Great Shearwater (Ardenna gravis)
Yellow-billed Loon (Gavia adamsii)
Large shearwater with distinct, marked, dark cap and white collar. Blotched belly and underwings. White upper tail-coverts forms a horseshoe mark, but note that Cory's Shearwater may show the same. Dark patch at side of neck. Bill dark. Flight action powerful, with alternating glides and rapid bursts of beats with stiff wings. Seldom soars.
Sound:Calls at breeding ground a deep, soft, moaning "oooh-aahh" ("surprised or shocked old lady"). Tone fairly clear, and pitch rising and falling.
Distribution:Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCLarge and bulky diver with yellow or whitish, heavy bill and square head profile with steep forehead. Usually holds bill uptilted, not pointed straight like Great Northern Diver. Summer: White underparts and chequered black back. Black head and neck with white horizontal band. Winter: White underparts and grey back. Neck usually much more diffusely marked than in Great Northern Diver. Heavy goose-like flight.
Sound:Song similar to Great Northern Diver, but slower and harsher. Not very vocal.
Song:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-photo:Seabamirum, Licence,Link.
CC-photo:Bering Land Bridge National Preserve, Licence,Link.