Other Names: Leach's Petrels, Carrie Chicks
Found on inaccessible islands in the colder northern areas of the Atlantic and Pacific, such as Baccalieu Island of eastern Canada (which houses the largest colony of these birds - more than 3 million of them). In Europe, records of them exist from Liverpool Bay, between north Wales and England; the remote Scottish islands of North Rona and Sula Sgeir.
This small seabird measures 18 - 21 cm in length and has a wingspan of 43 - 48 cm.
The plumage is all dark, except most have a white rump, although some individuals with dark rumps have been recorded on the west coast of North America. The highest percentage of dark-rump birds occur on the United States - Mexico border where 90-100% of adult birds have dark rumps. Dark-rump birds are rare north of southern California,