Their main food in the United States in summer is large insects, especially grasshoppers. In winter, when insects are more scarce, they turn to mice and sparrow-sized birds, sometimes giving them the name sparrowhawk. They may also take sandpiper chicks and, in some places, lizards, scorpions and amphibians. In the extreme north of their range, in heavy snow, they specialize in house sparrows and house mice.

They lay between 3 to 7 white, cream, or pinkish-white eggs with fine brown specks and spots. Markings are often more dense on one end of the egg and sometimes form a wreath.

Length: 8 1/2 to 9 1/2 inches

Wingspan: 21 inches

Habitat: Open deserts, semi-open areas and the edges of groves. It needs trees in order to nest (generally in holes in trees) but will use holes in other structures where no trees exist.

Voice: A noisy bird. Its high pitched cries of excitement, alarm or irritation are often heard (three to six bursts of "klee"). A high-pitched whining cry when near the nest, and a rapid chittering when the pair approach one another or are on the nest, or feeding their young.

Other Behavior: Short distant migrant. An alert, noisy, suspicious little bird, its constant high-pitched cry of alarm annoying, especially when a pair are shadowing their newly-fledged young, or when harrying a larger bird of prey.