Stellar Sea Lions Essay, Research Paper
Stellar Sea Lion
Stellar sealion (Eumetopias Jubatus). Stellar sea lions are sometimes confused with
California sea lions, but are alot larger and lighter in color. Males may grow to eleven feet
in length and weigh almost 2,500 pounds. Females are much smaller, and may grow to
nine feet in length and 770 pounds. Stellar sea lions are light tan to reddish brown in color.
They have a flat face and a boxy, bare-like head. “Adult males lack the saggital crest that
adult male California sea lions display.” Stellars have a bulky build and a very thick neck.
Stellar sea lions are found throughout the north pacific rim from Japan to central
California. Stellars tend to stay offshore or move out to unpopulated areas.
Breeding occurs along the north pacific rim from ano nuero island in central
california to the kuril islands north of alaska and aleutian islands. Pups are born on
offshore islands from midmay to mid July and weigh 35-50 puonds. Mothers stay wth
pups for one to two weeks before hunting at sea. Then they spend tiume hunting and
nurishing pups on land. Pups usually nurse for a year, but some continue to nurse up to
three years. Breeding occurs 10-14 days after the pups are born. Dominat males maintain
territorys for one to two months and breed with many females. During the breeding
season, males do not eat.
Stellar sea lions eat a variety of fishes, invertebrates, and other pimmipeds. Known
predators are orca (killer whales) and white sharks. Stellars can contract many of the same
diseases as California sea lions, such as lepospirosis, and San Miguel sea lion virus.
Population The current population of the Stellar sea lions is about 40,000, with
about 500 living in California. Their population has dropped by 80% in the last 80 years.
The entire population has been listed as a threatened species since 1990, and the western
U.S. stock was listed as endangered in 1997. Reasons for this decline is because the
decline of fish due to increasing commercial fisheries. Drownling or entanglent in nets, of
intentional gunshot are all reasons for the stellars decline. Stellars are protected under the
marine mammal protection act, which prohibits the killing, harming, or harassing of any
marine mammal, as well as the endangered species act.With this protection there is hope
for the recovery of the population.
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