Petrel, an ocean bird belonging to any one of three families. There are about 50 species of petrels, widely distributed around the world. Several species nest in United States coastal areas. Petrels range in length from 6 to 38 inches (15 to 97 cm). They are sooty black or dark gray above and pale gray or white below. A few species of white petrels inhabit antarctic regions.Storm petrels often skim the water when flying.
Petrels have hooked bills and tubular nostrils. Some species have long, pointed wings, while others have short wings. The legs of some species are short and stout, but others have long, thin legs that are so weak the birds use their wings to help support them on land. Petrels have webbed feet. Most species have short tails.
Petrels stay at sea except at nesting time, when they gather in flocks on rocky coasts and islands. They dig burrows for their nests, or lay their eggs in crevices between rocks. The nests may be lined with sticks or leaves. The female lays one white egg, and takes turns with the male in incubating it. Petrels feed on algae, fish, squid, and small crustaceans such as shrimps. Some species eat smaller birds and their eggs. A number of species follow ships to feed on refuse.
Storm petrels are so named because of the belief that their presence means that a storm is coming. They are also called Mother Carey's chickens, a name of uncertain origin. These are the smallest petrels, ranging from 6 to 10 inches (15 to 25 cm) in length. Storm petrels fly close to the water when feeding, patting the surface with their feet and giving an appearance of walking on water. Among the species that nest in the United States is Wilson's storm petrel, a ship follower.
Storm petrels are very tiny birds. They are so tiny that you could hold one in your hand. A storm petrel may weigh as little as 1 ounce (30 grams). A bird so light in weight needs to be careful in strong winds. That may be why storm petrels fly close to the surface of the water.
Storm petrels do not come ashore often. When they do, it is usually to breed and to lay eggs. Storm petrels often build little nests underground. Being underground protects them from many enemies.
Diving petrels also fly close to the sea's surface, diving through the waves. They often swim underwater. These petrels are not migratory, and are generally limited to the Southern Hemisphere.
The giant petrel, snow petrel, and cahow (or Bermuda petrel) are related to the shearwaters. (See Cahow.) The giant petrel, the largest species of petrel, ranges from 32 to 38 inches (81 to 97 cm) in length. The snow petrel, an all-white species, is about 16 inches (41 cm) long. Both inhabit subantarctic regions.
Storm petrels make up the family Hydrobatidae; diving petrels, the family Pelecanoididae. The giant petrel and snow petrel belong to the shearwater family, Procellariidae. Wilson's petrel is Oceanites oceanicus; the common diving petrel, Pelecanoides urinatrix; the giant petrel, Macronectes giganteus; the snow petrel, Pagodroma nivea.