Mink are fierce predators. I have personally seen a large one take down an adult rabbit (the screaming was unnerving until he switched from holding a leg to its neck). This year, I saw one climb a tree and check out a pine squirrel tree hole. Nobody was home at the time but when the owner returned he acted pretty agitated (must have been the smell lefty behind). Saw a second one about a quarter mile away on a another stream a couple days later (could have been the same one but unlikely). My neighbor traps several on my place each year, but I like having some around (not so much when I had chickens).