Appearance:

All black swift with small white throat patch. Very difficult to separate from Pallid swift and Plain Swift. Pallid Swift; brownish plumage tone (best seen against darker background), bigger throat-patch than swift, scale pattern on body more prominent, wing-tips slightly rounded, "saddle" darker than wings, and more contrast between darker outer primaries and inner. Plain Swift; throat patch smaller and more diffuse than swift, wings and body more slender, tail noticeably deeper forked.

Sound:

A shrilling trill "zreeeee" of about 1 -2 seconds length, gradually rising in pitch with accentuated firs half, then falling from the middle of phrase. Often continued with a dry lower pitched "trrrrrr" before calling again. Very vocal at breeding area, and often a flock will call together. Despite being quite similar to Pallid Swift, the call is probably the best field character to separate the two. Pallid puts the stress on the ending of the call, followed by a quick fall in pitch (dynamics like moaning with a quick release). Plain Swift calls similar to Common Swift, but differs in slightly fluctuating pitch during the call, and a loss of resonance towards the ending (thinner sounding).

Song/contact call:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase

CC

Appearance:

Large 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

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

CC

CC-photo:Seabamirum, Licence,Link.

CC-photo:Bering Land Bridge National Preserve, Licence,Link.

CC-sound:Andrew Spencer, Licence,Link.

CC-photo:jerryoldenettel, Licence,Link.