That is different from my experience. In my compost pile, I regularly see bluejays, ravens, and crows. Last summer I had moles in an almost finished pile, probably looking for worms. And I know I have nocturnal visitors from the evidence they leave: a bent wire fence, footprints in the snow, evidence of a bit of digging, or a tuft of fur left on the fence. (Edited to add photo.)

IME the deer, chipmunks, turkey, and squirrels aren't interested in what's in the pile because the food is wrong for what they like, but scavengers are. In winter when the snow is deep, I don't see visitors other than birds, I think because most animals stay in a smaller home area when moving through snow makes them use up too much energy. But when deep snow isn't an issue, I've seen evidence of the coyotes, fox (one summer when she was raising kits nearby), and one memorable time I hope not to have repeated, a bear left fur on a very squashed fence. In city areas I know rats can sometimes be an issue, but they haven't been in my rural area.

So some of your critters probably have other foods they prefer, but I don't know why your pile is undisturbed in times without deep snow.

Thanks for sharing the experience.

Just yesterday I saw a coyote walking across my backyard through the ankle-deep snow. It did not even sniff on the compost pile. So these animals are well-fed in winter, and do not care about compost.