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:

White forehead with white wedge above eye in all plumages. Legs, and most of bill yellow in adult breeding plumage. Very small and longwinged tern. Only 2/3 of size of Common Tern. Head and bill proportionally longer than Chlidonias species and congeners, while tail is shorter. Back paler grey and belly whiter. First primaries form a dark front edge to wing. In winter the bill darkens, legs turn a dirty yellow and the white forehead expands. Juvenile resembles adult winter, but has yellowish bill base and scale patterned back. Flight fluttering with rapid wing-beats, which together with size, is usually sufficient to determine the species.

Sound:

Fairly distinct voice. Contact call a sharp "kitt", often combined to form undulating, rolling series. Not as sharp and penetrating as Common- and Arctic Tern.

Contact call:

Distribution:

Xeno-canto: map

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

CC-photo:Lars Buckx, Licence,Link.