By John Dawes

Red lionfish (Pterois volitans) are beginning to appear along U.S. Atlantic coasts. (Photo courtesy of John Dawes)

“Venomous Lionfish Prowls Fragile Caribbean Waters.” So reads the dramatic headline recently in an Associated Press story posted this past August. According to the report, “A maroon-striped marauder with venomous spikes is rapidly multiplying in the Caribbean’s warm waters, swallowing native species, stinging divers and generally wreaking havoc on an ecologically delicate region.”

The article quotes an Oregon State University marine ecology expert, Mark Hixon, who says, “This may very well become the most devastating marine invasion in history.” After comparing the "invasion” to a plague of locusts, he says, “There is probably no way to stop the invasion completely.”

Adding further to the sensationalized image, Bruce Purdy, a dive operator in the region, says, “...at the best they will have a huge impact on reef fish, and at the worst will result in the disappearance of most reef fish.”

While there is no denying that red lionfish (Pterois volitans) have been appearing on a fairly regular basis along the U.S.’s warmer Atlantic coastlines, it is doubtful the alarming picture being painted is an accurate one. It is also unlikely that all these exotic lions have come from a single source.

Indeed, there is considerable debate regarding the origins of these exotics. Some say aquarists have intentionally released them, or they have accidentally escaped from private aquariums. There are also those who think lionfish were released by ships discharging ballast water, while others suggest some inventive tour operator ”planted” them in selected sites to make diving more interesting.
The U.S. National Oceanic and Atmospheric ¬Administration (NOAA) states the original source was a private aquarium in Miami that was shattered during ¬Hurricane Andrew in 1992.

NOAA scientists say six specimens found their way into Biscayne Bay and the floating sacs of eggs these produced were dispersed by the Gulf Stream. The debate is of little practical value in the face of what may be becoming a growing problem in the region.
The ornamental aquatic industry, for its part, can do nothing to prevent ships from releasing ballast water, or unscrupulous operators from attempting to make their diving sites more interesting. We can offer advice, both to suppliers and consumers, via our trade organizations.

All our representative bodies are firmly and unequivocally against the release of any aquatic organisms, whether plant, vertebrate or invertebrate, into the wild. Whether that advice is taken up or not, either by everyone in the sector, or by kind-hearted (but misguided) aquarists wishing to ”liberate” their charges, remains, however, a different matter altogether. <HOME>

John Dawes is an international authority on fish, aquariums and outdoor fishkeeping.