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:

Slender and elegant harrier, with narrow wings and four "fingers". Adult male easily recognized by very pale grey and white plumage, with diagnostic wedge-shaped, black wing-tips (outermost primary grey). Female and immature birds often difficult to tell from Montagu's Harrier and Hen Harrier. Adult female differs from Montagu's by lack of dark band on upper wing, and by diffuse, sooty inner underwing. Pale bands do not reach wingpit, and under coverts are darker. Differs from female Hen Harrier by noticeably slimmer wings (both hand and arm) and only 4 fingers (but beware moulting Hen Harriers). Immature similar to Montagu's with unstreaked, rufous underparts. Differs in pale tips of inner primaries, and dark half-collar and pale "boa".

Sound:

Some calls similar to Montagu's and Hen Harrier, but display call quite diagnostic. A thin, vibrating trill "peerrrrrrrr".

Display 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

CC

CC-sound:Thijs Fijen, Licence,Link.