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Fishery Bulletin 89(4), 199 1 



snow crab found in cod was made up of 

 juveniles (of both sexes) ranging between 

 6 and 44 mm CW. These smaller crabs 

 were found in stomachs of cod ranging 

 between 33 and 82 cm. The size range of 

 juvenile crab consumed by cod appeared 

 to broaden with cod size (Fig. 7). How- 

 ever, the pattern seems to reach a pla- 

 teau for juvenile crab above 44 mm CW; 

 larger juveniles were not found even in 

 large cod. Larger crab or alternate prey 

 species were present in the stomach con- 

 tents of cod above 82 cm. 



The relationship between the size range 

 of the two Hyas species and cod length 

 was similar to the relationship found be- 

 tween snow crab and cod (Fig. 8). The 

 size range of toad crab consumed became 

 broader as cod size increased. However, 

 no toad crab over 46 mm CW were found. 



Crab:skate size relationships 



The relationship between skate length 

 and the size of snow crab consumed ap- 

 pears different from the relationship 

 between snow crab and cod (Fig. 7 and 

 9). The size range of juvenile snow crab 

 consumed by skate is narrower, with no juve- 

 niles larger than 27 mm CW present, com- 

 pared with 44 mm CW for juvenile crabs 

 found in cod stomachs. Nevertheless, during 

 the spring of 1981, two large soft-shelled 

 male snow crab were found in skate stom- 

 achs, indicating that skate were able to feed 

 on larger snow crab (Fig. 9). 



The number of toad crab present in skate 

 stomachs was small (Fig. 9). The size range 

 consumed was narrow (5-21 mm CW) and did 

 not change with skate size. 



Size-frequency distributions 

 of crab prey 



By visual inspection, up to six distinct size- 

 classes, or molt groups, were determined for 

 snow crab found in cod stomachs (Fig. 10). 

 Five of these molt groups could be correlated 

 to molt groups determined by Robichaud et 

 al. (1989) for snow crab caught by beam 

 trawling during the same period in the same 

 area. The corresponding mean sizes for each 

 of the molt groups were 6.8, 13.9, 19.6,27.1, 

 and 37.3mm CW. Only two corresponding 

 molt groups (6.8 and 13.9 mm CW) could 



T 

 30 



50 60 70 



Cod Length (cm) 



Figure 8 



Relationship between the carapace width (mm) olHyas araneus and H. 

 coarrtatus found in the stomachs of cod. and length (cm) of the cod, all 

 cod samples combined for 1981 and 1982. 



