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The acrobatic aerial display of two jet black birds soaring, wheeling and tumbling with wingtips touching --- inverted commas in the sky. This spring scene is the mating display of the Common Raven, the largest of the passerines (perching birds) that has “become the most widely naturally disturbed bird in the world, inhabiting the same continents as humans and at home in as many diverse habitats.”

How does one distinguish the American Crow from the Common Raven? In flight, the raven has a wedged-shaped tail, whereas the crow’s tail is slightly rounded. Ravens are more slender with long, narrower wings and longer, thinner fingers at the wingtips. If perched, the larger, heavier beak and thick neck with shaggy, spiky throat feathers when they fluff them up are good raven indicators.

Common Ravens are not as social as crows; you tend to see them in pairs or alone except at food sources like landfills or road kills. They prefer to live in open and forest habitats across western and northern North America. Their nests are a mass of sticks and twigs that they will use for several years, built on cliff ledges and cavities or in trees. Ravens nest in single pairs, and evidence indicates that they will remain mated for life.

Ravens do well around people, especially in rural environments but also in some towns and cities. For centuries, they accompanied people on the move, following their wagons, sleds, sleighs and hunting parties in hopes of a quick meal. What do they eat? Anything that is edible and many things that aren’t. They take advantage of any available food source. My mother lived several blocks from two fast food restaurants. Daily, she had to clean her bird bath, as a raven was in the habit of washing his French fries and taco bits there before consumption. Or perhaps he was caching them for a late night snack. Ravens are carrion eaters. Another useful behavioral clue to identification is that ravens cruise roads looking for road kill; crows normally don’t do this. Like the other members of the Corvid family (jays, magpies and crows), they store extra food, mostly burying it in the ground or hiding it in trees.

Native American mythology often includes the raven. He is a cultural hero, a trickster or the principal creator figure in many cultures, from the Tlingit of southern to Inuit of northern Alaska. The prominence of the raven in these mythologies may correlate with its purported intelligence.

Recent experiments conducted by Bernd Heinrich and Thomas Bugnyar show that these birds use logic to solve problems and that some of their abilities approach or even surpass those of the great apes. One of the experiments showed true insight when solving problems. Ravens faced with a novel task, such as getting food that is dangling on the end of a string, were able to assess the problem and then use their feet to hold the string and pull the food up. Grownup birds would examine the situation for minutes on end and then perform a multistep procedure on their first try in as little as 30 seconds. Year-old birds required at least six minutes to solve the puzzle, during which they overtly tested possibilities. Young birds (a month or two past fledging) were unable to perform this behavior, so apparently their problem solving abilities increase with age; mature ravens have the ability to test actions in their minds and project the outcomes of those actions. Wow!

If you are interested in other experiments testing the intelligence of the Common Raven, see the April 2007 Scientific American.