Alaska red-tailed hawk
Red-tailed hawk, Swan Lake, Victoria, BC
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Buteo
Species:
B. jamaicensis
Subspecies:
B. j. alascensis
Trinomial name
Buteo jamaicensis alascensis
Grinnell, 1909

The Alaska red-tailed hawk (Buteo jamaicensis alascensis) is a subspecies of red-tailed hawk that breeds (and is probably resident) from southeastern coastal Alaska to the Queen Charlotte Islands and Vancouver Island in British Columbia.[1] Despite its northerly distribution, this is the second smallest of the red-tailed hawks. Only the Jamaican red-tailed hawk (B. j. jamaicensis) is smaller.

The largest females from this race are smaller than almost all male red tails from other races in Canada.[2][3] In wing chord males range from 334 to 362 mm (13.1 to 14.3 in), averaging 346.5 mm (13.64 in), and females range from 358 to 363 mm (14.1 to 14.3 in), averaging 360.5 mm (14.19 in). males and females average 227.6 and 226.9 mm (8.96 and 8.93 in) in tail length, 86.9 and 83.2 mm (3.42 and 3.28 in) in tarsal length and 24.4 and 26.4 mm (0.96 and 1.04 in) in culmen length.[4][2][5] This race is darker than the pale morph of the western red-tailed hawk (B. j. calurus), nearly solidly dark brown above with almost no pale mottling on the scapulars. The breast is slightly rufous with dark arrowheads rather than streaking around the belly (although not all B. j. alascensis have the arrowheads, probably through hybridization with other races), meanwhile the rest of the underside down to the "trousers" is paler and more washed out than on B. j. calurus. Immatures of this race are usually blackish brown overall with a white throat and wide tail bands, rather unlike B. j. calurus.[4][2][6]

References

  1. ↑ Tesky, Julie L. "Buteo jamaicensis". United States Department of Agriculture. Retrieved 10 June 2007.
  2. 1 2 3 Palmer, R. S. ed. (1988). Handbook of North American Birds. Volume 5 Diurnal Raptors (Part 2).
  3. ↑ Taverner, P. A. (1927). "A study of Buteo borealis, the Red-tailed Hawk, and its varieties in Canada (No. 13)". Canada. Victoria Memorial Museum.
  4. 1 2 Ferguson-Lees, J. & Christie, D. (2001). Raptors of the World. London: Christopher Helm. ISBN 978-0-7136-8026-3.
  5. ↑ Ridgway, R. & Friedmann, H. (1919). The Birds of North and Middle America: A Descriptive Catalogue of the Higher Groups, Genera, Species, and Subspecies of Birds Known to Occur in North America, from the Arctic Lands to the Isthmus of Panama, the West Indies and Other Islands of the Caribbean Sea, and the Galapagos Archipelago. Vol. 50, No. 8. Govt. Print.
  6. ↑ Preston, C. R. & Beane, R. D. (2009). "Red-tailed Hawk (Buteo jamaicensis)". The Birds of North America. doi:10.2173/bna.52.


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