Thursday, July 23, 2009


Nature Watch

By Susan Benson,
CNHM Director of Education

For the past two weeks, I have been greeted daily at home by a lone crow. This is a continued surprise to me, because crows are social birds, more often observed in groups than alone. Was it injured? Looking for food? A young crow? All were questions I asked. In fact, young crows often assist their parents in raising the young for several years. One crow family can contain up to fifteen individuals with youth from as many as five combined years. In the winter they gather together in very large groups to sleep in communal roosts. Crows are considered highly intelligent animals, known for their impressive counting skills and use of tools.
Experiments with captive common, or American crows have proven the birds have excellent puzzle-solving abilities, can count up to three or four, have good memories, and can quickly learn to equate certain sounds or symbols with food. Known to eat the shells of clams, mussels, and mollusks, crows have learned they can eat more easily by picking the shells up, flying with them to a greater height, and then dropping them to rocks below. Herring gulls and crows were seen practicing this technique at the same time, but while the gulls dropped the mollusks onto the mud, crows figured out quickly that aiming for a rock worked better.

Crows have other creative ways to find food. During spring in Norway and Sweden, fishermen make holes in the ice and drop their fishing lines into the water. Hooded crows have been seen flying in, picking up the line, and walking backward, pulling the line out of the hole until they expose the bait or hooked fish to eat. Crows on a remote Pacific island have learned how to use tools. The birds use long, specially chosen twigs to spear the plump grubs that hide deep beneath the bark of rotting logs. Crows will follow adult birds to identify where the nest and eggs are located. Observers have seen crows shaping a stick to place in a hole in a fence post to search for food. They work together in groups called mobs in order to get food.
Crows have a varied and evolved language more extensive than just the “caw” with which we are familiar. They also have the danger calls and a hollow, rattle greeting sound. They can mimic the sounds made by barred owls and other bird species, and they learn to associate noises with events, especially when the events relate to food.
While some might find the results of crow’s adaptability an annoyance because of how they interact with the human world, their resourcefulness can also be highly regarded. Please share any crow observations you have made by Emailing the Museum at

For 40 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility and exhibits, the Curiosity Center and Brain Teasers 2, in Cable at 13470 County Highway M. Also find us on the web at to learn more about exhibits and programs.

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