bowbrown: welcome to the D&DH forums.
Dan's thoughts pretty well sum up the facts, and Goose's build on them.
In NE Ohio, you're not that far from me. When coyotes first started becoming common on Pennsylvania (they've been here for at least 70 years, and I can prove it), most people said they would have no effect on deer. They'd go on to describe how deer can fight them off with their antlers and hooves, and outrun coyotes. That whole argument misses the point -- it's not adult deer that are under the greatest threat from coyotes.
I've found coyote dens with deer bones around them, and photographic evidence has documented adult coyotes bringing fawns back to the den. So, I would agree that the biggest effect coyotes have on deer is during the fawning season. It stands to reason because right at the time the fawns drop, coyote pups are transitioning from milk to meat. There is also winter kill to be considered, but that is negligible.
My thinking is this: if you and I can find fawns in the woods when we spend a few hours a week in the woods, they coyotes can find them more easily, spending 24/7 in the woods. However, don't place all the blame on coyotes. Black bears also take a share of fawns, though maybe their effect on the fawn crop is not as big since the population of bears is not as dense as coyotes. While I didn't see the poo sample you found, it's not impossible that it was from a bear.
Coyotes are very prolific and adaptable, and when you remove them you're simply opening space in the habitat for another one to move into, whether that comes from a dispersing animal, or through reproduction. So, the best time to remove coyotes from the population is right before fawning season.
When the Everyday Hunter
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