Northern Fur Seals have a body length up to 2.1 m (7 ft) and they weigh between 50 and 270 kgs (110 - 600 lbs).
Males are much larger than females and they are coloured dark grey or reddish brown. Females are coloured grey/brown and pups are black.
Northern Fur Seals can be found throughout the north Pacific Ocean.
Northern Fur Seals feed on fish and squid.
Northern Fur Seals have a gestation period of 11 - 12 months, which includes a 4 month period of delayed implantation, and they give birth to a single pup. The pup is weaned at 4 months old and they reach sexual maturity at 3 - 6 years of age.