Seals
At least four seal species, the Weddell seal, Crabeater seal, Leopard seal and Ross seal use sea ice as a resting and hunting platform, as a place to give birth or as a refuge from predators.
Weddell Seals
(Leptonychotes weddelli) are named after James Weddell a sealer who in 1823 reached the most southerly point in the sea which is also named after him. They live in areas of constant sea ice cover, mostly fast ice. In order to breathe and to haul out the Weddell seal maintains holes in the ice by biting and rasping the ice with its incisors and canine teeth. Weddell seals eat fish and squid which they find at depths exceeding 500 meters. They can dive for up to 70 minutes. Weddell seals grow up to 3 meters long and may weigh 500 kg. In October they give birth to a single pup.
Crabeater seals
Crabeaters (Lobodon carcinophagus) are smaller than Weddell seals and live mainly in open water near the ice edge or in the pack ice where they also give birth to their young. As their name denotes, they feed mainly on krill "crabs". For this purpose they possess a special serrations on their teeth which act as a sieve through which they can squeeze the water engulfed together with the krill. Crabeater seals may occur in large groups and are probably the most numerous of all seals world-wide. It is estimated that their krill consumption exceeds that of the wales. Because of their small size, Crabeaters are often preyed upon by killer whales. Those lucky enough to escape recover on the sea ice as the picture shows.
Leopard Seal
The leopard seal (Hydrurga leptonyx) is a voracious predator living off penguins and small seals. However, it also consumes krill. Leopard seals attain a length of 4 m and weigh up to 500 kg. Due to their slender shape and smooth fur they are nevertheless agile swimmers. They are solitary animals which never congregate into large groups, even when they give birth to their young on the ice.
Ross seal
This fourth seal species (Ommatophoca rossi) is small and seldom seen because it occurrs in mostly inaccessable pack ice regions. Very little is known about this seal. Up to 1970 only 200 had been recorded.