You may never see Sharp-shinned Hawks, but they certainly pass through your backyard. Sharp-shinned Hawks are some of the most significant predators of small birds, which make up the majority of their diet, so as you might expect, bird feeders make easy hunting grounds. Here’s a good clue to their presence, as well as that of their close relatives Cooper’s Hawks: look out at your bird feeder and there are only one or two birds, stationary and not eating. This is usually the aftermath of a Sharp-shinned Hawk flying through looking for prey. Scan the trees around the edge of the yard and you may see a Sharp-shinned Hawk perched and hidden, calculating its next flyby. These hawks rely on this element of surprise to hunt successfully; when they are spotted, they are almost always “mobbed” by prey species and driven out of the area. The Accipiter hawks, Sharp-shinned and Cooper’s, are easy to distinguish from other raptors by their long tails and slender bodies.
Telling the two apart is far more difficult, and one of the classic challenges of North American birding. Sharp-shinned Hawks are the smaller species, with proportionally smaller heads that make their eyes look huge, often described as “bug-eyed”. Proportions are more helpful than overall size, especially since both species are highly sexually dimorphic, with Sharp-shinned Hawks displaying some of the most pronounced differences between the large females (5-7 oz) and smaller males (3-4 oz). Whichever Accipiter you find, September is probably the best time to see them, as they migrate south in huge numbers along the coast and mountain ranges. Keep an eye out at your feeders for these fast, agile hawks, and remember: they need to eat too!
Backyard Bird of the Month is a feature by Maine Audubon created for the Maine Home Garden News, the newsletter of the University of Maine Cooperative Extension: Garden and Yard
