DIET OF NORTHWEST ATLANTIC HARP SEALS (PHOCA-GROENLANDICA) IN OFFSHORE AREAS

The offshore diet of harp seals (Phoca groenlandica) in the northwest Atlantic was determined by reconstructing the contents of prey-contain ing stomachs (399 of 724) recovered during 1980-1995. The importance o f prey species varied seasonally and geographically. Pups (<6 months o ld) usually consumed invertebrates, capelin (Mallotus villosus), and s and lance (Ammodytes dubius). Subadults (6 months to 4 years old) cons umed capelin and Arctic cod (Boreogadus saida) in the northern part of their range but sand lance and capelin on the Grand Banks. Adults con sumed invertebrates such as shrimp (Pandalus sp.) and Natantia (amphip ods) when they were collected on the northern Labrador Shelf, but ate capelin, Greenland halibut (Reinhardtius hippoglossoides), and Atlanti c cod (Gadus morhua) on the southern Labrador Shelf. On the Grand Bank s they consumed pleuronectids, sand lance, and capelin. Atlantic cod w ere rarely eaten by seals not caught by commercial trawlers. In contra st to the seals' nearshore diet, capelin were the principal prey on th e Grand Banks and Labrador Shelf. Sand lance and Greenland halibut wer e also important. The contrast between near- and off-shore diets illus trates the importance of geographical variation in the contribution of a single prey species to the diet, especially in attempts to extrapol ate consumption of specific prey.