Scientific name – ” Accipiter cooperii “
Cooper’s hawks are medium-sized North American birds of prey that stem from the Accipiter genus. Out of fifty-one accipiter hawks worldwide, there are three North American accipiters. The other two are the northern goshawk ” Accipiter gentilis ” and the sharp-shinned hawk “ Accipiter striatus. ”
Cooper’s hawks were given their common name in 1828 by Charles Lucien Bonaparte in honor of his fellow ornithologist and naturalist William Cooper. This bird’s other common names are chicken hawk, quail hawk, big blue darter and swift hawk.
Cooper’s hawk breeding populations range in North America from southern Canada to Mexico. Migratory populations winter throughout Mexico and as far south as Central America.
Cooper’s Hawk Characteristics
Phenotypically, cooper’s hawks are almost identical to sharp-shinned hawks, aside from the fact that they are larger. They share many common traits with the northern goshawk too. Their construction is similar to all accipiter hawks in that they have a proportionately longer tail and short, broad rounded wings.
Cooper’s Hawk Size
These are medium-sized birds. For a means of comparison, adult cooper’s hawks are about the size of a crow. They are sexually dimorphic with a sometimes-stark size difference between the sexes. A large female can be up to 1/3 larger than a small male cooper’s hawk. Their adult size also varies with geographic location. For instance, cooper’s hawks in eastern North America are larger than those in western North America. The dividing line being the Rocky Mountains.
Along this line, The average weight of male cooper’s hawks ranges from 9.88 oz. ” 280 g ” in western males and 12.3 oz. ” 349 g ” for eastern males. What’s more, the average weight of females ranges from 15.5 oz. ” 439 g ” for western females to 1.25 pounds ” 566 g” for eastern females. Collectively, their average length is13 3/4 to 18 inches ” 35 to 46 cm ” for males and 16 1/2 to 19 3/4 inches ” 42 to 50 cm.” for females. Cooper’s hawks have a wingspan of 75 to 94 cm. Source
Cooper’s Hawk Coloration
Adult cooper’s hawks have brownish grey or blue-grey upper parts with a black cap on the head. Additionally, they have reddish-brown bars on their chest and white underparts. What’s more, their tail is bluish grey with three black bands. The last black band on their tail ends with a distinctive white tip. The crown of their head is black. Additionally, they have a hooked bluish-black beak adapted for tearing apart prey. Their feet and legs are yellow, while their talons are black. Source
Juvenile cooper’s hawks are dark brown above with whiteish mottling. Their tail is also brown with four contrasting dark brown bands. The crown of their head is brown rather than black.
The eye color of these birds morphs as they mature. The first eye color immature birds have is blue-grey when they are nestlings. As the get a little older they have yellow eyes, then orange eyes as they get their flight feathers. Adult Cooper’s hawks usually have red eyes.
Cooper’s Hawk Range
Breeding Range
The range of breeding populations of cooper’s hawks goes from southern Canada through the forty-eight conterminous United States. From there, it goes into northern Mexico.
Winter Range
Most cooper’s hawks winter somewhere within their summertime range. However, northern birds do migrate to the south and birds that are in the most extreme southern reaches of their range migrate to the north in the spring. Most cooper’s hawks winter within the United States and Mexico. However, they go as far to the south as Costa Rica, Panama, and Columbia in some cases. Source
Cooper’s Hawk Habitat
Cooper’s hawks primarily nest in mature forest habitats. They will nest in either coniferous or deciduous trees, with their preference leaning towards deciduous. In the northwestern and northeastern U.S, they prefer conifers. Elsewhere in between, they prefer broad-leafed trees. They will also inhabit mixed coniferous, deciduous wooded areas. In southern Canada, their breeding habitat extends into the south end of the Taiga.
They construct their nests in the crotch of the tree or on a horizontal limb near the trunk, 6 to 18 meters above the ground.
In the northwest, cooper’s hawks may prefer north and west-facing slopes since they are slightly cooler. Additionally, in the northwest, where they share habitat with northern goshawks, cooper’s hawks seem to inhabit groves of intermediate-sized trees that are 50 to 60 years old, while the goshawk inhabits the older and taller groves.
Although they are traditionally a shy, secretive forest raptor, coopers’ hawks have proven that they are adaptable. In suburban areas and residential areas, they inhabit fragmented woodlands. Source
What Do Cooper’s Hawks Eat?
Cooper’s hawks are birds of prey. They feed on quail, grouse, pheasants, and smaller birds such as American robins, meadowlarks, and blue jays. They often catch birds on the ground or a perch from ambush. What’s more they often catch birds in flight. Small mammals such as ground squirrels, tree squirrels, bats, mice, and voles are also a mainstay of their diet. They also prey on a variety of other small mammals, reptiles, and amphibians.
Cooper’s Hawk Predators
Great horned owls, northern goshawks, and red-tailed hawks are all a threat to prey on cooper’s hawk eggs, nestlings, and adults. What’s more, Raccoons and American crows are a threat to feed on cooper’s hawk eggs and nestlings. Source
Cooper’s Hawk Behavior
Cooper’s hawks do some interesting things when they’re sleeping. One of them is to stand on one foot. The other is to tuck their head between their shoulder blades underneath their ruffed-up scapular feathers. This gives them a grotesquely headless appearance. This is a habit they share with other birds, including other hawks.
On rare occasions, juvenile cooper’s hawks will lie on their backs on a tree branch to sun themselves.
Cooper’s Hawk Hunting Behavior
Cooper’s Hawk’s prefer to hunt from a high perch vantage point where they silently survey their surroundings. When they spot their prey, they approach stealthily, using any available cover, and then put on a short, devastating burst of speed. Their eyes are designed to provide excellent depth perception. This makes them good at catching prey at top speed. They are persistent in their attack and are not averse to pursuing prey on foot into the underbrush if their initial attempt fails.
Cooper’s hawks catch most of their prey on the ground or a perch, but they also catch birds in flight. They have the speed and maneuverability to do so. Their powerful, rounded wings propel them forward at high speed, while their proportionately long tail acts as a rudder to help them negotiate the twists and turns they have to make when pursuing prey.
Cooper’s Hawk Mating Behavior
Cooper’s hawks are generally monogamous unless one mate dies. Breeding season is generally April through July in most of their territory. However, the breeding season may begin as early as February in the southern U.S and Mexico.
When courting, male cooper’s hawks perform ritualistic circling flights above their intended nesting area or sky dances with exaggerated high arching wing strokes and slow rhythmic flapping.
The mated pair will either repair an old nest or build a new one. If they opt for a new nest, the building process generally takes about two weeks. As earlier noted, they will nest in either deciduous or evergreen trees, with a slight preference given to the former over most of their range. They build a stick nest. This nest will be constructed out of sticks that are less than an inch in diameter and lined with bark chunks and greenery. Furthermore, their nest will either be located in the tree crotch or on a large horizontal branch close to the trunk and up to 60 feet off the ground.
Cooper’s hawks produce one brood per year. Their clutch size ranges from 3 to 5 eggs. Their incubation period is 30 to 36 days. The female does all the incubating except for 10-to-30-minute periods of time when the male will substitute for the female after he has brought her food. He brings the food to an adjacent perch, and the female leaves the nest to consume it while the male takes her place.
Cooper’s Hawk Life History
Cooper’s hawk Hatchlings are born altricial or in an immature helpless condition. They have to be reared for a time in the nest, as opposed to precocial hatchlings that are born able to leave the nest and feed themselves almost immediately after they dry off after birth. It takes 27 to 34 days for them to fledge with males fledging sooner than females.
They may start to hunt for themselves after about eight weeks of age, but most of them will still depend on their parents for food.
Generally speaking, cooper’s hawks will first breed at two years of age.
In the wild, their average life expectancy is 12 years. However, the oldest recorded wild bird was 20 years and 5 months of age.
