Crows are among the world's most adaptable and intelligent birds. For example, crows are able to recognize individual human faces, solve simple problems and use simple tools. Watch this example. They have evolved a varied language, and are capable of mimicking sounds they hear, including other animals. They also learn to associate noises with specific events, especially with food distribution.
Crows live in diverse habitats across North America. They thrive close to humans in cities and suburbs. They roost at night in large flocks of up to several thousand during the winter. During the day, smaller groups may fly up to 50 miles in pursuit of food.
With a preference for coniferous trees like firs, crows build their nests in woods or isolated trees at least 60 feet above ground. Nests are solidly built of branches and twigs and are lined with bark, plant fibers, mosses, twine, and other found materials.
As omnivores, crows eat whatever is available, including insects, small amphibians and snakes, earthworms, eggs, nesting birds, and saltwater invertebrates such as clams and mussels. They also scavenge dead animals and garbage and eat wild and cultivated fruits and vegetables.
Paired male and female crows together incubate their four to six eggs, which hatch in 18 days. The young first fly when they are about one month old. Frequently at least one young bird will remain with her parents through the next nesting season to help care for the new nestlings, by bringing them food and guarding the nest.
In recent years, crow populations have expanded in urban and suburban areas in the Northwest. Wildlife biologists suggest that the increase will soon level off. Although crows can find unlimited food sources, they have begun to run out of potential nesting sites.
Crows have survived centuries of efforts by humans to eradicate them. They have been shot, poisoned, and bombed, but they have endured and even expanded their range.
Common complaints about crows include:
Most people may not know that crows can actually benefit agriculture by eating insects and larvae that damage crops.
Crows are attracted to food scraps in garbage cans and compost piles, and easy pickings in gardens. Make it as hard as possible for them to raid.
While crows have young in the nest and on the ground learning to fly, they may defend their nesting territory by dive-bombing other animals and people. This territorial behavior is only temporary and will quickly subside as the young fledge from the nest and learn to fly. If possible, it is best to stay away from nesting areas until the young have fledged and the parents are no longer as protective.
Dive-bombing crows are using intimidation to keep what they think is a potential threat away from their young. They rarely hit their targets. If entering the crow's nesting territory is unavoidable, carrying an open umbrella will keep the protective parents from coming too close.