When it comes to invasives, I can't help but think of one of my favorite mammals, the cat:
|Cat Mask, MR (papier mache')|
Did you know that some folk are trying to ban kitties from New Zealand? Yes, I mean from the whole country. Cats are hunting and eating too many of the native species, even when their bellies are full of yummy kitty chow. It seems when it comes to the non-native species we humans introduce, the phrase that comes to mind many years down the line is, "It seemed like a good idea at the time...."
I still love cats, though.