ROPES: FOOD HABITS OF FIVE CRAB SPECIES 



Table 2.- 



-Occurrence and (percent frequency of occurrence) of foods eaten by five species of crabs 

 collected in Pettaquamscutt River, Rl, 1955-57. 



Green Crab 



Animal foods were found in 80% of the green crab 

 stomachs; plant foods occurred in 39% (Table 2), 

 This indicated a predominantly carnivorous food 

 habit with herbivorous tendencies. Of the animal 

 foods, moUusks were found more frequently (43%) 

 than arthropods (35%) or annelids (16%). Pelecypods 

 (31%) occurred more often than gastropods (16%). 

 Of the pelecypods, blue mussels were found most 

 often (24%); gem clams and other pelecypods were 

 infrequent food items. Other gastropods occurred 

 most often (1 1%) as unidentifiable broken shells or 

 operculi. The jaws of Nereis were found in 12% of 

 the stomachs. Of the plant foods, Spartina was 

 found in 31% of the stomachs, and algae in 18%. 

 Unidentified tissues occurred in 83% of the stom- 

 achs. Although 71% of the green crab stomachs con- 

 tained food, 17% of these were nearly empty. 



Stomach analyses of small green crabs (<20 mm 

 CW) caught on 6 September 1955 were sufficiently 

 different to warrant separate representation (Table 

 3). Animal and plant foods occurred with equal fre- 

 quency (69%) in the stomachs. Of the animal foods, 



Table 3.— Occurrence and (percent frequency of occurrence) of 

 foods eaten by small (<20 mm CW) green crabs caugtit on 6 

 September 1955. 



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