guk, you've got an interesting scenario there. For my money, I'd bet that at some point one species or the other is going to win. Depends on what happens habitat-wise. Wolves are more adapted to big woods, coyotes to fragmented habitats like fields and strips of bush. Either the wolves won't be able to sustain themselves in fragmented habitat, the coyotes will get eaten and reduced, or (and here is the scary scenario) the wolves will be reduced in numbers until they interbreed with the coyotes. This is why northern coyotes are bigger than in teh south - more genetic contact with wolves. So you end up with the flexibility and cunning of a coyote, only almost as big as a wolf (similar to coydogs - crossbred coyotes and feral dogs)
Like I said above, predation is a factor, but not the only one, and the hardest to tackle effectively.
Mortality numbers are real tricky, too. When they say coyotes kill 70% of fawns, you have to consider how many may have died anyways. When a human hunter kills a healthy, mature buck, it's a pretty good chance a coyote isn't going to kill it. But if a hunter kills a small doe or a first year spike, there's a good chance a predator would have gotten it anyway. This is why game management is a crap shoot. There's so little quality information around, the best you can go by is sightings by hunters, which aren't reliable in a statistical analysis sort of way. And no one, at least here in Ontario, has the money to do any actual studies. So it's mostly guesswork. What's killing the deer isn't the whole story - it's what's killing the deer in addition to other mortality. If coyotes were killing only healthy deer, then 70 percent is a crazy number. But if 50 percent of those deer they kill would have died in winter or from disease anyway, then the statistic starts looking less alarming.
The most bang for your buck policy is reducing doe harvests. That will work immediately, as each doe can have 2 fawns. At a certain point you get predator saturation in the population where the coyotes simply can't eat the fawns fast enough. Reducint predator populations in the scenarios listed above is a good idea too, but it's not going to have the immediate relief to a deer population like reducing does killed.
That 100 does in 5 years stat above is scary. I don't care how few coyotes you have, that's a recipe for disaster.Reduce that to 1 doe a year, and you have 95 more does in the population having fawns. As long as your sex ratio doesn't get to like 8 to 1 for does-bucks, your population will do much better (although this policy won't breed for big bucks, just for lots of deer). Then bring the doe permits up - reasonably - when the population starts to overheat again.