Cooper’s Hawk

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The Forest Hawks (accipiters): distinctive as a pair, but very similar, the Cooper’s Hawk and Sharp-shinned Hawk are built to pursue small birds in forested areas. They have relatively short wings and long tails. As with most raptors, the females are larger than the males, but in accipiters it is most striking. Like Red-shouldered Hawks, these birds have a distinctive flight style, with numerous quick flaps, followed by short periods of gliding.
Cooper’s Hawk (Accipiter cooperii): the larger of the pair, this species is a year-round resident, with a big influx to our area in winter. They are regularly seen raiding backyard bird feeders—for their birds. They are regular breeders in suburban areas.

Adult Cooper’s Hawk. Photo by Ed Harper.

These striking adults are seen less often than immatures, and are usually less approachable. Note the long tail, distinctive of accipiters. The fluffy white undertail feathers can wrap around the sides of the tail, and appear to show a white rump—which sometimes leads to them being incorrectly identified as Northern Harriers. Cooper’s Hawks average about the size of a crow.
Compared to Sharp-shinned Hawks, this species has a flatter head and a dark crown that contrasts with a paler nape.

Juvenile Cooper’s Hawk. Photo by Ed Harper.

Juveniles of both species are also very similar. Cooper’s Hawks usually show a rounder tail than the more squared-off tail of Sharp-shinned, but this feature has been overemphasized. Cooper’s have finer streaks on the breast, typically becoming fewer in the lower belly.

Juvenile Cooper’s Hawk. Photo by Ed Harper.

When seen from below, the leading edge of the wings produce a straighter line than Sharp-shinned, with the head clearly protruding.
Sharp-shinned Hawk (Accipiter striatus): the smaller of the pair. Does not breed at low elevations, but fairly common from fall through early spring.

Adult Sharp-shinned Hawk. Photo by Chris Conard.

This species has a rounder head than Cooper’s, with an eye appearing larger and positioned more in the middle of the head (as opposed to closer to the bill in Cooper’s).

Juvenile Sharp-shinned Hawk. Photo by Ed Harper.

Overhead, the wings push forward, and a smaller looking head projects less beyond the wings than in Cooper’s. A more heavily streaked breast, often with broader, blurrier streaks. Sharp-shinneds usually appear more compact than Cooper’s, with Cooper’s seeming lankier and proportionally longer-tailed. The smaller Sharp-shinned Hawks have extremely quick flaps, faster than a Cooper’s.
Tail shape: the outer tail feathers on a Cooper’s are shorter than the middle tail feathers, which leads to more rounded tail shape. On a perched bird, you can often see the shorter tail feathers overlapping longer feathers. Cooper’s usually show a broader white tail tip. Worn weathers can lose the standard shape and white tip. Basing an identification solely on tail shape is risky.
Size and accipiter identification: if you see an accipiter that appears tiny, it is very likely a Sharp-shinned Hawk. If it appears very large, it is very likely a Cooper’s Hawk. Male Cooper’s Hawks and female Sharp-shinned Hawks can be very near the same size. Many accipiters are not seen well enough to confidently identify. Some are seen very well, and still are frustratingly difficult.
Northern Harrier (Circus cyaneus): this distinctive species, formerly known as the “Marsh Hawk,” is seen in open fields and wet areas. Males are gray and females are brown. Juveniles are similar to females, but are redder below.

Male Northern Harrier. Photo by Dan Tankersley.

Male Northern Harrier. Photo by Dan Tankersley.

Note the long tail, and long wings. No other raptor in our area shows this silhouette. They are expected to be flying low over fields, but commonly soar higher, which confuses some observers.

Female Northern Harrier. Photo by Dan Tankersley.

The white “rump” is an overly emphasized feature; however, all Northern Harriers (male, female, juvenile) show this feature prominently. If the bird lacks a white “rump,” it is not a Northern Harrier. Beware that this feature can be shown by Swainson’s Hawks (see above), immature Red-tailed Hawks, as well as Ferruginous Hawks and Rough-legged Hawks.

Juvenile Northern Harrier. Photo by Ed Harper.

Immature Northern Harrier. Photo by Chris Conard.

Note the owlish face. The feathered disk-shaped face concentrates sound and helps them hear prey in the vegetation, like a Barn Owl.
White-tailed Kite (Elanus leucurus): a common year-round resident. Often seen hovering over open fields, looking for small rodents. When flying fast, they can resemble a falcon, with their wings that taper to a point. With a good view, they are very distinctive.

White-tailed Kite hovering. Photo by Chris Conard.

Recently fledged White-tailed Kites show a rusty collar. Photo by Chris Conard.

Eagles: the two species, Golden Eagle and Bald Eagle, are rare to uncommon in our area. Size can be difficult to judge in the field, so structural cues are most helpful in identifying them.
Golden Eagle (Aquila chrysaetos):

Golden Eagle. Photo by Chris Conard.

This species can be confused with buteos and with Turkey Vultures. Immatures have white near the base of the tail and white patches in the underwings.
Bald Eagle (Haliaeetus leucocephalus): adults seen well are unmistakable.

Immature Bald Eagle. Photo by Ed Harper.

Young birds are often heavily mottled below. Note the massive bill and tail proportionally shorter than a Golden Eagle’s. The head and tail project about the same distance beyond the leading and trailing edge of the wings.
Osprey (Pandion haliaetus): this fish specialist is distinctive. It has a gull-like silhouette, with slightly bent wings, and dark patches on the “wrists.” When perched, with its dark back and (partially) white head, it can be mistaken for a Bald Eagle when seen at a distance.

Osprey with fish. Photo by Chris Conard.

Falcons: fast flyers with pointed wings. Only the American Kestrel is common in our area.
American Kestrel (Falco sparverius): our smallest falcon. It is often seen on roadside wires and is common year-round.

Male American Kestrel. Photo by Chris Conard.

Males have slate-colored wings, a thick bar at the end of the tail, and a spotted breast. Females have rufous wings, multiple bars on the tail, and a streaked breast.

Female American Kestrel. Photo by Dave Johnson.

Kestrels often hover, and when they land, they bob their tails.
Merlin (Falco columbarius): an uncommon winter visitor to a variety habitats from grasslands to areas where there are concentrations of shorebirds. A very fast and powerful flyer. Much stockier than a kestrel. Does not hover.

Merlin. Photo by Chris Conard.

This species flies like a small version of a Peregrine Falcon. Wing beats are much crisper and more powerful than a kestrel’s. They often make a quick pass through an area and leave as fast as they arrived.
Peregrine Falcon (Falco peregrinus): an uncommon species in our area, but one that can be seen nearly year-round. It is often associated with waterfowl and shorebirds, but can be seen anywhere. Dark “helmet” distinctive.

Peregrine Falcon. Photo by Chris Conard.

Peregrine Falcon. Photo by Marin Meyers.

Showing the classic falcon silhouette, with pointed wings. This and the following species fly with stiff, powerful wingbeats.

Prairie Falcon (Falco mexicanus): similar in size and structure to a Peregrine Falcon. This is a regular visitor to grassland areas in winter. In flight, it shows distinctive dark “wing pits.”

Prairie Falcon. Photo by Walt Carnahan.

Prairie Falcon. Photo by Chris Conard.

Paler above than a Peregrine Falcon, and lacks the dark “helmet.”
Vultures: the Turkey Vulture is the only vulture in our area, and along with the California Condor, one of only two in the state. Turkey Vultures--along with American Crows, Common Ravens, and Rock Pigeons—are among the few non-raptors that can be mistaken for one.
Turkey Vulture (Cathartes aura): a common to abundant year-round presence. They can appear very hawk-like. The silvery flight feathers are distinctive in good light. Unsteady in the air, they rock side to side like a Swainson’s Hawk. Long “fingers” at wing tips distinctive, though reminiscent of Golden Eagles.

Turkey Vulture. Photo by Chris Conard.

Many volumes have been written about raptor identification. The collection of photos and text above is merely a short primer. Thank you to all of the photographers who generously allowed the use of their photos.
Recommended further reading:
1. National Geographic Field Guide to the Birds of North America.

2. The Sibley Guide to Birds. David Allen Sibley.

3. Hawks in Flight. Pete Dunne, David Sibley, and Clay Sutton.

4. Raptors of Western North America. Brian K. Wheeler.

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