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.Back to top
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.Back to top
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.
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.
|Clutch Size:||3-8 eggs|
|Number of Broods:||1 brood|
|Egg Length:||1.3-1.6 in (3.3-4.2 cm)|
|Egg Width:||1.1-1.3 in (2.8-3.4 cm)|
|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.|
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.Back to top
Sharp-shinned Hawk numbers have remained relatively stable between 1966 and 2019, according to the North American Breeding Bird Survey. Populations estimates are made from yearly migration counts, because these birds are so solitary and elusive at their deep-forest breeding sites that scientists have little data on their nesting success. Partners in Flight estimates a global breeding population of 1 million and rates them 7 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. However, the Puerto Rican Sharp-shinned Hawk is federally listed as Endangered and do not migrate. This small population took a big hit in Hurricanes Irma and Maria from deforestation caused by the storms.
Sharp-shinned Hawks only breed in dense stands of trees, and their fate is intertwined with that of wooded wilderness. Like other birds of prey, they 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.Back to top
Bildstein, Keith L. and Kenneth D. Meyer. (2000). Sharp-shinned Hawk (Accipiter striatus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
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.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Peterson, R. T. (1990d). A Field Guide to western birds. Boston, MA: Houghton Mifflin Co.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.