Intelligent and highly observant, the American crow has adapted easily to life in cities and suburbs.
Corvidae
American crows, ravens, magpies, and jays belong to the large crow family, found around the world. Medium to large in size, the corvids have strong bills and feet, large wingspans, and nostrils covered in bristle-like feathers. Male and female are much alike in appearance and size.
Mated pairs will noisily and aggressively defend a nesting territory, even attacking larger animals or humans. Corvids also mob together to chase away larger predator birds. Most corvids do not migrate, although they will move in search of food or away from very cold winters. During the winter, they often gather in large flocks to forage or share communal roosts.
Omnivorous, corvids will eat almost anything they discover while walking on the ground or branches. They hunt small mammals, nestling and small birds, amphibians, crustaceans, and insects. They also gather berries, fruit, and seeds. They are important scavengers of carrion, which has led them to associate closely with garbage dumps, animal feed, and other human-provided food sources. Corvids will also hide or cache food in multiple locations, returning months later to the correct spot. After eating, corvids clean their beaks on vegetation or dirt.
Known for their intelligence and ingenuity, corvids use tools and live in complex social groups. They are very vocal birds and, in addition to making hoarse caws or cries, alarm, and comfort calls, they mimic other animal sounds or noises. Even though people keep ravens or crows as pets, these birds are widely viewed as pests. Populations have increased, as corvids are well adapted to human activity.
(Corvus brachyrhynchos)
Intelligent and highly observant, the American crow has adapted easily to life in cities and suburbs.
American crows average 17.5 inches in length, with a 39-inch wingspan, and weigh around 1 pound. Their wings are broad, and they have a short, fan-shaped tail. There are 4 regional subspecies, which differ slightly in size and proportion. A slightly smaller relative, the Northwestern crow, is found in the coastal areas of western Canada and Alaska.
Plumage and coloration. The feathers are iridescent black, and the bill, feet, and legs are also black. Occasionally there can be some white patches on the wings.
Adaptable to most habitats, crows prefer lower elevations in wooded areas near open areas such as grassland, cropland, or shoreland. Some Canadian and American crows migrate southward, but not long distances; in most areas, however, they are full-time residents. They are often seen in small groups foraging on the ground. Although they do scavenge carrion, they are active hunters. While they will feed on crops, they also eat many insect pests.
▲ American Crow
Crows are found throughout the continental United States and southern Canada. The population is estimated at about 30 million.
Crows are monogamous and occupy the same territory each year, forming cooperative family breeding groups of up to 15 birds. The yearling offspring remain with their parents, helping to care for nestlings and defend territory. Crows prefer to nest in trees but will use shrubs or even ledges on buildings. Beginning in early April, the female lays 3 to 6 eggs. Although they mature at age 2, young birds usually do not establish their own nests until 4 to 5 years of age. The life span averages 7 to 8 years although captive birds live much longer. Raptors and owls prey on adult birds.
During the nesting season, small groups of nonbreeding birds can also form small floater flocks. When nesting is over, crows often forage in large groups of thousands of birds and share nightly roosts with additional groups.
(Corvus corax)
The raven’s large, heavy bill gives it a distinctive profile.
Ravens average 24 inches long, with a 53-inch wingspan, and weigh about 2.6 pounds. Larger than crows, they are distinguishable by a heavier, larger bill; longer and narrower wings; a long, wedge-shaped tail; and a hoarser call. Ravens have glossy black coloring with a shaggy ruff of feathers or hackles on the throat. Ravens also soar and glide more than crows do.
The smaller Chihuahuan raven is found in areas around western Texas.
Ravens are often found in hilly or mountainous forests; near open areas of grassland, deserts, and scrubland; near open seacoasts or riverbanks; and in the tundra. They are found less often in human areas than crows, although they can adapt to both agricultural and urban settings; in some areas, in fact, they have become agricultural pests. Most often living as solitary individuals or nesting pairs, ravens less commonly form foraging groups and roosting flocks, depending on food resources. They roost in large trees, cliff sides, electric towers, and manmade structures.
It is unknown whether pairs mate for life, but from late winter to early spring the female lays 3 to 7 eggs. The pair aggressively defends the eggs and nestlings from raptors, owls, and other predators. The young may leave their parents by 7 weeks of age or remain with parents somewhat longer. Mature at age 3, wild ravens live an average of 13 years, although ravens in captivity live far more than 40 years.
Ravens are primarily scavengers of mammal carcasses and the insects that populate them, approaching cautiously after vultures have torn carcasses open or crows or jays have begun to feed. Omnivorous hunters and gatherers, they will consume the afterbirth of livestock, pick through animal dung and garbage, prey on eggs and nestlings, and store or cache food.
▲ Common Raven
Ravens are found in the western states north into Canada and Alaska, and east from upper Canada to New England, including Ontario, Quebec, northern Minnesota and Wisconsin; and south into the Appalachians. Birds living in arctic areas do migrate, while most other ravens are year-round residents. As the population recovers, ravens are beginning to return to former areas in eastern and middle states, and the northern plains.
(Pica hudsonia)
Black-billed magpies build large, canopy-covered, basket-shaped nests high in trees.
The black-billed or American magpie averages 19 inches in length, with a 25-inch wingspan, but weighs only 6 ounces. Males are somewhat larger and heavier than females. This magpie has a black head and neck; white shoulders and belly; a large white area on the wings; and iridescent blue or blue-green on the body, wings, and tail. The tail is very long, forming half the length of the bird, and the feet and bill are black. The closely related yellow-billed magpie is found only in California and is distinguished by a yellow bill and a yellow streak around the eye.
Originally associated with the great bison herds, magpies are now often found in close association with cattle on rangeland, where they perform the same function, helpfully eating ticks and other insects off the animals. Magpies also scavenged the carcasses of bison hunted by Native Americans. Although preferring open areas with scattered shrubs and trees, they can also be found in pine forests, farmland, and more suburban areas. Unless frightened, magpies can be bold or nearly tame with humans.
Although they are mostly permanent residents, some birds may descend to lower elevations in colder months. Nesting territories vary in size depending on food resources. The birds form loose family flocks of 6 to 10 birds. Several hundred birds come together in social roosts in winter, perching and sleeping in individual trees.
Hunting and foraging. Walking on the ground, magpies eat primarily insects but also eggs, small hatchlings, rodents, seeds, berries, fruit, and grain. They cache food in the dirt and cover it with debris. Magpies also scavenge kills from larger predators, and pick through garbage, animal feed, and dung. They will pick at wounds on cattle or the eyes of newborns, kill nestling poultry, and eat eggs.
▲ Black-Billed Magpie
Magpies are found in the interior of the western half of North America, from southern Alaska, through western Canada, south to northern California, Arizona, and New Mexico.
Magpies are monogamous, sometimes mating for life. Breeding season runs from March to July. Pairs build an elaborate domed nest high in a tree. The female incubates 6 to 7 eggs, but within 2 months the young leave to join other juveniles. Reaching maturity at ages 1 or 2, they do not live long in the wild but in captivity will live to 20 years. Raptors, owls, crows, ravens, and many small predators prey on magpies.
The corvids eat a large variety of insect pests and are important scavengers of carrion, but they can also eat fruit, nuts, and grain crops. They are known to kill young goats, lambs, and calves by pecking at their faces and plucking out their eyes. They also attack the young of poultry, eat eggs, and peck at sores on livestock. Many members of the crow family will dive-bomb humans or other animals in defense of their nest.
The Migratory Bird Treaty Act protects crows, ravens, and magpies. It is unlawful to hunt, capture, or harass them, or take their eggs. Ravens are listed as Endangered in some states. State and local laws vary.
Young goats, lambs, calves, the young of poultry, eggs
Birds begin foraging very early in morning, and all attacks occur during day.
Because corvids are primarily scavengers, they will be attracted to dead or dying animals and birthing. This behavior can be misidentified as predation.
Crow: Classic, 21⁄2 inches long and 13⁄4 inches wide.
Raven: Classic, 33⁄4 inches long and 2 inches wide.
Black-billed magpie: Classic, 2 inches long and 11⁄2 inches wide.
Claw marks visible
Crow: Walking stride 5 inches
Raven: Walking stride 20 inches
Black-billed magpie: Walking stride 6 inches
Semiliquid, brown, black, and white, but varies with diet
