Steller Sea Lion

Eumetopias jubatus
PROFILE Stellers 520x289

Steller Sea Lions are the largest members of the Otariidae family—the so-called eared seals—comprising some 15 species worldwide. Whereas sea lions and their ilk sport external ear flaps known as pinnae, Harbor Seals and other members of Phocidae (the “true seals”) lack such structures. The eared seals’ family name derives from the Greek otarion, meaning “little ear”.

Named after Wilhelm Steller (a German naturalist whose appellation also appends those of a jay and an extinct sirenian), these enormous pinnipeds inhabit the Pacific from Japan to southern California. Those found in Oregon tend to remain offshore or haul out on unpopulated beaches, distinguishable from afar (and from other pinnipeds) by their golden fur and basso roar. The main haul-out areas along the Oregon coast are Rogue Reef, Three Arch Rocks—visible from Cape Meares NWR—and Shell Island.

Steller Sea Lions breed in Oregon during the months of June and July. Off our southern coast, Rogue and Orford reefs—both part of Oregon Islands NWR—support the largest Steller breeding sites in U.S. waters south of Alaska, producing some 1,500 pups annually. Newborn Steller Sea Lions are dark brown to black; this thick natal coat, known as lanugo, is shed at 4- to 6-month intervals to reveal progressively lighter hair. This pattern repeats until the adult pelage, usually light tan to reddish brown, grows in.

Breeding grounds occur along the North Pacific Rim from Año Nuevo Island in central California to the Kuril Islands north of Japan, with the greatest concentration in the Gulf of Alaska and the Aleutian Islands. Beginning in 1997, biologists separated Steller Sea Lions into two distinct populations: Eastern and Western. The Western population resides in the north Pacific from roughly south-central Alaska west to Russia; the Eastern, from panhandle Alaska to northern California. Both were federally listed as threatened under the Endangered Species Act in 1990. The Western population remains threatened, but in December 2013 the Eastern population was deemed sufficiently recovered to warrant de-listing.

According to an October 2013 press release from the fisheries department of the National Oceanic and Atmospheric Administration, populations of Eastern Steller Sea Lion “increased from an estimated 18,040 animals in 1979 to an estimated 70,174 in 2010, the most recent year for which data are available.” In U.S. waters, the species continues to enjoy certain immunities under the Marine Mammal Protection Act, and will retain such status in perpetuity.

Facts About Steller Sea Lion

-Adult males lack a visible sagittal crest (the bump on the top of their heads) as is found on adult male California Sea Lions

-Fish, such as herring, cod and pollock, constitute dietary bulk; octopus, squid, and the pups of other marine mammals supplement these

-Adult males can grow to almost 2500 pounds and 11 feet in length; adult females weigh up to 770 pounds and stretch to 9.5 feet

-Recovery of Eastern population has put pressure on commercial fisheries: on the Columbia River, rubber bullets are used by officials to deter Steller Sea Lions from eating salmonid smolts