Fur seals belong to the family of eared seals. There are 9 species of fur seals, of which 1 lives in the northern hemisphere and 8 in the southern hemisphere. The northern fur seal is larger than its southern cousins. Male northern fur seals are 2 m long on average, and weigh 180-270 kg (females are smaller). They have a thick undercoat of soft fur, protected by longer coarser hair. The colour of the body varies from silver to dark brown, depending on whether it is dry or wet. Their flippers are brown, hairless and leathery. The nails of the hind flippers are used for grooming the dense fur. Northern Fur seals are noisy animals that feed on herring, pollocks, squid and floating shrimps. They breed between September and October. New-born pups have black woolly hair which is shed after 6 to 7 weeks. The entire breeding life of these seals is less than 20 years. Their life span is about 30 years.