![]() When they swim, Steller sea lions use their broad, long front flippers to propel themselves and are highly maneuverable. They can climb and are sometimes found on rocks or cliff faces high above the water. On land, sea lions, unlike "true" seals, can turn their hind flippers forward for walking. The flippers and other hairless parts of the skin are black. Like other pinnipeds, they molt, or shed their fur, every year.īoth sexes have long light-colored whiskers (vibrissae) on their muzzles, which they use to sense prey and feel their way underwater. The light coloration is still visible when the body is wet. Both adult males and females have light blonde to reddish brown coats that are slightly darker on the chest and abdomen. An adult male’s chest and neck are also more massive and muscular than a female’s. Adult females are 7.5 to 9.5 feet long and weigh up to 800 pounds.Īdult males are further distinguished by long, coarse hair on the chest, shoulders, and back. Adult males may be up to 11 feet long and can weigh up to 2,500 pounds. Steller sea lions are sexually dimorphic-adult males are much larger than females. Learn more about the eastern and western DPSs Protected Status Population trends for the eastern and western DPSs differ for complex reasons most simply, the difference likely results from the different kinds and magnitudes of threats the species faces throughout its range. ![]() The eastern stock increased at a rate of 4.25 percent per year (95 percent credible intervals of 3.77-4.72 percent) between 19, based on an analysis of pup counts in California, Oregon, Washington, British Columbia, and Southeast Alaska. The eastern DPS includes Steller sea lions originating from rookeries east of Cape Suckling. The North Pacific Ocean marine heatwave of 2014 - 2016 was associated with a decline of pup productivity between 2015 and 2017 in the eastern and central Gulf of Alaska, a decline in adult female survival in the eastern Aleutian Islands, Gulf of Alaska, and Southeast Alaska, and with a subsequent decline in non-pup abundance throughout the Gulf of Alaska in 2019, contrasting with a previously increasing trend until 2017. ![]() While the western DPS has been increasing slowly overall since 2003, there are strong regional differences across the range in Alaska and the population continues to decline in the central and western Aleutian Islands. Their population has decreased approximately 77 to 81 percent from the 1970s to the early 2000s. ![]() The western DPS includes all Steller sea lions originating from rookeries west of Cape Suckling (144° west longitude). Population status and trends are reported in our stock assessment reports. The two populations of Steller sea lions differ genetically and morphologically, and have contrasting population trends. Learn more about the eastern and western populations of Steller sea lions The eastern DPS has since recovered and is no longer listed, which is a significant achievement under the ESA. The western DPS remains endangered. In 1997 NOAA Fisheries recognized two distinct population segments, listing the eastern distinct population segment (DPS) as threatened and the western DPS as endangered. Indigenous peoples and settlers hunted them for their meat, hides, oil, and other products, and today sea lions are an important subsistence resource for Alaska Natives.īecause of unexplained widespread population declines in Alaska, Steller sea lions were first listed under the Endangered Species Act (ESA) in 1990. Historically, Steller sea lions were highly abundant throughout many parts of the coastal North Pacific Ocean. They also share parts of their range with another otariid: northern fur seal. Steller sea lions' impressive low-frequency vocalizations sound more like roars than California sea lions’ barks. While they are the only living member of their genus, they share parts of their range with a smaller related species, California sea lions. Steller sea lions are named for Georg Wilhelm Steller, the German surgeon and naturalist on the Bering expedition who first described and wrote about the species in 1742. The Steller (or northern) sea lion ( Eumetopias jubatus ) is the largest member of the family Otariidae, the “eared seals,” which includes all sea lions and fur seals.
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