Many people know that crows are intelligent creatures and that a flock of crows is called a murder. But what's the story with ravens? And how do you tell the difference between the two species?
Both the American Crow (Corvus brachyrhynchos) and the Common Raven (Corvus corax) are familiar sights on the Central Coast. Despite their croaking tones, they are considered songbirds due to their ability to master many different sounds. Ornithologists distinguish different species of crows and ravens by their voices. Crows emit a strong harsh caw, while ravens push the head forward, fluffing the throat feathers, producing a much deeper, longer croak.
The shaggy ruff of feathers at the throat is an identifying feature of ravens. They are also quite a bit larger than crows. Weighing between 1 1/2 and 4 1/2 pounds, ravens are the world's largest perching birds.
In flight, crows and ravens are distinctive. The crow has a square or rounded tail and flaps steadily when flying. The raven’s tail is diamond-shaped. It glides more often than a crow and has longer, narrower wings.
While ravens tend to be solitary, crows gather in large groups to roost at night. Roosting together in large groups deters predators like owls and hawks, which are more of a threat to the young than full-grown adults.
Crows and ravens are omnivorous, eating insects, amphibians, reptiles, birds, small mammals, human garbage, and carrion. They will follow people and other birds to find food. Along with vultures, they are nature’s cleanup crew. We've observed them sharing dead rodents with the neighborhood turkey vultures with few ruffled feathers.
Ravens and crows, along with magpies and jays hold "funerals" for their dead. When they see a fallen comrade, they begin urgent calls to alert others, gathering around the dead and scolding loudly. Scientists suspect this behavior helps them to determine what happened and if there's a threat to the flock.
Crows have amazing brains, reasoning at the level of a 7-year-old human. John Marzluff, a professor of wildlife science at the University of Washington, caught and tagged crows, wearing a caveman mask. To this day, when Marzluff wears that mask and walks on campus, crows scream at him. Some of the birds weren’t even alive when he did the tagging. “They have to spread that information culturally by social learning,” Marzluff says. “To learn from one another, to take things at face value like that, that isn’t something that happens with all species.”
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