They are known as pesks for their constant raucous cawing, their tendency
to plague farmers' fields, and their mischievous play. Despite their bad
reputation, crows have won a curious place in the hearts of many.
You're welcome to jump ahead to the area you're interested in, or skim this document for the following information:
(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: brachyrhynchos . This is the common crow, or the American Crow. Many other species of crow also exist.
What they Look Like
Crows are generally black, with black beaks and legs, but they can also be black with white, gray, or brown coloring. The common crow (Corvus brachyrhynchos) is approximately 20 - 30 cm long, with a wingspan double that.
Crows range all over North America, and some species or another can be found just about anywhere. They thrive in mountains, woodlands, across plains and farmers' fields, and throughout urban areas.
While they are raising their young, crows are not very gregarious creatures. However, they are migratory, and will assemble in large flocks in the fall, to travel south.
Crows nests are bulky structures built in trees or bushes. They are made of twigs, lined with bark, grasses, and rootlets.
The female crow lays 4-7 eggs in the nest, and the male helps incubate them. These eggs are greenish or bluish, and blotched with brown. Once hatched, the young remain in the nest 6 - 8 weeks, and in their early life they eat almost half of their weight per day in food, which the parents bring to them.
Crows are omnivorous - they will eat anything edible, and many things which aren't. Their regular diet includes animal and vegetable matter, insects, crops (especially corn), and occasionally the eggs or young of other birds.
Despite their bad reputation for eating crops, crows also eat a number of pests which are harmful to those same crops, including cutworms, wireworms, grasshoppers and even noxious weeds.
In some areas, crows are regularly shot for despoiling farmers' fields. Scarecrows, cats, and many other tactics have been used to keep them away, but they are intelligent birds and can quickly outwit most traps. Any scarecrow which remains in the same place for several days quickly becomes a perch, rather than a warning sign.
Perhaps the most famous crows are the comedic pair 'Heckel & Jeckyl', popularized in Saturday morning cartoons. The mischievous antics of these two closely capture the infuriating but humorous nature of real crows.
Credits & References
This document does not claim to be scientific or completely accurate. 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.
The Animal Diversity Web