Sharp-shinned and Cooper's Hawks

Fig. 1: Who am I? (Photo: Jerry McFarland)

The Sharp-shinned Hawk (Accipiter striatus) and Cooper's Hawk (Accipiter cooperii) are two closely related birds of prey, and pose an identification challenge that some ornithologists used to consider unsolvable.

These two species belong to the genus Accipiter, which contains about 50 other species worldwide. Only one other accipiter, the Northern Goshawk, is found in the USA and Canada. Accipiters' short, rounded wings and long tails are well-adapted for maneuvers in forested habitats.

In today's post we'll discuss how to differentiate this duo while perched; many of these traits can be used for in-flight ID as well. One of the most important themes in this post is that no field mark is reliable on its own. Thus, let a majority of traits lead you to an identification. If there's no majority, it's better to be uncertain than inaccurate!