FISHERY BULLETIN: VOL. 80, NO. 3 



Table 7.— Seasonal dietary changes in fishes of sim ilar size collected at the same locale off the Antarctic 

 Peninsula. 1975. A \* test for association was used to examine changes in the volume of each taxon con- 

 sumed. A Wilcoxon sum of ranks test was used to examine changes in feeding intensity. 



Table 8.— Percentage diet similarity by number of prey items consumed (upper triangle) and point 

 volume (lower triangle) in fishes taken off the Antarctic Peninsula, 1975. 



among similar species is often present. Results 

 from other studies, using fewer species, are 

 similar (Permitin and Tarverdiyeva 1972, 1978; 

 DeWitt and Hopkins 1977; Richardson 1975; 

 Moreno and Osorio 1977; Moreno and Zamorano 

 1980). This high diversity is attributable to diet 

 changes with size of fish, capture locality, and 

 season. 



The harpagiferids, bathydraconids, and chan- 

 nichthyids tend to be more specialized than the 

 nototheniids in both their choice of prey and in 

 the method used to obtain it. Results for Har- 

 pagifer bispinis can be compared to those of 

 Meier (1971), Richardson (1975), and Wyanski 

 and Targett (1981). In all cases, H. bispinis was 

 shown to consume amphipods overwhelmingly. 

 Artedidraco skottsbergi consumed polychaetes 

 and amphipods; similar results were reported by 

 Wyanski and Targett (1981). No comparable 

 data are available for the bathydraconids or the 

 channichthyids examined in this study. How- 

 ever, the diets of the five channichthyids exam- 



ined by Permitin and Tarverdiyeva (1972, 1978) 

 show them to be specialized feeders and, with the 

 exception of C. aceratus, planktivorous; my re- 

 marks regarding the diets of P. macropterus and 

 Cryodraco antarcticus corroborate these find- 

 ings. 



The high degree of dietary similarity that I ob- 

 served among certain fishes and the similarity of 

 diets reported by Permitin and Tarverdiyeva 

 (1972, 1978), and Richardson (1975) do not 

 necessarily imply interspecific competition over 

 food, but do suggest a complex trophic structure 

 not normally associated with communities of 

 high latitudes (Cushing 1975). The benthic fishes 

 studied use a wide variety of mechanisms to 

 assure a constant food supply. For the general- 

 ists, these include switching prey types and 

 feeding strategies; the specialists consume prey 

 types which are themselves capable of maintain- 

 ing stable populations either by switching food 

 by becoming inactive (Dearborn 1967) or by 

 possessing a reproductive biology which in- 



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