McKenna: Trophic relationships of Antarctic demersal fish of South Georgia Island 



647 



Results 



Krill and fish were the dominant items in the diets of 

 these fish (Table 2). In addition to these items, 26 types 

 of invertebrates and plant material were represented 

 in the guts (Sponges, Ctenophores, Cnidarians, Neme- 

 ratines, Nematodes, Bivalves, Cephalopods, Picno- 

 gonids, Cumacids, Tanaids, Copepods, Mysids, Bryo- 

 zoans, and Echinoderms accounted for less than 1% of 

 the diet). Of the 321 stomachs examined, 26 were 

 discarded because they were not properly preserved, 

 30 were empty, and 13 contained only unidentifiable 

 material. The highest proportion of unidentifiable 



material (among the stomachs used in the similarity 

 anaysis) was 48% (on a wet weight basis) and occurred 

 in Artedidraco minis (Table 3). The ratio of dry weight 

 to wet weight of unidentifiable material averaged 22%. 

 This is within the range of values for identifiable prey 

 items in the diets and was most similar to the same 

 ratio for fish (Table 4). Despite the problems of dif- 

 ferential digestion, it was assumed that the proportions 

 of identifiable material were accurate representations 

 of the diet of these fish. 



Every species examined ate some krill (Table 2). 

 However, most pairwise comparisons of species diets 



