SUMMER FOODS OF ATLANTIC WALRUS, ODOBENUS-ROSMARUS ROSMARUS, IN NORTHERN FOXE BASIN, NORTHWEST-TERRITORIES

Stomach contents of Atlantic walrus, Odobenus rosmarus rosmarus, taken by Inuit hunters in northern Fore Basin in July 1987 and 1988 (n = 10 5) and September 1988 (n = 2) were examined. In July, 20 of 94 stomach s from immature and adult walrus contained >5 g of food representing 1 7 prey taxa, including bivalves, gastropods, holothurians, polychaetes , and brachiopods. The bivalve Mya truncata contributed 81.4% of the t otal gross energy in the diet, with the bivalve Hiatella arctica, holo thurians, and the polychaete Nereis sp. contributing 7.5, 3.5, and 2.8 %, respectively. The diets of male and female walrus were similar exce pt that females received a significantly (P < 0.05) greater percentage of gross energy in their diet from H. arctica than did males. Walrus less than 3 years old (n = 11) consumed mostly milk, although some ben thic invertebrates were eaten. Analysis of the contents of two stomach s collected in September suggested that walrus may feed more intensive ly in the fall. Mya truncata was again the predominant prey, contribut ing 59.9% of total gross energy, with the bivalve Serripes groenlandic us (37.9%) replacing H. arctica (0.3%) as the second most important pr ey.