Predation on seabirds by red foxes at Shaiak Island, Alaska.

Abstract

Two red foxes Vulpes fulva that invaded Shaiak Island before the 1976 nesting season had a marked impact on the nesting success of 5 of 7 species of seabirds breeding on the island that year. Common eiders Somateria mollissima, glaucous-winged gulls Larus glaucescens and common murres Uria aalge that nest in areas accessible to foxes, did not raise any young to fledging. Double-crested cormorants Phalacrocorax auritus were only slightly more successful; 13 (4.3%) of 300 pairs raised one or more young to fledging. Evidence suggested that 21 (35.6%) of 62 pairs of tufted puffins Lunda cirrhata lost eggs or chicks to foxes. Conversely, black-legged kittiwakes Rissa tridactyla and pelagic cormorants Phalacrocorax pelagicus, which nested primarily on cliffs inaccessible to foxes, lost very few nests. -from Author