The Galapagos hawk is similar in size to the red tailed hawk (Buteo jamaicensis) and the Swainson's hawk (Buteo swainsoni) of North America, but the size is variable across the islands as is recorded for many animals native to the Galapagos. They appear to be somewhat more heavily built than those well known mainland species, and going on average weights, this species is the second heaviest Buteo in the Americas, behind only the ferruginous hawk. The Galapagos hawk can range from 45 to 58 cm (18 to 23 in) in length from beak to tail with a wingspan of 116 to 140 cm (46 to 55 in).[2] The smallest hawk sizes recorded are on Marchena Island, where males average 844 g (1.861 lb) and females average 1,223 g (2.696 lb).