The Red-tailed Hawk is a bird of prey, one of three species colloquially known in the United States as the "chickenhawk," though it rarely preys on standard sized chickens (All About Birds). It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West Indies, and is one of the most common buteos in North America. Red-tailed Hawks can acclimate to all the biomes within its range. There are fourteen recognized subspecies, which vary in appearance and range. It is one of the largest members of the genus Buteo in North America, typically weighing from 690 to 1600 grams (1.5 to 3.5 pounds) and measuring 45–65 cm (18 to 26 in) in length, with a wingspan from 110 to 145 cm (43 to 57 in). The Red-tailed Hawk displays sexual dimorphism in size, with females averaging about 25% heavier than males (Preston and Beane 1993).