ferongrey's Identifications

Looking over the edge of the Cliffwalk, this bird was circling over the narrow beach in a long, repeating oval. I began taking photos only after several revolutions. When I left a few minutes later, the bird was still circling. I'm not a bird person, but the prominently forked tail sent me to swallows and swifts, and the white marks on the tail seem restricted to barn swallows.