Rough-Legged Hawk

Scientific name- ” Buteo lagopus“

The Rough-Legged Hawk is a large hawk species from the “Buteo” genus. Their name comes from the fact that their legs are feathered clear down to their toes. We call them the Rough-legged Hawks in North America. However, they also go by the common name Rough-legged Buzzard in Europe and Asia. This is due to the fact that the buteos that we call hawks in North and South America are called buzzards in Europe, Africa, Asia, Indonesia, and Australia. Other North American buteos are Red-Tailed Hawks (Buteo jamaicensis), Red-shouldered Hawks (Buteo lineatus), Broad-winged Hawks (Buteo platypterus), Swainson’s Hawks (Buteo swainsoni), Zone-Tailed Hawks (Buteo albonotatus), Short-Tailed Hawks, (Buteo brachyurus), Gray Hawks, (Buteo plagiatus) and Ferruginous Hawks (Buteo regalis).

During the breeding season, Rough-legged Hawks are a bird of the arctic tundra and boreal forest regions. However, they do migrate to lower latitudes in the fall.

Rough-Legged Hawk Characteristics

Rough-Legged Hawks are 18 to 22 inches (45.7 to 55.8 cm) long with 48 to 56 inches (122 to 142 cm) wingspan. They weigh from 1 1/2 to 3 pounds (.68 to1.36 kg). Source

These are large, broad-winged hawks. However, compared to other Buteos, their wings are fairly long and narrow. The Rough-Leg’s tail is also longer than that of most other buteos. Their wingtips are proportionately broad. In-flight, they will often sweep their wingtips back slightly at the wrist. This gives the suggestion of an M shape to the wing.

The Rough-legged Hawk’s legs are feathered down to its toes. It is one of four North American raptors with feathered legs. The other three are Golden Eagles, Gyrfalcons, and Ferruginous Hawks.

Rough-Legged Hawks are variable in their plumage with two color morphs, light morph and dark morph birds. Adult birds are generally mottled reddish-brown on top with brown-streaked underparts and barred legs. Their tails are dark at the tip and pale at the base. Adult female birds have a single well-defined dark tail band. On the other hand, adult males may have as many as five tail bands. Female Rough-legged Hawks also have a well-defined dark band across their abdomens that the males of the species lack. Juvenile birds have cream-colored underwings with very little mottling. They also lack a well-defined tail band.

Rough-Legged Hawk Range

The breeding grounds of the Rough-Legged Hawk are in the tundra and northern boreal forest regions of North America, Asia, and Europe, between the latitudes of 61° and 76° N. This bird inhabits the complete circumference of the northern polar region of the earth in the summer.

The Rough-legged hawks of North America migrate as far south as southern Canada and the United States for the winter. In Europe and Aisa, these birds also migrate to the southern end of their continents for the winter. From November through March, these birds prefer open areas such as prairies and the agricultural regions where rodents are abundant and easy to find. Source

Rough-Legged Hawk Habitat

During the breeding season, Rough-legged Hawks live in the arctic regions of both North America and Eurasia. Although they sometimes use the northern end of the taiga forest, most of their nests are north of the tree line, on the tundra. They build their nests on cliffs, rock outcroppings, or occasionally in the stunted trees on the northern end of the taiga.

Their primary prey is rodents, so they require vast areas of open country to hunt in. They hunt over bogs, meadows, and clear cuts in forested areas. In late October, they migrate to their winter grounds across southern Canada and most of the United States in North America. The European and Asian versions of Rough-legged Hawks also move south for the winter. In the wintertime, these birds prefer open country with abundant rodents to prey on.

Rough Legged Hawk Prey

During the summer breeding season, Rough-legged Hawks primarily feed on small mammals, specifically rodents such as lemmings, pikas, ground squirrels, and voles. Seventy to ninety percent of their diet consists of small rodents. Like all hawks though, they are opportunistic hunters and will also prey on snowshoe hares, waterfowl, ptarmigan, and small birds when they are available.

In the winter, Rough-Legged Hawkes feed on mice, voles, squirrels, rabbits, and occasional birds. In the winter, they are also more likely to feed on carrion.

Voles leave scent trails of urine and or sebum. These trails would otherwise not be visible without ultraviolet light. Some evidence suggests that Rough-legged Hawks can see vole’s scent trails Source and use them to concentrate their search area for voles.

Rough-Legged Hawk Behavior

Hunting

Rough-Legged Hawks are both diurnal and crepuscular hunters. Diurnal connotes being active during daylight hours, while crepuscular activity occurs at dawn and dusk. Additionally, they are open country hunters. They typically hunt from the air more than other buteos and have more success doing so. They hover in place high above the ground either by rapid flapping, or simply glide on the air currents with stationary wings as they scan back and forth for prey. Although they primarily hunt from the air, they may also hunt from a perch such as a fence post, a haystack, a tree, or a utility pole over an open field. Rough-legged Hawks are also known to steal freshly killed prey from other raptors and ravens.

Mating

After spending the winter in either southern Canada or the United States, Rough-legged Hawks arrive back at their arctic breeding grounds in April and May.

In courtship, rough-leg pairs call while circling and soaring together. Sometimes they also do this individually. Male rough-legs will sometimes execute “sky dances“. These displays include sinuous flights, in which the male dives downward with his wings drawn in, only to climb back up steeply and hover briefly before repeating the sequence.

Rough-legged Hawks are monogamous for the duration of the breeding season, and occasionally, pairs are observed together on their wintering grounds.

Rough-Legged Hawks prefer to nest on cliffsides and rock outcroppings. They will also occasionally nest in trees. Sometimes they will share the same cliffside with other birds such as Gyrfalcons, Peregrine Falcons, or even Ravens, but they strive to keep at least a 1/4-mile buffer zone between themselves and other Rough-legged Hawk pairs. Source

A Rough-legged Hawk’s nest consists of a stick platform that is 10 to 24 inches high and up to 36 inches across. On the treeless tundra, the majority of the sticks will be willow. The nest bowl is lined with grass, sedges, small twigs, and molted feathers.

Their clutch size generally consists of 3 to 5 eggs, but it might be as small as 1 egg or as large as 7. Their incubation period lasts for 31 to 37 days. The female does most of the incubating while the male provides her with food.

Rough-Legged hawk Life History

After hatching, the chicks need to be brooded for an additional 4 to 6 weeks before they fledge. These fledglings will still depend on their parents for food for up to another 4 weeks.

Immature roughlegs will migrate to their wintering grounds in the fall along with the adults. They’ll reach sexual maturity at 2 years of age. It is thought that the vast majority of them do not survive past 2 years of age, but if they do make it to maturity, they can survive up to 19 years in the wild.