Ferrugineous rough-leg
The Ferruginous hawk (Buteo regalis) is a large bird of prey and belongs to the broad-winged buteo hawks. An old colloquial name of this majestic bird is Ferrugineous rough-leg, due to its similarity to the closely related Rough-legged hawk. The Ferruginous hawk is endemic to the interior parts of North America and is used as a falconry bird in its native ranges also high above the land.
Adult Ferruginous hawks have long broad wings and a broad gray, rusty, or white tail. The legs are feathered to the talons. The back and wings are a brownish rust color. The head is white with a dark streak extending behind the eye. The wingtips almost reach the tip of the tail. The underside is primarily light colored with the dark legs forming a "V" shape. The reddish upper-back color extends to the inner wing-coverts or "shoulders." The primary remiges (pinions) are dark gray with conspicuous light "windows" in the inner primaries. Three prominent light areas on the upper surface stand out as two "windows" on the outer wings and a rufous rump mark, perhaps the most significant feature of a flying ferruginous hawk. The underwings are whitish overall with rufous markings, particularly in the patagial area. This gives a smudgy appearance to the wings. There are two color forms: light morph birds are rusty brown on the upper parts and pale on the head, neck, and underparts with rust on the legs and some rust marking on the underwing. The upper wings are grey. The "ferruginous" name refers to the rusty color of the light-morph birds. Dark-morph birds are dark brown on both upperparts and underparts with light areas on the upper and lower wings. As with all birds of prey, the female Ferruginous hawk is larger than the male.
The Ferruginous hawk occurs in the western and central parts of North America. Its range stretches from southern Canada to the southern USA and northern Mexico. Its preferred habitat includes arid and semiarid grassland regions, steppe, prairies, lowlands, plateaus, plains, valleys, agricultural land rolling hills of grassland, ranches, and desert edges. Nesting occurs in open areas or in trees including cottonwoods, willows, and swamp oaks along waterways. These hawks avoid high elevations, forest interiors, narrow canyons, and cliff areas.
Ferruginous hawks are territorial and favor a solitary lifestyle, pairing up only during the breeding season. Each day they hunt and patrol their territory. The flight of these birds is active, with slow wing beats much like that of a small eagle. They soar with the wings held in a strong dihedral, as well as glide with the wings held flat, or in a modified dihedral. Hovering and low cruising over the ground are also used as hunting techniques. These birds search for prey while flying over open country or from a perch. They may also wait in ambush outside the prey's burrow. Hunting may occur at any time of the day depending upon the activity patterns of the major prey species. Ferruginous hawks make a 'kaah-kaah' call when communicating with other hawks. They often rest on the ground but are wary of humans and are secretive.
Ferruginous hawks are carnivorous, eating ground squirrels, mice jackrabbits, birds, amphibians, and reptiles. Sometimes they will eat meadowlarks, snakes, lizards, grasshoppers, and crickets.
Ferruginous hawks are monogamous, keeping the same mate for their entire life. Males and females are seen together only during the breeding season, between March and June. During courtship both sexes engage in high, circling flight. The "flutter-glide" flight consists of a series of shallow, rapid wing beats interspersed with brief glides and may serve to advertise the territory. The "sky-dance" is stimulated by an intruder and consists of slow flight with deep, labored wing beats with irregular yawing and pitching that may terminate in steep dives. In the "follow-soar" maneuver, the male will fly below an intruder and escort it out of the territory. Pairs maintain minimum distances from other nesting raptors but will nest closer when necessary. Having chosen a suitable place for their nest, males bring in the building material, while females do most of the construction. These birds nest in trees, ledges, rock or dirt outcrops, on the ground, haystacks, nest platforms, power poles, and other man-made structures. They line their large stick nests with shredded bark, grass, or dried cow dung. The female lays up to 4 eggs within two days between laying. The parents work in shifts, spending equal amounts of time incubating the eggs. After up to 35 days, the eggs hatch, and the nestlings depend for the next 40-50 days on their parent until they are fully developed. They are able to breed at 2 years of age.
Their major threat is human occupation, as this leads to the loss of nesting sites. Their main breeding habitat is constantly disturbed by farmers, who will occasionally take their chickens. This disrupts breeding patterns and the size of the clutches. When several pairs are nesting close to each other, this causes constant conflict.
The IUCN Red List and other sources don’t provide the number of the Ferruginous hawk total population size. Currently, this species is classified as Least Concern (LC) on the IUCN Red List, and its numbers today are increasing.
