FISHERY BULLETIN: VOL. 79, NO. 4 



the brittle star, Amphipholis squamata. Mollusca 

 constituted 9.8'7r of the diet by weight. The sea 

 scallop, Placopecten magellanicus; the soft-shell 

 clam, Mya arenaria; and the cockle, Cerastoderma 

 pinnulatum, were noteworthy. Polychaetes formed 

 a small portion of the diet. A large amount of 

 bottom sediment and organic material was found 

 in the stomachs examined. 



Little Skate 



Thirty-one prey taxa were found in the 33 little 

 skate stomachs. The little skate fed primarily on 

 crustaceans (Table 6). The decapods were the most 

 important group, making up 50.7% of the diet by 

 weight. Crangon septemspinosa and Cancer ir- 

 roratus were principal prey species. Amphipods 

 were next in importance with L. pinguis, Unciola 

 sp., and Monoculodes sp. as significant prey items. 

 The remaining crustacean groups did not consti- 

 tute a substantial part of the diet. Polychaetes 

 were the next major prey group, accounting for 

 10.1% of the diet by weight. Porifera, Nematoda, 

 and Pisces were of minor importance. 



Table 6. — Stomach contents of 33 little skates ranging from 

 25.6 to 55.2 cm (mean 39.6 ±10.1 cm) and 71 to 1,194 g (mean 

 496 ±346 g). There were no empty stomachs. IRI = index of 

 relative importance (see text). 



Percentage 



Taxon 



Weight Number Frequency' 



IRI 



Porifera total 0.15 



Nematoda total .08 



Polychaeta total 10.14 



Crustacea total 66.89 



Mys(dacea total .19 



Mysis mixta . 1 3 



Other Mysidacea .06 



Cumacea total .08 



Amphipoda total 15.80 



Ampelisca agassizi .06 



Leptocheirus pinguis 5.01 



Unciola sp. 1.37 



Pontogenia inermis .08 



Anonyx sarsi 2.38 



Monoculodes sp. 2.42 



Other Amphipoda 4.48 



Decapoda total 50 71 



Crangon septemspinosa 1 8.51 



Cancer irroratus 22.68 



Other Decapoda 9.52 



Isopoda total .11 



Pisces total .67 



Detritus 1 .60 



Remains 20.47 



Grand total 100.00 



000 



4.17 



17 



94 78 



1.22 



.70 



52 



1.22 



70 78 



1.04 



24.17 



12.52 



1,57 



3.13 



24.52 



3.83 



21.39 



9.22 



9.39 



2.78 



,17 



.87 



100.00 



303 

 15.15 

 36,36 

 9697 



6.06 



15,15 

 84.85 



9.09 

 66.67 

 51.52 

 12 12 



9.09 

 57 58 



78 79 

 57.58 

 36.36 



3.03 



15.15 







64 



375 



15,677 



20 

 7,347 



10 



1,946 



716 



20 



50 

 1,551 



5.680 

 1,596 

 1,166 



1 

 23 



'Frequency of occurrence of food item. 



Atlantic Cod 



The 75 Atlantic cod stomachs contained a total 

 780 



of 30 prey taxa. Crustaceans were the major prey 

 group, accounting for 40.3% of the diet by weight 

 and 98.5% of the diet by number (Table 7). Am- 

 phipods. especially Unciola sp. and L. pinguis, 

 were most heavily preyed upon. The decapods 

 made up 18.2% of the diet by weight, with Cran- 

 gon septemspinosa and Cancer irroratus as princi- 

 pal prey. The mysids, notably Mysis mixta, were 

 next in importance. Cumaceans and isopods made 

 up a negligible portion of the diet. Pisces were the 

 next major group and constituted 14.6% of the diet 

 by weight. Other phyla (Nematoda, Polychaeta, 

 Mollusca, and Echinodermata) were of little im- 

 portance. A large amount of unidentifiable re- 

 mains (40.9% of the diet by weight) was found in 

 the stomachs examined. 



Table 7, — Stomach contents of 75 Atlantic cod ranging from 

 15.0 to 53,6 cm (mean 22,5 ±5.5 cm) and 27 to 1,555 g (mean 

 128±195 gi. Ten stom.achs were empty. IRI = index of relative 

 importance (see text). 



Percentage 



Taxon 



Weight Number Frequency' 



IRI 



Nematoda total 0.00 



Polychaeta total 1 .06 



Mollusca total ,02 



Crustacea total 40,27 



Mysidacea total 4.00 



Mysis mixta 2,45 



Other Mysidacea 1,55 



Cumacea total ,07 



Isopoda total 1,01 



Cirolana polita 1 .01 



Other Isopoda ,00 



Amphipoda total 16,98 



Ampelisca agassizi .51 



Leptocheirus pinguis 2.44 



Unciola sp, 11,13 



Pontogenia inermis .12 



Hippomedon serratus .45 



Aeginella longicornis .05 



Other Amphipoda 2.25 



Decapoda total 18.21 



Crangon septemspinosa 9.06 



Cancer irroratus 6.07 



Other Decapoda 3.08 



Echinodermata total 1,94 



Pisces total 14,61 



Detritus 1,17 



Remains 40,94 



Grand total 100,00 



0,35 



,35 



,43 



98 45 



8,46 



7.42 



1.04 



1.04 



.43 



.35 



.08 



8585 



10,01 



3.80 



66.01 



1.21 



1.55 



.69 



2.58 



2.67 



1.55 



,26 



.86 



.17 



.26 



100.00 



4.00 

 12.00 



1.33 

 84.00 

 3867 

 2533 



5.33 

 5,33 

 4.00 



72.00 

 2,67 

 21,33 

 58.67 

 10.67 

 12.00 

 6.67 



24.00 



13.33 



4.00 



1.33 

 5.33 



1 



17 



1 



11,652 



481 



250 



6 

 8 

 5 



7,404 



28 



133 



4,528 



14 



24 



5 



501 



141 



25 



3 

 79 



' Frequency of occurrence of food item. 



Red Hake 



Twenty-four prey taxa were found in the 30 red 

 hake stomachs. The red hake fed principally upon 

 crustaceans, and this group accounted for 72.4% of 

 the diet by weight (Table 8). Amphipods were the 

 most important order with L. pinguis, Unciola sp., 

 and Ampelisca agassizi as significant prey items. 

 Decapods were also heavily preyed upon and 



