I hate to kill things but I also dislike having mice and rats in my garage or shed. They are very destructive. I've found several tips on You Tube and other places online for killing rodents without using poison.
Using items that you may already have around the house I've found these work.
Recipe 1:
1 teaspoon flour
1 teaspoon sugar
I teaspoon baking soda
Recipe 2:
1 teaspoon flour or cornmeal
1 teaspoon sugar
1 teaspoon plaster of Paris (you can purchase at most craft stores or Walmart)
Note: They also like bird seed so sprinkle some on top. One recommendation for recipe 2 is to add water and make into dough balls. Another recommendation is to not put any poison/bait on anything metal or that moves. Put it on a hard surface.