Guide to Boreal Birds
Overview
This bird has variously been considered a species of its own, a subspecies of the Herring Gull, a subspecies of the Iceland Gull, and even a hybrid of the two. At the moment, it is treated as a species. Distinguishing young Thayer's Gulls from young Herrings is very difficult.
Description
24" (61 cm). In all plumages, very similar to the Herring Gull, gray above, white below, but eye of adult dark instead of yellow. Adults have less white on underside of wing tips than do Herring Gulls.
Voice
Mewing and squealing notes.
Nesting
3 bluish or greenish eggs, spotted with brown, in a nest lined with grass, moss, or lichens placed on a high rocky cliff.
Habitat
Arctic coasts and islands, usually on rocky cliffs.
Range/Migration
Breeds in Canadian high Arctic. Winters chiefly on Pacific Coast south to Baja California. Very rare winter visitor to Maritime Canada and northeastern United States.