Steller Sea Lion
Eumetopias jubatus
At a glance
Considered the "king" of sea lions, the Steller sea lion is the biggest of all sea lions and enjoys a lifespan of up to 30 years. In Canada, the Steller can be spotted along the rocky coast of British Columbia. This hefty mammal usually travels alone or in a small group, but wisely, it joins others for protection during the mating and birthing season. Little is known about its oceanic lifestyle; however, the good news for this sea-loving mammal is that since the Steller sea lion first became protected in 1970, the size of the adult population has more than doubled.
About the Steller sea lion
Steller sea lions are carnivores with sharp teeth and strong jaws for eating their prey. They catch their own fish, eating whatever is most readily available in the area. In British Columbia, the Steller eats mainly schooling fish, such as herring, hake, sandlance, salmon and sardines. They sometimes dive deeper to catch rockfish, flounder and skate, as well as squid and octopus.
Steller sea lions are excellent swimmers, at times diving to a depth of over 350 metres in search of food, and normally remaining submerged no more than five minutes at a time.
The mating season for the Steller sea lion is between the end of May and the beginning of July. During this time, the female returns to her home rookery – an isolated rock where adults gather for mating and birthing – to give birth to a single pup. During the mating season, Stellers gather together in dense colonies for safety, away from land predators. The calls of the adults and the bleating of the newborn pups together create a loud, protective noise. This collective and constant clamour frightens off possible predators.
The female Steller sea lion nurses her pup for one to three years. The mother stays on land with her pups for one day and then goes to sea to collect food the next day. She continues this pattern to provide food for her pups, while continuing to maintain her own nourishment.
The newborn Steller is an agile little creature. It can crawl from birth and learns how to swim at around four weeks of age. Although it is fairly difficult to estimate, it seems that the mortality rate for pups is fairly high and could be a result of being trampled by older animals or in cases where they are forced off the rookery, they find themselves unable to swim and they drown.
How to recognize an Steller sea lion
The shiny-pelted Steller is called a "sea lion" because of the light mane of coarse hair found on the neck and chest of the male, resembling a lion mane. The sea lion is sometimes mistaken for the seal; however, it’s easy to tell the difference. Unlike the seal, the steller sea lion’s outer ear flaps close over its ears to protect them from water. Stellers also have a bony structure which allows them to walk on all flippers while supporting their entire weight; making them much better climbers than seals.
As the world’s largest sea lion, the adult Steller can reach lengths of two to three metres. Females weigh between 200 to 300 kilograms, while males have been found to reach up to 800 kilograms. One massive steller weighed-in at almost one tonne.
The average steller sea lion pup weighs about 20 kilograms at birth. This precocious little creature has a shiny, blackish-brown pelt. As it matures into adulthood, the pelt changes to a pale yellowish-tan colour that darkens on the underside and near the flippers.
The steller sea lion is a pinniped – literally meaning feather-footed. These amazing fins have a similar bony structure as the legs of land animals, allowing the Steller to support its entire weight while walking on them. In the water, the steller sea lion swims by using a breaststroke and can reach a top speed of about 27 kilometres an hour.
Where the Steller sea lion lives
The North Pacific dwelling Steller can be found along the coasts of California to the Bering Strait, and along the coasts of Asia and Japan. The world population is divided into two groups; the Eastern and the Western. The Canadian dwellers are part of the Eastern population.
In Canada, British Columbia’s coastal islands are home to three main breeding areas for the Steller, located in the Scott Islands, at Cape St. James and offshore from Banks Islands. About 3,400 pups were born in British Columbia in 2002. During the breeding season, the total population of animals living in these coastal waters is approximately 19,000, with about 7,600 of them being of breeding age. The most powerful males breed with several females.
Why it’s at risk
Throughout the years, human activities, such as hunting and killing have been the greatest threat to Steller sea lions. Luckily, these are also the most preventable risks.
This large creature is also prone to accidentally becoming tangled in fishing gear and may be strangled by debris around their necks. An entangled Steller could potentially drown before it can escape or be released. Pollution, oil spills and environmental contaminants like heavy metals, threaten the habitats of the Steller sea lion population. These preventable harms can lead to the relocation of the inhabitants, away from their vital dwelling places and eventually, to a decrease in their population.
The Steller sea lion also faces natural threats such as a decrease in the amount of food available. Additionally, they are subject to being hunted by killer whales. As with all animals, disease is a potential risk to the steller population.
What’s being done
Although the Steller sea lion has suffered from many years of being hunted, since 1970 it has been protected in Canada under the federal Fisheries Act which prohibits commercial hunting of the steller sea lion. There have been instances where permits have been granted for the killing of the Steller sea lion, in an attempt to protect fish farms being preyed upon by the animals.
The Oceans Act, established in 1996, protects the habitats of marine mammals. Particular breeding rookeries have the benefit of extra protection under the Canada National Parks Act and as part of a provincial ecological reserve.
The Steller sea lion is also protected in Canada as a species of special concern under the federal Species at Risk Act. A management plan for the Steller sea lion is currently being developed.
What can you do?
In order to continue the growth of this population, Steller sea lions need continued habitat protection. Learn more about the steller sea lion and be aware of human-induced threats to their survival, such as entanglement in fishing gear, water pollution and oil spills. Do your best to reduce these threats wherever possible to protect the steller sea lion’s vital habitat. Get involved with the Habitat Stewardship Program for Species at Risk (HSP) or another conservation organization.
Aquatic species at risk
Source: Fisheries and Oceans Canada