Acadia National Park

Description  ADULT SUMMER Has pale blue-gray back and upper wings, except for white trailing edge and dark wingtips with white "windows". Plumage is otherwise white. Bill is yellow with orange spot on gonys, and eye has yellow iris and orange eyering. ADULT WINTER Similar, but head and neck are streaked brown; leg, bill, and eyering colors are duller. JUVENILE AND 1ST-WINTER Have mottled brown plumage, dark tail, and dull pink legs. Initially bill is dark, but becomes dark-tipped pink by first winter. Note pale inner primaries create pale panel on upper wing and otherwise uniformly brown upper wings. Adult plumage acquired through successive molts: becomes more uniform gray on back and upper wings and whiter elsewhere. Retains dark band on tail and some brown feathering on upper wings into third winter.

Dimensions  Length: 23-26" (58-66 cm)

Habitat  Widespread and common, nesting on islands in northern lakes, and on coasts. Winter range is mainly coastal.

Observation Tips  Easy to find on coasts outside breeding season. Become familiar with proportions of known adult Herring Gulls then apply what you have learned, especially about bill size or other species shape, and colour, and wing length, to any immatures you happen to come across.

Range  Mid-Atlantic, Southwest, Southeast, Northwest, Plains, Great Lakes, Alaska, Texas, Western Canada, Eastern Canada, California, New England, Florida, Rocky Mountains

Voice  Utters distinctive kyaoo and anxious ga-ka-ka.

Discussion  Large, robust gull with relatively deep body, large head, and thick bill. Wings are long and proportionately broad and all birds have pink legs. Adult is easily distinguished from similar sized Lesser Black-backeds by its paler back and pink (not yellow) legs. Immatures are best separated by studying proportions overall and subtle differences in plumage (pale upper tail, head, and neck in Lesser Black-backed). Takes 3 years to reach adult plumage. Represented mainly by ssp. smithsonianus (aka American Herring Gull, considered a separate species by some). Sexes are similar.