Delichon urbicum
A small, compact martin with short, forked tail and pure white rump. Underparts shiny white (including throat and vent). Upperparts dark with shiny metallic glow to head and back. Juveniles overall more dull, with white tips to tertials and dusky, brownish upperparts. Flight determined and steady. Glides more than Sand Martin, with less frequent change of direction.
Contact call a rolling "krreet". Similar to Sand Martin but noticeably dryer, more rolling and less raucous. Typically varies the pitch of the call more. Song a merry improvisation of chirping, contact call-like sounds (sometimes recalling a budgerigar). Warning call a sharp and plaintive "tsreee".
Wikipedia: map (se also Xeno-canto below)
Birdlife ecology
