Cubbysan, I am so sorry for your loss. My first thought on reading it was fox but I agree with Trish that a coyote is also a possibility - I don't know a lot about their modus operandi. We supposedly get them around here but I've never seen one. I don't know if fisher cats are in this area or not - I know nothing about them except the name. I had a fox visit last July and it climbed a 5' fence made of 2x4 welded wire, like it was a ladder. Somehow I didn't expect that. I thought predators would dig under before they'd try to climb over, but I watched it do it. The destruction you described does sound like a bigger animal. Possums and raccoons tend to eat a specific part in place versus carrying it off. With my fox attack, I lost 14 birds in the first visit but only had 13 bodies - the 14th was gone, gone, gone. I believe he planned to come back for the others but I interrupted him. The second visit I lost two more birds and again, one of them I never saw again. I left the second out for him as bait and sure enough, he came back for it and that was when I had a chance to stop him for good.
Unfortunately I don't know what to tell you about prevention. Whatever predator it is, it will probably be back until it is eliminated, as once they have found a food source, they will return again and again. I was fortunate that mine was probably young and inexperienced, and I only had to wait 20-30 minutes that second day for him to come back, and then I was able to eliminate him for good, but if you have one that is not visiting daily, it will be harder to catch. Foxes are very.....sly.
Your best bet is to bolster the coop and run, using materials it can't tear holes in, and not let them out to free-range for awhile. Hopefully once it finds out there is no more free food available, it will move on.