At least five subspecies recognized,
although the subspecific taxonomy remains complex and poorly resolved:
U. a. aalge
U. a. albionis
U. a. hyperborea
U. a. inorata
U. a. californica
Also known as Common Guillemot or
The distribution of bridled individuals
varies with latitude. As many as 50% of birds may be bridled in the extreme
north. Field separation of the different races is poorly understood as
is somewhat clinal in nature. Subspecies differ in terms of size, darkness
of plumage, prominence of flank streaking. The southern race albionis (southern
British Isles and adjacent continental europe) is lighter brown and has
weaker flank streaks than more northern races.
Where and When
Photographs on the web
Beached adult in alternate plumage Whidbey Island, Washington State. Photo by Jim Nestler.
Immature at sea San Juan Islands, Washington. Photo by Jim Nestler.
adults Photos by Gaylord Mink
Ventral view of an adult in alternate plumage. Photos by Arthur Morris and hosted by Don Crockett/The Virtual Birder.
views of two adults in alternate plumage. Photos by Arthur Morris and
hosted by Don Crockett/The Virtual Birder.
Gaston, A. J. and Jones, I. L. (1998) The Auks. Bird Families of the World 4. Oxford University Press.
Harris, M. P., D. J. Halley, & S. Wanless. (1996) Philopatry in the Common Guillemot Uria aalge. Bird Study 43: 134-137.