bariloche, Argentina.
| | - Sergio A Lambertucci
- Grupo de investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue - CONICET), Quintral 1250 (R8400FRF), San Carlos de Bariloche, Argentina.
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11
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Schulz JH, Wilhelm Stanis SA, Webb EB, Li CJ, Hall DM. Communication strategies for reducing lead poisoning in wildlife and human health risks. WILDLIFE SOC B 2019. [DOI: 10.1002/wsb.955] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- John H. Schulz
- School of Natural ResourcesUniversity of Missouri105 Anheuser‐Busch Natural Resources BuildingColumbiaMO65211USA
| | - Sonja A. Wilhelm Stanis
- School of Natural ResourcesUniversity of Missouri105 Anheuser‐Busch Natural Resources BuildingColumbiaMO65211USA
| | - Elisabeth B. Webb
- U.S. Geological SurveyMissouri Cooperative Fish and Wildlife Research Unit302 Anheuser‐Busch Natural Resources BuildingColumbiaMO65211USA
| | - Christine Jie Li
- School of Natural ResourcesUniversity of Missouri105 Anheuser‐Busch Natural Resources BuildingColumbiaMO65211USA
| | - Damon M. Hall
- School of Natural Resources & Department of BioengineeringUniversity of Missouri105 Anheuser‐Busch Natural Resources BuildingColumbiaMO65211USA
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12
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Janiga M, Haas M. Alpine accentors as monitors of atmospheric long-range lead and mercury pollution in alpine environments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:2445-2454. [PMID: 30471058 DOI: 10.1007/s11356-018-3742-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Mercury and lead are deposited in the West Carpathians as long-range transported air pollution. The Alpine accentor (Prunella collaris) was recognized as a cost-effective biomonitor, and used to investigate the bioavailability of contaminants in large alpine areas. The outer tail feathers and blood of the alpine accentors were used for assessment of atmospheric mercury and lead contamination, respectively. Mean mercury levels in feathers of accentors averaged at 1.15 μg/g (SE = 0.105, n = 40). There were no temporal variations in mercury concentrations. Mean blood lead levels were at 5.2 μg/dL (SE = 0.5, n = 27), showing a slight decreasing trend from July to October. Juveniles were not more susceptible to lead accumulation than adults. Bone lead concentrations that increase with age reflect a bioaccumulation effect. A statistically significant negative correlation was found between the length of erythrocytes and the concentration of lead, which may show the first symptoms of microcytosis. In comparison to aquatic ecosystems, the biogeochemical factors that influence methylmercury availability in alpine habitats are not yet completely known and require further investigation. Our findings show that birds in alpine terrestrial ecosystems may contain surprisingly high levels of methylmercury. The mercury levels in the feathers of accentors probably indicate that alpine autotrophs make sufficient amounts of mercury available to the terrestrial food web. The blood lead levels of accentors likely approach the threshold level for further hematological effects. We found a clear tendency in erythrocytes to change their shape from ellipsoid to smaller and rounder with increasing amounts of lead in their blood. The shape of bird erythrocytes appears to be a very sensitive indicator of critical levels of lead in the alpine environment.
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Affiliation(s)
- Marián Janiga
- Institute of High Mountain Biology, Žilina University, Tatranská Javorina, 7, SK-059 56, Slovak Republic
| | - Martina Haas
- Institute of High Mountain Biology, Žilina University, Tatranská Javorina, 7, SK-059 56, Slovak Republic.
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13
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Herring G, Eagles-Smith CA, Varland DE. Mercury and lead exposure in avian scavengers from the Pacific Northwest suggest risks to California condors: Implications for reintroduction and recovery. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 243:610-619. [PMID: 30218871 DOI: 10.1016/j.envpol.2018.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 09/01/2018] [Accepted: 09/02/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) and lead (Pb) are widespread contaminants that pose risks to avian scavengers. In fact, Pb exposure is the primary factor limiting population recovery in the endangered California condor (Gymnogyps californianus) and Hg can impair avian reproduction at environmentally relevant exposures. The Pacific Northwest region of the US was historically part of the condor's native range, and efforts are underway to expand recovery into this area. To identify potential threats to reintroduced condors we assessed foraging habitats, Hg and Pb exposure, and physiological responses in two surrogate avian scavenger species (common ravens [Corvus corax] and turkey vultures [Cathartes aura] across the region between 2012 and 2016. Mercury exposure near the Pacific coast was 17-27-fold higher than in inland areas, and stable carbon and sulfur isotopes ratios indicated that coastal scavengers were highly reliant on marine prey. In contrast, Pb concentrations were uniformly elevated across the region, with 18% of the birds exposed to subclinical poisoning levels. Elevated Pb concentrations were associated with lower delta-aminolevulinic acid dehydratase (δ-ALAD) activity, and in ravens there was an interactive effect between Hg and Pb on fecal corticosterone concentrations. This interaction indicated that the effects of Hg and Pb exposure on the stress axis are bidirectional, and depend on the magnitude of simultaneous exposure to the other contaminant. Our results suggest that condors released to the Pacific Northwest may be exposed to both elevated Hg and Pb, posing challenges to management of future condor populations in the Pacific Northwest. Developing a robust monitoring program for reintroduced condors and surrogate scavengers will help both better understand the drivers of exposure and predict the likelihood of impaired health. These findings provide a strong foundation for such an effort, providing resource managers with valuable information to help mitigate potential risks.
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Affiliation(s)
- Garth Herring
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR, 97331, USA
| | - Collin A Eagles-Smith
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR, 97331, USA.
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Plaza PI, Uhart M, Caselli A, Wiemeyer G, Lambertucci SA. A review of lead contamination in South American birds: The need for more research and policy changes. Perspect Ecol Conserv 2018. [DOI: 10.1016/j.pecon.2018.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Garbett R, Maude G, Hancock P, Kenny D, Reading R, Amar A. Association between hunting and elevated blood lead levels in the critically endangered African white-backed vulture Gyps africanus. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 630:1654-1665. [PMID: 29550066 DOI: 10.1016/j.scitotenv.2018.02.220] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 02/14/2018] [Accepted: 02/18/2018] [Indexed: 06/08/2023]
Abstract
Lead (Pb) toxicity caused by the ingestion of Pb ammunition fragments in carcasses and offal is a threat to scavenging birds across the globe. African vultures are in critical decline, but research on whether Pb exposure is contributing to declines is lacking. In Africa, recreational hunting represents an important economic activity; however, Pb in leftover hunted carcasses and gut piles represents a dangerous food source for vultures. It is therefore important to establish whether recreational hunting is associated with Pb exposure in African vultures. We explored this issue for the critically endangered white-backed vulture (Gyps africanus) in Botswana by examining their blood Pb levels inside and outside of the hunting season, and inside and outside of private hunting areas. From 566 birds captured and tested, 30.2% birds showed elevated Pb levels (10 to <45 μg/dl) and 2.3% showed subclinical exposure (≥45 μg/dl). Higher blood Pb levels were associated with samples taken inside of the hunting season and from within hunting areas. Additionally, there was a significant interaction between hunting season and areas, with Pb levels declining more steeply between hunting and non-hunting seasons within hunting areas than outside them. Thus, all our results were consistent with the suggestion that elevated Pb levels in this critically endangered African vulture are associated with recreational hunting. Pb is known to be highly toxic to scavenging birds and we recommend that Pb ammunition in Botswana is phased out as soon as possible to help protect this rapidly declining group of birds.
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Affiliation(s)
- Rebecca Garbett
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa; Raptors Botswana, Box Ha 33 Hak, Maun, Botswana.
| | - Glyn Maude
- Raptors Botswana, Box Ha 33 Hak, Maun, Botswana; Denver Zoological Foundation, E. 2300 Steele St, Denver, CO 80205, USA
| | | | - David Kenny
- Raptors Botswana, Box Ha 33 Hak, Maun, Botswana
| | | | - Arjun Amar
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
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Hampton JO, Laidlaw M, Buenz E, Arnemo JM. Heads in the sand: public health and ecological risks of lead-based bullets for wildlife shooting in Australia. WILDLIFE RESEARCH 2018. [DOI: 10.1071/wr17180] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Lead (Pb) is a toxic element banned from fuel, paint and many other products in most developed countries. Nonetheless, it is still widely used in ammunition, including rifle bullets, and Pb-based bullets are almost universally used in Australia. For decades, poisoning from Pb shot (shotguns) has been recognised as a cause of disease in waterfowl and Pb shot has been subsequently banned for waterfowl hunting in many jurisdictions. However, the risks posed by Pb-based bullets (rifles) have not been similarly recognised in Australia. Pb-based rifle bullets frequently fragment, contaminating the tissue of shot animals. Consuming this Pb-contaminated tissue risks harmful Pb exposure and, thus, the health of wildlife scavengers (carrion eaters) and humans and their companion animals who consume harvested meat (game eaters). In Europe, North America and elsewhere, the environmental and human health risks of Pb-based bullets are widely recognised, and non-toxic alternatives (e.g. copper-based bullets) are increasingly being used. However, Australia has no comparable research despite widespread use of shooting, common scavenging by potentially susceptible wildlife species, and people regularly consuming shot meat. We conclude that Australia has its collective ‘head in the sand’ on this pressing worldwide One Health issue. We present the need for urgent research into this field in Australia.
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Behmke S, Mazik P, Katzner T. Assessing multi-tissue lead burdens in free-flying obligate scavengers in eastern North America. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:139. [PMID: 28251454 DOI: 10.1007/s10661-017-5855-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 02/15/2017] [Indexed: 06/06/2023]
Abstract
Avian scavengers are regularly exposed to anthropogenic lead. Although many studies evaluate lead concentrations of either blood or tissues of lead-poisoned birds, there is comparatively less research on lead burdens of free-flying, apparently healthy individuals and populations. Here, we address this lack of information by assessing lead levels of multiple tissues (femur, liver, kidney, breast muscle, thigh muscle) in free-flying black vultures (n = 98) and turkey vultures (n = 10) collected outside the hunting season. We found only one individual had a soft tissue lead concentration indicative of acute exposure (6.17 mg/kg wet weight in the liver), while the other 107 vultures showed consistent low-level lead exposure throughout the soft tissues. All vultures, however, had femur lead concentrations indicative of chronic lead exposure (black vultures [Formula: see text]31.80 ± 20.42 mg/kg (±SD); turkey vultures 23.21 ± 18.77 mg/kg). Lead levels were similar in all tissues in both vulture species (in each case, p > 0.05) and were generally highest in the femur, intermediate in the kidney and liver, and lowest in the breast and thigh muscle. Despite the consistency of these patterns, there were few strong correlations between lead levels in different tissues within each species, and those correlations that did exist were not consistent between species. Because these vultures were free flying and apparently healthy, the organism-wide lead distributions and between-species trends we report here provide important insight into the sublethal lead burdens that black vultures and turkey vultures commonly carry. Furthermore, these data offer a framework to better interpret and contextualize lead exposure data collected from these and other species.
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Affiliation(s)
- Shannon Behmke
- School of Natural Resources, West Virginia University, PO Box 6125, Morgantown, WV, 26506, USA.
| | - Patricia Mazik
- U.S. Geological Survey, WV Cooperative Fish and Wildlife Research Unit, West Virginia University, Morgantown, WV, 26506, USA
| | - Todd Katzner
- School of Natural Resources, West Virginia University, PO Box 6125, Morgantown, WV, 26506, USA
- USDA Forest Service, Northern Research Station, Morgantown, WV, 26287, USA
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 970 Lusk St, Boise, ID, 83706, USA
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Wiemeyer GM, Pérez MA, Torres Bianchini L, Sampietro L, Bravo GF, Jácome NL, Astore V, Lambertucci SA. Repeated conservation threats across the Americas: High levels of blood and bone lead in the Andean Condor widen the problem to a continental scale. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 220:672-679. [PMID: 27769769 DOI: 10.1016/j.envpol.2016.10.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/30/2016] [Accepted: 10/08/2016] [Indexed: 05/27/2023]
Abstract
Wildlife lead exposure is an increasing conservation threat that is being widely investigated. However, for some areas of the world (e.g., South America) and certain species, research on this subject is still scarce or only local information is available. We analyzed the extent and intensity of lead exposure for a widely distributed threatened species, the Andean Condor (Vultur gryphus). We conducted the study at two different scales: 1) sampling of birds received for rehabilitation or necropsy in Argentina, and 2) bibliographic review and extensive survey considering exposure event for the species' distribution in South America. Wild condors from Argentina (n = 76) presented high lead levels consistent with both recent and previous exposure (up to 104 μg/dL blood level, mean 15.47 ± 21.21 μg/dL and up to 148.20 ppm bone level, mean 23.08 ± 31.39 ppm). In contrast, captive bred individuals -not exposed to lead contamination- had much lower lead levels (mean blood level 5.63 ± 3.08 μg/dL, and mean bone level 2.76 ± 3.06 ppm). Condors were exposed to lead throughout their entire range in continental Argentina, which represents almost sixty percent (>4000 km) of their geographical distribution. We also present evidence of lead exposure events in Chile, Ecuador, and Peru. Lead poisoning is a widespread major conservation threat for the Andean Condor, and probably other sympatric carnivores from South America. The high number and wide range of Andean Condors with lead values complement the results for the California Condor and other scavengers in North America suggesting lead poisoning is a continental threat. Urgent actions are needed to reduce this poison in the wild.
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Affiliation(s)
- Guillermo M Wiemeyer
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina; Facultad de Ciencias Veterinarias-Universidad de Buenos Aires, Av. Chorroarín 280 (1427), C.A.B.A., Argentina; The Peregrine Fund, 5668 W Flying Hawk Lane, Boise, ID, 83709, USA; Fundación Cabure-í, Sucre 2842 9º "A" (1428), C.A.B.A., Argentina.
| | - Miguel A Pérez
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina
| | - Laura Torres Bianchini
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina; Facultad de Ciencias Veterinarias-Universidad de Buenos Aires, Av. Chorroarín 280 (1427), C.A.B.A., Argentina
| | - Luciano Sampietro
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina; Facultad de Ciencias Veterinarias-Universidad de Buenos Aires, Av. Chorroarín 280 (1427), C.A.B.A., Argentina
| | - Guillermo F Bravo
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina
| | - N Luis Jácome
- Fundación Bioandina Argentina, República de la India 3000 (1425), C.A.B.A., Argentina
| | - Vanesa Astore
- Jardín Zoológico de la ciudad de Buenos Aires, República de la India 3000 (1425), C.A.B.A., Argentina; Fundación Bioandina Argentina, República de la India 3000 (1425), C.A.B.A., Argentina
| | - Sergio A Lambertucci
- Grupo de Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (CONICET-Universidad Nacional del Comahue), Quintral 1250, Bariloche 8400, Argentina
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Naidoo V, Wolter K, Botha CJ. Lead ingestion as a potential contributing factor to the decline in vulture populations in southern Africa. ENVIRONMENTAL RESEARCH 2017; 152:150-156. [PMID: 27771569 DOI: 10.1016/j.envres.2016.10.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 10/12/2016] [Accepted: 10/14/2016] [Indexed: 05/27/2023]
Abstract
Vulture populations in southern Africa have been on the decline for years, which unlike the Asian vulture crisis, has no one specific cause. Reasons attributable are deliberate and secondary poisonings, drowning, power line injuries, electrocutions, traditional medicine ("muti" trade) and calcium deficiencies. However, lead toxicity as a potential causal factor is hardly mentioned. The potential for lead toxicity needs to be considered as substantial game hunting occurs in the region with little regulatory control on bullet types. In this study, we determined the whole blood lead concentrations of captive and wild vulture populations in South Africa and Namibia (n=185). Results were compared to previous published ranges indicative of background exposure (<10μg/dL), non-toxic point exposure based upon the range established from captive birds and subclinical exposure. In general, whole blood lead concentrations were higher for wild African White-backed vultures (Gyps africanus)(AWBV) than Cape vultures (G. coprotheres)(CGV) at 15.54±12.63μg/dL vs 12.53±8.88μg/dL (non-significantly different), while in the Bearded vultures (Gypaetus barbatus) no indication of exposure was evident. Very similar exposures resulted irrespective of the birds being in captivity or under wild, free-roaming conditions. A proportion of wild birds did, however, appear to be exposed to another source of lead than purely environmental (±12% and 30.6% for AWBV and CGV respectively). One bird, which had a whole blood concentration of 100μg/dL, died soon after capture. To find the relationship between whole blood lead concentration and likely exposure factors, birds were compared by their rural/urban location, vicinity to mines and surrounding soil lead concentrations. With no relationship being present for the latter factors, we believe that this is evidence that the portion of southern African vultures being exposed to unknown source of lead, which we suggest arises from leaded ammunition remaining from hunting.
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Affiliation(s)
- V Naidoo
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa.
| | - K Wolter
- Vulture Programme (VulPro), Plot 121, Rietfontein 0048, South Africa
| | - C J Botha
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
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Multi-locus phylogenetic inference among New World Vultures (Aves: Cathartidae). Mol Phylogenet Evol 2016; 105:193-199. [PMID: 27601346 DOI: 10.1016/j.ympev.2016.08.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 08/09/2016] [Accepted: 08/31/2016] [Indexed: 11/23/2022]
Abstract
New World Vultures are large-bodied carrion feeding birds in the family Cathartidae, currently consisting of seven species from five genera with geographic distributions in North and South America. No study to date has included all cathartid species in a single phylogenetic analysis. In this study, we investigated the phylogenetic relationships among all cathartid species using five nuclear (nuc; 4060bp) and two mitochondrial (mt; 2165bp) DNA loci with fossil calibrated gene tree (27 outgroup taxa) and coalescent-based species tree (2 outgroup taxa) analyses. We also included an additional four nuclear loci (2578bp) for the species tree analysis to explore changes in nodal support values. Although the stem lineage is inferred to have originated ∼69 million years ago (Ma; 74.5-64.9 credible interval), a more recent basal split within Cathartidae was recovered at ∼14Ma (17.1-11.1 credible interval). Two primary clades were identified: (1) Black Vulture (Coragyps atratus) together with the three Cathartes species (Lesser C. burrovianus and Greater C. melambrotus Yellow-headed Vultures, and Turkey Vulture C. aura), and (2) King Vulture (Sarcoramphus papa), California (Gymnogyps californianus) and Andean (Vultur gryphus) Condors. Support for taxon relationships within the two basal clades were inconsistent between analyses with the exception of Black Vulture sister to a monophyletic Cathartes clade. Increased support for a yellow-headed vulture clade was recovered in the species tree analysis using the four additional nuclear loci. Overall, these results are in agreement with cathartid life history (e.g. olfaction ability and behavior) and contrasting habitat affinities among sister taxa with overlapping geographic distributions. More research is needed using additional molecular loci to further resolve the phylogenetic relationships within the two basal cathartid clades, as speciation appeared to have occurred in a relatively short period of time.
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Fayiga AO, Saha UK. Soil pollution at outdoor shooting ranges: Health effects, bioavailability and best management practices. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 216:135-145. [PMID: 27254770 DOI: 10.1016/j.envpol.2016.05.062] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 04/09/2016] [Accepted: 05/23/2016] [Indexed: 05/11/2023]
Abstract
The total lead (Pb) concentrations of the surface soil, sub surface soil, vegetation and surface waters of outdoor shooting ranges are extremely high and above regulatory limits. Lead is dangerous at high concentrations and can cause a variety of serious health problems. Shooters and range workers are exposed to lead dust and can even take Pb dust home to their families while some animals around the shooting range can ingest the Pb bullets. The toxicity of Pb depends on its bioavailability which has been determined to be influenced greatly by the geochemical properties of each site. The bioavailability of Pb in shooting ranges has been found to be higher than other metal contaminated soils probably because of its very low residual Pb (<1%). Despite being an immobile element in the soil, migration of Pb within shooting ranges and offsite has been reported in literature. Best management practices to reduce mobility of Pb in shooting ranges involve an integrated Pb management program which has been described in the paper. The adoption of the non-toxic "green bullet" which has been developed to replace Pb bullets may reduce or prevent environmental pollution at shooting ranges. However, the contaminated soil resulting from decades of operation of several shooting ranges still needs to be restored to its natural state.
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Affiliation(s)
- A O Fayiga
- The University of Georgia, 2300 College Station Road, Athens, GA 30602, USA.
| | - U K Saha
- The University of Georgia, 2300 College Station Road, Athens, GA 30602, USA
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Meyer CB, Meyer JS, Francisco AB, Holder J, Verdonck F. Can Ingestion of Lead Shot and Poisons Change Population Trends of Three European Birds: Grey Partridge, Common Buzzard, and Red Kite? PLoS One 2016; 11:e0147189. [PMID: 26799815 PMCID: PMC4723309 DOI: 10.1371/journal.pone.0147189] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 12/30/2015] [Indexed: 11/30/2022] Open
Abstract
Little is known about the magnitude of the effects of lead shot ingestion alone or combined with poisons (e.g., in bait or seeds/granules containing pesticides) on population size, growth, and extinction of non-waterbird avian species that ingest these substances. We used population models to create example scenarios demonstrating how changes in these parameters might affect three susceptible species: grey partridge (Perdix perdix), common buzzard (Buteo buteo), and red kite (Milvus milvus). We added or subtracted estimates of mortality due to lead shot ingestion (4–16% of mortality, depending on species) and poisons (4–46% of mortality) reported in the UK or France to observed mortality of studied populations after models were calibrated to observed population trends. Observed trends were decreasing for partridge (in continental Europe), stable for buzzard (in Germany), and increasing for red kite (in Wales). Although lead shot ingestion and poison at modeled levels did not change the trend direction for the three species, they reduced population size and slowed population growth. Lead shot ingestion at modeled rates reduced population size of partridges by 10%, and when combined with bait and pesticide poisons, by 18%. For buzzards, decrease in mean population size by lead shot and poisons combined was much smaller (≤ 1%). The red kite population has been recovering; however, modeled lead shot ingestion reduced its annual growth rate from 6.5% to 4%, slowing recovery. If mortality from poisoned baits could be removed, the kite population could potentially increase at a rapid annual rate of 12%. The effects are somewhat higher if ingestion of these substances additionally causes sublethal reproductive impairment. These results have uncertainty but suggest that declining or recovering populations are most sensitive to lead shot or poison ingestion, and removal of poisoned baits can have a positive impact on recovering raptor populations that frequently feed on carrion.
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Affiliation(s)
| | - Joseph S. Meyer
- Arcadis, Lakewood, Colorado, United States of America
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, Colorado, United States of America
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Golden NH, Warner SE, Coffey MJ. A Review and Assessment of Spent Lead Ammunition and Its Exposure and Effects to Scavenging Birds in the United States. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 237:123-191. [PMID: 26613991 DOI: 10.1007/978-3-319-23573-8_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Nancy H Golden
- U.S. Fish and Wildlife Service, 5275 Leesburg Pike, Falls Church, VA, 22041, USA.
| | - Sarah E Warner
- U.S. Fish and Wildlife Service, 505 Science Drive, Madison, WI, 53717, USA
| | - Michael J Coffey
- U.S. Fish and Wildlife Service, Crab Orchard National Wildlife Refuge, 4503 West DeYoung, Suite 102, Marion, IL, 62959, USA
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Straub MH, Kelly TR, Rideout BA, Eng C, Wynne J, Braun J, Johnson CK. Seroepidemiologic Survey of Potential Pathogens in Obligate and Facultative Scavenging Avian Species in California. PLoS One 2015; 10:e0143018. [PMID: 26606755 PMCID: PMC4659623 DOI: 10.1371/journal.pone.0143018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 10/29/2015] [Indexed: 11/18/2022] Open
Abstract
Throughout the world, populations of scavenger birds are declining rapidly with some populations already on the brink of extinction. Much of the current research into the factors contributing to these declines has focused on exposure to drug residues, lead, and other toxins. Despite increased monitoring of these declining populations, little is known about infectious diseases affecting scavenger bird species. To assess potential infectious disease risks to both obligate and facultative scavenger bird species, we performed a serosurvey for eleven potential pathogens in three species of scavenging birds in California: the California condor (Gymnogyps californianus), turkey vulture (Cathartes aura) and golden eagle (Aquila chrysaetos). California condors were seropositive for avian adenovirus, infectious bronchitis virus, Mycoplasma gallisepticum, avian paramyxovirus-2, West Nile virus (WNV) and Toxoplasma gondii. Golden eagles were seropositive for avian adenovirus, Chlamydophila psittaci and Toxoplasma gondii, and turkey vultures were seropositive for avian adenovirus, Chlamydophila psittaci, avian paramyxovirus-1, Toxoplasma gondii and WNV. Risk factor analyses indicated that rearing site and original release location were significantly associated with a positive serologic titer to WNV among free-flying condors. This study provides preliminary baseline data on infectious disease exposure in these populations for aiding in early disease detection and provides potentially critical information for conservation of the endangered California condor as it continues to expand its range and encounter new infectious disease threats.
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Affiliation(s)
- Mary H. Straub
- Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Terra R. Kelly
- Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Bruce A. Rideout
- Wildlife Disease Laboratories, San Diego Zoo Institute for Conservation Research, Escondido, California, United States of America
| | - Curtis Eng
- Los Angeles Zoo and Botanical Gardens, Los Angeles, California, United States of America
| | - Janna Wynne
- California Science Center Foundation, Los Angeles, California, United States of America
| | - Josephine Braun
- Wildlife Disease Laboratories, San Diego Zoo Institute for Conservation Research, Escondido, California, United States of America
| | - Christine K. Johnson
- Wildlife Health Center, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- * E-mail:
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Kelly TR, Poppenga RH, Woods LA, Hernandez YZ, Boyce WM, Samaniego FJ, Torres SG, Johnson CK. Causes of mortality and unintentional poisoning in predatory and scavenging birds in California. Vet Rec Open 2014; 1:e000028. [PMID: 26392875 PMCID: PMC4562445 DOI: 10.1136/vropen-2014-000028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 09/30/2014] [Accepted: 10/06/2014] [Indexed: 11/06/2022] Open
Abstract
Objectives We documented causes of mortality in an opportunistic sample of golden eagles, turkey vultures and common ravens, and assessed exposure to several contaminants that have been found in carrion and common prey for these species. Methods Dead birds were submitted for testing through wildlife rehabilitation centres and a network of wildlife biologists in California from 2007 to 2009. Results The leading causes of mortality in this study were collision-related trauma (63 per cent), lead intoxication (17 per cent) and anticoagulant rodenticide poisoning (8 per cent). Elevated liver lead concentration (≥2 µg/g) and bone lead concentration (>6 µg/g) were detected in 25 and 49 per cent of birds tested, respectively. Approximately 84 per cent of birds tested had detectable rodenticide residues. The majority of rodenticide exposure occurred in peri-urban areas, suggesting that retail sale and use of commensal rodent baits, particularly in residential and semi-residential areas in California, may provide a pathway of exposure. Conclusions Monitoring anthropogenic causes of mortality in predatory and scavenging bird species provides important data needed to inform on mitigation and regulatory efforts aimed at reducing threats to these populations.
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Affiliation(s)
- Terra R Kelly
- Wildlife Health Center, School of Veterinary Medicine, University of California , Davis, California , USA
| | - Robert H Poppenga
- California Animal Health Food and Safety Laboratory System , University of California , Davis, California , USA
| | - Leslie A Woods
- California Animal Health Food and Safety Laboratory System , University of California , Davis, California , USA
| | - Yvette Z Hernandez
- Wildlife Health Center, School of Veterinary Medicine, University of California , Davis, California , USA
| | - Walter M Boyce
- Wildlife Health Center, School of Veterinary Medicine, University of California , Davis, California , USA
| | | | - Steve G Torres
- California Department of Fish and Wildlife, Wildlife Investigations Laboratory , Rancho Cordova, California , USA
| | - Christine K Johnson
- Wildlife Health Center, School of Veterinary Medicine, University of California , Davis, California , USA
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Gremse F, Krone O, Thamm M, Kiessling F, Tolba RH, Rieger S, Gremse C. Performance of lead-free versus lead-based hunting ammunition in ballistic soap. PLoS One 2014; 9:e102015. [PMID: 25029572 PMCID: PMC4100882 DOI: 10.1371/journal.pone.0102015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 06/12/2014] [Indexed: 12/02/2022] Open
Abstract
Background Lead-free hunting bullets are an alternative to lead-containing bullets which cause health risks for humans and endangered scavenging raptors through lead ingestion. However, doubts concerning the effectiveness of lead-free hunting bullets hinder the wide-spread acceptance in the hunting and wildlife management community. Methods We performed terminal ballistic experiments under standardized conditions with ballistic soap as surrogate for game animal tissue to characterize dimensionally stable, partially fragmenting, and deforming lead-free bullets and one commonly used lead-containing bullet. The permanent cavities created in soap blocks are used as a measure for the potential wound damage. The soap blocks were imaged using computed tomography to assess the volume and shape of the cavity and the number of fragments. Shots were performed at different impact speeds, covering a realistic shooting range. Using 3D image segmentation, cavity volume, metal fragment count, deflection angle, and depth of maximum damage were determined. Shots were repeated to investigate the reproducibility of ballistic soap experiments. Results All bullets showed an increasing cavity volume with increasing deposited energy. The dimensionally stable and fragmenting lead-free bullets achieved a constant conversion ratio while the deforming copper and lead-containing bullets showed a ratio, which increases linearly with the total deposited energy. The lead-containing bullet created hundreds of fragments and significantly more fragments than the lead-free bullets. The deflection angle was significantly higher for the dimensionally stable bullet due to its tumbling behavior and was similarly low for the other bullets. The deforming bullets achieved higher reproducibility than the fragmenting and dimensionally stable bullets. Conclusion The deforming lead-free bullet closely resembled the deforming lead-containing bullet in terms of energy conversion, deflection angle, cavity shape, and reproducibility, showing that similar terminal ballistic behavior can be achieved. Furthermore, the volumetric image processing allowed superior analysis compared to methods that involve cutting of the soap blocks.
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Affiliation(s)
- Felix Gremse
- Experimental Molecular Imaging, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Oliver Krone
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Mirko Thamm
- Experimental Molecular Imaging, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Fabian Kiessling
- Experimental Molecular Imaging, University Hospital, RWTH Aachen University, Aachen, Germany
| | - René Hany Tolba
- Laboratory Animal Science, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Siegfried Rieger
- Wildlife Biology, Management and Hunting Practice, HNE Eberswalde, Eberswalde, Germany
| | - Carl Gremse
- Wildlife Biology, Management and Hunting Practice, HNE Eberswalde, Eberswalde, Germany
- * E-mail:
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29
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Abstract
Free-living raptors are frequently presented to wildlife rehabilitation centers. Conditions affecting the gastrointestinal tract can be the primary reason for presentation. The gastrointestinal tract can also be affected secondary to debilitation from other injuries or from the stress of the rehabilitation process. A thorough understanding of the anatomy, physiology, and natural history of these species is crucial to successful treatment and rehabilitation. This article addresses raptor gastroenterology with an emphasis on conditions affecting free-living birds.
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30
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Reading RP, Kenny DE, Fitzgerald KT. The crucial contribution of veterinarians to conservation biology. Top Companion Anim Med 2013; 28:131-4. [PMID: 24331552 DOI: 10.1053/j.tcam.2013.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Conservation biology is a relatively new (began in the 1980s), value-based discipline predicated on the belief that biological diversity-from genes to populations to species to communities to ecosystems-is good and extinction is bad. Conservation biology grew from the recognition that the Earth has entered its sixth great extinction event, one that differs from previous great extinctions in that a single species-Homo sapiens-has caused this biodiversity crisis. A diverse, interacting set of variables drive current extinctions. As such, to succeed, conservation efforts usually require broad-based, interdisciplinary approaches. Conservationists increasingly recognize the importance of contributions by veterinary science, among many other disciplines, to collaborative efforts aimed at stemming the loss of biodiversity. We argue that, to improve success rates, many wildlife conservation programs must incorporate veterinarians as part of an interdisciplinary team to assess and address problems. Ideally, veterinarians who participate in conservation would receive specialized training and be willing to work as partners as part of a larger team of experts who effectively integrate their work rather than work independently (i.e., work as interdisciplinary, as opposed to multidisciplinary, teams, respectively). In our opinion, the most successful and productive projects involve interdisciplinary teams involving both biological and nonbiological specialists. Some researchers hold multiple degrees in biology and veterinary medicine or the biological and social sciences. These experts can often offer unique insight. We see at least 3 major areas in which veterinarians can immediately offer great assistance to conservation efforts: (1) participation in wildlife capture and immobilization, (2) leadership or assistance in addressing wildlife health issues, and (3) leadership or assistance in addressing wildlife disease issues, including using wildlife as sentinels to identify new and emerging diseases or epidemics of old diseases. We cover each of these main topics in detail.
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Affiliation(s)
- Richard P Reading
- Department of Conservation Biology, Denver Zoological Foundation, Denver, CO, USA.
| | - David E Kenny
- Department of Conservation Biology, Denver Zoological Foundation, Denver, CO, USA
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31
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Johnson CK, Kelly TR, Rideout BA. Lead in ammunition: a persistent threat to health and conservation. ECOHEALTH 2013; 10:455-64. [PMID: 24419669 DOI: 10.1007/s10393-013-0896-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 12/11/2013] [Indexed: 05/11/2023]
Abstract
Many scavenging bird populations have experienced abrupt declines across the globe, and intensive recovery activities have been necessary to sustain several species, including the critically endangered California condor (Gymnogyps californianus). Exposure to lead from lead-based ammunition is widespread in condors and lead toxicosis presents an immediate threat to condor recovery, accounting for the highest proportion of adult mortality. Lead contamination of carcasses across the landscape remains a serious threat to the health and sustainability of scavenging birds, and here we summarize recent evidence for exposure to lead-based ammunition and health implications across many species. California condors and other scavenging species are sensitive indicators of the occurrence of lead contaminated carcasses in the environment. Transdisciplinary science-based approaches have been critical to managing lead exposure in California condors and paving the way for use of non-lead ammunition in California. Similar transdisciplinary approaches are now needed to translate the science informing on this issue and establish education and outreach efforts that focus on concerns brought forth by key stakeholders.
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Affiliation(s)
- C K Johnson
- Wildlife Health Center, School of Veterinary Medicine, University of California, 1089 Veterinary Medicine Drive, Davis, CA, 95616, USA,
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32
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Bellinger DC, Burger J, Cade TJ, Cory-Slechta DA, Finkelstein M, Hu H, Kosnett M, Landrigan PJ, Lanphear B, Pokras MA, Redig PT, Rideout BA, Silbergeld E, Wright R, Smith DR. Health risks from lead-based ammunition in the environment. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:A178-9. [PMID: 23732085 PMCID: PMC3672933 DOI: 10.1289/ehp.1306945] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Affiliation(s)
- David C. Bellinger
- Harvard Medical School, Harvard School of Public Health, Boston, Massachusetts
| | - Joanna Burger
- Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, New Jersey
| | - Tom J. Cade
- Department of Ecology and Evolutionary Biology (Emeritus), Cornell University, Ithaca, New York
| | - Deborah A. Cory-Slechta
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, New York
| | - Myra Finkelstein
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California
| | - Howard Hu
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Michael Kosnett
- Division of Clinical Pharmacology & Toxicology, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Philip J. Landrigan
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Bruce Lanphear
- Child & Family Research Institute, BC Children’s Hospital, Simon Fraser University, Vancouver, British Columbia, Canada
| | - Mark A. Pokras
- Wildlife Clinic, Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts
| | - Patrick T. Redig
- The Raptor Center, Veterinary Clinical Sciences, University of Minnesota, St. Paul, Minnesota
| | - Bruce A. Rideout
- Wildlife Disease Laboratories, Institute for Conservation Research, San Diego Zoo Global, San Diego, California
| | - Ellen Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Robert Wright
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Donald R. Smith
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, E-mail:
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Bedrosian B, Craighead D, Crandall R. Lead exposure in bald eagles from big game hunting, the continental implications and successful mitigation efforts. PLoS One 2012; 7:e51978. [PMID: 23284837 PMCID: PMC3526477 DOI: 10.1371/journal.pone.0051978] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 11/14/2012] [Indexed: 11/19/2022] Open
Abstract
Studies suggest hunter discarded viscera of big game animals (i.e., offal) is a source of lead available to scavengers. We investigated the incidence of lead exposure in bald eagles in Wyoming during the big game hunting season, the influx of eagles into our study area during the hunt, the geographic origins of eagles exposed to lead, and the efficacy of using non-lead rifle ammunition to reduce lead in eagles. We tested 81 blood samples from bald eagles before, during and after the big game hunting seasons in 2005-2010, excluding 2008, and found eagles had significantly higher lead levels during the hunt. We found 24% of eagles tested had levels indicating at least clinical exposure (>60 ug/dL) during the hunt while no birds did during the non-hunting seasons. We performed driving surveys from 2009-2010 to measure eagle abundance and found evidence to suggest that eagles are attracted to the study area during the hunt. We fitted 10 eagles with satellite transmitters captured during the hunt and all migrated south after the cessation of the hunt. One returned to our study area while the remaining nine traveled north to summer/breed in Canada. The following fall, 80% returned to our study area for the hunting season, indicating that offal provides a seasonal attractant for eagles. We fitted three local breeding eagles with satellite transmitters and none left their breeding territories to feed on offal during the hunt, indicating that lead ingestion may be affecting migrants to a greater degree. During the 2009 and 2010 hunting seasons we provided non-lead rifle ammunition to local hunters and recorded that 24% and 31% of successful hunters used non-lead ammunition, respectively. We found the use of non-lead ammunition significantly reduced lead exposure in eagles, suggesting this is a viable solution to reduce lead exposure in eagles.
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Kelly TR, Bloom PH, Torres SG, Hernandez YZ, Poppenga RH, Boyce WM, Johnson CK. Impact of the California lead ammunition ban on reducing lead exposure in golden eagles and turkey vultures. PLoS One 2011; 6:e17656. [PMID: 21494329 PMCID: PMC3071804 DOI: 10.1371/journal.pone.0017656] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 02/06/2011] [Indexed: 11/18/2022] Open
Abstract
Predatory and scavenging birds may be exposed to high levels of lead when they ingest shot or bullet fragments embedded in the tissues of animals injured or killed with lead ammunition. Lead poisoning was a contributing factor in the decline of the endangered California condor population in the 1980s, and remains one of the primary factors threatening species recovery. In response to this threat, a ban on the use of lead ammunition for most hunting activities in the range of the condor in California was implemented in 2008. Monitoring of lead exposure in predatory and scavenging birds is essential for assessing the effectiveness of the lead ammunition ban in reducing lead exposure in these species. In this study, we assessed the effectiveness of the regulation in decreasing blood lead concentration in two avian sentinels, golden eagles and turkey vultures, within the condor range in California. We compared blood lead concentration in golden eagles and turkey vultures prior to the lead ammunition ban and one year following implementation of the ban. Lead exposure in both golden eagles and turkey vultures declined significantly post-ban. Our findings provide evidence that hunter compliance with lead ammunition regulations was sufficient to reduce lead exposure in predatory and scavenging birds at our study sites.
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Affiliation(s)
- Terra R Kelly
- School of Veterinary Medicine, Wildlife Health Center, University of California Davis, Davis, California, United States of America.
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