Roaches, mice, rats, birds, squirrels, chipmunks, bunnies, racoon, dude, there are like so many things that wanna munch out on your food. Then there are humans. Don’t worry, the universe in her infinite fairness has allowed at least a chance that the people who eat your food might themselves be eaten as food by something. Which puts a whole different spin on storage and food in general. And it’s not like sharing isn’t fun and all but most of these creatures will urinate or defecate on what they don’t eat. Each one of these creatures has special talents and skills to try and sneak inside of your storage units. It’s a point separate from the cross-contamination each of these creatures represents. In this, we make the point that you and every other living thing is in competition for food and since you have a lot of it, you just made a whole pacel of new enemies. Controlling mice can be quite a headache as they just LOVE the idea of a dry indoor place with more food than they ever seen in their furry little lives and plus, you were kind enough to leave them all this sack and bag material to use for nesting! Mice have no sense of long-term planning atall. Given more than a mouthful, they decide it’s perfectly acceptable to urinate and defecate on the remaining hoards. Trapping them in the classic guillotine-type trap causes problems as you have just made a feast for the bacteria and whatever else Mr. Mouse has in him or on him and worse, flies love dead corpses and with flies come maggots. For mice and such I go for live or (humane) traps. Situate your trap on a piece of cardboard or something on the floor to catch droppings. You want that prisoner taken alive.
Things like bears can cause bigger problems. Doors to root cellars are generally thick. Humans can be even worse problems. Doors to cellars are often padlocked. It bears mentioning that in times of crisis, being known to have a lot of food stocked up could make you popular in all the worst ways. One good idea is not to tell anybody that you have a hoard. Another is to make sure your closest friends and neighbors are in on the deal. Give those who can help you defend it a stake in it. In troubled times, people will fight very, very hard to get food and to keep it.