Rough-legged hawk

Description

The rough-legged buzzard (Buteo lagopus),also called the rough-legged hawk,is a medium-large bird of prey.It is found in Arctic and Subarctic regions of North America and Eurasia during the breeding season and migrates south for the winter.It was traditionally also known as the rough-legged falcon in such works as John James Audubon's The Birds of America.This fairly large raptorial species is 46–60 cm (18–24 in) with wingspan ranging from 120 to 153 cm (47 to 60 in).Individuals can weigh from 600 to 1,660 g (1.32 to 3.66 lb) with females typically being larger and heavier than males.Weights appear to increase from summer to winter in adults,going from an average of 822 to 1,027 g (1.812 to 2.264 lb) in males and from 1,080 to 1,278 g (2.381 to 2.818 lb) in females.Among the members of the Buteo genus,it is sixth heaviest,the fifth longest,and the fourth longest winged.Among standard measurements in adults,the wing chord is 37.2–48.3 cm (14.6–19.0 in),the tail is 18.6–25.5 cm (7.3–10.0 in),culmen is 3.2–4.5 cm (1.3–1.8 in) and the tarsus is 5.8–7.8 cm (2.3–3.1 in).The plumage is predominantly brown in colour and often shows a high degree of speckling.A broad brown chest-band is present in most plumages and a square dark carpal patch contrasting with the white under-wing is an easily identifiable characteristic in light morph individuals.A wide variety of plumage patterns are exhibited in light vs.dark morphs,males vs.females and adults vs.juveniles.Extensive field experience is required to distinguish between certain plumage variations Compared to its more common nearctic and palearctic cousins,the common buzzard (Buteo buteo) and the red-tailed hawk (Buteo jamaicensis),it is slightly larger,though may be outweighed by the latter.