Penning up your gardens in 10 by 20 foot cages and letting 2 or 3 chickens go inside everyday until harvest season goes a long way toward keeping out pests as large as mice.

Another good food source for those with the right piece of land is a small pond of catfish or bullhead.

You only need around 4' of water and can harvest with a friend and a net once a year.Alot of bang for the buck after the initial expence of digging the pond.Leave some good tall grass about a foot thick all the way around and there will be more than enough insects to keep bullhead happy and fat.

Good place to dump those chicken guts and small game leftovers to.