If I can recall some of my game management classes, coyotes are adaptable to the quantity and quality of their prey species. They can increase litter sizes if the carry capacity of their territory dictates a healthy population. Like many predators, coyotes are very mobile and will search out higher density of prey species. Late winter die-offs of deer will send coyotes search for new territories. They also can supplement their diet with smaller prey such as rabbits and other small mammals.
Anecdotally, a dead 'yote on a fence post may allow you to feel good, its not all that important considering the big picture.
