識別
A small brownish member of the swallow family. Note the slightly forked tail with white spots. Varies throughout range, from whitish gray in the northern Persian Gulf to dark brown with rust-brown underparts in central and eastern Africa; most populations are intermediate, brown above and pale below. In areas of overlap, averages smaller and paler than the very similar Eurasian Crag-Martin, with underwing coverts that are only slightly darker than the rest of the wing. At a distance, can be confused with “Riparia” martins; look for present species’ bright white tail patches. Nests in canyons, escarpments, and gorges, as well as towns and villages; often in arid areas. Often seen in pairs or small groups; in winter congregates in larger flocks. Not very noisy; sometimes gives a short, dry trill.