Northern Redtails

Ron Pittaway

Published in OFO News Volume 16(1): 4. February 1998

Most of the Eastern Red-tailed Hawks (Buteo jamaicensis borealis) seen at Ontario hawkwatches can be separated into two recognizable forms: northern and southern. The southern form breeds south of the Canadian Shield and the northern form breeds north to James Bay.

W.E. Clyde Todd, of Birds of the Labrador Peninsula fame, described the northern population of the Eastern Red-tailed Hawk breeding in the boreal forest as B. j. abieticola which means "dweller of the fir". Typical adults of this proposed subspecies differ from the redtails breeding in southern Ontario by having bolder and more heavily marked belly bands, more streaked and darker throats, and buffier underparts. Juveniles often can be identified by their greatly increased blackish belly band, rarely almost forming a solid band.

Study the redtails breeding in southern Ontario. They have lightly marked belly bands (some lack them) and are very white below, including the throat. Southern adults are at their nests by March. The adult redtails migrating by the Niagara Peninsula Hawkwatch near Grimsby in April are mainly northern redtails. In October and November, most of the redtails passing High Park Raptor Watch in Toronto are also the more heavily pigmented northern birds. Many northern redtails winter in southern Ontario.

By studying the appearance of the redtails breeding in southern Ontario and comparing them with the more migratory northern birds, you will see the difference with practice.