Steller Sea Lions

George Wilhelm Steller was the naturalist aboard Vitus Bering’s 1742 exploration of Alaska [1], and the first European to step on Alaskan soil. Two marine mammals ended up with his name: the Steller’s sea cow, a cold-water relative of the manatee; and the Steller seal lion. The sea cow was driven to extinction just 26 years later, a casualty of not being afraid of humans and the tasty flavor of its flesh. Today, the sea lion in much of Alaska is equally endangered.

Steller sea lions are pinnipeds—marine mammals with flippers, not feet. Males can weigh up to 2,000 pounds; females peak at 600 pounds. Sea lions eat several kinds of fish, but mostly pollock. They range across the North Pacific from northern Japan and Siberia all the way to California. These playful but powerful animals were abundant in western Alaskan waters until quite recently.

In the 1960s, for example, an estimated 177,000 sea lions lived in the Gulf of Alaska and along the Aleutians. Commercial hunting was halted in the mid-1970s, but the population continued to drop by more than 80 percent. By 2000, a mere 34,000 survived. The western Alaska population was officially listed as endangered in 1997, while sea lion populations in Southeast Alaska [2] and farther south to California are considered threatened.

Researchers are unsure why Steller sea lions are disappearing at such an alarming rate, and there are a multitude of possible causes—including overfishing, toxic chemicals, and predation by sharks and killer whales. Most likely it is some combination of factors, but if something isn’t done, the Southwest Alaska population could be headed for extinction.

Learn more about these fascinating animals—including the latest research—at the National Marine Fisheries Service’s website (www.fakr.noaa.gov/protectedresources [3]).