Why do you want live rat traps? I once bought some rat traps that looked like mouse traps only bigger. When them things went off, the earth moved.
Good traps. Or, nail a couple of those sticky traps to a board and bait it. You'd be suprised at what they'll hold. You might try putting your feed in metal trash cans too...with lids.
We cannot continue to do the same things and expect different results