After mating, the female lays 3-8 eggs (usually 4-6) in April and May. Eggs are oval, bluish-green, and blotched and spotted with brown and gray. The young hatch following an 18-day incubation period.

Crows are both predators and prey. As predators, they rob nests of songbirds and waterfowl, killing and eating newly hatched young, or cracking eggs. As prey, young crows and unhatched crow eggs are eaten by raccoons, opossums and tree-climbing snakes. Hawks and owls kill fledgling and adult crows. Crows are especially vulnerable to night attacks by great horned owl.

Crows are curious. Shiny objects fascinate them, and they have been known to fly off with bits of glass, rings, keys, etc. Crows exhibit their intelligence by imitating a large number of sounds, including whistles, cats, machines and the human voice. Crows have a good vocabulary -- a wide range of caws, crowing noises, coos, and other soft, melodious sounds they use to communicate with each other.

The raven is often confused with its close relative, the crow, but there are major differences between the two species that are especially apparent when crows and ravens are seen together. Ravens eat rodents, insects, grain, fruit, bird eggs and refuse. They consume much carrion, especially in winter. In northern Pennsylvania, they are often seen along Interstate 80, where they feed on road-killed deer, raccoons, opossums, etc. Ravens also prey upon sick and injured animals.

A raven is every bit as alert as a crow and possesses sharp eyesight and hearing. Ravens are considered among the most intelligent of all birds; like crows, they can learn to imitate a variety of sounds, including the human voice. In nature, their calls include guttural croaks, gurgling noises, and a sharp, metallic "tock."