Crabeater
seal. Photo by B. Clements
© Copyright Australian Antarctic Division
Crabeater seals (Lobodon carcinophagus) spend their entire lives in the pack-ice zone surrounding Antarctica. They rest, breed and moult on the pack-ice, and feed in the surrounding water.
They are by far the most abundant seal species in the southern ocean, but estimates of total abundance are highly variable, ranging from 12 to 75 million. A major international survey is planned for 1998/99 to provide a more precise estimate of total population size.
Males and females are similar in size, reaching lengths of 2.5 m and weights of 400 kg
Crabeater seals feed mainly on krill (Euphausia superba).
They are capable of diving to depths of up to 250 m, but usually feed within the upper 20 m of the water column.
Crabeater seals 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.
They breed on the ice 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.
Moulting occurs in January and February. Seals spend most of their time on the ice when moulting.
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 predation by leopard seals when they were younger.