I've done a significant amount of research on coyotes, primarily because I love hunting them, but through my research, I've found that "thinning out" coyotes is nearly impossible. I'll explain.

Coyotes (as well as mosquitos)have the natural ability toadjust their litter sizes to reach carrying capacity, unlike most animals (deer, elk, antelope, etc.) that generally have 1 or 2 babies per year.

For easy numbers, let's say that an area has a carrying capacity of 60 coyotes and that 25% of those (15)die each year from a combination of disease, hunters, vehicles, and old age. That means that 15 pups are are raised to maturity (more are born) each year in order to maintain the carrying capacity. In an area like this, it's probably that less than half the females breed each year. So, let's say that through intense "hunting control" that an additional 15 coyotes are killed in a year, meaning that 1/2 of the population is eliminated. Coyotes will respond to this in two ways; First, more females will breed and therefore increase the population. Second, their litter sizes will increase from say 2-3 pups to 4-6. This will occurr naturally and boost the population.

I'm not saying that the population is at 100% of the carrying capacity in every area, but the same holds true.

I recall one study that was done somewhere in Arizona (I believe). It was a population that was fairly low and not much was done to control it. They studied the females and realized that roughly 1/3 of them were breeding each year. After the breeding season took place, serious control measures were taken and the fall population was decreased significantly. The next spring, they found that almost 90% of the females were breeding and that their litters were nearly double what they had been the year before.

So, controlling the population of coyotes is very difficult. And their threat to the deer herd is exaggerated by a lot of people. Mice and other rodents make up the large majority of coyote diets. Granted, they'll take a deer if they have the chance, but they realize it's much easier to catch mice and rabbits than a deer. And like any animal, they'll generally eat what is the easiest to find. This definitely holds true during the winter in colder climates, where expending large amounts of energy on chasing deer is more detrimental than helpful.