The Rat Zapper is very effective at getting rid of mice and rats.... I had a red light blinking this morning when I went out (in the dark) to feed... saw about one inch of rat tail hanging out of the Zapper... it was a big fat one too. I also keep poison bait ("Just One Bite" is what it's called, best there is by far) available at all times inside a commercially-made (Tomcat) rat bait station. Don't EVER put out any kind of bait that isn't fastened down, or they'll just carry it off and hide it in their burrows. Also, rats seem to be great burrowers, I have seen them dig under a ten foot stretch of concrete to get at food. Rats are true athletes, they can climb, jump, dig and swim into places you can't even imagine.
I have a rat zapper that I used last winter out in the run. I put it into one of the plactic "rubbermade" type containers that is shoebox size and cut a door so that they could go in and the zapper could stay out of the weather. (They're made for indoors only and will be ruined if they get wet.)
BUT...
I brought it up to the back deck and garage in the spring because there was an over-population of chipmunks. I got a lot of them in that trap but...I missed one and let it sit in there too long. It began to deteriorate and the flies were having a great breeding time
It's never been the same since. I just haven't been able to get all the stuff off it perfectly no matter how I've tried to clean it. You have to be careful as you really aren't supposed to get it wet in there even though I did have to try....
So I get a lot of false alarms on it and it just isn't working up to par. I guess I need to get a new one.
So the moral of the story is.... BE SURE TO CHECK THEM DAILY AND DON'T FORGET! I loved it while it was working