The Steller’s Sea Lion

Ralph LaPlant

These Steller’s Sea Lions were photographed in a rookery located in a fjord south of Seward, Alaska. Being gregarious (sociable), this animal is decreasing in numbers throughout much of its range. Ralph LaPlant Photo
These Steller’s Sea Lions were photographed in a rookery located in a fjord south of Seward, Alaska. Being gregarious (sociable), this animal is decreasing in numbers throughout much of its range. Ralph LaPlant Photo

 

Being “eared seals,” The Steller’s Sea Lion is that family’s largest member. Named, in part, after the German explorer of the 1700s, Georg Steller, who explored Alaska’s coastal waters, the name sea lion comes from the idea that they resemble terrestrial lions of Africa and Asia because of long heck hairs that give the shoulders an appearance of having a lion-like mane.
    Using rookeries to breed and pup, males defend these territories from May through July. Mating results in females giving birth to a single pup a year later. Pups are weaned in the first year but some may suckle for up to three. Males slightly out number females by birth and rarely are there twins born.
    The Steller’s (or Northern) Sea Lion ranges from the coast off of Northern California to the Bering Sea to off of Russia and to Japan’s coastal waters. Declining in worldwide population from 281,000 in the 1970s, the Alaska population at that time was 242,000. This Alaskan population decreased 50% in the 1970s trough the 80s. This was due, in part, to commercial harvesting of sea lion pups. In 1972 the Marine Mammal Protection Act helped stifle harvesting with some still being used by Native Alaskans for food and clothing.
    Being very different in size, all sea lions weigh about 50 pounds at birth, with growth rates varying between sexes as the adult male can weigh 1,245 pounds and the adult female often weighing only 580 pounds. While being only 20% longer than females, males outweigh them two to one.
    Being marine carnivores, Steller’s Sea Lions eat fish including herring, salmon, rockfish, cod and others. They also eat invertebrates such as squid and octopus. Most often eaten are off-bottom schooling species.
    Due to, in part, to the Steller’s Sea Lion Recovery Team Plan, this animal is being researched. There has been a decline in populations and there is not conclusive theories, as of yet, as to why. Some predict the Steller’s Sea Lion will soon be extinct in some of its range.
Steller’s Sea Lion Facts
They can dive 650 feet for food
The dive can last 20 minutes
This deep and long dive has no negative impact on the animal
Their hind feet move forward to help with movement (a seal’s does not)
In 1989 there was an estimated worldwide population of 116,000