The Steller Sea Lion

The Steller Sea Lion

By Jade Losinski

In 1990, the Endangered Species Act listed the Eumetopias Jubatus, or Steller sea lion, as a threatened species. However, they were reclassified their Western population as 'endangered' in 1997. The Sea Lions are separated into two different groups, Western and Eastern Steller sea lions. While the Eastern population of Sea Lions has stabilized  and thrived over times the Western population of Sea Lions still continues to decline tremendously. 

Description: 

The steller sea lion is classified as a pinniped. Pinnipeds are defined as "a large group of marine mammals that are widely distributed and  a diverse group of carnivorous, fin-footed, semiaquatic animals". They are large creatures, males weighing in at an average of 1,250 pounds and females at 700 pounds and ranging from 8-11 feet long. These sea lions have a tan-ish, light brown coloring when dry - however, appear dark brown or almost black when wet. Most sea lions have a strong thick coat to shield themselves from rough terrain and cold weather. Their fur is not the only thing that protects them from extreme temperatures. Pinnipeds are known for their thick layers of blubber that insulate their bodies. 

Food:

The Steller sea lion has a diet of different sea creatures such as: walleye pollock, herring, capelin, mackerel, rockfish, and salmon; andcephalopods such as squid and octopuses. They often move from the Northern Pacifics Coasts in areas between Japan and California to hunt for their food. 

Habitat:

Steller sea lions are usually located throughout the Pacific Rim and about 70 percent of the Steller sea lion population resides in Alaska. From 1980 to 2000, more than 80% of the Steller sea lion vanished from the Gulf of Alaska and the Bering Sea. This left less than 55,000 sea lions in the once large population.

Threats to Steller Sea Lion:

Marine Biologists have had trouble finding a distinct factor causing the decline in this population. They have come to the conclusion that many different causes contribute to their endangerment. These factors include

•  Predation by killer whale (the sea lion's main predator is the killer whale)
• Declining food sources (due to over fishing by fisheries and pollution)
• Climate change affecting the ocean currents (creating dead zones, killing the ground fish that are a food source for sea lions)
• Increased diseases (sea lions become introduced to new diseases from other animals or humans they are not immune to and their genetic diversity is not strong enough to withstand the new diseases)
• Pollutants present in water (pollutants affect sea lions themselves and their prey by making them sick and introducing them to toxins)
• Human interactions and disturbances (illegal hunting, habitat destruction, etc.)
• Bycatch (accidental catching of sea creatures such as sea lions during commercial fishing)

 All of these factors contributed to the rapidly declining population of the Western portion of the Steller sea lion species. In 1997, the Endangered Species Act recognized the rapidly declining species and reclassified the species as 'endangered',

 not just 'threatened'.

Recovery Plan:

The recovery plan plays as a call to action in many ways. It stated that there should be a no entry zone to protect the animals and decrease the risk of competitive interactions between fisheries and the sea lions. Researchers have been conducting more and more research to further understand the factors involved with this declining population and the necessary preventative measures. The ESA stressed the importance of maintaining a ecosystem with ground fish and sea lions coexisting and providing for each other. Thus the fishing implications they discuss. Since the ESA has created these no entry zones, population sizes have increased slowly at about 3% per year. Since they have implemented these no entry zones hunting of sea lions for the fur and meat has decreased. This slow improvement is a step in the right direction, but more needs to be done to protect this declining population of pinnipeds.

What YOU Can Do:

There are not many things the public can do to help the recovery of these animals. Because the factors causing the endangerment are so inconclusive it is hard for the general public to change their actions. The few things we can do are to lessen our pollution and help the ESA conduct research to find a way to save this species.

Works Cited 

Alaska Fisheries Science Center. "Steller Sea Lions in Alaska: Complexity of the Problem." Steller Sea Lion Research Overview. Alaska Fisheries Science Center, 2003. Web. 04 Dec. 2015.

National Marine Fisheries Service. Recovery Plan for the Steller Sea Lion: Eastern and Western Distinct Population Segments (Eumetopias Jubatus): REVISION. N.p.: National Marine Fisheries Service, n.d. 2008. Web. 4 Nov. 2015.

National Marine Fisheries Service. Recovery Plan for the Steller Sea Lion: Eastern and Western Distinct Population Segments (Eumetopias Jubatus): REVISION. N.p.: National Marine Fisheries Service, n.d. 2008. Web. 4 Nov. 2015.

North Pacific Universities Marine Mammal Research Consortium. "Distribution." Steller Sea Lions Northern Fur Seals Marine Mammal Research Consortium Steller Sea Lion Research. North Pacific Universities Marine Mammal Research Consortium, 2014. Web. 04 Dec. 2015.

Saundry, Peter. "Steller Sea Lion." Steller Sea Lion. The Encyclopedia of Earth, 29 Oct. 2008. Web. 04 Dec. 2015.

"Steller Sea Lions, Eumetopias Jubatus." MarineBio.org. MarineBio, 2015. Web. 04 Dec. 2015.

World Wildlife Fund. "Sea Lion." World Wildlife Fund. World Wildlife Fund, 2015. Web. 4 Nov. 2015.