Yellow-billed Loons, Gavia adamsii, nest successfully near Glaucous Gull, Larus hyperboreus, nests

Three pairs of Yellow-billed (Gavia adamsii ) nested successfully near Glaucous Gull (Larus hyperboreus ) nests in both 1983 and 1984 on the Colville River delta, Alaska (7- degree 20'N, 150 degree 45'W). Yellow-billed Loon pairs that nested near Glaucous Gulls had a larger mean brood size than other pairs in 1983. Yellow-billed Loons and Glaucous Gulls may benefit mutually by nesting near alert neighbors.