The occurrence and characteristics of plastic pollution in Alaska's marine birds

Abstract

Major aspects of the occurrence and variation of plastic particles in the stomachs of marine birds in Alaska were examined. A total of 448 of 1 ,968 individuals and 15 of 37 species of marine birds contained plastic. Species feeding primarily by pursuit-diving and surface-seizing had the highest incidence of plastic. Crustaceanand cephalopod-feeders had a higher incidence of plastic than did fish-feeders. Birds from the Aleutian Islands averaged more particles than did birds elsewhere in Alaska. No sexual differences in plastic ingestion were found, but subadults averaged more plastic than did adults. There was a general increase in plastic ingestion between 1969 and 1977. An annual cycle of plastic ingestion was recorded, with the greatest ingestion in mid-summer. No overt effects of plastic on the physical well-being of the birds were found, but non-breeding in the Parakeet Auklet may have been caused by high plastic ingestion.