Wednesday, September 30, 2009

Crow Bird

The crow bird belongs to the Family Corvidae which includes jays, crows and ravens. Generallymembers of this family are noisy, gregarious birds who successfully steal food from much larger animals. The crow bird is a very common black bird. It can be found all over the world, and adapts well to a variety of habitats.

The common crow bird ( Corvus brachyrhynchos) is approximately 40 cm (about 17 inches) long at maturity. It is about the size of a large pigeon. Its wingspan is around 40 inches. It is black allover. Some may have grey or white shoulders and backs. Its call is nasal �caw!� It lays 4-7 eggs which are greenish blue and marked with brown. It is found throughout most of North America.

Fish crows (Corvus ossifragus) are a rather small species of crow birds endemic to the Southeastern United States. Typically they have been restricted to the coastline from southern New England to Texas, but in the last few decades have been expanding their range, especially their range, especially inland up large rivers. They are typically found along river systems and near large bodies of water. The calls of Fish crow and common crow are readily told apart. Common crow birds most frequently give the familiar �caw caw�. Fish Crows have a much more nasal call that may be better enumerated �awh� or �uhn�. The most diagnostic call of the Fish Crow is the double noted �uh-uh�.

The Carrion Crow (Corvus coron) is a black crow bird, about 18-19� long. It has neatly feathered thighs, and feathers around the base of the beak. While at first appearance its plumage is black, on closer inspection it has a green and purple iridescence. It has many calls, but the most common is �kraa-kraa-kraa�. It has a diverse diet: worms, insects, fruit, seeds, kitchen scraps, eggs, and young birds. A Carrion crow�s nest is built in the fork of a tree and is a large construction of twigs lined with hair and bark. It is built by both birds. The eggs are about 43mm by 30mm, smooth and glossy, pale bluish-green with dark brown and grey markings. The duties of incubating the eggs are performed by the female. Both adults feed the young birds.

In general crow birds are great mimics and can learn a great variety of sounds including talking. Even between each other they use a wide variety of low calls, often sounding like they are talking to one another, human style! Although crows are familiar birds, few people are aware of the complicated lives the crow bird leads.