STELLER SEA LION BIOLOGY
Steller sea lions range from southern California, around the Pacific rim to northern Japan, but most of the world’s Steller population breeds between the central Gulf of Alaska and the western Aleutians.
Steller sea lions were listed as a threatened species under the US Endangered Species Act in 1990, and were listed as two distinct populations in 1997 (listing those east of Prince William Sound as threatened, and relisting those to the west as endangered). In 2013, the eastern stock of Steller sea lions was taken off the Endangered Species List because of significant increases in sea lion numbers.
The earliest census of Steller sea lions was done in 1956. At that time there were about 250,000 Stellers in Alaska. The population rose to a peak of about 282,000 in the mid 1970s. Since 1980 it has decreased by over 70% (roughly 5% per year) to about 42,000 animals in 2000. Most of the decline took place in the Aleutian Islands and Kodiak region. However, since 1989, the population decline appears to have slowed significantly within two subareas of these large regions — the eastern Aleutians and western Gulf of Alaska. Increases have been occurring in the smaller populations of southeast Alaska. It is not known why these changes have occurred
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