The intentional and illegal release of unwanted freshwater aquarium and pond fishes is already a well-known problem, but new research suggests that the same thing might be happening with tropical marine fishes.
A survey by the University of Washington and the Reef Environmental Education Foundation found 16 non-native marine aquarium fishes living in the wild in the waters off the southeast coast of Florida, USA. The report's author, Brice Semmens of the University of Washington, says that this is an unprecedented number of non-native marine fish species for such a small geographic area.
The study, which combines data on both shipping and the aquarium trade, is the first to describe how the release of non-native marines can cause a hotspot.
Says Semmens: "Most of the species were seen at more than one place meaning more than just a few aquariums have been dumped, Semmens says. It is not clear which, if any, of the non-natives have established breeding populations.
"Typically, I'd say aquarium owners are more concerned with the status of our marine ecosystems than the general public is, yet many appear unaware of the potential pitfalls of releasing pets into the wild"
It has previously been suggested that fish or larvae trapped in ballast water of ships may also help disperse non-native marine fish species, however, Semmens thinks this is unlikely. The study found no link between the origin of the fish to the origins of ballast water in the ships entering Florida's ports.