Bold, shy, and persistent: Variable coyote response to light and sound stimuli

To improve frightening device technology for managing predation, we examined variation in coyote (Canis latrans) response to visual, auditory, and combined stimuli using a behavior-contingent programmable frightening device. We hoped to gather information on the relative effectiveness of light, sound, and combined stimuli for deterring coyotes from a food resource. We exposed five pairs of captive coyotes each to one of three stimuli during a 10-day treatment period. Coyotes habituated to the three stimuli differentially (χ2 = 7.8, d.f. = 2, P = 0.02). Four of five coyote pairs habituated to sound treatment, one of five pairs habituated to light stimulus, and none of five pairs habituated to combined stimuli. We further examined variability in coyote response to the device and determined that social status predicted boldness; 67% (S.E. = 12%) and 33% (S.E. = 12%) of subordinate and dominant coyotes attempted to eat the protected food respectively. Similarly, 60% (S.E. = 15%) and 20% (S.E. = 18%) of subordinate and dominant coyotes habituated and ate respectively. Our findings suggest that light may be the most important component of a frightening device for coyotes, but because coyotes can be bold or persistent, significant numbers of coyotes are expected to overcome a frightening device's long-term effectiveness.