The prevalence of plastic in 18 species of seabirds at seven study sites in the Hawaiian Islands and Johnston Atoll was studied during 1986 and 1987. Stomach samples were collected by induced emesis from 1,803 live birds of 15 species and during necropsy of 277 dead birds of 5 species. The prevalence of ingested plastic varied greatly among species; age, year of collection, and location of the study site had less pronounced but significant effects. Ingested plastic was absent or uncommon in terns and noddies. Plastic was not found at all in samples from gray-backed terns, Sterna lunata, or white terns, Gygis alba. The prevalence was low in sooty terns, Sterna fuscata (0 to 8%), and brown, Anous stolidus, and black noddies, A. minutus (0 to 3%). Plastic was much more prevalent (67 to 100%) in chicks of black-footed, Diomedea nigripes, and Laysan albatrosses, D. immutabilis. In the 11 other species prevalence ranged from 0 to 44% depending on the age, year of collection, and location. The mean volume of plastic in samples collected at necropsy from Laysan albatross chicks was higher in 1986 (46 cc) than in 1987 (5 cc). Prevalence was generally higher in seabirds which fed at the surface. Fragments of manufactured articles were the most common type of plastic found. Other plastics included pellets, Styrofoam, bottle caps, bags, and sponges. The largest individual item (200 cc) and the greatest diversity of plastic items were found in albatross chicks.
