Male vs Female Cooper's Hawk: How to Tell Them Apart

A female Cooper's Hawk is about a third bigger than a male, one of the biggest size gaps between the sexes in the hawk family. Adults differ a little in color too: males are usually bluer above, with a blacker cap and gray cheeks, and females browner, with brown cheeks. Young birds look alike, so for them size, and the shape of the tail, are the clues.¹ This page covers how to tell them apart and how males and females differ in what they do. For the bird in full, see the Cooper's Hawk guide.

The main differences, side by side.

About a third bigger overall, though the gap differs by measure.¹ In length it is smaller: a female is 16.5–17.7 inches (42–45 cm) long and a male 14.6–15.3 inches (37–39 cm). In weight it is bigger: 11.6–24.0 ounces (330–680 g) for a female against 7.8–14.5 ounces (220–410 g) for a male.^{2, 3} In Wisconsin, where breeding birds were weighed, the two did not overlap at all: males weighed 9.7–12.9 ounces (275–366 g) and females 17.0–23.5 ounces (482–667 g), averaging 11.5 ounces (327 g) and 20.5 ounces (580 g), so females were nearly 1.8 times as heavy. Her wings and tail are longer too: a folded wing, measured from the bend to the tip, of 10.5 inches (266.8 mm) against 9.3 inches (236.9 mm), and a tail of 8.3 inches (210 mm) against 7.3 inches (185 mm).¹ Birds in the West are smaller than in the East, so the figures shift by region.^{1, 2}

Size is the best clue but is hard to judge on a lone bird. It is also where Cooper's Hawks get mixed up with Sharp-shinned Hawks: a male Cooper's is close to a female Sharp-shinned in size, though their overall lengths do not overlap.^{4, 5} More in Cooper's Hawk or Sharp-shinned Hawk?

Adults look alike at a glance, but males are brighter and more contrasting. A male's back is blue-gray; a female's is brown to grayish-brown. The male's cap is charcoal to black, set off sharply from a gray nape, and older males have gray cheeks; a female's cap is brownish-gray to blackish, and her cheeks are brown or reddish. The male's barring below is a brighter reddish.¹ Because the sexes are so similar, these marks work best together with size.

In both sexes the eye darkens with age, from yellow through orange to red. Males average darker eyes than females of the same age, and many adult females never reach deep scarlet. Birds of the same age vary, though, so eye color is a hint rather than proof.¹

Mostly by size. Young males and females look alike in their brown, streaked plumage; females are bigger, with longer tails that are more rounded at the tip.¹ More on young birds in Juvenile Cooper's Hawks.

The male builds most of the nest, 70% of it in Wisconsin, and from about a month before laying until the chicks are half-grown he brings nearly all the food for the female and the young. The female incubates, broods and feeds the chicks bill to bill.¹ More in Cooper's Hawk nesting.

In a pair, the bigger female dominates: she displaces the male from prey, perches and the nest. The smaller male is submissive and listens for the female's reassuring calls.^{1, 2}

Both molt between May and October, but the female starts first, about when she begins incubating, and the male 7–14 days later. While there are chicks to feed, about 62% of females and 29% of males pause their molt.¹

Most Cooper's Hawks first breed at 2, but some one-year-old females breed, still in their brown first-year feathers: they make up 16–25% of breeding females in long city studies. One-year-old males rarely do, just 2% of 732 in Wisconsin.¹

Both sexes give the cak-cak-cak alarm call near the nest. The male's most frequent call is a kik, which announces him to the female when he comes in with food; a whaaa is given mainly by females, as she flies to him for food. The male's voice is generally higher, a little faster and less harsh. One detailed study described 42 different calls given by females and 22 by males.¹ In the recording below, a female calls near her mate in Seattle in late April.⁶ More: Cooper's Hawk sounds, with recordings.

Females often take bigger prey than males, though not always. In rural Florida, males hunted all year in a home range centered on the nest, while females roved widely, to chicken farms and bird feeders. In a study of 8 city hawks in Indiana, the females never attacked House Sparrows and the male rarely did.¹

In fall, females migrate a few days before males; in spring, males come back first. In Wisconsin, breeding males stayed faithful to their nesting area for life, while 23% of experienced females in Wisconsin moved to another one in a later year. Young females also settle farther from where they hatched: about 17 miles (27.6 km) on average in Wisconsin, against 4.5 miles (7.2 km) for males.¹

1. Rosenfield, R. N., Madden, K. K., Bielefeldt, J., Curtis-Scott, O. E. (2025). Cooper's Hawk (Astur cooperii), version 1.2. Birds of the World (P. G. Rodewald, editor). Cornell Lab of Ornithology. doi:10.2173/bow.coohaw.01.2
2. Cornell Lab of Ornithology. Cooper's Hawk. All About Birds. Accessed 30 October 2026. Source
3. National Audubon Society. Cooper's Hawk. Guide to North American Birds. Accessed 30 October 2026. Source
4. Project FeederWatch. Tricky Bird ID: Sharp-shinned Hawk and Cooper's Hawk. Project FeederWatch (Cornell Lab of Ornithology and Birds Canada). Accessed 30 October 2026. Source
5. Bildstein, K. L., Meyer, K. D., White, C. M., Marks, J. S., Kirwan, G. M. (2020). Sharp-shinned Hawk (Accipiter striatus), version 1.0. Birds of the World (S. M. Billerman et al., editors). Cornell Lab of Ornithology. doi:10.2173/bow.shshaw.01
6. Tuoichen (2020). Cooper's Hawk calls, Discovery Park, Seattle, Washington, 26 April 2020. iNaturalist sound 77038. Accessed 30 October 2026. Source