Crabeater seals

Crabeater seals
Crabeater seals (Photo: Nathan Saunders)
Crabeater sealA young female crabeater sealCrabeater seal, not terribly impressed by our presence

Scientific name: Lobodon carcinophagus

Physical description

Crabeater seals have slender bodies and long snouts. Their fur ranges from dark brown to blonde, becoming lighter in summer. Males and females are similar in size, reaching lengths of 2.5 m and weights of 400 kg. New-born pups are about 1.2 m and weigh from 20 to 30 kg.

Distribution and abundance

Crabeater seals spend their entire lives in the pack-ice zone surrounding Antarctica, resting, breeding and moulting on the pack-ice, and feeding in the surrounding water.

Crabeater seals have a circumpolar distribution with an estimated population of about 15 million. They are the most abundant seal species in the southern ocean, and the most numerous of all the world’s larger animals apart from humans.  

They can move large distances through the pack-ice, due to both active movement and passive movement on drifting ice floes. They generally move southwards in spring, and northwards in autumn, with the seasonal contraction and expansion of the pack-ice.

Conservation status: least concern

Breeding

They breed on the ice in spring, from late September to early November. Females give birth to a single pup which is weaned 3–4 weeks after birth. During this time the female spends the entire time on the ice with the pup.

During the breeding season the female and pup are usually accompanied by a male which mates with the female when she comes into oestrous. The male plays no part in bringing up the pup, and the group disbands once the pup is weaned.

Diet and feeding

Despite their name, these seals don’t eat crabs, they eat krill (Euphausia superba). Their name originates from the German word, Krebs, which covers other crustacea as well as crabs. As krill is a very abundant food source, there is a large population of these seals. Crabeater seals have specially adapted teeth with extra projections, so that when they gulp in seawater they can strain out the krill.

They are capable of diving to depths of up to 250 metres, but usually feed within the upper 20 m of the water column.

Leopard seals are a major predator of crabeater seals, particularly of young pups. Most adult crabeater seals have large scars as a result of unsuccessful attacks from leopard seals when they were younger.

This page was last modified on 12 August 2010.