- 9.4–13.4 in
- 16.9–22 in
- 3.1–7.7 oz
- On average, males are the size of an American Kestrel, slightly larger than a jay. Females are one-third larger than males, approaching the size of a male Cooper’s Hawk.
- Épervier brun (French)
- Gavilán pajarero (Spanish)
- Sharp-shinned Hawk numbers declined during the DDT pesticide years (mid-1940s to 1972), but rebounded after DDT was banned.
- Sharp-shinned Hawks migrate south out of Canada in the fall and are observed at hawk watches in very large numbers. The hawks follow similar landscape features and often are concentrated in certain areas. More than 11,000 Sharp-shinned Hawks were seen on one October day at Cape May Point, New Jersey.
- Female Sharp-shinned Hawks are about a third bigger and heavier than males. This is a typical pattern for many hawks and owls, but otherwise rare in the bird world.
- The size difference between the sexes in Sharp-shinned Hawks influences the size of prey they can catch. Nestlings feed first on small prey caught mainly by their father, switching as they grow to the larger prey that their mother can bring. Before delivering prey to their mates or young, male Sharp-shinned Hawks typically remove and eat the head.
- Adult Sharp-shinned Hawks continue to feed their offspring for several weeks after the youngsters have fledged. At first, they drop dead prey into the nest for the young to consume, but, as the fledglings gain skill, the parents switch to passing prey to the young hawks in flight. The parent approaches and calls, and the fledgling rises to grab prey out of its parent’s claws.
- Rather like a cat’s claws, Sharp-shinned Hawks use their long toes and talons to impale and hold moving prey. They’ve even been known to reach into wire-mesh bird traps to grab prey with their toes.
- Sharp-shinned Hawks carry their prey to a stump or low branch to pluck it before eating. Swallowing feathers is not normal for them, as it is for owls.
Sharp-shinned Hawks are birds of the forest and forest edge, and are not found where trees are scarce or scattered, except on migration. They require dense forest, ideally with a closed canopy, for breeding. While favoring forests that contain conifers, they also nest in stands of aspen in Colorado, oak-hickory forest in Missouri, and the hardwood forests of the East. They occupy a wide range of elevations, from sea level to near treeline. In the winter season, look for Sharp-shinned Hawks at forest edges, in somewhat more open habitats than the dense forests they breed in, as well as in suburban areas with bird feeders.
Songbirds make up about 90 percent of the Sharp-shinned Hawk’s diet. Birds the size of American Robins or smaller (especially warblers, sparrows, and thrushes) are the most frequent prey; bigger birds are at less risk, though they’re not completely safe. Studies report quail, shorebirds, doves, swifts, woodpeckers, and even falcons as prey. Sharp-shins also eat small rodents, such as mice and voles, and an occasional moth or grasshopper. While nesting, much of the food for their babies is the nestlings and fledglings of other birds.
- Clutch Size
- 3–8 eggs
- Number of Broods
- 1 broods
- Egg Length
- 1.3–1.7 in
- Egg Width
- 1.1–1.3 in
- Incubation Period
- 30–35 days
- Nestling Period
- 21–28 days
- Egg Description
- Dull-white or pale-blue splotched with brown, violet, red, or hazel.
- Condition at Hatching
- Eyes open; body covered in white down.
The nest is a broad, flat mass of dead twigs, usually conifer twigs, sometimes lined with flakes of bark. Both members of the pair bring nesting material to the site, but the female does most or all of the construction. The shallow, platform-like nest is usually 1–2 feet in diameter and 4–6 inches deep. The eggs and young often sit more on than in this wide, open-topped nest.
Throughout their range, Sharp-shinned Hawks favor conifer trees (pine, spruce, or fir) as nesting sites, but may also use aspens and hardwood trees. The nest is always placed under dense forest cover, usually toward the top of a tall tree, but well under the canopy. Most nests are anchored between horizontal limbs and the tree trunk.
Sharp-shinned Hawks are “pursuit hunters”, often surprising their prey on the wing by bursting out from a hidden perch with a rush of speed. They are versatile: small birds may be taken in the air or on the ground; they may pounce from perches as little as 3 feet above the ground to catch rodents; and they catch some insects on the wing. Sharp-shins make great use of cover and stealth to get close to their prey, surprising it at close range rather than diving from great heights. They are agile and acrobatic fliers, navigating dense woods at high speeds by using their long tail as a rudder. In open areas they sometimes fly very low, hugging ground contours to remain hidden to prey until the last moment. During their breeding season, Sharp-shinned Hawks are quiet, elusive, and nest in solitary pairs under deep forest cover; this may be to avoid their own predation at the claws of the similar but much larger Northern Goshawk. Sharp-shins get a bit more gregarious at migration, sometimes traveling in small groups at that time; they are typically the most numerous birds seen at hawk watches. This species and other accipiters fly with a characteristic “flap-flap-glide” pattern: typically 3 to 6 shallow wingbeats followed by a short glide. They also take advantage of thermals and updrafts to save energy by soaring, but rarely flap steadily except when in hot pursuit of prey. Adults feed their young for several weeks after the young can fly, as the fledglings gain hunting skills.
Sharp-shinned Hawks breed only in dense stands of trees, and so their fate is intertwined with that of wooded wilderness. Sharp-shinned Hawks are so solitary and elusive in their deep-forest breeding sites that scientists have little data on their nesting success. However, from yearly migration counts, populations are now stable or even increasing. Like other birds of prey, Sharp-shinned Hawks suffered breeding failure when the pesticide DDT was in use in North America. Some carry high levels of this pesticide in their bodies even today, perhaps because much of their songbird prey spends winters in South America, where DDT is still used. Sharp-shinned Hawks were once killed as vermin by bird enthusiasts trying to protect songbirds. These hawks do hunt birds at feeders, and the spread of backyard bird feeding may have helped populations of Sharp-shinned Hawks or allowed them to spend winters farther north than they used to.
- Bildstein, K. L., and K. Meyer. 2000. Sharp-shinned Hawk (Accipiter striatus). In The Birds of North America, No. 482 (A. Poole and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.
- Burrows, R., and J. Gilligan. 2003. Birds of Oregon. Lone Pine, Edmonton, Alberta, Canada.
Mueller, H.C. and D.D. Berger. 1970. Prey preferences in the Sharp-shinned Hawk: the roles of sex, experience, and motivation. Auk 87:452–457
- Peterson, R.T. 1990. Western Birds, Peterson Field Guides, third edition. Houghton Mifflin, New York.
- Sibley, D.A. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.
Resident to long-distance migrant. Sharp-shinned Hawks of the Appalachians and Western mountains may remain there year-round, whereas birds that breed in the northern U.S. and Canada leave their breeding grounds and may winter in the rest of the continental United States or migrate as far as southern Central America.
Backyard bird feeders do attract Sharp-shinned Hawks from time to time. Most bird watchers prefer to discourage this behavior, although studies indicate that feeders don’t greatly increase a bird’s chances of being taken by a Sharp-shinned Hawk—the hawks get the great majority of their diet elsewhere. If a hawk starts hunting regularly in your yard, the best thing to do is to take down your feeders for a couple of weeks. The hawk will move on and the songbirds will return when you put your feeders back up. Here’s more about how to cope with predators and pests in your yard.
Find This Bird
Look for these secretive hawks as they move across open areas with their characteristic flap-and-glide flight pattern. You’re most likely to spot Sharp-shinned Hawks during migration, especially fall migration, when they’re the most plentiful raptors seen at hawkwatch sites. Incredibly elusive while nesting, most Sharp-shinned Hawks spend their summers under the canopy of dense forests, occasionally coming into the open to circle in the sky or fly across a field. But they do also visit rural or suburban areas with some tree cover, especially where bird feeders or spilled grain encourage congregation of small birds.