648 



Fishery Bulletin 89(4), 1991 



showed less than 50% overlap (Tables 5,6), suggesting 

 that in most cases resource partitioning was occurring. 

 This is supported by the cluster analysis which showed 

 that there was more than one significant cluster (Figs. 

 2,3). The species or groups of species distinguished by 

 the cluster analysis were feeding on different sets of 

 prey ."There were three groups of species in the com- 

 munity: fish-eaters, krill-eaters, and benthic inverte- 

 brates feeders. 



Fish-eaters 



The four members of the fish-eating group included 

 most of the large carnivorous species in the region. The 

 diets of C. aceratus and Parachaenichthys georgianus 

 showed the greatest similarity (Figs. 2,3) within the 

 fish-eating group and overlapped by 78% (Table 6). 

 They fed predominantly on fish, but each species also 

 consumed roughly similar proportions of krill Euphau- 

 sia superba and shrimp Notocrangon antarcticus (Table 

 3). Although little is known about the life history of 

 Parachaenichthys georgianus, both it and C. aceratus 

 appear to be epibenthic in their behavior. 



Chaenocephalus aceratus is the largest species of 

 icefish found in the South Georgia region, growing up 

 to 75 cm (Fischer and Hureau 1985). It is an ambush 

 predator (Kock 1985b). Heavily calloused pelvic fins of 

 older individuals indicate that it spends much of its time 

 sitting on the bottom. Fish prey included Parachae- 

 nichthys georgianus and N. larseni, which were as 

 much as 58% of its body size (TL). 



