Wednesday, April 30, 2014

THE RAVEN

THE RAVEN Scientific Nomenclature (Yes, I know nomenclature can be boring, but you can learn an awful lot about an animal from its name. For example, you can learn which other animals are closely related to it, or about its shape and sometimes size, or even particular habits of the animal which influenced its naming. If you have the time, I recommend learning where your favorite birds fit in the grand scheme of things.) Kingdom: Animalia.This distinguishes animals from, say, plants. Not that you'd be likely to mistake a bird for a carrot, but you never know. Phylum: Chordata.This includes all animals which have, at some point in their development, a 'notochord' running down the length of their bodies. The spines of vertebrates put them into this category. Class: Aves.All birds are members of this class, whether they fly or not. Order: Passeriformes.Commonly called the 'songbirds', these are the 'perching' birds... the ones most people think of when they think of birds. (Very few people immediately picture an ostrich, flamingo or vulture when the term 'bird' is mentioned). They are also well known for their voices, which are loud and commonly heard. Family: Corvidae.This family includes all the 'crow' type birds, including Magpies, Jays, Nutcrackers, Ravens, and, of course, Crows. The family emerged in the middle Miocene period (23.7 - 5.3 million years ago). Genus: Corvus.This is the classification especially for ravens and crows. Within this genus are different species of both, but their scientific names all start with 'Corvus'. They got the name from the deep-throated 'croak' which is their distinctive call. Species: corax.The Common Raven (Corvus corax) is one species of raven. Another isC. cryptoleucus, also known as the Chihuahuan raven, which lives in the SW United States and Mexico. What they Look Like Ravens are large black birds, with a blue-purple iridescence to their feathers. They are approximately 24-27 inches long at maturity, and their wingspan doubles that. The beak and feet are black, and the iris of the eye is brown. Young birds are less glossy than adults, but they lose the dullness when they reach maturity. Although they are frequently confused with crows, ravens differ in many ways. A raven's beak is larger and heavier than a crow's beak. Their throat feathers are more pointed and elongated, giving them a 'spiky' appearance when they fluff up. Crows' throat feathers, on the other hand, are rounded, like a semicircular fan. Most noticeably, their caw is much deeper than the crow's call, and much throatier. Also, a raven's call is more varied than the repetitive cawing of a crow. Click herefor more detailed information about the way crows and ravens differ. Range Ravens are a common sight in countries around the globe, and can survive in many different climates. They range from islands in the northern Arctic to deserts of North Africa, from the Pacific to the Atlantic Coasts of North America. They can be found in England, in Mexico, in Turkey, and many other locations. Preferences vary with species, but most prefer wooded areas, especially along the coast and in the mountains. An individual raven, or a nesting pair, will pick a territory around the nest which in which they forage for food. While it is flying within its territory, the raven is a friendly, unsuspicious bird. It is known to frequent human dwellings and farmsteads where it knows food will be left out for it. When it is nesting, however, the raven is wary and secretive. Nesting Habits Ravens nest in single pairs (pairs which stay away from other nesting pairs). Evidence suggests that, once paired, ravens will remain mated for life. They build their nests on cliff ledges and cavities, or in trees. The nest is a mass of sticks and twigs, lined with grass and bark, and often with bits of string or other tidbits which caught the builder's eye. Within that nest, the female raven will lay 4 - 7 eggs, which are greenish, blotched with brown. Both parents incubate the eggs, and feed the hungry young. Young stay in the nest for approximately 6 - 10 weeks. Eating Habits Ravens are omnivorous. They will eat anything which is edible (and many things which aren't). Their usual diet contains insects, seeds, berries, carrion (the bodies of animals killed by creatures other than the raven), the eggs and young of other birds, and occasionally small mammals. When living near humans, ravens will also eat human garbage. Legend has it that a raven's favorite food is the body of a dead man, or of other dead animals, and that a raven will go first for the eyes of such a fallen creature. Other tales say that ravens will hunt with wolves and share the kill with them. There may be a certain amount of truth in these, for ravens do have a certain fondness for eating flesh. Dead bodies, however, take some time to decompose before the birds can easily tear the meat from the carcass. By going for softer tissues, like eyes, the birds are more likely to get a quick meal. Also, by following a hunting pack of wolves, ravens will have access to the meat as soon as the wolves begin to tear up their kill. Despite their morbid tastes, ravens also do mankind a favor, by eating a number of undesirable insects, and sometimes even noxious weeds. Miscellaneous Information Ravens have been associated by various cultures with different qualities. In popular western literature, they symbolize darkness, depression, and death (popularized in Edgar Allan Poe's poem, 'The Raven'). In medieval times they stood for virility. Among native cultures, Raven is the 'trickster' spirit, a popular totem, and the creator of man, who placed the Sun in the sky. Back to the Aviary Send mail to The Raven Credits & References This document does not claim to be completely accurate or scientific. It was compiled from personal experience, discussions with biology teachers when I was in high school, and the following sources: The Canadian Encyclopedia, 2nd Ed.(1988) vol. I-IV. Hurtig Publishers, Edmonton. The Birds of Alberta, 2nd Ed., W. R. Salt & A. L. Wilk (1966). The Queen's Printer, Edmonton.