Saturday, June 01, 2013

Great Blue Heron

Great Blue Heron - Ardea herodias

A Great Blue Heron standing in a marsh looks like a study in lethargy but the bird is constantly vigilant and in a flash the motionless bird can strike out with precision to impale prey that comes into range. 
This silhouette photo shows off the very sharp bill, which is used to impale fish, frogs, snakes, and smaller birds.

Although these herons mostly feed by water, the birds also feed in dry agricultural fields, presumably for small rodents and insects. 

The esophagus and trachea cross over in the neck to a position behind the vertebrae in the lower neck, presumably to enable protection for these important structures from impact injury during a strike to skewer prey. 

Great Blue Herons have a serrated talon that is used in preening.

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.

Tudge Colin. The Bird. Crown Publishers. New York. 2008.

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