The population of Northern sea otters living in the waters off south Alaska (pictured herewith) has thankfully stabilized despite thousands of sea otters perishing in Prince William Sound as a result of the 1989 Exxon Valdez oil spill. Rebuilding the population took about 25 years. The U.S. Geological Survey (USGS) published a 2014 report concluding that the population had recovered to pre-spill levels.