Mercury Affects Polar Bears

Study reveals how Arctic food webs affect mercury in polar bears

Published Tuesday, December 8, 2009 in Earth & Climate

http://esciencenews.com/articles/2009/12/08/study.reveals.how.arctic.food.webs.affect.mercury.polar.bears?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+eScienceNews%2Fpopular+%28e%21+Science+News+-+Popular%29&utm_content=Google+Reader

Summary:

Global warming is not the only threat to arctic animals. Mercury pollution is almost as threatening. About 150 tons of man-made mercury are put into the environment from coal-burning power plants and chlorine-producing plants, each year. It is then sent onto land or into water where it is absorbed by microorganisms such as plankton. Polar bears are at the top of their food chain and when they eat the smaller animals they consume a large mass of the mercury. Also, sea ice is melting due to global warming it forces polar bears to eat more phyto-plankton based webs. Both of these issues could cause a lot more polar bears to become more exposed to mercury and develop mercury poisoning. As Blum stated in the article,"If you want to understand the potential effects of changing ecosystems on polar bears, you need to be aware of the existence of these two food webs, which may possibly be affected by sea ice."

Opinion/Reflection:

It surprised me that the decline in polar bears was not only due to global warming. I never thought that mercury would be the cause of the decline in the population of polar bears too. I also did not know that humans are the cause of most mercury in the environment. If we stop using things that will release mercury into the air, then polar bears will less-likely die of mercury poisoning.

Questions:

1. What can we do to put less mercury into the environment?

2. What contributes to mercury in the environment?

3. What is the impact of mercury on the Arctic?

4. What are other causes of the decline in the polar bear population?

5. Why are polar bears consuming too much mercury?