Sounds like they are trying to get at things like the Snakehead fish.
Burmese pythons have decimated the native mammal population in the FL Everglades. Initially introduced into the Everglades by either accidental or intentional release of a "pet" python, thousands of the invasive species are removed annually. Other well known invasive species in and around Florida include the destructive Lionfish, the Giant African snail and the Cuban tree frog.
Invasive Species: A plant or animal species that has been introduced to an environment where it is not native, and that has since become a nuisance through rapid spread and increase in numbers, often to the detriment of native species.