(Gray, 1872) - Subantarctic fur seal
Distinctive Characteristics
In both sexes, the muzzle is moderate to short, flat, and somewhat pointed, with a non-bulbous nose and forward pointing nostrils. The vibrissae are very long, often reaching past the ears and well down the chest. The long ear pinnae, with naked tips, lie close to the head and are not particularly prominent. The flippers are proportionately short and broad. Adult males are heavily built; their enlarged chest and shoulders make the neck appear short. They develop a prominent tuft, or crest, of long guard hairs on top of the head, and a thick mane. In adult females, the mane and crest are absent, but the fur is generally longest on the chest and neck. Adult females have a blunt, broad muzzle.
Subantarctic fur seals are strikingly marked. In adult males, the back colour varies from greyish or orangish brown to charcoal (males become increasingly grizzled with age). There is often a dark band between the flippers, but the rest of the belly is a lighter brown. Adult females are usually lighter grey on the back than are bulls. In both sexes, the colour of the chest, muzzle, and face (to the ears and above the eyes) is cream to burnt orange. The tops of the flippers and the area around their insertions are brown, usually darker than the rest of the back (although, sometimes paler in bulls). The dark colour on the head sometimes comes to a forward-facing point on the muzzle. The naked ear tips are usually dark.
The dental formula is I 3/2, C 1/1, PC 6/5.
Can be confused with
Subantarctic fur seals co-occur with Antarctic, South American, South African, Australian, New Zealand, and Juan Fernandez fur seals, and South American sea lions. Distinguishing fur seals may be problematic, except for adult males, but note size, coloration, muzzle length, size of nose, relative flipper size, and vibrissae colour and length.
Size
Adult males are up to 1.8 m long and weigh 70 to 165 kg, females 1.4 m and 25 to 55 kg. Newborns are about 60 cm and 4 to 4.4 kg.
Geographical Distribution
Subantarctic fur seals are widely distributed in the Southern Hemisphere. They breed on many subantarctic islands north of the Antarctic Convergence. The northern limit of their range is not well known, but vagrants have appeared in South Africa, Argentina, Brazil, Australia, and the Juan Fernandez Islands. Subantarctic fur seals have also been recorded south of the convergence at South Georgia. When ashore, these seals prefer rough, rocky terrain.
Biology and Behaviour
Subantarctic fur seals pup and breed from late October to early January, with a peak in mid-December. Seals also are ashore for the annual moult between February and April, with a peak in March and April.
Little is known of their behaviour while at sea. Except for cows with pups, most of the population spends much of the winter and spring (June-September) at sea.
Diet varies by location and season, with fish, squid, penguins, and krill predominating.
Exploitation
Subantarctic fur seals were heavily hunted in the late 18th and 19th Centuries. Breeding groups on most islands were hunted out and the seals disappeared from a number of localities. Most colonies are experiencing rapid growth at present.
IUCN Status
Insufficiently known.