Crows and ravens are intelligent. They are known to be smarter than dolphins, chimpanzees and Congress. For one thing, they can work together to solve problems, unlike Congress. We don’t know which are cleverer — crows or ravens — because in a chess match both insist on playing black.
Crows and ravens can be difficult to tell apart. The common raven is larger than the American crow, weighing twice as much. Crows average 17-20 inches in length; ravens 27 inches or more. Crows are barely larger than pigeons. Ravens are the size of red-tailed hawks. If they would simply stand next to each other in the field, the size difference would be obvious, but they are seldom that obliging. Furthermore, ravens seem to be remarkably uniform in size, while crow size varies. There are some big crows out there and they fool me sometimes. In self-defense, I’ve learned to look for additional clues.
For a sitting bird, bill size is the easy clue. Both have heavy bills, but the crow’s bill is more slender and pointed. A raven’s bill is enormous. I exaggerate when I claim it to be the size of a banana, but that description doesn’t miss the mark by much. Not only is the raven bill longer, it’s thicker. The top of the bill extends from the top of the forehead, giving its bill a bulky, almost rectangular shape. The big bill and longer neck even help to identify a flying bird. A soaring raven appears to be as long in front of the wings as it is behind.
Size does matter, but the eye can be fooled by distance and lighting. It is difficult to judge the size of a flying bird against a background sky. A bird beating upwind appears smaller than one gliding downwind. We need more clues. The tail is the dead giveaway when the bird is overhead. The tail of a flying raven is long and diamond-shaped. Middle tail feathers are longer than the outer feathers. The tail of a crow is shorter, with tail feathers of even length. Wing shape is different, too. The wings of a raven are proportionally much longer, with lengthy primaries sticking out straight, like open fingers. Crow wingtips sweep backwards, like closed fingers.
Wing shape yields two more subtle clues. Because the raven’s wings are much longer, its wingtips often appear to tilt up while flapping, and its wings appear to beat effortlessly up and down. With their shorter wings, crows fly with a faster, rowing motion, their downbeats churning backwards. Observing these subtleties requires practice, but since these birds are around all winter, you’ve got plenty of time to observe and no distraction from songbirds.
Thanks to all these clues, an overhead bird is not terribly difficult to ID. Naturally, in their continued efforts to frustrate you, they are seldom overhead. You usually see them flying toward you, or away from you, or to the side — all angles that obscure their field marks. Fortunately, they also behave differently.
Crows form flocks. Ravens don’t. A family of ravens may stick together for a while, but there are seldom more than four ravens together.
Ravens soar. Crows don’t. If a bird glides for more than a couple of seconds, it’s a raven. Ravens are much more acrobatic. They can somersault, cartwheel and fly upside down. It even appears that they do it for fun. In strong winds, I’ve watched ravens fly at a cliff face, catch the sudden updraft and go “wheeeee” as they barrel roll skyward, doing it over and over.
Here’s a behavior I see a lot, and I can’t explain it. Ravens often fly along a road. Crows fly across it. When I am driving and see a bird flying along the road towards me or away, it invariably turns out to be a raven.
Crows caw. Ravens croak. Both have a variety of vocalizations, but ravens generally sound more guttural. Their voices carry long distances. On a beautiful winter day with winds that favor soaring, my attention is often drawn to ravens that are flying much higher than would be typical of crows. In June, when the young are fledgling, ravens give out a blood-curdling shriek that serves to keep the family together. Ravens in captivity can even learn to mimic human words.
There are plenty of clues: size, bill, tail, wing shape, flight patterns, unusual behavior. With all these hints, will you have trouble identifying a raven in the future? Nevermore.
Bob Duchesne serves as a Maine Audubon trustee and vice president of its Penobscot Valley Chapter. Bob developed the Maine Birding Trail, with information at mainebirdingtrail.com. Bob can be reached at duchesne@midmaine.com.