Petrels are the seabirds, which have about 50 species. Petrels are spread widely all around the world. Many of its species live in the coastal areas of Unites States, while some of its species like white petrel live in Antarctic regions.
Petrels have dark gray color above, while its underparts are white or pale gray. Its wings vary from short to long and pointed according to the species. Also their feet vary from a short and fat to long and thin. Their legs have web in between their toes. Those species which have long and thin legs are relatively having very weak legs that they took help of their wings to support themselves on ground.
Petrel's size ranges in length from 15 to 97 cm. They have tubular nostrils and hooked bills. Several of petrel species bear a short tail.
Petrels spend most of their time above open sea. They return to land only for nesting and breeding. Petrels are colonial birds, which lives in flocks on an island or on rocky coasts. Petrel nests in burrows. A female petrel lays a white egg in burrows or in the cracks between rocks. The parent birds take turns for incubating the egg.
Petrels live on eating squid, fish and small crustaceans. They also follow the ships to eat the discarded food. Some of its species also feed on smaller birds and their eggs.
Some petrels are called as storm petrels, because their presence indicates that a storm is coming. They are also named as Mother Carey's chickens. These birds are very tiny. There length varies from 15 to 25 cm. They are also light weight, weighing around 30 grams only. They could not bear strong winds, because of which they fly close to the land.
When the storm petrels fly close to the water, they pat the water with their feet, which gives the appearance that they are walking on water. Storm petrels prefer to live in underground nests, which protect them from many enemies.
Some of the species of petrels include snow petrel, diving petrels, giant petrel and cahow (Bermuda petrel). Snow petrels are white in color and lives in sub Antarctic regions. Diving petrels are not migratory. They swim underwater and dive through the waves. They appear in Southern Hemisphere. Giant petrels are the largest among all the petrels. Their size varies in length from 81 to 97 cm.