Any of numerous seabirds (order Procellariiformes, particularly family Procellariidae), including 24 species (genera Pterodroma and Bulweria ) called gadfly petrels because of their fluttering flight.
Most are dark above and light below, with long wings and a short, wedge-shaped tail. They nest in colonies on tropical and subtropical islands. Both parents tend the single chick until it is almost fully fledged. During the nonbreeding season, petrels roam the open ocean, eating squid and small fishes. Species in the family Pelecanoididae are called diving petrels. See also fulmar , shearwater , storm petrel .