| Adult Broad-winged Hawks are brown above and rust colored below with prominent white barring. During flight the broad black bands on the tail are readily apparent. Immature birds are similar but lack the banding of the tail and are only sparsely spotted below. Secretive in nature this bird stays below the canopy and is usually detected by its thin "pe-heeee" call. The female is somewhat larger than the male, but otherwise they appear identical.
The breeding habitat consists of the deciduous woodlands usually near water in the eastern half of the United States and the eastern two thirds of southern Canada. When they migrate south, they do so in spectacular flocks, known as kettles, soaring high over head and numbering in the hundreds or even in the thousands in mid-September. The hawk depends on the thermals all year long but especially during migration. They will circle rising soaring higher and higher and then glide downward to the next thermal and begin to soar again. Because they depend on thermals, they r migrate over land as thermals usually do not develop over the oceans. They can be seen in their greatest numbers across the narrows of Panama as they migrate into South America. Thermals are especially prominent along ridges and areas like Hawk Mountain in Pennsylvania or Holiday beach in Michigan become prime observatories for these migrations. More than a half of million hawks will migrate over the southern coast of Texas.
Like the California Condor, the Red-tailed Hawk and other soaring birds the outer primary feathers can be extended creating slots between the wings and improving their aerodynamics. Aerial displays are performed during courtship, soaring in circles, and then suddenly darting at one another coming close to mid air collisions. The pair bonds sometimes last for several years.
The clutch consists of 3 or 4 white eggs, spotted with brown. The nest is usually located in the crotch of a tree, 15 to 50 feet above the ground and is a loose construction of sticks and dead leaves and lined with lichens and green leaves. The greenery that the bird places in the nest is thought to give some protection against parasites. Both birds gather sticks to build the nest but the female does most of the lining of the nest and sometimes old squirrel or crow's nest is used as a base. The nest is sometimes a flimsy structure and may give way during storms. Only the female has a brood patch and she begins to incubate the eggs immediately after the first egg is laid which leads to asynchronous hatching with the older birds sometimes dominating the younger ones. The female does almost of the incubation, while the male will bring her food. The eggs hatch after about one month. The female will brood continuously for the first week, but after that she will begin to hunt and only brood the young during inclement weather. The young will defecate over the edge of the nest and feces located on the ground can sometimes alert you to their presents. The young leave the nest about 35 days after hatching.
They hunt along the forest's edge or over open woodlands, and the diet consist mainly of snakes, mice, frogs and insects. Its dependence on mostly cold-blooded prey, explains the reason why it migrates fairly early in the fall. They sometimes will take the nestlings of smaller birds but usually cannot catch adult birds.
Length 13 to 19 inches.
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