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Northern Fur Seals















What is taxonomy?

There are than one million Northern fur seals in the Pacific ocean.  They range from Japan to Southern California and north through out the Bering sea.  Fur seals will spend months at a time at sea.  Interestingly, during breeding season, 3/4 of the total world population will be found on the Pribilof Islands.  The bulls will normally stay for four months, the females for six months.  The bulls vigorously protect their territory and can lose 1/4 their body weight in doing so.  A large bull Northern fur seal can weigh 600 pounds and a large female 110 pounds.

Interesting Facts:

  • A Northern fur seal bull, that has territory, will defend it against any intruding bulls, and even humans!!
  • The Northern fur seal can spend extremely long periods in the open ocean.  Before returning to the breeding colonies many pups will remain at sea for up to 22 months!
  • A Northern fur seal mother find her pup by moving thru the breeding colony and listening for the pup's distinctive voice!
  • Northern fur seals mainly feed at night, when prey species are closer to the ocean surface!
  • Northern fur seals have huge flippers, proportionally bigger than a Steller sea lions.  They help keep them cool.
  • Northern fur seals are famous for the dense fur that that covers all but their flippers.  That fur consists of approximately 46,500 hairs per square centimeter. 

What I should know about Northern fur seals!

Where do Northern fur seals live?

Northern fur seals range extends from Southern California, up the North American coast, West along the Alaskan coastline, across the sub Arctic sea to the Russian coast and down to waters of northern Japan. 

How many Northern fur seals are there?

The estimate of the worlds population of Northern fur seals is 1,130,000.  There are about 880,000 northern fur seals in U.S. waters and most breed on the Pribilof Islands. A smaller population of Northern fur seals are found on San Miguel Island of the California coast. But in 1909, there were only 200,000 to 300,000 left to breed on the Pribilof Islands because of commercial seal harvests.  The seal hunters harvested the Northern fur seals for their fur.

How can I identify a Northern fur seal?

Males are gray to black, and females are light gray on the back and reddish-brown on the chest with a light patch.  Both have extremely dense fur, so dense that it keeps the cool ocean water from the skin, thereby preserving body heat; but it is not waterproof.  Because of this dense fur they have large, hairless flippers to keep them cool.  The females weigh 90 to 110 pounds on average, and the males between 300 and 615 pounds.  Like all fur seals and sea lions, the Northern fur seal has ears that stick out from its head.  By rotating their flippers forward, they can walk, run and climb out of the water.

What do Northern fur seals eat?

Northern fur seals feed mainly at night and may dive to depths of 600 feet (180 m) in search of small schooling fish and squid and prey are typically eaten underwater.  Larger fish are brought to the surface and eaten there.

How do Northern fur seals have their young?

After giving birth on one of the rookeries, the mother nurses her pup for 8-10 days.  She then begins a pattern of leaving to feed at sea for 4 to 10 days, and returning for 1 or 2 to nurse her pup. During this time she usually makes short shallow dives at night to feed. The pups are weaned after 4 months.

How long do Northern fur seals live? How do they die?

The Northern fur seal can live for 25 years, but most females live to be 18-20 years old and the males to their low teens.

Natural predators of the fur seals include sharks, foxes, killer whales and Steller sea lions. El Ñino and entanglement also are hazardous to the Northern fur seal.

Where can I find more information about Northern fur seals?

Go back.

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