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Healthy Animals, Healthy People, Healthy Planet


Rio is a male Swainson's Hawk (Buteo swainsoni) who joined our club in the summer of 2008 from Oaksdale, WA. He has a left carpal fracture and was believed to have been shot as evidence by bullet fragments on his radiograph. We do not know his age as he came in as an adult already.
Swainson's Hawks come in different color variations. Most Swainson's Hawks are a medium to dark brown on the back of their body with a nearly white belly. This is known as the "light morph". They have white faces and a light reddish-brown to medium brown color around the front of their necks. They are very recognizeable under their wings in flight with dark (gray) flight feathers and nearly white arms. About 10% of the Swainson's Hawk population is dark, known as the "dark morph". Dark morph Swainson's Hawks have a dark brown head, back, and upperwings. They still have dark (gray) flight feathers, but have a more rufus color to their arms. Their chest is also more rufus. Though not common, some individuals can be "intermediate morph"between the two variations.
Swainson's Hawks can only be seen in Pullman during the late spring to early fall. They have one of the longest migrations of any North American raptor, migrating south to Argentina in South America.  In their summer breeding grounds (like in Pullman), Swainson's Hawks will eat small mammals, birds, and reptiles, but in their wintering grounds, they will mostly eat insects (especially grasshoppers). This makes Swainson's Hawks very susceptible to pesticides including DDT.  
Though legally banned in the United States, other countries that still use DDT and other harmful pesticides have devastated the Swainson's Hawk population. Thanks to international cooperation and interest in saving the Swainson's Hawk, the Argentinean government is now in the process of banning its use of these harmful chemicals.

Died November 2010

Washington State University