Deep Trouble

3613753961_0521271a04_oWhen a submersible dove into deep waters off Florida not long ago, the scientists aboard saw an alarming sight: big lionfish, lots of them. “This was kind of an ah-ha moment,” says OSU researcher Stephanie Green. “It was immediately clear that this is a new frontier in the lionfish crisis.”

Lionfish, native to the Pacific Ocean, are invaders threatening reef ecosystems in the Atlantic and Caribbean. But until scientists onboard the vessel Antipodes witnessed the extra-large, extra-fertile fish thriving at 300 feet deep, they didn’t realize just how extensive the invasion had become.

A lionfish, with its festive stripes, flowing fins and spiky rays, cuts a dramatic figure in a home aquarium. But in coral reefs outside its native waters, it is an ever-growing scourge, gobbling up smaller fish and reproducing at alarming rates. Accidentally or deliberately released from aquariums a decade or more ago, lionfish have no natural predators in their new environment. They have taken full advantage. “A lionfish,” says Green, “will eat almost any fish smaller than it is.”