Hair Mercury Concentrations in Western Hudson Bay Polar Bear Family Groups.
Methylmercury is one of the more toxic forms of mercury (Hg), the biomagnification of which is prevalent in the Arctic where apex predators such as polar bears (Ursus maritimus) can carry high loads. The maternal transfer of contaminants to offspring is a concern, as offspring may be particularly sensitive to the effects of environmental pollutants during early development. However, few studies of polar bears report on Hg in dependent young. We examined hair total Hg (THg) concentrations in 24 polar bear family groups in western Hudson Bay: mother, cub-of-the-year (COY), yearling, and 2 year old. THg concentrations increased with bear age, with COYs having lower concentrations than other offspring groups (p ≤ 0.008). Using AICc-based regression models, we found maternal THg to be positively related to body condition and litter size, while overall offspring THg was positively related to maternal body condition in addition to being dependent on the sex and age of the offspring. COY THg concentrations were positively related to maternal THg while also depending on the sex of the offspring. Considering our results, future studies in polar bear ecotoxicology are encouraged to include offspring of different ages and sexes.
Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2E9, Canada.
Thea
T
Bechshoft
Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2E9, Canada.
Andrew E
AE
Derocher
Wildlife Research Division, Science and Technology Branch, Environment and Climate Change Canada, University of Alberta , CW405, Biological Sciences Building, Edmonton, AB T6G 2E9, Canada.
Evan
E
Richardson
Wildlife Research Division, Science and Technology Branch, Environment and Climate Change Canada, University of Alberta , CW405, Biological Sciences Building, Edmonton, AB T6G 2E9, Canada.
Nicholas J
NJ
Lunn
Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2E9, Canada.
Vincent L
VL
St Louis
D000818:Animals; D061006:Bays; D006197:Hair / Q000737:chemistry; D008628:Mercury; D001503:Ursidae; D014874:Water Pollutants, Chemical
D014874:Water Pollutants, Chemical; D008628:Mercury