How to take care of nuisance wildlife, rodent and pest problems. This is Ed of Critter Control of Tampa Bay. What kills mice? Great question. There' a lot of toxins that are out there, a lot of different formulations of bait. The bait is put together so that it tastes good to the mouse. The bait will kill the mice. Normally, baits take two to five days to kill them. But you have no control over where they're going to die. That's my biggest objection to using poisons. But with mice, you may have to resort to using poisons. It will help to eliminate and further control the population. Right now, you can always use traps. Traps are designed to kill mice, also. In addition to Tom and Jerry, but the cat might be a good mouser, but he's only going to kill what he can eat. It doesn't even meet the control. These mice have four to seven pups per litter. They can have another litter in another month. They may have five to seven litters a year. That's an awful lot of mice. So, you have to eliminate the population as quick and thoroughly as you can. When you get frustrated, call a professional. This is Ed with Critter Control in Tampa Bay.