Lionfish and other invasives have proliferated the eastern seaboard and caribbean for some time now. I recently saw where 50 adult Lions were pulled off a shipwreck off the coast of NC. Pythons are becoming a problem in the everglades, I guess everyone has seen where the gator was eaten and the snake exploded.
In the summer the lions that have established a breeding population get sept up by the gulf current up to NJ and NY where they breed. However in the winter all the lions from NC up freeze.