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Steller Sea Lions

The Steller sea lion is the largest species of sea lion in the world, with adult males reaching a length of almost 11 feet and a weight of up to 2,400 pounds.

The Steller sea lion (Eumetopias jubatus) is the largest of all sea lions. It has a range that extends across the North Pacific Ocean, from Northern California up to Alaska and across the Bering Sea to Russia and Japan. Their population is divided between a western stock, which extends from Japan to Prince William Sound in Alaska, and an eastern stock, which extends from Alaska down to California.

The western population of Steller sea lions was listed as endangered under the Endangered Species Act in 1997, at the same time that the eastern population was listed as threatened. The eastern population of Steller sea lions was as low as 18,000 in the late 1970s, although it has recovered considerably since then, reaching an estimated population of 70,000 in 2010. As a result of this, the eastern stock was taken off the Endangered Species List in October, 2013.


"These beasts are indeed terrible to look upon when alive; and they far surpass the sea bear in strength and size as well as in endurance of the different parts. They are hard to overcome and fight most viciously when cornered. They also give to the eyes and mind the impression of a lion."
          Georg Wilhelm Steller, 18th century German naturalist

The Steller sea lion gets its name from naturalist Georg Wilhelm Steller, who traveled from Russia to Alaska with Vitus Bering’s Second Kamchatka Expedition in 1740-1742. Steller was the first European to set foot in Alaska and his observations of the natural world formed the basis for De Bestiis Marinis (On the Beasts of the Sea), his chronicle of the voyage. Steller identified six species of birds and mammals during the expedition, including the Steller sea lion, Steller's Eider, Steller's Sea Eagle, Steller's Jay, Steller's sea cow, and the Spectacled Cormorant. The first three are endangered or threatened while the latter two are extinct. Only the Steller's Jay is not currently endangered.

The Marine Mammal Center rarely has Steller sea lion patients, for a number of reasons. They usually haul out in very remote locations, their population in California is less than 1,000, and California is at the southern limit of their range. Since 1975, we have rescued a total of 27 Steller sea lions, most of them orphaned or abandoned pups. Among these were Astro and Artemis, both of whom were rescued on Año Nuevo Island.

Astro, a
Steller sea lion

Astro was only a few days old when he was rescued by The Marine Mammal Center. He was spotted by a researcher on Año Nuevo Island, alone and with no mother in sight. Volunteers bottle-fed him fish formula until he was old enough to eat whole fish and after 10 months at the Center he was released back to the ocean. Sea lions that are rescued at such a young age can have a difficult time adapting to the wild, however, because they easily become habituated to human beings. Astro had to be rescued two more times after he returned to populated areas. Finally he was given a new home at The Mystic Aquarium in Connecticut where he now happily resides.


In November, 2014, a young Steller sea lion pup was found stranded, alone on a beach in Ocean Shores, Washington. The pup was brought to PAWS Wildlife Center in Lynnwood, Washington for temporary care and later transferred to the Center, where he could get the best care possible. Named Leo, this pup stayed at the Center for five months and rapidly grew into a big healthy animal. He gained 150 pounds during his stay at the Center, while he learned how to catch live fish and socialize with other sea lions and fur seals. Once Leo was healthy and strong, he was released near the location of his original rescue in Washington state. He had a satellite tracking device attached to the fur on his head, so that researchers could collect data on his behavior in the wild.

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