The sea otter is a marine mammal in the weasel family. They are also on the endangered species list. At one time there was an estimated population of 200,000 to 300,000 sea otters living along the Pacific coast of North America. In the 1700's through to the early 1900's they were extensively hunted for their fur and by 1911 there was only about 1000 to 2000 left in the world. Thankfully conservation efforts, as well as an international ban on hunting has allowed the sea otter populations to rebound but loss of habitat and competition with humans for food are still a concern for those who wish to preserve this wonderful species.