up in chicopee mass my buddy had a squirrel problem, and he trapped a few. he did something to them to kill em quick (pellet gun? poison? I cant remember). He asked his neighbor for his opinion on the problem and the neighbor told him it was city ordinance to drown them. like, keep them in the cage and drop the cage in a bunch of water. apparently somehow it was considered the most humane and best way. I dont know how I feel about that (maybe it was the best way, I dont know), but I helped with one of the squirrels and I felt pretty bad, he struggled like a motherfucker.
1st world people are weird about stuff like that sometimes, its just a rat really, we shouldnt care so much.