A Threatened Species
In 1741, sea otters were hunted all up the west coast of British Columbia for their fur pelts. By 1911, there were less than 2000 sea otters in the whole world! Sea otters were once extirpated in Canada, but have now successfully been reintroduced. 
www.defenders.org/.../marine/otters/faqs.html
To protect sea otters, a treaty was signed by Japan, Russia, Britain (for Canada), and the United States.  While the mammals were slowly recovering, oil spills were killing many of them.  When oil gets in their fur, they can become hypothermic and die. There can also be contamination by ingestion of the oil.
www.cyber-sisters.org./gpages/otters/
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