SUBSPECIES OF THE RED-TAILED HAWK IN THE NORTHEAST
1987
The heavily streaked, richly colored population of the Red-tailed Hawk (Buteo jamaicensis) nesting in the spruce-fir belt of Canada from the Peace River Delta of Alberta east to Nova Scotia was named Buteo jamaicensis abieticola by Todd (1950). Parkes (1952) recognized the subspecies, and in his unpublished thesis "The Birds of New York State and Their Taxonomy" he listed by museum number and locality the specimens he had identified as abieticola in the collections of the American Museum of Natural History (AMNH), Cornell University (CU), and the National Museum of Natural History (USNM). However, the taxonomy of the U.S. and Canadian populations has been confused, and abieticola has not received general recognition. The most recent author to mention it, Godfrey (1986), stated that he had seen insufficient material to evaluate its validity. Peters (1931) was misled by certain heavily pigmented eastern specimens (i.e., those later to be named abieticola by Todd), believing them to be the same as the richly colored but finely streaked western populations generally called calurus. He therefore considered calurus to be a synonym of the eastern borealis. Bull (1974), who (as noted earlier; Dickerman 1986) had Parkes's thesis available during the preparation of "Birds of New York State," wrote that two distinct races occur in New York, "the large race borealis" and "the race calurus (darker and more heavily marked below than borealis, also much more variable and highly polymorphic)." Although a large series of true calurus was available to him in the AMNH, Bull misunderstood the characters of that subspecies. To dispose quickly of size, Todd (1950) specifically stated that abieticola does not differ in size from borealis, and comparison of his measurements of the former with those of borealis given by Friedmann (1950:239) bears this out. Friedman's measurements of calurus (1950:247) suggest that this race averages slightly larger than borealis, the opposite of what Bull indicated. As for color, the dark ventral markings of true calurus (except on the thighs) are little if any heavier than in borealis. Furthermore, abieticola, which is more heavily marked on the underparts, is not "highly polymorphic" and is no more variable individually than is borealis. Bull went on to say that "At least 13 specimens of calurus have been taken within the state, chiefly in late fall of various years. Most of these [were] examined by the writer
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