Fur seal

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Fur seal is a common name that does not correspond to a single taxonomic unit. For a more comprehensive discussion of all eared seals, including the sea lions, see Otariid.

Fur seals

Image:Arctocephalus Pusillus Pusillus.jpg

Cape Fur Seal

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Suborder:	Pinnipedia
Family:	Otariidae

Genera

Callorhinus
Arctocephalus

Fur seals are any of nine species of pinnipeds in the Otariidae family. One species, the northern fur seal (Callorhinus ursinus) inhabits the North Pacific, while seven species in the Arctocephalus genus are found primarily in the Southern hemisphere. They are much more closely related to sea lions than true seals, and share with them external ears (pinnae), relatively long and muscular foreflippers, and the ability to walk on all fours. They are marked by their dense underfur, which made them a long-time object of commercial hunting.

1 Taxonomy
2 Physical appearance
3 Behavior and ecology
4 Exploitation
5 Species
6 See also

[edit] Taxonomy

Until recently, fur seals were all grouped under a single subfamily of called Arctocephalinae to contrast them with Otariinae - the sea lions - based on the most prominent common feature, namely the coat of dense underfur intermixed with guard hairs. Recent genetic evidence, however, suggests that Callorhinus is more closely related to some sea lion species, and the fur seal/sealion subfamily distinction has been eliminated from most taxonomies. Nonetheless, all fur seals have certain features in common: the fur, generally smaller sizes, farther and longer foraging trips, smaller and more abundant prey items, great sexual dimorphism and a history of commercial exploitation. For these reasons, the distinction remains useful.

[edit] Physical appearance

Fur seals share with other otariids the ability to turn their rear limbs forward and move on all fours. Fur seals are generally smaller than sea lions - at under 1 m, the Galapagos fur seal is the smallest of all pinnipeds. However, their flippers tend to be proportionately longer, their pelage tends to be darker and the vibrissae more prominent. Males are often more than five times heavier than the females, making them among the most sexually dimorphic of all mammal groups.

[edit] Behavior and ecology

Fur seals gather in large herds once a year to breed on beaches or rocky outcrops. While the northern fur seal males will aggressively defend their harems. ^[1] After giving birth, females go on extended foraging trips, sometimes up to a week, returning to the rookery to feed their pups until they are weaned. Fur seals are carnivorous, feeding on fish, squid and krill. They are preyed upon by sharks, killer whales, and occasionally larger sea lions.

[edit] Exploitation

Many fur seal species were heavily exploited by commercial sealers, especially during the 19th century when their fur was highly valued. Many populations, notably the Guadalupe fur seal, northern fur seal and Cape fur seal, suffered dramatic declines and are still recovering. Currently, most species are protected and hunting is mostly limited to subsistence harvest. Globally, most populations can be considered healthy, mostly due to the fact that they often prefer remote habitats that are relatively inaccessible to humans. Nonetheless, environmental degradation, competition with fisheries and climate change potentially pose threats to some populations.

[edit] Species

SUBORDER PINNIPEDIA
Family Otariidae
- Genus Arctocephalus
  - Antarctic Fur Seal, A. gazella
  - Guadalupe Fur Seal, A. townsendi
  - Juan Fernandez Fur Seal, A. philippii
  - Galapagos Fur Seal, A. galapagoensis
  - Cape Fur Seal, A. pusillus
    - South African Fur Seal, A. pusillus pusillus
    - Australian Fur Seal, A. pusillus doriferus
  - New Zealand Fur Seal or Southern Fur Seal, A. forsteri
  - Subantarctic Fur Seal, A. tropicalis
  - South American Fur Seal, A. australis
- Genus Callorhinus
  - Northern Fur Seal, C. ursinus
- Genus Eumetopias
- Genus Neophoca
- Genus Otaria
- Genus Phocarctos
- Genus Zalophus
Family Phocidae: true seals
Family Odobenidae: Walrus