Or bears..
@Wangobango3 They sure did in Kentucky. I had five dogs, put kept them in two fenced dog yards by the house when they weren't with me, to prevent them chasing wildlife and birds. They always went with me when I rode my gaited horses over the hill trails, yet I frequently encountered bears in the blackberry thickets.
We just ignored each other, but if bears came around the horse pasture at night, they'd freak out.