This bird is at 46-60 cm (18-24 in) and 120 to 153 cm (47 to 60 in)wingspan. They can weigh from 600 to 1,660 g with females typically heavier than males. The plumage is mainly brown in colour, often showing a high degree of speckling. Its feet are feathered to the toes. The species exhibits a wide variety of plumage patterns including light and dark morphs. In all plumages, this species has long white tail feathers with one or more dark subterminal bands. The wing tips are very long. A broad brown chestband is present in most plumages.
Habitat and Distribution
The Rough-legged Hawk breeds in tundra and taiga habitats of North America and Eurasia. North American birds migrate to the central United States for the winter, while Eurasian individuals migrate to southern Europe and Asia. During these winter months, from November to March, preferred habitats include marshes, prairies and agricultural regions where rodent prey is most abundant.
This species is carnivorous, voles and lemmings are the major prey items. They will also supplement the diet with mice, rats, gerbils, pikas and insects. Birds are the second most favoured type of prey.
Breeding sites are usually located in areas with plenty of unforested, open ground. Depending on snow conditions, migrants arrive at breeding grounds during April and May. Nests are built soon after arrival to breeding grounds and require 3-4 weeks to complete. Twigs, sedges and old feathers are used as building materials. Females can lay 1-7 eggs. Minimum incubation period is 31 days, the male feeds the female during this period.
Calls and Songs
They vocalise alarm calls when intruders approach a nesting site. It is described as a downward slurring whistle, sounding like kiu wiyuk or a lengthy descending kee-eer similar to that of the Red-tailed Hawk.