Marine Wildlife Encyclopedia
Wilson's Storm Petrel Oceanites oceanicus
Little bigger than a sparrow, Wilson’s storm petrel is reputed to be the world’s most numerous ocean-going sea bird. It breeds in widely scattered colonies, and its total population is unknown but may exceed 20 million. At sea this bird may be difficult to distinguish from its close relatives, but its plumage is uniformly sooty brown, apart from a band of white at the base of its tail. When feeding, storm petrels rarely settle on the water. Instead, they flutter their wings and patter the surface with their feet, pecking up planktonic animals. When food is abundant, they may suddenly appear in huge numbers then disappear with equal abruptness. Wilson’s storm petrel breeds as far south as Antarctica, digging a burrow with its bill and feet. It migrates northward when the southern summer comes to an end.