This video from the USA says about itself:
15 March 2016
The rough-legged hawk is a beautiful raptor that spends the winter in open areas across much of the United States. In spring, it migrates north to breed in the tundra and taiga of Alaska and Canada. Learn to identify this species in flight by watching this video narrated by Jerry Ligouri from HawkWatch International.
This species is also known as rough-legged buzzard.