Short-billed Gull

The Short-billed Gull, Larus brachyrhynchus, is a medium-sized gull species native to the northwestern reaches of North America. It is a member of the Laridae family, distinguished by its relatively diminutive stature, with a body length of 40–45 cm (16–18 in) and a wingspan stretching between 100–120 cm (39–47 in). This species is characterized by its shorter bill and elongated wings, which give it a distinctive appearance in flight.

Identification Tips

Adult Short-billed Gulls in breeding plumage boast a pristine white head, pale eyes encircled by red orbital skin, and a yellow bill devoid of markings. Their legs mirror the yellow of the bill. Come winter, their heads are adorned with brown mottling, the orbital skin shifts to a greyish hue, and the bill dulls, revealing a faint dark marking. In flight, the white spots or "mirrors" on the two outermost primary feathers are quite conspicuous. A 'string of pearls'—white "tongue tips" between primaries 5 and 8—leads to a broad white trailing edge, with p4 often displaying black markings. Short-billed Gulls take three years to reach breeding plumage. Juveniles present a brownish hue with dark wingtips and appear darker on the head and neck compared to the paler common gull. Some first-year birds retain their juvenile plumage through winter, while others may develop greyish saddle feathers. By the first winter, the bill transitions to pink at the base with a black tip. Second-year birds resemble adults but may retain brown wing covert feathers and lack the white spots on wingtips, except for the p10 mirror. Third-year birds are closer in appearance to adults but may exhibit dark markings on primary coverts, secondaries, underwing, and tail.

Habitat

These gulls breed in colonies found along coastal areas and inland wetlands, favoring the wild expanses of Alaska and Northwest Canada.

Distribution

After the breeding season, Short-billed Gulls migrate to winter along the Pacific coast, reaching as far south as the Sacramento Valley. They are less commonly seen down to Baja California, the Northern Rockies, and Ontario. While a rare visitor to eastern North America, they are considered vagrants to East Asia and have been recorded in Europe, specifically on the Azores in 2003.

Similar Species

The Short-billed Gull is often compared to the common gull, from which it was recently split as a distinct species. It is smaller than the common gull, with a larger bill and shorter wings. The common gull also has more extensive black on the wingtips and smaller mirrors on p9-10.