Rat traps come in two varieties: lethal, and non-lethal. This discussion of rat control excludes rat poison, which probably won't work.

Non-lethal traps are more humane, and consist of a large box (something along the lines of a shoebox, maybe taller) with a spring-loaded sliding door triggered by a sensitive part of the box's floor. When the rat walks in to get the bait, the door snaps shut behind it. The rat is completely unable to escape, or do much of anything except for sheepishly eat the bait.

These traps are extremely effective. If you use one of these traps, be advised of several points:

  • Peanut butter is pretty good bait. Meat or cheese will rot quickly in the sun or be devoured by ants before the rats come after it. Same goes for fruit or vegetables.
  • Check the trap every single day. If you forget about the trap, you will one day come across a metal box containing a decomposing rat corpse. This is not only revolting, but also defeats your purpose of not killing the rat.
  • The rat is safe from predators, but might attract passing large animals (i.e. coyotes, stray dogs) with its constant scrabbling and banging around. Keep your cats indoors.
  • Take the trap at least 5 miles from your home when you go to release the rat, or else the same rat will come right back to your property. Sometimes they come back anyways.
  • The rat will be desperate. It's trapped, it hasn't eaten in many hours, and it's being flailed about as you take the trap away. Keep your fingers clear of the cage wire.
Lethal traps are somewhat less effective and pose some major problems, in particular the problem of disposing of the corpses, assuming you're brave enough to handle them. The usual trap is a larger version of the standard snap-neck mousetrap, but because rats are generally much larger than mice, the spring has to be much more powerful and the trap becomes more dangerous to set and manipulate. Lethal traps are generally more trouble than they are worth, because rats aren't as stupid as you think they are. Stick with live traps.