Hard to imagine critters in BIBE!
Actually, in thirty years I have never had a serious problem with food. The advice so far is all good.
Do not leave food in your tent or pack. The likeliest problem is rodents chewing through the fabric of your equipment. On a winter trip there is little concern regarding insects, but do make sure you don't set your food on top of an ant den!
The mouse in the above pic is about to eat a glob of chocolate covered macadamia nuts. I had mostly heat-resistant food on that trip, but it did get warm enough to totally melt that one bag. I set it on a rock, away from the rest of our commissary stash, and strangely enough, it was the only thing that got touched by animals at all.
Another issue is clean up. Most animal problems develop because of what is left behind. When we carelessly slop extra food, etc. around camp, good camping areas become havens for human-habituated small animals.
If you must dispose of extra food, treat it just like human waste. Bury it a long distance from good camping, trails and water supplies. It is a good idea, even when rinsing out a cup or dish you have used to discard the water far from your camp site, preferably someplace no one else would want to camp or sit down for lunch.
Designated campsites always seem to have permanent residents who live on detritus of sloppy camper's food.
Wildlife that is truly wild is one of the treasures of our ever-decreasing true wilderness areas.
