H-21 



RESEARCH PROGRAMMES 



(a) Crabeater Seal. 



The Crabeater Seal is the most abundant seal in the Antarctic and probably in the world. 

 Siniff and others (1970) and Erickson and others (1971) have shown a relationship between ice 

 type, in terms of cover and density, and Crabeater Seal abundance. The largest numbers of 

 Crabeater Seals are to be found in small ice floe environments covering between 30 and 70 per 

 cent of the water surface. The Crabeater Seal has a 24-hour activity pattern with peak numbers 

 hauled out, it is thought, at local apparent noon; research is needed to document what the 

 proportion may be. The food of the Crabeater Seal is mainly krill, mostly Euphausia superba, 

 though there is a possibility that the bulk of the food will be E. crystallorophias in some areas 

 over the shelf. 



PLATE 3. A Crabeater Seal family group. 



Little is known about the breeding of the Crabeater Seal since it occurs in the austral spring 

 when the ice is at its maximum (Laws, 1958; 0ritsland, 1970). After weaning, the pups 

 probably disperse and form groups in the pack ice. Hofman (1975), Lindsey (1937) and 

 Bertram (1940) suggest that the young of the year congregate along the edge of the Antarctic 

 continent in areas where the ice is quite dense. This leads to a segregation by sex and age, the 

 older, mature animals being at the periphery of the pack ice with the younger animals toward 

 the interior (Hofman, 1975). The maximum recorded age for a Crabeater Seal is 33 years, little 

 is known about mortahty, although the Killer Whale and Leopard Seal are known to feed on 

 this species. Predation would appear to be significant since a high proportion of Crabeater Seals 

 observed in the pack ice are scarred. 



(b) Leopard Seal. 



The Leopard Seal is the largest of the true Antarctic seals, it appears that it is catholic in its 



