The monastery where I spent the weekend is a working sheep farm. Benedictine monasteries are self-supporting, and raising sheep is an important part of their income. So a few years back, when coyotes started picking off baby sheep, the monks were alarmed. Brother Tractor consulted the DEC, who offered to send in sharpshooters to kill off the coyotes.
Brother Tractor said, "That's not really in keeping with our monastic ways."
Instead the monks bought a couple of donkeys. The donkeys wander the pastures with the sheep, occasionally stopping to bray, which apparently scares away the coyotes.
Last weekend, while I was standing in the sheep barn, watching the ewes and baby sheep, a donkey came up behind me and brayed loudly. I jumped about a foot. I can see how that noise would keep away predators.