eWestern BirdsThe Quarterly Journal of Western Field Ornithologists
Vol. 40, No. 3
Western Field Ornithologists
Changes in the Winter Distribution of the Rough-legged Hawk in North America
Edward R. Pandolfino and Kimberly Suedkamp Wells
ABSTRACT: We used Christmas Bird Count (CBC) data to demonstrate a shift in the winter distribution of the Rough-legged Hawk (Buteo lagopus) in North America from the late 1970s to the early 2000s. Data from nearly 300 CBC circles reveal decreases in the Rough-legged Hawk’s abundance on the east and west coasts and throughout the southern portion of this species’ winter range. Its abundance increased in the northern portions of the Great Plains. This distributional shift was associated with a decrease in the number of December days with substantial snow cover in the northern Great Plains and an increase in the winter abundance of the Red-tailed Hawk (Buteo jamaicensis) throughout most of the range of the Rough-legged Hawk. In addition, increasing human populations and associated loss of open country may have contributed to this shift.