Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)



Committee Chair(s)

Michael R. Conover


Michael R. Conover


John A. Bissonette


Frederick F. Knowlton


Lyle G. McNeal


Robert H. Schmidt


To evaluate preventive aerial coyote hunting as a depredation management technique, I compared sheep losses to coyote (Canis latransl predation and the hours of corrective predation management required on summer grazing areas with and without hunting the prior winter from helicopters. Correlations were used to test for relationships between the extent, intensity, and timing of aerial hunting and lamb losses to coyote predation. Data on the age, sex, and reproductive status of coyotes killed using aerial hunting, traps, snares, and calling-and-shooting were used to test for differential coyote vulnerability to damage management tools, and to assess the impact of aerial hunting on coyote populations.

Winter aerial hunting reduced confirmed and estimated lamb losses to coyote predation and the hours of effort required for corrective predation management the subsequent summer. Aerial hunting increased the number of coyotes killed annually per grazing area, but did not reduce summer coyote removal. There were no consistent relationships between the extent, intensity, or timing of aerial hunting and sheep losses to coyote predation. The male: female ratio for coyotes captured with calling-and-shooting was higher than that for traps or aerial hunting. More juvenile coyotes were killed with aerial hunting than with traps or shooting. However, there was no difference in the age of adult coyotes {>1.5 years old) removed using any control method or between the age of coyotes from areas with and without consistent aerial hunting. Confounding factors in the data and the high number of uncontrolled variables prohibited clear identification of the mechanism making aerial hunting effective.

I also examined financial compensation programs as an alternative to lethal control. Nineteen states and 7 Canadian provinces had compensation programs. Compensation programs appeared to be established when wildlife problems were of recent origin, resulted from government actions, and/or were caused by highly valued species. Compensation programs for coyote damage had been established in 4 states/provinces in eastern North America where coyotes are a new problem, but are unlikely to be a acceptable tool for the western U.S.



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