A mated pair will either remodel an old nest or build a new one, occasionally starting on top of a squirrel or crow nest. The female may begin incubation before the last egg is laid, resulting in young of different sizes in the same brood. The female does most of the incubating and is supplied with food by the male. After about two weeks, when the young no longer require constant brooding, the female joins the male in hunting to feed them. The young soon learn to tear meat apart and feed themselves.
Hawks help control insect, rodent and small bird populations.
They're a natural predatory force that improves a prey species by making it develop alertness, speed and other survival attributes, and by weeding out unfit individuals. Hawks are also environmental indicators. Many hawks fly south each autumn. The species migrating in greatest numbers are often those that cannot find adequate food supplies in winter. In our state, many migrating birds follow ridges paralleling the Allegheny Plateau, climbing high on thermals that rise along these ridges.