Lionfish Atlantic Ocean Invasion
A Tropical Marine Aquarium Fish Establishes Itself in the Atlantic
Jul 13, 2008
The tropical marine lionfish (Pterois volitans) has recently become an accepted part of the temperate Western Atlantic seascape, and it appears the aquarium industry is to blame. Lionfish, indigenous to the Indo-Pacific, have now been reported in the Atlantic as far north as Long Island, New York, Massachusetts and Bermuda.
First Reported in the 1990s
The first reports of lionfish in the Atlantic occurred in the early 1990s, when several aquarium lionfish escaped into Biscayne Bay, Florida during Hurricane Andrew. While the hurricane-caused release was accidental, aquarists—both freshwater and marine—have a poor reputation for releasing unwanted aquarium fish and other animals and plants into natural bodies of water. The Caulerpa outbreak in Southern California is one such recent example, but there are, unfortunately, many others.
Releasing an Unsuitable Aquarium Fish
While lionfish can make very good tropical saltwater aquarium fish if the aquarist understands the fish’s needs and behavior, many beginning aquarists purchase young lionfish with little to no understanding of the animal’s behavior or environmental needs. When the growing lionfish begins to consume their other fishes, however, the aquarist realizes this is not a suitable fish for his or her aquarium and so releases the lionfish into the ocean as a means of disposal. This scenario is, unfortunately, all too common.
The First Established Indo-Pacific Aquarium Fish in the Atlantic
Luckily, most introduced, non-native tropical marine aquarium fish cannot survive the winter in the Western Atlantic, and so the species never becomes established. This is not the case with the lionfish. The lionfish appears to be the first example of a tropical Indo-Pacific marine fish species becoming established in the temperate Western Atlantic, and the consequences could be dire.
Dramatic increases in lionfish numbers from year to year over a wider and wider range suggests the species has adapted well to Atlantic life, and this is a real concern for fisheries managers. Lionfish are extremely effective predators, and, without any known predators of their own, the lionfish may well cause major and irrevocable damage to traditional Atlantic fisheries.
How They Survive
It is the warm waters of the Gulf Stream that have moved lionfish eggs and larvae north from sub-tropical Florida waters. The key to the lionfish’s success in the Atlantic is the Gulf Stream, where, at depth, winter temperatures remain warm enough to sustain the tropical lionfish.
Are Aquarists Really to Blame?
While some aquarists might like to shift blame away from the aquarium industry, it is pretty clear that the marine aquarium hobby is to blame for introducing the lionfish to the Atlantic. Other theories include lionfish larvae being transported in the ballast water of ships and even cross-ocean migrations (the lionfish migrated from the Indo-Pacific into the Mediterranean secondary to the building of the Suez Canal). Neither of these scenarios, however, is at all likely, and most experts agree that the expanding Atlantic population of lionfish originates from the marine aquarium trade.
What Can be Done?
While some favor eradication efforts, it seems unlikely that the lionfish will be effectively eradicated from the Atlantic through the capture of individual animals. This leaves marine researchers, marine aquarists, fisheries managers, and legislatures to determine what, if anything can and should be done to preclude any future non-indigenous species introductions secondary to the marine aquarium hobby.
Most important, marine aquarists need to be more conscientious and responsible in their pursuit of the hobby. The marine aquarium hobby can be a fantastic tool for reef conservation through raising awareness about the world’s oceans and the species that live in them. Irresponsible actions of a few, however, can lead to Draconian legislation that may shut the industry down once and for all.
 |
