The Washington Gap Analysis Project created breeding bird maps only. The non-breeding birds (e.g., wintering, pelagic (coastal), and birds expanding their ranges) are represented only by NatureMapping sightings.
NatureMapping observations reported by townships throughout the year.
Breeds in large colonies east of Rockies in northern tier of US states and north to edge of arctic Canada. Fairly common spring and fall migrant in Washington on outer coast. Smaller numbers on pelagic waters.Text edited by Gussie Litwer