Habitat
Breeds in salt and brackish water on shores, barren islands, bays, estuaries, cliffs, rock ledges, mud flats, grassy slopes, beaches, harbors of coastal cities, and dumps (Verbeek 1993, NatureServe 2007b). Nests coastally, on cliffs, rocks, grassy slopes, mostly on offshore rocks and islands; preference for sandbar islands, flat tops of rugged islands, or beaches (NatureServe 2007b). In B.C., all major breeding colonies are on islands less than 25 ha in size and 100m in height (Campbell et al. 1990).
References
Campbell, R. W., N. K. Dawe, I. McTaggart-Cowan, J. M. Cooper, G. W. Kaiser, and M. C. E. McNall. 1990. The Birds of British Columbia. Vol. 1 and 2, Nonpasserines. UBC Press, Vancouver, B.C.
NatureServe. 2007b. NatureServe Explorer: An online encyclopedia of life [web application]. Version 6.2. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer.
Verbeek, N. A. M. 1993. Glaucous-winged Gull (Larus glaucescens). In The Birds of North America, Vol. 2, No. 59 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists’ Union.
