Beluga Whale Distribution and Survey Effort in the Gulf of Alaska
This paper is a synthesis of available information showing the number and geographical coverage of surveys in which belugas would have been reported if encountered. Information presented includes effort and sighting data from marine mammal research projects in the Gulf of Alaska.
Beluga whale (Delphinapterus leucas) distribution in the Gulf of Alaska and adjacent inside waters was examined through a review of surveys conducted as far back as 1936. Although beluga sightings have occurred on almost every marine mammal survey in northern Cook Inlet (over 20 surveys reported here), beluga sightings have been rare outside the inlet in the Gulf of Alaska. More than 150,000 km of dedicated survey effort in the Gulf of Alaska resulted in sightings of over 23,000 individual cetaceans, of which only four beluga sightings (five individuals) occurred. In addition, nearly 100,000 individual cetaceans were reported in the Platforms of Opportunity database; yet, of these, only five sightings (39 individuals) were belugas. Furthermore, approximately 19 beluga sightings (more than 260 individuals), possibly including resightings, have been reported without information on effort or other cetacean sightings. Of the 28 sightings of belugas outside of Cook Inlet, nine were near Kodiak Island, 10 were in or near Prince William Sound, eight were in Yakutat Bay, and one anomalous sighting was well south of the Gulf. These sightings support archaeological and commercial harvest evidence indicating the only persistent group of belugas in the Gulf of Alaska occurs in Cook Inlet.
Kristin L. Laidre, Kim E. W. Shelden, David J. Rugh, and Barbara A. Mahoney. Published in Marine Fisheries Review 62(3) 2000.