Female remains with young at first; male brings food, female feeds it to young. Mostly rodents. On breeding grounds, feeds heavily on lemmings and voles. Also eats many birds. In winter and migration, eats voles, mice, ground squirrels, other small mammals, plus occasionally birds, frogs, insects.
May readily feed on carrion in winter. In breeding season, members of pair circle together high in air. One may perform sky dance, alternately flapping to high elevation and then diving steeply.
Nest site is usually on a narrow ledge or niche in high cliff. Sometimes nests on slopes, atop large rocks, even on level ground. At edge of forest, may nest in top of tree. Nest is a bulky structure of sticks, bones, debris, lined with grasses and twigs. Learn more about these drawings. Migrates relatively late in fall and early in spring. Numbers appearing south of Canada are quite variable from one winter to the next.
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too. A veteran counter reflects on shifts in New Jersey's birds during the past 40 Decembers, for better and for worse.
Many familiar species depend on the Arctic for breeding. Discover seven of them and test your bird smarts with this quiz. Latin: Buteo regalis. Latin: Aquila chrysaetos. Latin: Circus hudsonius. Latin: Buteo jamaicensis.
Soars and alternately flaps and glides while migrating. Hovers when hunting. The Rough-legged Hawk is a large, long-winged Buteo of open habitats. The species, named for its feathered legs, breeds throughout the arctic and sub-arctic regions of North America, Europe, and Asia. In North America, roughlegs typically breed in the open tundra and semi-open taiga of Alaska and Canada. Their breeding range can extend south into boreal regions in years when prey are abundant.
In autumn, almost all Rough-legged Hawks leave the breeding grounds and migrate to wintering grounds in southern Canada and the northern United States. Wintering roughlegs typically select open habitats similar to those on the breeding grounds. Expansive agricultural lands and airports are often used in the East.
In winter, roughlegs often concentrate in large numbers in areas where food is plentiful. Like other Buteos, Rough-legged Hawks have long, broad wings, a chunky body, and typically soar with their tails fanned. Overall, this species has a longish tail, small feet, and a small beak for its body size. In flight the dark carpal patches of light-morph birds serve as good field marks for identifying the species.
In North America, several distinctive plumages are reported. Both light and dark morph Rough-legged Hawks occur in North America, but dark morphs are found nowhere else. Adult males and females exhibit different plumages, and adults and juveniles differ in appearance as well.
Plumages are variable in the species. Adults have dark eyes, a wide black subterminal band on the white tail, and a black band on the trailing edge of their underwings. Light-morph adult males have grayish-brown backs and wings, and brown markings on their whitish underparts. These markings typically are heavier on the breast than on the belly, and there is a well-defined light U-shaped area between the breast and belly.
The tail has multiple dark incomplete bands and a wide, dark subterminal band. Light-morph adult females have more brownish backs and wings than adult males, and their bellies are more heavily marked than those of males.
Dark-morph males are usually black overall except for the undersides of their flight feathers, which are silvery with dark bars and dark tips. Their tail feathers are dark with three or four thin white bands near the base that are visible from above.
Dark-morph females are dark brown overall and like males, the undersides of their flight feathers are silvery. The tail feathers of females are all dark above and silvery below with a dark terminal band. Juveniles of both morphs have light eyes, dusky bands on the underside of the tail, and a dusky band on the trailing edge of their underwings. Light-morph juveniles are similar to light-morph adult females and dark-morph juveniles are similar to dark-morph adult females.
Rough-legged Hawks are monogamous, and pairs raise only one brood per year. Pairs do not perform extensive courtship displays. Roughlegs call while circling and soar together or individually.
Nests are typically placed at sites that offer a broad view of the surrounding area. The species also nests on the ground along eroded river banks. Roughlegs rarely nest in trees, on level ground or on man-made structures.
Nests in trees usually are placed close to the crown. Nests, which are 60 to 90cm across and 25 to 60cm deep, are constructed of sticks and are lined with feathers, hair, moss, grass, and other greenery.
Males generally select the nest site and bring most of the nest material whereas females undertake most of the nest construction. Rough-legged Hawks lay clutches of three to seven eggs. Replacement clutches are sometimes laid, particularly if the first clutch is lost before hatching. Females do most of the incubating during the more than day incubation period, although males cover the eggs for brief periods when females leave the nest.
During incubation females are fed exclusively by their mates. Males are intercepted in midair by females as they return to the nest with prey, and females consume prey at feeding sites away from the nest. After the eggs hatch, the female broods the nestlings continually for 17 to 22 days. This species, along with the Osprey , is one of the few large birds of prey to hover regularly. This is a broad-winged raptor, typical of the genus Buteo.
Compared to the Common Buzzard , it is longer-winged and more eagle-like in appearance. Its feet are feathered to the toes hence its scientific name, meaning "hare-footed" as an adaptation to its arctic home range. Its toes are short for its size. It has a wide variety of plumages, but is typically brown above and paler below, with dark belly and carpal patches. The head is typically pale.
The tail is white with a dark terminal band. An adult Rough-legged Buzzard has an average weight of 1, g, a wingspan of cm, and an average total length of 53 cm. The female is typically larger than the male. The Rough-legged Buzzard has eight different morphs that vary with sex, age, and location.
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