Fact Sheet
Northern Fur Seal

Basic Facts About Northern Fur Seals

Northern fur seals are classified as pinnipeds, a word which is derived from the Latin and means "flap-footed." Native to the northern Pacific Ocean, northern fur seals have the second thickest fur of any animal, second only to the sea otter. The coat of the adult female fur seal is a reddish brown on the front and underside with a silver patch on the chest and silver gray on their top. Adult males can range in color anywhere from brownish gray to black.

Diet

The primary diet of the fur seal consists mainly of squid, pollack, herring, salmon, mackerel, and anchovies.

Population

Did You Know?

Northern fur seals exhibit extreme sexual dimorphism, with males being 30 – 40 percent longer and more than 4.5 times heavier than adult females.

There are an estimated 1.2 million northern fur seals in the world today. The majority of fur seals, an estimated 60 - 70 percent, breed at Pribilof Islands located in the Bering Sea. Smaller rookeries are located on Bogoslof Island in the Aleutians and the Kuril Islands and Commander Islands near mainland Russia in the western North Pacific. Unfortunately over the last decade there has been a steady decline of northern seal pup births.

Range

Northern fur seals are found throughout the Northern Pacific Ocean from Japan to southern California all the way up to the Bering Sea.

Behavior

Northern fur seal males are territorial and upon arriving to the mating sites during mating season, will begin to assert their dominance and establish territories by threatening and fighting other males. These territories may contain at least 40 females.

Did You Know?

Northern fur seals spend about half of the year out at sea. They sleep on their backs while floating along the surface with their fins sticking out of the water. This is called the "jug-handle" position.

Adult males do not feed during mating season and can lose up to 20 percent of their total weight.

Northern fur seals tend to live alone or in pairs, and rarely come to land, except to breed. About half of each year is spent out at sea. Sharks, orcas, and Steller sea lions will all hunt northern fur seals if they get the opportunity.

Reproduction

Mating Season: Summer, with peak in late June
Gestation: 11-12 months
Litter size: One pup

More on Northern Fur Seal: Threats to Northern Fur Seals »

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