How clever and tough are Rats?
We live out in the middle of nowhere with most of Noah's Ark so we have Rats permenently. Amongst other things they have unscrewed bottle tops to get at animal suppliments, shown immunity to poison if we use the same sort all the time and regularly eat chicks and ducklings if not defended by their mothers. They also dig under or chew through anything that isn't metal and climb like Monkeys. As a rule I would never hurt another living thing but I dispise rats with such intensity that I have no qualms about killing them.
A few years ago we had Fox trouble but apart from trying to scare it off I would never dream of hurting it. We have also had Stoats kill chickens but we just put it down to nature doing what nature does which is OK......as long as it is not a Rat.
I can only put this down to reading the James Herbert horror novel "The Rats" as a teenager and the traumatic effect it must of had on me.