Staudinger: Predation by four fish predators on two squid species on the Northwest Atlantic continental shelf 



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The proportion of squid consumed by summer flounder 

 fluctuated significantly among seasons (^n(/,„j,„/=14.29, 

 P=0.003, n = 43). Predation on squid was at its maxi- 

 mum during winter, and elevated during the summer 

 in comparison to spring and fall (Table 2). Although 

 differences in squid predation among size classes were 

 not significant <//„,/,„,„,</=2.33, P=0.312, ;! = 132), squid 

 contributed the greatest relative amount to the diet of 

 medium flounder (Table 1). The dominant species of 

 squid identified in all size classes and for all seasons 

 was longfin squid. Shortfin squid was found only in the 



diets of large flounder (Table 1) and only during the 

 winter season (Table 2). 



Discussion 



Seasonal predation on squid 



Previous descriptions of predation on squid in the North- 

 west Atlantic have been based on sampling in the fall 

 and, to a lesser extent, during the spring seasons. Survey 



