We were very pleased to get a close view of this rarity. This distinctive subspecies of the Red-tailed
Hawk breeds in Alaska, the Yukon and extreme northern British Columbia. It is a very rare but regular winter visitor
to California. The taxonomic status of this bird has been hotly debated but it is currently considered a subspecies
by most authors. In the more common dark morph, it differs from other Red-tail subspecies in the unique white bases
to the body feathers which show up as variable spots and blotches on the underparts as seen here. Note also white
streaking on its forehead. It usually lacks red in the tail and has more extensive tarsal feathering. Recently
the North American Checklist Committee unanimously rejected a controversial proposal to elevate Harlan's to species
status. See interesting commentary here.
Canon SX60 HS PowerShotReferences:
Global Raptor Information Network. 2019. Species account: Red-tailed Hawk Buteo jamaicensis. Downloaded from http://www.globalraptors.org on 25 Nov. 2019
Clark, W. S. 2018. Taxonomic status of Harlan’s Hawk Buteo jamaicensis harlani (Aves: Accipitriformes). Zootaxa 4425 (2): 223–242. https://doi.org/10.11646/zootaxa.4425.2.2
Liguori, J., and B. L. Sullivan. 2010. Comparison of Harlan's Hawks with western and eastern Red-tailed Hawks. Birding 42:30-37.
White, C.M., Boesman, P. & Marks, J.S. (2019). Red-tailed Hawk (Buteo jamaicensis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/53135 on 25 November 2019).