Mealworms
You are going to get the usual trifecta of rabbits, goats, and tilapia from most preppers, which I am inclined to agree with. However, you asked for wild.
Mealworms are worthy considerations for many reasons. One: Easy to raise. Lots of us reptile owners have raised our own for sometime.
Two: The rearing of mealworms requires very little room. They are generally raised indoors which suits OPSEC just fine.
Thre: They are a nutritional powerhouse. As a grub ( immature beetle ) they are growing and putting fat in storage for eventual pupation where after a certain period of time they hatch as a mature adult beetle. An easy cure for the dreaded 'where do I get fat from?".
Four: Cost of food to raise mealworms is minmal. You simply put about two to three inches of oatmeal,or oat bran, or wheat bran, or cornmeal, or whole wheat flour some calcium, as growth stimulate which can easily be from bone meal, Brewers yeast, or readily available reptile powders from pet stores.
So there is a significant source of easily raised, cheap, OPSEC friendly and nutritious source of food. Oh, and the taste? If pan fried, alot like popcorn

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