We are used to the idea that in order to be intelligent, an animal needs a large cerebral cortex. So we can accept the idea that chimpanzees, dolphins, elephants and even humans are intelligent.
Birds do not have large cortices: instead, another part of the brain, the hyperstriatum is well developed. Crows, ravens and magpies are in a group known as the corvids.
These birds have very large hyperstriata, and their brain to body mass ratio is about the same as that of dolphins. Here are some facts about crows which the councilors in Chatham ought to think about before they send out the firing squads again:
* In Sweden, crows catch fish by using the fishing lines which humans leave in holes in the ice. The birds grab the line in their beaks, walk away from the hole, then walk back on top of the line so that it doesn’t slip back. They repeat this several times until they have brought the fish to the surface.
* Crows drop palm nuts onto highways, and wait for passing cars to crack them open.
* A crow in a laboratory in Chicago was given food, but sometimes the techniciansforgot to moisten it properly. The crow picked up a small plastic cup that had been given to him as a toy, flew across the lab and filled it up with water, which he emptied onto this food. If he spilt the water en route, he went back and refilled the cup.
* Crows in aviaries place solid objects in their drinking dishes to raise the level of the water so that they can drink it.
* Crows in cages have been seen to use sticks or strips on newspapers to rake in grain which has fallen outside the cage.
* Crows have at least five calls which refer to different kinds of danger. Their calls are not all innate: there are different dialects in different parts of the US. North American crows understand some, but not all, of the calls made by crows in Europe.
* The raven, a close relative of the crow, can match different sets of objects based on the number of objects in each set. The birds can count up to six.
* Like humans, in Germany many crows serve as apprentices. Adult birds have up to five “helpers”, who are mostly children from previous clutches. The helpers watch their parents making the new nest and finding food for the nestlings. This suggests that nest building and foraging behaviour is learnt, rather than innate.
The intelligence of crows has been known since ancient times, and they are the subject of many legends. They are often accredited with supernatural powers. For example, in Roman times, the members of the Roman College of Augurs foretold the future by listening to the croaking of crows. Unfortunately, the animals’ high intelligence has created irrational fears in some humans.
This has lead to the animals being persecuted, a phenomenon known as corvophobia. This may be what has gripped the councilors of Chatham, Ontario. If you would like to express your feelings to the person responsible for killing 30,000 crows, please e-mail Bill Erickson at [email protected].
Dr. Paul Kail is Founder of the Animal Consciousness Foundation