Facts About Crows

Facts About Crows

Crows and ravens belong in the Corvid family (which includes jays and magpies) and are considered to be among the most adaptable and intelligent birds. Its coal-black coloring, highly social behavior, and distinct call make the American crow (Corvus brachyrhynchos), also known as the common crow, one of the most frequently seen and heard birds. Although most bird books recognize populations along the coast and around the Puget Sound to be a distinct species called the Northwestern crow (Corvus caurinus), some experts classify the smaller Northwestern crow as a subspecies of the American crow.

Food and Feeding Habits

Crows are omnivorous and eat whatever is available insects, spiders, snails, fish, snakes, eggs, nestling birds, cultivated fruits, nuts, and vegetables. They also scavenge dead animals and garbage.

Crows are known to drop hard shelled nuts onto a street, and then wait for passing automobiles to crack them. Similarly, along the coast they drop mussels and other shellfish on rocks to crack the shells and expose the flesh.

Outside of the breeding season, crows travel as far as 40 miles each day from evening roost sites to daytime feeding areas.

Crows usually post “sentries,” who alert the feeding birds of danger.Nest Sites and Shelter

Nests are built 15 to 60 feet above ground in tall coniferous or deciduous trees. Nests are 1½ to 2 feet in diameter, and solidly built in the crotch of a limb or near the tree trunk.

In areas that lack tall trees, nests may be placed lower in hedgerows or shrubbery. In urban areas, crows may nest on window ledges or the sides of buildings.

Nests are constructed from branches and twigs, and are lined with bark, plant fibers, mosses, hair, twine, cloth, and other soft material.

Hawks and owls inhabit old crow nests; raccoons and tree squirrels use them as summer napping platforms.

Reproduction and Family Structure

Both sexes build the nest during a period of 8 to 14 days beginning as early as mid-March and as late as mid-July depending on latitude and elevation.

The female incubates four to five eggs for 18 days, at times being fed by her mate or sometimes by offspring from the previous year.

The chicks grow quickly and are out of the nest at around four weeks after hatching, although they continue being fed by the adults for about another 30 days.

Frequently, one or more young crows remain with the  parents through the next nesting season, or several nesting

This cooperative behavior during breeding includes bringing food to the nest and guarding the nestlings.

In spring and summer, crows are usually seen in family groups of two to eight birds. During late summer, fall, and winter, crows gather from many miles to form communal night roosts.

Mortality and Longevity

Adult crows have few predators eagles, hawks, owls, and human hunters with humans being their main predator.

The causes of death of young crows still in the nest include starvation, adverse weather, and attacks by raccoons, great horned owls, and other animals.

Mortality in the first year is about 50 percent, but adults live six to ten years.

Dive-Bombing Crows
Most aggressive behavior from birds is motivated by defense of their territory or young, or their search for handouts. Hummingbirds have been noted to buzz people wearing red, perhaps thinking that they were a group of nectar-rich flowers. Pigeons and swallows may appear to be attacking humans when actually they are returning to their nests in the eaves of buildings.

In the spring and summer crows and other birds establish territories, build nests, and rear young. During this period, adult birds may engage in belligerent behavior, such as attacking creatures many times their size. In this case, the birds are simply trying to protect their homes, their mates, or their young.

When possible, stay away from nesting areas with aggressive birds until the young are flying (three to four weeks after eggs hatch) and the parents are no longer so protective. Do not attempt to “rescue” chicks found outside nests when adult birds are calling loudly nearby. If you must walk past a nest,  wave your arms slowly overhead to keep the birds at a distance. Other protective actions include wearing a hat or helmet, or carrying an umbrella.