The Common Raven (Corvus corax) is a large black bird in the crow family. Its feathers are iridescent and the bill is large and slightly curved. At maturity, it is between 24 to 27 inches (60 to 78 cm) in length, with a wingspan twice that.
Apart from its greater size, the Raven differs from its cousins the crows by having a larger and heavier beak, and a deeper and more varied barking prrrukk call note. Other field points are the shaggy throat feathers and a longer, wedge-shaped tail.
Ravens thrive in many climates. Their range extends from the Arctic to the deserts of North Africa, and to islands in the Pacific Ocean; the largest range of any member of the genus. Most ravens prefer wooded areas (with large, open land nearby) or coastal regions for their nesting sites and feeding grounds. In some areas where there is a large human population, such as California in the United States, ravens take advantage of an enlarged food supply and have seen a surge in population. In other areas, such as parts of Europe and the eastern United States, raven populations have been greatly reduced due to human intervention.
Much of the raven’s behavior is believed to be related to mating and reproduction. Juveniles begin to court at a very early age but may not bond with another bird for at least 2-3 years. Aerial acrobatics and displays of intelligence along with its ability to provide food are key behaviors of courting ravens. Ravens tend to be monogamous for life, and usually nest in the same location each year. The pair will build their nest on cliff ledges or in tall trees (or building ledges in larger cities). Breeding pairs must have a territory of their own before they can begin nest-building and reproduction. This territory and its food resources are fiercely defended against others. The nest is made of large sticks and twigs lined with a softer material, such as deer fur. The female lays 3-7 pale bluish-green, brown-blotched eggs and both parents take turns incubating and feeding the chicks. As with many birds, pairing does not necessarily mandate sexual monogamy, and raven habits show fluidity in this regard.
Ravens have a varied diet including insects, berries, fruit, other birds’ eggs, carrion, wolf or dog feces, and human-produced foods such as bread. They occasionally will kill small birds and mammals, including young rabbits and rats, but do so mainly as opportunists. Popular beliefs about ravens include the notion that they are attracted to shiny objects, but research indicates that juveniles are deeply curious about all new things, and that ravens retain an attraction to bright, round objects based on their similarity to bird eggs. Mature ravens lose their intense interest in the unusual, and become highly neophobic, taking up to three days to begin feeding on dead mammals.
Ravens have impressed biologists with their apparent intelligence and insight. Experiments have shown that members of the crow family are capable of using tools; an experiment, where some desirable item lay on the bottom of a bottle, showed that some of these birds were able to form a hook to reach the item. Like other crows, ravens can copy sounds from their environment, including human speech to a certain extent. They have a wide range of vocalizations, which remains an object of interest to ornithologists.
The Common Raven is the official bird of the Yukon.
Many large black birds of the genus Corvus are also called ravens. Other birds in the same genus are the smaller crows, jackdaws, and Rook.
Other raven species include:
- Australian Raven (C. coronoides)
- Forest Raven (C. tasmanicus)
- Little Raven (C. mellori)
- Thick-billed Raven (C. crassirostris)
- White-necked Raven (C. albicollis)
- Brown-necked Raven (C. ruficollis)
- Chihuahuan Raven (C. cryptoleucos)