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stocks of southern sperm whales, he reviews stock identi- 

 fication research including blood typing (Gushing et al., 

 1963), morphometry (Clarke and Poliza, 1972; and Machin, 

 1974) and whale mark recoveries. Gulland (1974) noted the 

 well known phenomenon that only male sperm whales are found 

 in polar areas, and suggested that this unexplained sexual 

 segregation may be a social factor since he found no clearly 

 identified food type differences in tropical and polar 

 waters. Commercial sperm whaling yielded the highest 

 catches from whaling statistical areas II, III, and IV — 

 similar to baleen whaling. Again, it is not known if this 

 high level is due to increased effort or other factors. 



b. Killer Whale 



Killer whales are relatively small but highly predatory 

 whales found all around Antarctica which may hunt in packs 

 in excess of 25. They reputedly attack whales, seals, and 

 birds, but, according to Erickson and Hofman (1974) , their 

 main food items are fish and squid. Although Siniff and 

 Bengtson (1977) attribute the predominance of crabeater seal 

 scars to leopard seals rather than killer whales, the authors 

 hypothesize that killer whales probably take crabeater seals 

 successfully, and hence leave no scars. 



C. Antarctic Seals 



Seals play important ecological roles in the Antarctic 

 marine ecosystem. Those found south of the Convergence in- 

 clude the four true Antarctic seals of the subfamily 

 Lobodontinae : crabeater, Weddell, leopard, and Ross as well 

 as the southern elephant seal and southern fur seals. Recent 

 reviews on Southern Ocean seals include those by Erickson 

 and Hofman (1974), Laws (1977a, 1977b), Gilbert and Erickson 

 (1977), and 0ritsland (1977). Information on the distribution, 

 movements, stock identification, standing stock, and food 

 habits of these seals follows. 



1. True Antarctic Seals 



Accounts of the ecology and biology of the four true 

 Antarctic seals are found in papers on 1) crabeater seals 

 (Wilson, 1907; Lindsey, 1938; Bertram, 1940; Laws, 1958, 1964, 

 1977a, 1977b; 0ritsland, 1970b; Erickson and Hofman, 1974; 

 Siniff et al., 1977a, 1978); 2) Weddell seals (Bertram, 

 1940; Stirling, 1969c, 1971a, 1971b; Siniff et al., 1971, 

 1974, 1977b; Erickson and Hofman, 1974; Kaufman et al., 

 1974; DeMaster, 1978); 3) leopard seals (Wilson, 1907; 

 Brown, 1957; Hamilton, 1939; Marlow, 1967b; Penney and 

 Lowry, 1967; Erickson and Hofman, 1974; Hofman et al., 1977); 

 and 4) Ross seals (Erickson et al., 1973). 



