Common Names: Ferruginous rough-leg, eagle hawk, gopher hawk

Etymology: buteo (Latin) - "a kind of hawk"; regalis (Latin) - “royal,” referring to the bird’s large size

Description: Ferruginous hawks are massive broad-winged hawks with large head and robust chest. They are the largest buteo in North America. The sexes are similar, but females tend to be darker on the legs and belly. Ferruginous hawks typically exhibit either a light or dark morph. Light morph adults can be distinguished by a white/gray tail and nearly white underparts, broken only by rufous or gray specks on the belly. The dark legs and tarsi held under the rump in flight form a characteristic rufous V. From above, head is whiter than that of most hawks, with back and shoulders rufous and a white area or “window” in extended primaries. Dark morph birds are entirely brown, with grayish tail. Both morphs have yellow toes, cere, and mandible margins.

Flight: These hawks soar and circle with slightly uptilted wings. They will fly low to ground when approaching prey. They also employ dynamic soaring, alternately rising several hundred meters into the air and then falling very steeply to within a few meters of the ground to take advantage of lower wind speed near the ground.

Voice: Alarm Call, kree-a or kaah kaah, is described as similar to Herring Gull; often seems weak and plaintive.

Habitat: Their breeding range habitat consists of flat and rolling terrain in grassland or shrub-steppe regions. They avoid high elevations, forest interiors, and narrow canyons. Sparse forests, cliffs, and isolated trees in grassland areas are sought for nesting. Birds show a preference for elevated nest sites, but will nest on nearly level ground when elevated sites are absent. They commonly winter around prairie-dogs but also near cultivated fields with pocket gophers. Sometimes they roost communally in groups of 5 - 10 birds. They are often associated with Swainson’s and red-tailed hawks, which may be beneficial due to joint defense of overlapping territories increasing nesting success.

Distribution: Western North America from southern Canada between the Great Plains and Rocky Mountains to northern AZ and NM. Northern populations in WA, MT, ND, Alberta, and Saskatchewan are completely migratory.

Nesting: Males perform “sky-dancing.” Both male and female often dangle their legs and may grasp each other’s beak and interlock talons while spiraling toward the ground. Both pair members build or refurbish nest; male brings materials, whereas female spends time arranging and forming nest. The nest building is secretive; if interrupted, the pair may choose another site. Adults may repair 2 - 3 nests before laying eggs in one of them. Items in nests include paper, various bones, barbed wire, plastic, cow dung and steel cable found on ground. The nests are large for hawks of this size. Clutch size varies from 2 - 4 eggs but can range from 1 - 8 depending on prey abundance. Female and male both incubate; incubation period lasts 32 - 33 days. Male provides most food to nest, female feeds nestlings. Females brood young for 3 weeks, after which they begin to hunt again. Young typically leave the nest at 38 - 50 days; males leave as much as 10 days before females. Generally, the young remain dependent on parents for several weeks after fledging.

Food: Ferruginous hawks depend on few prey species including jackrabbits, cottontail, ground squirrels, and prairie dogs. Four types of pursuit described: 1) Still hunting, 2) Short distance strikes, on ground squirrels; alights and waits for prey to push soil close to surface; then pounces on the earthen heap and pulls out prey; 3) Aerial hunting used infrequently; 4) Hovering, at times when wind is strong.