This mid-sized, pink-legged gull has caused much of the confusion in west coast gull classification and identification. Its plumage characteristics are similar to Herring, Iceland, and some Glaucous-winged hybrids, and great care is needed for correct identification. It differs from the Herring gull in having a much smaller bill, a darker eye, less black in the wing-tips and, often, a more rounded head.

Opportunistic feeders, Thayer's gulls regularly concentrate about landfills, food-processing plants, and over fish runs. It is a common migrant and fairly common winter visitor along the coast. The largest wintering numbers are found in the Portland metropolitan area where flocks of several hundred are not uncommon.

Hear the call of the Thayer's gull

Photo by Jerry McFarland, Flickr