Mule Deer Doe Pursuing Golden Eagle Circling Her Fawn at Low Elevation. 12 June 2009 Jorma Jyrkkanen

Observation of an adult female mule deer (Odocoilius hemionis hemionis) pursuing a Golden eagle (Aquila chrysaetos). 12 June 2009

While inspecting for range fires I observed a Golden eagle take off from the ground and in hot pursuit was a female Mule deer doe. The eagle did broad low loops over the area trying to gain altitude in dead air and the mule deer ran flat out after it. When the eagle landed in a tree she ran right up to the tree and looked up at it. I have never seen a mule deer run as fast as her before. Fawns are quite small in the first week or two of life in this area and are thus subject to predation by golden eagles, coyotes, bears and cougars. This doe acted as if she were very angry at the eagle and perhaps she had lost a fawn to one already or she was protecting a fawn concealed on the ground. I went to the area where she came to rest after the eagle had left but could find no fawn. She was slim as if she had already given birth. I have had a caribou female with calf at heel stand up on her hind feet and paw towards our chopper in the McKenzie basin NWTT when our helicopter approached her perhaps too closely. Some of the accentuated behavioral response of ungulates to eagles is no doubt a honed remnant of the days when huge thunderbirds roamed the skies before the Pleistocene extinctions although eagles are able to take animals as large as gazelles and so this observation is quite within the range of normal ungulate anti-predation behavior. Tags: golden eagle, jyrkkanen, mule deer, predation, reaction