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Improved reproductive success in otters (Lutra lutra), grey seals (Halichoerus grypus) and sea eagles (Haliaeetus albicilla) from Sweden in relation to concentrations of organochlorine contaminants
2012
Roos, Anna M. | Bäcklin, Britt-Marie V.M. | Helander, Björn O. | Rigét, Frank F. | Eriksson, Ulla C.
We studied indices of reproductive outcome in three aquatic species in relation to organochlorine concentrations during four decades. In female otters, the frequency of signs of reproduction increased after 1990. In grey seals, pregnancy rate increased 1990–2010 and uterine obstructions ceased after 1993. The frequency of uterine tumours was highest 1980–2000. The number of sea eagle nestlings per checked nest increased 1985–2000, while the frequency of desiccated eggs decreased. Organochlorine concentrations decreased at annual rates between 3.5 and 10.2%. The estimated mean concentration (mg/kg lw) for total-PCB decreased from 70 to 8 (otters), from 110 to 15 (seals) and from 955 to 275 (eagles). The corresponding concentrations for ΣDDT decreased from 3.4 to 0.2 (otters), from 192 to 2.8 (seals) and from 865 to 65 (eagles). This study adds evidence to support the hypothesis that PCBs and DDTs have had strong negative effects on the reproduction and population levels of these species.
اظهر المزيد [+] اقل [-]Lead exposure and poisoning in bald eagles and golden eagles in the Canadian prairie provinces
1999
Wayland, M. | Bollinger, T. (Environment Canada, Prairie and Northern Region, 115 Perimeter Road, Saskatoon, SK, S7N 0X4, Canada)
Organochlorines in sea otters and bald eagles from the Aleutian Archipelago
1997
Estes, J.A. | Bacon, C.E. | Jarman, W.M. | Norstrom, R.J. | Anthony, R.G. | Miles, A.K. (National Biological Service, A-316 Earth and Marine Sciences Building, University of California, Santa Cruz, CA 95064 (USA))