One of the most challenging aspects of identifying smaller Raptors (Acipiters) occurs when you encounter a “Feeder Hawk”. Sharp-Shined and Cooper’s hawks have attained the distinction of being called a “Feeder Hawk” as they prey on birds which congregate around feeders.
From afar both of these birds seem to be identical; however there are several unique features which need to be considered to make the precise identification.
As with all raptors the female is always larger than the male, as much as 30% bigger. Sharp-shined hawks range in size from 25 cm (male) to 36 cm (female) and Cooper’s hawks from 36 cm (male) to 51cm (female). So if you see a Feeder Hawk which is about 36 cm it could either be a female Sharp Shined or a male Cooper’s. Both adult species have red eyes and very similar in colour. Sharp shined hawks have a shorter squared tail, while the Cooper’s has a longer rounded tail. The Cooper’s also has a slightly larger head. Another test to use is eye placement: Sharp Shined eyes appear to be half way between front and back of head while Cooper’s eyes appear to be close to the front of the head.
In flight the Sharp-shined have short rounded wings that are pushed forward at the wrists so that the small head barely extends past the wings. Cooper’s has a large angular head which projects beyond the wings when soaring giving the bird a cross-like appearance.
Both juvenile species have yellow eyes, dark vertical stripes on their breasts, and variable brown backs and heads with some white spots.
The difficulty of distinction is seemingly more pronounced when comparing a juvenile Sharp-Shined versus a Cooper’s. Yet there are certain markers which can lead to the right call, a Sharp Shined has Heavy, bold, reddish streaks on chest and belly; whereas a Cooper’s has finer streaks mostly on upper breast and the lower belly is mostly white. A Sharp-Shined has a pale stripe above the eye and a Cooper’s often has reddish color on side of head and nape.
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