The Cooper’s Hawk, classified as an accipiter, may be hard to identify with certainty because two other accipiters, the smaller Sharp-shinned Hawk, and the larger Northern Goshawk have almost identical plumage. The range of all three is similar: sub-arctic Canada and Alaska to northern Mexico. Cooper’s Hawks have relatively large heads; the other two hawks have relatively smaller heads compared to body size. Male and female plumage is similar for all three accipiters, but females are larger.
All three accipiters have long tails and relatively short wings. They are very fast, and the short wings allow them to maneuver through dense forest. Click on the highlighted names above to see photos of all three accipiters from the AvianWeb. I took the photo in this post of a juvenile Cooper’s Hawk (I think) that was lunching on a dove in one of my mesquite trees. He/she will have a reddish breast upon reaching maturity.
Cooper’s Hawks have an average body length of 16.5 inches and a wind span of 31 inches. The Sharp-shinned Hawk has a body length of 13 inches and a wing span of 23 inches. The Northern Goshawk has a body length of 21 inches and a wing span of 43 inches.
The Sibley Guide to Birds notes some differences between the three accipiters:
Northern Goshawk is the largest and bulkiest accipiter. Adults appear whitish below with boldly patterned head. Juveniles are washed buffy overall with thick, spotty streaks below. There is an obvious pale bar on the forward upper part of the wings.
Cooper’s and Sharp-shinned Hawks are nearly identical in all plumages. Cooper’s is the lankiest accipiter, with large head, long neck and tail, and relatively narrow, straight-edged wings. Sharp-shinned is small-headed with relatively long, broad wings that are hunched, pushed forward and slightly more fingered at the tip. The Cooper’s tail tip is more rounded, while the Sharp-shinned is more square-tipped.
Accipiter habitat is desert, woodlands, deciduous forests, and riparian areas. They feed mostly on birds and some small mammals. They hunt from cover relying of speed and surprise.
Cooper’s Hawks nest in trees and produce three to five cobalt blue eggs. Chicks hatch after 30 to 36 days and fledge about 30 days later.
Cooper’s Hawks communicate using vocalizations and displays. Listen to some of the vocalizations recorded by the Cornell Lab of Ornithology here (Scroll down and click “sound” tab). Some of the calls sound very much like Cactus Wrens to me.
Cooper’s hawks like my yard because I put out quail blocks. I am feeding birds in two ways.