Sunday, December 1, 2019

Red-tailed Hawk

Red-tailed Hawks are extremely variable across their wide, North American range. Sixteen races are currently recognized by ornithologists. Races are identified by ventral colors, tail markings, and size, but geographical trends in these characters is generally lacking. Further complicating things, adjacent races often show intermediate patterns (Preston and Beane 2009). On top of this variation, many populations are polymorphic—they come in dark, white, and intermediate colors.

Erika and I found this dark Red-tailed Hawk on 4 November 2019 at the Nisqually National Wildlife Refuge. This bird appears to be, Buteo jamaicensis calurus, the only race with a barred, not streaked, belly band. This race is the expected breeding race is western Washington, breedibg west of the Rocky Mountains from eastern Alaska soth to Arizona and New Mexico. They are resident in mucb of their range but but some winter though the southern Great Plaains to the western shores of the Gulf of Mexico south into Central America.

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