I used to have chickens, but they never ate the snails. They used to eat the sowbugs, though, so that was cute and useful. What wasn't cute was their habit of digging up and pulling out all of the little bedding plants as soon as I planted them. They would walk up and down the front of a border and pull out every single baby aquilegia plant.
I've never heard of predator snails. Diatomaceous earth might work, but I have half an acre of plants that attract snails. Any solution is going to be costly. For now, I just apply snail bait weekly and avoid the plants that are particularly appealing to snails.
