Comment distinguer les quatre océanites réguliers dans les eaux françaises métropolitaines ?

Storm-petrels are small seabirds found in all oceans of the world. The « storm » part of their name refers to the fact they are only found on land during very strong storms. They are strictly pelagic and they avoid land except to come ashore, usually at night, to breed in burrows, caves, or crevices. Storm-petrels, like other members of the order Procellariiformes, have specially modified « tubes » atop their bills. The storm-petrel family has two subfamilies: the Oceanitinae, composed of southern hemisphere species which are characterized by long legs (like Wilson’s Storm-Petrel), and the Hydrobatinae, composed of northern hemisphere or tropical species which typically have much shorter legs and often have forked tails.
This article presents identification criteria for the four species of ‘black-and-white’ storm-petrel that are the most regular off the French coasts: European Storm-petrel (Hydrobates pelagicus), Wilson’s Storm-petrel (Oceanites oceanicus), Leach’s Storm-petrel (Oceanodroma leucorhoa) and Madeiran Storm-petrel (O. castro). We focus on vessel-based observation since, realistically, this is the optimal means of getting to grips with storm-petrels in the field and is the main source of our experience. Land-based observation rarely affords the views essential to apply the finer points of this presentation.