Wednesday, July 17, 2013

Common Raven

Common Raven - Corvus corax








Ravens are intelligent. In one experiment a Raven was presented with some meat hanging from a long string tied to a high perch. There was no convenient place to access and eat the meat. The Raven solved the problem by lifting the string onto the perch, placing a foot on the string to hold it in place, then lifting more string, and again securing the string under the other foot, and then repeating this process until the meat was pulled up to the perch and accessible to eat.


In non-verbal experiments, Ravens have been shown to "count." The Ravens in the experiment recognized groups of different sizes up to a total of seven.
Juvenile Ravens that come across a carcass in winter recruit other juveniles to share in the food. This altruistic behaviour is thought to be necessary to secure the food source from the resident adult Raven in the neighbourhood. 

References

The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.

Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.

Beadle D, Rising J. Sparrows of the United States and Canada. Princeton UP. 2003.

Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.


Sibley David A. The Sibley Guide to Bird Life and Behavior. Alfred A Knopf, Inc. New York. 2001.

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