The Cooper’s hawk is a medium-sized hawk found throughout North America. It is considered an accipiter, which is a type of hawk adept at flying swiftly through dense vegetation in pursuit of small bird prey. Cooper’s hawks have slate gray upperparts, pale underparts with reddish barring, and a long banded tail. Their size, shape, and behavior make them similar to other accipiter hawks.
Physical Characteristics
Cooper’s hawks are crow-sized raptors that measure 13 to 20 inches in length with a wingspan of 24 to 35 inches. Their relatively long tails and short, rounded wings allow for agile flight through congested habitats. Adult Cooper’s hawks have blue-gray upperparts, pale underparts with reddish barring, and dark bands on the tail. The eyes are red, and the legs and cere are yellow.
Immature Cooper’s hawks have brown upperparts with heavy streaks and a narrowly banded tail. Their underparts are white with brown streaking. As they mature, the streaking fades and the traditional adult plumage emerges over the course of several molts. In all plumages, males are smaller than females.
Some key physical similarities the Cooper’s hawk shares with other accipiters include:
| Compact body shape | Allows for quick maneuvers in dense habitats |
| Long tail | Enhances agility and serves as a rudder during flight |
| Short, rounded wings | Provides speed and ability to dart through vegetation |
| Long legs | Aid in capturing prey on the ground |
| Hooked beak | Tearing flesh of avian prey |
| Talons | Grasping and killing prey |
Hunting and Prey
Cooper’s hawks are ambush predators that hunt small birds and some mammals. They frequently hunt within the dense cover of treetops and vegetation, using obstacles to conceal their approach until prey is within range. When prey is spotted, the hawk executes a rapid burst of flight to overtake the target, grabbing it in midair or from a perch. Prey is then taken to a secluded location to be consumed.
Common prey items include doves, woodpeckers, jays, robins, and small rodents like squirrels and chipmunks. Less frequently, lizards, bats, and young rabbits may be taken. Cooper’s hawks often pluck feathers from avian prey before feeding. They usually dismember larger prey by separating wings, limbs, and head. Bones and other indigestible parts are later regurgitated as pellets.
Cooper’s hawks share similar hunting habits and prey preferences with other accipiters like:
| Sharp-shinned hawk | Specializes in catching small songbirds |
| Northern goshawk | Takes large birds, rabbits, and squirrels |
| Eurasian sparrowhawk | Feeds mostly on small birds like sparrows |
All are adept at navigating through vegetation to surprise and ambush unwary prey. Their diet tends to correlate with size, with larger accipiters able to take bigger prey. But they all exhibit a preference for capturing smaller birds, especially passerines.
Habitat
Cooper’s hawks are found year-round throughout most of the forested regions of North America. They occupy a variety of wooded habitats including deciduous, coniferous, and mixed forests. Parks, woodlots, and suburban areas with mature trees also provide good habitat.
These hawks nest in trees, building a new nest each year. The nests are typically 25 to 50 feet above ground, constructed of sticks and lined with bark strips and foliage. Nest sites are usually located near water and in areas with dense canopy cover.
In winter, Cooper’s hawks may roost communally in conifers or other sheltered sites. But they are otherwise solitary outside of the breeding season. Their habitat associations are similar to other accipiters such as:
| Northern goshawk | Conifer and mixed forests |
| Sharp-shinned hawk | Woodlands across North America |
| Eurasian sparrowhawk | Woodlands and forests of Europe/Asia |
All occupy the dense vegetation of natural woodlands across their respective ranges. This habitat provides concealment as well as abundant small bird prey.
Breeding
The breeding season for Cooper’s hawks runs from March to July. Courtship includes high circling flights and male food offerings to the female. The nest is constructed new each year, typically in a large deciduous or coniferous tree.
Females lay 3-6 pale bluish eggs that are incubated for 30-36 days. Hatchlings are brooded by the female while the male provides food. After about a month, the young leave the nest and learn to hunt over another few weeks. Cooper’s hawks first breed at 1-3 years old and may mate for life.
Reproductive similarities with other accipiters include:
| Clutch size | 3-6 eggs is typical |
| Nesting | Use a new stick nest each year |
| Chick rearing | Female broods, male provides food |
| Age of maturity | 1-3 years old |
The accipiters exhibit generally similar nesting habits and pair bonding behavior. Courtship flights, aerial stick transfers, new annual nests, and shared parental roles are common across the group.
Migration
Most Cooper’s hawks migrate out of northern and high elevation areas in winter. Migration begins in September and October, with peak activity in November. Northbound migration to the breeding grounds begins in March and April.
During migration, Cooper’s hawks stopover in areas with adequate food supplies and cover. Ideal stopover habitat provides dense vegetation for roosting and foraging along with abundant small bird prey. Some common migration strategies seen in Cooper’s hawks and other accipiters include:
| Stopovers | Brief stays in suitable habitat to rest and feed |
| Kettling | Soaring in groups to gain altitude |
| Coastal routes | Concentrated along coasts during migration |
| Partial migration | Some populations migrate while others are resident |
The bulk of the Cooper’s hawk population migrates south out of Canada and the northern U.S. But partial migration is seen, with some birds staying year-round provided adequate prey is available.
Taxonomy
The Cooper’s hawk belongs to the Accipitridae family, which includes hawks, eagles, kites, and allies. Their genus is Accipiter. The species name is cooperii, named after William Cooper, a New York zoologist.
Some close relatives in the Accipiter genus include:
| Sharp-shinned hawk | Smaller with more slender proportions |
| Northern goshawk | Larger and bulkier accipiter |
| Eurasian sparrowhawk | Old world counterpart to Cooper’s hawk |
These accipiters all share similar morphology and predatory habits. DNA analysis supports the close relationship, with Cooper’s hawks appearing most closely related genetically to the Eurasian sparrowhawk.
Status and Conservation
Cooper’s hawk populations declined in the mid 20th century due to the use of DDT and other pesticides. These chemicals accumulated in prey species that the hawks consumed, causing thin eggshells and reproductive failure. The banning of DDT allowed Cooper’s hawks to recover to sustainable population levels.
Current threats include habitat loss and fragmentation. Cooper’s hawks favor nesting near water sources, a habitat type that has declined. Conservation measures for Cooper’s hawks and other accipiters include:
| Habitat protection | Preserving intact forest tracts for nesting |
| Nest buffers | Protecting habitat around known nest trees |
| Reducing toxins | Restricting use of toxic chemicals like pesticides |
| Public education | Teaching public to appreciate raptor ecology |
Well-managed forests that retain mature trees and wetland areas provide the best habitat for Cooper’s hawks. Public support through awareness and habitat conservation is also critical to maintaining thriving Cooper’s hawk populations.
Conclusion
In summary, the Cooper’s hawk exhibits many similarities with its close accipiter relatives in terms of physical traits, hunting habits, habitat associations, migration ecology, breeding biology, and conservation status. Their compact shape, long tail, short wings, and other adaptations suit them for hunting agile avian prey through cluttered vegetation.
Across the Accipiter genus, these hawks play an important role as apex predators that help regulate songbird and rodent populations. Conservation of intact forests with minimal toxins and ample wetland areas can benefit Cooper’s hawks and other accipiters sharing these habitats. Their skill as aerial hunters continues to make cooper’s hawks and their accipiter kin vital components of healthy forest ecosystems.
