Seabird and marine mammal at-sea distribution in the western Bering Sea and along the eastern Kamtchatka Peninsula

Seabird and marine mammal at-sea distribution in the western Bering Sea and along the eastern Kamtchatka (Kamtsjatka) Peninsula was determined during 114 transect counts, lasting 30 min each, in September 2018. A total of 58000 seabirds were tallied, i.e. a mean value of 510 per count. The most abundant species was short-tailed shearwater: 43250 individuals representing 74% of the total. Fulmar and kittiwake represented 13% and 8% of the total. Important geographical differences were noted, concerning both the number of seabird species and their abundance. The following species were tallied mainly in the northern zone (North of 60°N): fulmar (light morphs), short-tailed shearwater, Vega (herring) gull and horned puffin. In the southern zone, including Commander (Komandorski) Islands, observed species included fulmar (dark morphs), pelagic cormorant, glaucous-winged gull, red-legged kittiwake and black guillemot. The vast majority of the 100 cetaceans and 40 pinnipeds were tallied in the southern area, mainly porpoises, killer whale and humpback whale, and Largha (spotted) seal