Leach's Storm Petrel has an extensive global range. Breeding colonies are confined to the northern hemisphere, from the South Kuril Islands (Japan) round to Baja California (Mexico) including the Aleutian Islands, Alaska (USA) and Canada in the Pacific, and in the north-east North America, Iceland, northern United Kingdom and Norway in the Atlantic. Northern populations migration south into the tropics in winter, reaching the equator in the Pacific and as far south as south Brazil and South Africa in the Atlantic¹.