Mating and nest building begin in early spring, usually in March. This is accompanied by spectacular aerial displays by both males and females. Circling and soaring to great heights, they fold their wings and plummet to treetop level, repeating this display as much as five or six times.

Nests are located from 35 to 75 feet high in the forks of large trees. The nest is large, flat, shallow and made of sticks and twigs about 1/2 inch in diameter. Both males and females assist in nest construction. Nest sites may be used from year to year, since there is strong evidence that hawks mate for life. If the old nest is wind damaged, layers of new nesting material are added each year.

The female usually lays 2 dull-white to bluish-white eggs that are marked with a variety of irregular reddish spots and splotches. Incubation takes 28 days and is maintained almost entirely by the female. During this period the male hunts for both of them, bringing her food to the nest.