Swallows and martins are small, aerial feeders with rather slender bodies and long, pointed wings which are held angled in flight, the wrist of carpal joint being further from the body than in swifts. They are extremely maneuverable and their short, pointed bills and wide gapes are well adapted for catching their invertebrate food in the air. Swallows and martins have very short legs but are able to perch.
The only all-dark hirundine apart from the uncommon Purple Martin. ADULT: Dark blue overall, with broad, pointed wings and slightly forked tail. ADULT FEMALE / JUVENILE: Sooty-black above and dark brown below, usually appearing all-dark in flight.
A short, warbling song, a twittering flight call "cher-cher", and a high-pitched alarm call are the most frequently heard vocalizations.
Flight action consists of alternating flaps and glides. Galapagos Martins are commonly seen during a Galapagos cruise.