Observations on the seabirds of Manawagonish Island, New Brunswick: movements and population changes 1940-1983.

Abstract

Since 1940, significant changes in the population of seabirds nesting on Manawagonish Island, New Brunswick have been observed. Most notably there were large increases in the numbers of nesting great black-backed gulls, Larus marinus, and double-crested cormorants, Phalacrocorax auritus. Dispersal patterns for herring gulls, L. argenfatus, from this colony show a late summer and early fall movement northward in to the Northumberland Strait and Gulf of SI. Lawrence, as well as southward travel as far as the Gulf of Mexico and a summer concentration around Cape Cod. During the winter months birds appear to congregate in metropolitan areas between long Island and Philadelphia.