Although when habitat doesn't provide sufficient sites, several pair will build their nests in the same location. A typical nest contains four or five drab olive or blue-green eggs that may be speckled or streaked. It's thought that parents share the incubation duty. Eggs hatch in about 18 days, and the young fledge in just over a month. In the nest the young depend on their parents and older siblings for food.
Crows roost in large numbers to protect themselves from predators.
Enemies include great horned owls, red-tailed hawks, raccoons and opossums. By gathering together, crows find safety in numbers. Crows have a cooperative defense behavior known as mobbing. If one crow sees a predator, it will give an assembly call. Every crow within earshot will quickly fly to the source and attack the predator.