Steller Sea Lion
By: Rosie Ros
Stellerís sea lion, or northern sea lion, is the major member of the family of eared seals Otariidae. A bull Stellerís sea lion weighs an average of 1,300 pounds and measures around eleven feet long, and a female average at 600 pounds and nine feet. They were illustrate and named by German naturalist Georg Wilhelm Steller who sailed with Vitus Bering on his voyages to the Bering Sea and North American coast of the Pacific. Stellerís sea lions range from the northern islands of the Japanese archipelago north to the Bering Straits, and south along the coast to northern California. Stellerís sea lions are greedy predators, feeding on Pollock, flounder, herring, capelin, Pacific cod, salmon, rockfish, sculpins, squid and octopus. They are quarry only to killer whales, large sharks, and humans. Early people of the north Pacific coast depended heavily on them for food, clothing, and boat coverings. The estimated populations of Stellerís off Alaska declined from 242,000 animals in the early 1970s to less than half of that now. Their impressive decline is the subject of intense study and is possibly the result of many factors including disease, ecological change, natural predation on juveniles, and the activities of marketable fishing fleets. Stellerís sea lions are listed as a threatened species under the endanger Species Act.
Their center of abundance has been in the Aleutian Islands and Gulf of Alaska where traditionally nearly three-fourths of all Steller sea lions inhabiting U.S. province were found. Two populations are currently recognized. The western population, positioned from Prince William Sound Alaska westward, has declined by about 85% since the 1970s for reasons that are poorly understood.
However, they appear to be related to at least in part to prey availability. The eastern population, located east of Prince William Sound appears to be recovering slowly. Steller sea lions haulout on land to mate, bear their young, nurse, avoid predators, and rest. The location of rookeries is probably based on proximity to food sources, protection from terrestrial and marine predators, topography, surf conditions, and other factors.
Steller sea lions are generally considered nonmigratory although some individuals, predominantly juveniles and adult males, may disperse widely outside the summer breeding season. Most adult sea lions return to their birth site for reproduction.The life time of this lion is 20-30 years.
Rosieros is an expert author, who is presently working on the site about Sea Lion and Sea Boss . He has written many articles in various topics. For more information Ocean Animals.
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