Hydrobatidae (Oceanitidae; storm petrels; class Aves, order Procellariiformes) A family of small, brown-black or grey sea-birds which have white rumps or under-parts. The bill and legs are usually black. Storm petrels have long wings, and medium to short, square or forked tails. They are pelagic and gregarious, feed on surface plankton, and breed in burrows and crevices on islands. The two species of Oceonites inhabit southern oceans, breeding on sub-Antarctic islands, but also occur north of the Equator, following ships, and O. oceanicus ( Wilson's petrel) occurs in the N. Atlantic. The 11 species of Oceanodroma occur mainly in northern oceans and rarely follow ships. There are two–eight genera in the family, with 20–2 species, found in all oceans.

storm petrels See HYDROBATIDAE; PROCELLARIIFORMES.