March 2025
Bird of the Month
Ryan Crouse

Cooper’s or Sharpie?

I’ve discussed accipiters before, the genus of woodland hawks, found worldwide. While there were once about 50 species in this genus, recent studies have narrowed it down to nine. In North America, we commonly see three species, all of which are found in the Prescott area! The most common is the backyard marauder, the Cooper’s hawk. In the higher elevations, the American goshawk is an uncommon “gray ghost” of the high-country woodlands. Lastly, there’s the smaller sharp-shinned hawk. While we enjoy the Cooper’s hawk year-around, we do experience a modest influx in migratory “sharpies” during the winter months.

An enjoyable challenge arises from the subtle visual differences between Cooper’s and sharp-shinned hawks. Even experienced birders can struggle to tell them apart. With patience, practice, and attention to detail, identifying them becomes much easier over time.

Your first test: Which accipiter are we looking at here? Image: Magdalena Richter

Both species are small to medium-sized hawks, but their bodies are broader compared to similarly sized falcons. Another shared trait are their barred tails that extend well beyond their bodies when perched. In flight they have shorter, rounded wings, ideal for high-speed maneuverability in densely wooded habitats. Their long tails form a noticeable ‘T’ shape when soaring, in contrast to the shorter, tapered tail of a buteo. As adults, both hawks have slate-gray backs and heads, with salmon-colored or buffy barring on the breast. Their eyes range from orange to garnet, darkening as they age. While young birds differ visually from adults, they are similarly difficult to distinguish from one another.

Now let’s tackle how to tell these two species apart. Methods vary by birder, but here are the techniques that work best for me. I personally find it easier identifying them in flight. Cooper’s hawks have longer, narrower wings and appear more stable on the wing. They tend to fly with fewer yet stronger wingbeats, often soaring for longer periods. A key distinguishing feature is that a Cooper’s head extends noticeably beyond the leading edge of its wings, forming a “cross” shape rather than the ‘T’ shape of a sharp-shinned hawk.

Sharpies, by contrast, have a flatter head that doesn’t extend past the obvious leading-edge “wrist kink” in their shorter, broader wings. Their flight is much more frenetic, often darting around with their short glides interrupted by flurries of rapid wingbeats. It’s almost as if they’re trying to avoid falling from the sky and are constantly correcting position.

Each species’ tail offers additional clues, although these can be unreliable if the tail isn’t spread. Cooper’s hawks typically have a rounded terminal edge, whereas sharp-shinned hawks’ tails are blockier, with crisp corners. While rounded tails may give a false-positive towards Cooper’s, a blocky tail is a clear sign of a sharp-shinned hawk.

Identifying them when perched can be trickier, but there are still useful features to look for. Cooper’s generally have a smaller head in proportion to their bodies, which extends off of their shoulders. Sharpies, on the other hand, have larger, blocky heads which give a “no-neck” appearance. This difference is one of the most useful for me when examining perched birds closely. Relative eye size is another clue: sharp-shin’s eyes appear larger compared to their heads, giving them a wide-eyed, alert expression.

Size differences also provide useful clues. While there’s significant size variation between the sexes within each species, sharp-shinned hawks are generally smaller than Cooper’s hawks. This distinction can be muddied when comparing a female sharp-shinned hawk to a male Cooper’s, as their sizes can overlap. However, if you perceive the bird to be either much larger or smaller than average, it can be a helpful indicator.

In addition to size, the overall body shape can provide some guidance. Cooper’s tend to look a bit more elongated, with narrower bodies. Sharp-shinned hawks, by contrast, have a broader, more barrel-chested appearance. One exception to this perception is that sharp-shinned hawks have longer, thinner legs than Cooper’s, which aligns with their name.

While tail shape is harder to distinguish when perched, it should be studied when possible. Again, a noticeably squared-off tail hints strongly toward sharpie. Another useful feature to look for is a white terminal band. Cooper’s hawks typically have this distinct white band at the tip of the tail, where sharp-shinned hawks typically do not.

Distinguishing Cooper’s and sharp-shinned hawks can be challenging, but with time and patience the differences become clearer. I encourage you to read up on other differences birders use and do what works for you. Ultimately the more you observe and familiarize yourself with the characteristics of each hawk, the easier it will be to spot the differences in the field. There will undoubtedly be moments when you’re uncertain, but those “Eureka!” moments of identification will make the effort worthwhile. During the uncertain times, you can be confused with the rest of us!

The Prescott Audubon Society is an official chapter of the National Audubon Society. Check it out online at PrescottAudubon.org.