Cooper's Hawk Accipiter cooperii Scientific name definitions

The Cooper's Hawk is a crow-sized raptor that breeds in deciduous and mixed-deciduous forests throughout the United States, southern Canada, and northern Mexico. Across this broad distribution, which is expanding northward and southward, it is an inconspicuous species. However, since the 1970s, Cooper's Hawks have commonly nested in suburban and urban landscapes, such that it is likely the most common backyard breeding raptor across North America. It also is a frequently observed bird of passage at autumnal migration watchsites, locations where raptors concentrate in migration. The female Cooper's Hawk is about one-third larger than the male, and indeed this species shows among the greatest reversed size dimorphism of any of the world's hawks. Vocalizations, especially by the female, may be an important element of the pair bond in this highly dimorphic species. Midway in size between the larger American Goshawk (Accipiter atricapillus) and the smaller Sharp-shinned Hawk (Accipiter striatus), the Cooper's Hawk, like these other accipiters, has short, powerful, rounded wings and a relatively long tail that ensures marked maneuverability in its quick pursuit of birds and mammals.

The Cooper's Hawk breeds in both extensive areas of forest and smaller woodlots, as well as in pine plantations, and suburban and urban woodlands of towns and cities of all sizes. It also nests at high densities in the small wooded tracts in grasslands of the Northern Great Plains. It captures a variety of prey, mainly medium-sized, shrub- and ground-dwelling birds and mammals such as doves, jays, robins, chipmunks, and other rodents.

Some eastern populations of the Cooper's Hawk declined significantly in the mid-1900s, owing to shooting, trapping, and pesticide contamination. Many states in the eastern United States and some Canadian provinces designated the species as Threatened or Endangered in the late 1900s, but such designations were rescinded as evidence of widespread recovery of breeding populations.

Population trends generated from migration count data are available from Hawk Mountain Sanctuary and Cape May (see Table 1 ). Rosenfield (1 Rosenfield, R. N. (2018). The Cooper’s Hawk: Breeding ecology and natural history of a winged huntsman. Hancock House, Blaine, WA, USA. Close ), Rosenfield et al. (2 Rosenfield, R. N., L. J. Rosenfield, J. Bielefeldt, R. K. Murphy, A. C. Stewart, W. E. Stout, T. G. Driscoll, and M. A. Bozek (2010). Comparative morphology of northern populations of breeding Cooper's Hawks. Condor 112:347–355. doi:. Close ), and McConnell (3 McConnell, S. (2003). Nest site vegetation characteristics of Cooper’s Hawks in Pennsylvania. Journal of the Pennsylvania Academy of Science. 76(2–3):72–76. Close ) provided good summaries of changes in the species' distribution and abundance (see also 4 González-Oreja, J. A., I. Zuberogoitia, and F. J. Jiménez-Moreno (2019). First Record of Coopers Hawk (Accipiter cooperii) Breeding in Puebla, Mexico. Journal of Raptor Research 53:215. Close ). Since the 1990s, there have been concerted efforts to document habitat use in various parts of the species' range, with some emphasis on differences in the quality of nesting habitat (indexed by density and productivity) in natural versus human-altered landscapes (e.g., suburbia, plantations). Studies of this type have occurred in Arizona (5 Boal, C. W., and R. W. Mannan (1999). Comparative breeding ecology of Cooper's Hawks in urban and exurban areas of southeastern Arizona. Journal of Wildlife Management 63:77–84. Close , 6 Boal, C. W., and R. W. Mannan (2000). Cooper's Hawks in urban and exurban areas: a reply. Journal of Wildlife Management 64:601–604. Close ) and Wisconsin (7 Rosenfield, R. N., J. Bielefeldt, J. L. Affeldt, and D. J. Beckmann (2000). Urban nesting biology of Cooper's Hawks in Wisconsin. In Raptors in Human Landscapes: Adaptations to Built and Cultivated Environments (D. M. Bird, D. E. Varland, and J. J. Negro, Editors). Academic Press, London, United Kingdom. pp. 41–44. Close , 1 Rosenfield, R. N. (2018). The Cooper’s Hawk: Breeding ecology and natural history of a winged huntsman. Hancock House, Blaine, WA, USA. Close ). Detailed information on nest-site use and selection is available for New Jersey and New York (8 Bosakowski, T., D. G. Smith, and R. Speiser (1992). Nest sites and habitat selected by Cooper's Hawks, Accipiter cooperii, in northern New Jersey and southeastern New York. Canadian Field-Naturalist 106:474–479. Close ), New Mexico (9 Siders, M. S., and P. L. Kennedy (1994). Nesting habitat of Accipiter hawks: is body size a consistent predictor of nest habitat characteristics? Studies in Avian Biology 16:92–96. Close ), Arizona (10 Boal, C. W., and R. W. Mannan (1998). Nest site selection by Cooper's Hawks in an urban environment. Journal of Wildlife Management 62:864–871. Close ), Wisconsin (11 Trexel, D. R., R. N. Rosenfield, J. Bielefeldt, and E. A. Jacobs (1999). Comparative nest site habitats in Sharp-shinned and Cooper's Hawks in Wisconsin. Wilson Bulletin 111:7–14. Close ), Pennsylvania (3 McConnell, S. (2003). Nest site vegetation characteristics of Cooper’s Hawks in Pennsylvania. Journal of the Pennsylvania Academy of Science. 76(2–3):72–76. Close ), and North Dakota (12 Nenneman, M. P., T. A. Grant, M. L. Sondreal, and R. K. Murphy (2003). Nesting habitat of Cooper's Hawks in northern Great Plains woodlands. Raptor Research 37:246–252. Close ). An ongoing 40-year study in Wisconsin has described nesting chronology, productivity, annual adult survival rates, dispersal, habitats and breeding density (13 Bielefeldt, J., R. N. Rosenfield, W. E. Stout, and S. M. Vos (1998). The Cooper's Hawk in Wisconsin: a review of its breeding biology and status. Passenger Pigeon 60:111–121. Close , 1 Rosenfield, R. N. (2018). The Cooper’s Hawk: Breeding ecology and natural history of a winged huntsman. Hancock House, Blaine, WA, USA. Close , 14 Rosenfield, R. N., M. G. Hardin, J. Taylor, L. E. Sobolik, and P. N. Frater (2019). Nesting density and dispersal movements between urban and rural habitats of Cooper's Hawks (Accipiter cooperii) in Wisconsin: are these source or sink habitats? American Midland Naturalist 182:36–51. Close ), including long-term responses of breeding birds to recent climate change (15 Rosenfield, R. N., M. G. Hardin, J. Bielefeldt, and E. R. Keyel (2016). Are life history events of a northern breeding population of Cooper's Hawks influenced by changing climate? Ecology and Evolution 7:399–408. Close ) and genetic and morphological variation among northern populations (2 Rosenfield, R. N., L. J. Rosenfield, J. Bielefeldt, R. K. Murphy, A. C. Stewart, W. E. Stout, T. G. Driscoll, and M. A. Bozek (2010). Comparative morphology of northern populations of breeding Cooper's Hawks. Condor 112:347–355. doi:. Close , 16 Sonsthagen, S. A., R. N. Rosenfield, J. Bielefeldt, R. K. Murphy, A. C. Stewart, W. E. Stout, T. G. Driscoll, M. A. Bozek, B. L. Sloss, and S. L. Talbot (2012). Genetic and morphological divergence among Cooper's Hawk (Accipiter cooperii) populations breeding in north-central and western North America. Auk 129:427–437. Close ).

The species was named in 1828 by Charles Bonaparte (American Ornithology) for his friend and fellow ornithologist, William C. Cooper, a New York scientist and father of James C. Cooper, who was later honored in the title of the Cooper Ornithological Society (17 Mearns, B. C., and R. F. Mearns (1992). Audubon to Xántus: The lives of those commemorated in North American bird names. Academic Press, New York, NY, USA. Close ).