Thursday, August 5, 2010

Study Shows Toxins Affect Polar Bears, Gulls, other Arctic Wildlife

A recently published report uses new data on the effects of persistent organohalogen contaminants (OHCs) on Arctic wildlife to evaluate health risks of a range of species, including polar bears, killer whales and black-backed gulls.

The study, created for the Arctic Monitoring and Assessment Program, looked at OHC contamination in relation to other stressors like disease, predation, climate change, food scarcity, and body condition, to see how contaminants affect species at a population level.

For the Arctic's top predator, the research findings:
have highlighted that OHCs adversely affect polar bear liver and kidney functions, immune response and endocrine system, which helps regulate growth, cognitive abilities, and body temperature. These impairments may alter the ability for bears to acclimatize and adapt to extreme Arctic environments.

When these effects are considered in combination with climate change, natural periods of fasting, cub survival rate, and female reproductive impairment, polar bear populations in East Greenland and Svalbard may be at higher risk of chronic population-level stress.
Studies of other species found similar trends. The effects of certain OHCs on great black-backed gulls from northern Norway, for example, appeared to have been aggravated when the birds were exposed to parasites, climate change, and food scarcity, among other things.

More details from this study are summarized in Environment Canada's quarterly newsletter, Wildlife and Landscape Science News, which, incidentally, I always find an interesting read.

0 comments: