Lead poisoning and other human-related factors cause significant mortality in white-tailed eagles
The white-tailed eagle (Haliaeetus albicilla) suffered a severe population decline due to environmental pollutants in the Baltic Sea area ca. 50 years ago but has since been recovering. The main threats for the white-tailed eagle in Finland are now often related to human activities. We examined the human impact on the white-tailed eagle by determining mortality factors of 123 carcasses collected during 2000–2014. Routine necropsy with chemical analyses for lead and mercury were done on all carcasses. We found human-related factors accounting for 60% of the causes of death. The most important of these was lead poisoning (31% of all cases) followed by human-related accidents (e.g. electric power lines and traffic) (24%). The temporal and regional patterns of occurrence of lead poisonings suggested spent lead ammunition as the source. Lead shot was found in the gizzards of some lead-poisoned birds. Scavenging behaviour exposes the white-tailed eagle to lead from spent ammunition.
KeywordsDisease Finland Lead poisoning Mercury Mortality factors White-tailed eagle
We want to express our thanks to the people who submitted or reported dead or diseased white-tailed eagles suitable for this study. We warmly thank the competent staff of the Finnish Food Safety Authority, especially Minna Nylund, Perttu Koski, Nina Aalto and Annette Brockmann for their help in post-mortem examinations.
- Bevanger, K., F. Berntsen, S. Clausen, E.L. Dahl, Ø. Flagstad, A. Follestad, D. Halley, F. Hanssen, et al. 2010. Pre- and post-construction studies of conflicts between birds and wind turbines in coastal Norway (Bird-Wind). Report on findings 2007–2010. NINA Report 620, Trondheim, Norway.Google Scholar
- Burnham, K.P., and D.R. Anderson. 2002. Model selection and multimodel inference: A practical information- theoretic approach, 2nd ed. New York: Springer.Google Scholar
- Delahay, R.J., and C.J. Spray (eds.). 2015. Proceedings of the Oxford Lead Symposium. Lead Ammunition: understanding and minimising the risks to human and environmental health. Oxford: Edward Grey Institute, The University of Oxford.Google Scholar
- EFSA (European Food Safety Authority). 2013. Scientific opinion on lead in food. Retrieved 11 April, 2017, from http://www.efsa.europa.eu/en/efsajournal/pub/1570.
- Franson, C. 1996. Interpretation of tissue lead residues in birds other than waterfowl. In Environmental contaminants in wildlife—interpreting tissue concentrations, ed. W.N. Beyer, G.H. Heinz, and A.W. Redmon-Norwood, 265–279. Boca Raton, FL: CRC.Google Scholar
- Heinz, G.H. 1996. Mercury poisoning in wildlife. In Noninfectious diseases of wildlife, ed. A. Fairbrother, G.L. Hoff, and L.N. Locke, 118–127. Ames, IA: Iowa State University Press.Google Scholar
- Helander, B., and T. Stjernberg. 2002. Action Plan for the conservation of White-tailed Sea Eagle (Haliaeetus albicilla). Strasbourg: Birdlife International.Google Scholar
- HELCOM (Helsinki Commision). 2010. Hazardous substances in the Baltic Sea – An integrated thematic assessment of hazardous substances in the Baltic Sea. Baltic Sea Environment Proceedings No. 120B. Retrieved February, 2018, from http://www.helcom.fi/Lists/Publications/BSEP120B.pdf.
- Henriksson, K., E. Karppanen, and M. Helminen. 1966. High residues of mercury in Finnish white-tailed eagles. Ornis Fennica 43: 38–45.Google Scholar
- Herrmann, C., O. Krone, T. Stjernberg, and B. Helander. 2011. Population development of baltic bird species: White-tailed sea eagle (Haliaeetus albicilla). HELCOM Baltic Sea Environment Fact Sheets. Retrieved May, 2017, from http://www.helcom.fi/baltic-sea-trends/environment-fact-sheets/.
- Iwata, H., M. Watanabe, E.-Y. Kim, R. Gotori, G. Yasunaga, S. Tanabe, Y. Masuda, and S. Fujita. 2000. Contamination by chlorinated hydrocarbons and lead in Steller’s Sea-Eagle and White-tailed Eagle from Hokkaido, Japan. In First symposium on Steller’s and white-tailed eagles in East Asia, ed. M. Ueta, and M.J. McGrady, 96–106. Tokyo: Wild Bird Society of Japan.Google Scholar
- Koivusaari, J., T. Stjernberg, H. Ekblom, and J. Högmander. 2003. Daily body weight, amount of food and time of feeding of white-tailed sea eagles at Finnish winter feeding stations 1992–2000. In: SEA EAGLE 2000. Proceedings from an international conference at Björkö, Sweden, 13–17 September 2000, ed. B. Helander, M. Marquiss, and W. Bowerman. Stockholm: Swedish Society for Nature Conservation/SNF & Åtta.45 Tryckeri AB.Google Scholar
- Krone, O., N. Kenntner, A. Trinogga, M. Nadjafzadeh, F. Scholz, J. Sulawa, K. Totschek, P. Schuck-Wersig, et al. 2008. Lead poisoning in white-tailed sea eagles: causes and approaches to solutions in Germany. In Ingestion of lead from spent ammunition: Implications for wildlife and humans, ed. R.T. Watson, M. Fuller, M. Pokras, and W.G. Hunt. Boise, ID: The Peregrine Fund.Google Scholar
- Krone, O., N. Kenntner, and F. Tataruch. 2009. Gefährdungsursachen des Seeadlers. Denisia 27: 139–146 (In German).Google Scholar
- Mateo, R. 2009. Lead poisoning in wild birds in Europe and the regulations adopted in different countries. In Ingestion of lead from spent ammunition: Implications for wildlife and humans, ed. R.T. Watson, M. Fuller, M. Pokras, and W.G. Hunt. Boise, ID: The Peregrine Fund.Google Scholar
- Nuuja, I. (ed.). 2017. Merikotkien puolesta—WWF:n merikotkatyöryhmän vuosikymmenten taival. Helsinki: WWF Finland report. (For the white-tailed eagles—the journey of the WWF white-tailed eagle working group. In Finnish).Google Scholar
- OIE (World Organisation for Animal Health). 2017. Update on highly pathogenic avian influenza in animals (types H5 and H7). Retrieved December, 2017, from: http://www.oie.int/animal-health-in-the-world/update-on-avian-influenza/.
- Pain, D.J., I.J. Fisher and V.G. Thomas. 2009. A global update of lead poisoning in terrestrial birds from ammunition sources. In: Ingestion of Lead from Spent Ammunition: implications for wildlife and Humans, ed. R.T.Watson, M. Fuller, M. Pokras, and W.G. Hunt. Boise, ID: The Peregrine Fund.Google Scholar
- Redig, P.T., E.M. Lawler, S. Schwartz, J.L. Dunnette, B. Stephenson, and G.E. Duke. 1991. Effects of chronic exposure to sublethal concentrations of lead acetate on heme synthesis and immune function in red-tailed hawks. Archives of Environmental Contamination and Toxicology 21: 72–77.CrossRefGoogle Scholar
- Saurola, P., J. Valkama, and W. Velmala. 2013. The finnish bird ringing Atlas, vol. I. Helsinki: Finnish Museum of Natural History and Ministry of Environment.Google Scholar
- Stauber, E., N. Finch, P.A. Talcott, and J.M. Gay. 2010. Lead poisoning of bald (Haliaeetus leucocephalus) and golden (Aquila chrysaetos) eagles in the US Inland Pacific Northwest Region—an 18-year retrospective study: 1991–2008. Journal of Avian Medicine and Surgery 24: 279–287.CrossRefGoogle Scholar
- Stjernberg, T., J. Koivusaari, J. Högmander, T. Ollila, S. Keränen, G. Munsterhjelm, and H. Ekblom. 2009. Population size and nesting success of the White-tailed Sea Eagle (Haliaeetus albicilla) in Finland, 2007–2008. Linnut-vuosikirja 2008: 14–21. (in Finnish, English summary).Google Scholar
- Sulkava, S., R. Tornberg, and J. Koivusaari. 1997. Diet of the white-tailed eagle Haliaeetus albicilla in Finland. Ornis Fennica 74: 65–78.Google Scholar
- Tiainen, J., M. Mikkola-Roos, A. Below, A. Jukarainen, A. Lehikoinen, T. Lehtiniemi, J. Pessa, A. Rajasärkkä, et al. 2016. Suomen lintujen uhanalaisuus 2015—the 2015 red list of Finnish bird species. Helsinki: Ympäristöministeriö & Suomen ympäristökeskus.Google Scholar