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Raptor Species
Rough-legged Hawk
Buteo lagopus
Taxonomy:
Class: Aves
Order: Falconiformes
Family: Accipitridae
Subfamily: Buteoninae
Genus: Buteo
Length: 18-24 in.
Weight: 1.5-3.2 lbs.
Wingspan: 3.8-4.5 ft.
Common Names: Roughleg, Rough-legged buzzard, Mouse hawk
Etymology: buteo (Latin) - "a kind of hawk"; lagopus (Latin) - "hare-footed"
Description: Rough-legged hawks are similar in size to red-tailed hawks. Their legs are
feathered giving them the appearance of “rough” legs. Individuals vary in color from very dark to light, but
all have a very dark band across their chest. In flight, conspicuous black patches show on the underside of
their wrists. They also show a wide white band at the base of the tail. Their small feet and small beaks are
adaptations to living in arctic climates. The male, female, and juvenile birds all have slightly different
plumage that differs between light and dark morph as well.
Flight: Rough-legged hawks often will hunt from the air by soaring, but will also use an
alternating flapping - gliding flight. They do less of the flap-and-glide flights as other buteos, and instead
have fairly steady wing beats. They soar with wings in a dihedral, and wings and tail fully spread, but they
do not seem as reliant on thermals as other buteos. They have been known to kite into the wind when hunting.
These hawks will attack live prey on the ground by diving straight down from above or from a slight diagonal.
Voice: Alarm call is similar to the RTHA, a descending “kee-eer” as
though high pressure steam is escaping. Both pairs have been heard to give whistling noises during courtship, and the female will often
produce a clucking sound. Not very vocal when not in breeding season except for alarm call.
Habitat: Frequently found in open, treeless areas, such as tundra. Can also be found hunting in
agricultural fields, grasslands, large river deltas, shrub-steppes, marshlands and bogs.
Distribution: Breeding range extends through the arctic tundra from Alaska through Canada. Found in
northern Europe and Asia as well. They are complete migrants, and will be seen in open areas in the northern US and southern
Canada in winter. In winter, will often be found in concentrated numbers near a good hunting area. The dark morph is more common
in eastern North America; it is rare in the west and not found in Eurasia at all.
Nesting: Will build stick nests in the tops of trees and on cliff ledges. Nesting in the highest
possible site gives a good view of the surrounding area. Will often try to return to the same nest and build on top,
but in the arctic there is a lot of competition for good nesting sites with peregrines, gyrfalcons and ravens. Ground
nests are vulnerable to predation (snowy owls, foxes, bears, wolves). They are fierce defenders of the nest, and are
monogamous at least through breeding season. Males will sometimes perform “sky dance” courtship displays, diving down
repeatedly. Lays 2-7 eggs, depending on availability of prey. In very lean years, they may not breed at all. Eggs are
white with blotches of reds, browns, and dark purples. Incubation lasts 28-31 days, with the majority of incubation
done by the female. Young fledge at 39-43 days and will disperse around 4 weeks after fledging.
Food: They will often hover-hunt, but will perch hunt also, mainly in winter. Their main source of food
is small rodents, such as mice, and lemmings. 70-90% of their diet consists of small mammals. Bird species (ptarmigan,
waterfowl, shorebirds, and songbirds) supplement their diet in the summer. They have also been known to take some larger
mammals such as Arctic ground squirrels and rabbits. Rough legged hawks have been known to steal prey from other birds such
as other rough-legged hawks, red-tailed hawks, northern harriers, American kestrels, and ravens. Are opportunists and will
feed off carrion as well. They are considered to be both diurnal and crepuscular hunters.
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