DANIELS: FKKDING ECOLOGY OF ANTARCTIC FISHES 





g George I. 



Q„Joinville I. 



100 200 km 



Figure 1.— Antarctic Peninsula showing sites where major collections of fish were made, 1975: Low Island (1), Dallmann Bay (2), 

 The Sound, Melchior Islands (3), Port Lockroy (4), Arthur Harbor, site of Palmer Station (5), Peltier Channel (6), Paradise Harbor (7), 

 Argentine Islands (8), Adelaide Island (9), Square Bay (10), and Terra Firma Islands (11). 



(SL)), weighed, and dissected. Stomachs were 

 removed, opened, and all contents flushed onto 

 petri dishes. Prey items were sorted, counted, 

 and assigned a point volume (Hynes 1950). One 

 point is approximately equivalent to an isopod 

 Munna sp. with an approximate volume of 0.25 

 ml and approximate dimensions of 15 X 5 X 3 

 mm; one point was also approximately equivalent 

 to 2 mg dry weight. To test the accuracy of the 

 estimated volumes, the contents of 60 stomachs 

 of Harpagifer bispinis were assigned a point 

 volume, volume was measured by displacement, 

 and the contents were dried and weighed. There 

 was little difference between the three measure- 

 ments (Friedman's Test, 0.2<P<0.3) (Langley 

 1970). Individual pieces of algae were not 

 counted and were excluded from all calculations 



involving number of prey items consumed. 



The feeding and foraging behavior of eight 

 species were observed in tanks at Palmer Station 

 and on 140 scuba dives. Twenty-two dives were 

 specifically planned to observe feeding and 

 foraging behavior. In the laboratory, observa- 

 tions were made on recently collected fishes 

 which were introduced into a small cage in a 

 tank where several species of invertebrates were 

 established. The tanks had a gravel substrate, 

 larger rocks, and algae. Invertebrates included 

 in the tanks were scaleworms (Harmothoe 

 spinosa), amphipods (Bovallia gigantea, Eury- 

 inera monticulosa), isopods (Scrolls polita, Munna 

 sp., Cymodocea antarctlca), molluscs (Patlnlgera 

 polarls, Margarella antarctlca, Trophon sp., 

 Neobuccinum eatoni), and echinoderms (Stere- 



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