The anti-freeze method is tempting, but I love little critters a lot, even the pests. It's quite inhumane. There are poisons out there that do the job much quicker and with less pain to the critter.
I've got a plumber building his new business location adjacent to my property (his, recently rezoned Commercial from AG). He ripped out several hundred trees this past week, which resulted in a delicious smorgasbord for my 12-yo cat! An endless selection of prime squirrels, field mice, snakes and lizards to feast from! Unfortunately, they come into the shop, too, so I've been hyper-vigilant about the invasion of furry creatures into my realm. My dog seems to prefer gophers and voles. She'll tear the hell out of those! It's fun to watch a 125# Boxer/Mastiff mix dig down, snatch the tasty little varmint from its warm home and into the death grip of her warmer mouth!