Endangered Species
- Endangered Home
- Why Save Species?
- Species of Concern
- Extinct Species
- Non-Endangered
- How to Help
- Act Early
Species of Special Concern
Status
Alaska species of special concern;
Federal threatened
species (population east of 144° W. Long.);
Federal endangered species
(population west of 144° W. Long.)
Description
Steller sea lions are the largest of the "eared" seals. They are light brown in color, with darker undersides and flippers. Pups are much darker at birth. Males may reach weights in excess of 1,700 pounds and have enlarged necks and noticeable manes. Females are much smaller, averaging about 570 pounds. Sea lions are at home both on land and at sea. They use their long front flippers for propulsion and their hind flippers for steering under water. On land, sea lions pull their hind flippers up under their body and "rolling walk" on all four flippers.
Habitats and Habits
Steller sea lions are highly gregarious on land and use the same sites for breeding, pupping, and resting year after year. The most well known Steller sea lion habitats are rookeries, where adult animals gather to breed and give birth from late May to early July. Steller sea lions are polygymous; dominant males mate with many females. Rookeries and haulouts (where sea lions rest and take refuge throughout the year) are usually located on relatively remote islands where access by predators is limited. Steller sea lions prey primarily upon schooling fishes, such as pollock and herring, as well as invertebrates, such as squid and octopus. They can be found throughout the North Pacific Ocean from the Kuril Islands and Okhotsk Sea, through the Aleutian Islands and Bering Sea, and south along the North American coast to central California. About 70 percent of the worldwide Steller sea lion population resides in Alaska.
Causes of Decline
Counts of Steller sea lions on rookeries and major haulouts between the mid-1970s and the present indicate about a 70 percent decline in the Alaska portion of the population. The causes of the decline are unknown but may include disease, environmental change, and the effects of commercial fisheries, including direct mortality and reduction in the availability of sea lion food. Recent population surveys show that the decline is continuing. The 1989 estimate for the Alaska portion of the Steller sea lion population is approximately 64,000 animals.
Range of Steller Sea LionResearch and Recovery
Since 1990, steps have been taken to reduce sea lion mortality and restrict disturbance of sea lions, especially at rookeries. These steps include prohibitions on shooting at or near sea lions by any other than Alaska Native subsistence hunters, restrictions on how close vessels can get to rookeries, limits on the unintentional harvest of sea lions by commercial fishers, and fishery closures around some rookery sites. Research on the causes of the decline is continuing, and a plan to promote the recovery of the species has been prepared.
Text: Susan Mello
For Additional Information
Please contact:
Doug Vincent-Lang
(907) 267-2339
