As of 2003, the IUCN lists seven owl species as Critically Endangered, facing an extremely high risk of extinction, or dying out, in the wild; nine species as Endangered, facing a very high risk of extinction in the wild; and eleven species as Vulnerable, facing a high risk of extinction in the wild. A number of owl species occur on only one small island or in one small area. That makes these species particularly vulnerable to extinction.
In the United States two owl species are protected under the Endangered Species Act. The ferruginous pygmy-owl is listed as Endangered and the spotted owl is listed as Threatened.
Habitat loss because of logging or agriculture is the biggest problem for owls. Other causes of mortality include illegal shooting, collisions with cars and human-built structures, electrocution on power lines, and poisons used against rats and mice.
FOR MORE INFORMATION
BirdLife International. Threatened Birds of the World. Barcelona and Cambridge, U.K.: Lynx Edicions, 2000.
Duncan, James R. Owls of the World: Their Lives, Behavior and Survival. Buffalo, NY: Firefly Books, 2003.
Johnsgard, Paul A. North American Owls: Biology and Natural History. Washington, DC: Smithsonian Institution Press, 2002.
Kaufman, Kenn. Lives of North American Birds. New York: Houghton Mifflin Company, 1996.
König, Claus, Friedhelm Weick, and Jan-Hendrik Becking. Owls: A Guide to the Owls of the World. New Haven, CT: Yale University Press, 2002.
Lewis, Deane P. The Owl Pages. http://www.owlpages.com (accessed on June 25, 2004).