LIONFISH, an invasive Pacific Ocean species, have been wiping out native fish populations in the Caribbean Sea and Atlantic Ocean for the past couple of decades. Now, research reveals the “terminator”-style approach to hunting that has likely made them so successful: When other predatory fish quit stalking their prey to look for easier targets, lionfish just keep on killing.

    “Lionfish seem to be the ultimate invader,” study researcher Kurt Ingeman, a doctoral student at U.S. Oregon State University, said in a statement. “Almost every new thing we learn about them is some characteristic that makes them a more formidable predator. And it’s now clear they will hunt successfully even when only a few fish are present. This behavior is unusual and alarming.”

    Ingeman, who presented his research at the annual meeting of the Ecological Society of America in Sacramento, California, studied populations of the fairy basslet, a common lionfish prey, at reefs in the Bahamas.

    Under normal conditions, the population of a small reef fish like the fairy basslet tends to fluctuate. These fish hide in rocks and crevices for shelter, Ingeman explained, meaning they become more difficult for predators to hunt when their population sinks to low numbers. But when predatory fish move on to other areas where prey are more abundant and thus easier to catch, the population of fairy basslets gets a chance to bounce back, and the cycle continues.

    Lionfish, which are covered in venomous spines, are such successful invaders because they can tolerate a variety of habitats and they reproduce at alarming rates. They also have a voracious appetite and aren’t too picky about what they eat. In some spots in the Atlantic, scientists estimate lionfish have wiped out 90 percent of native fish.

    In Atlantic and Caribbean waters, lionfish have no natural predators. Not even sharks could help curb the spread of the species, a study released last year found. Another recent investigation revealed that lionfish, thought to be confined to shallow environments, are thriving in surprisingly deep waters off the coast of Florida. (SD-Agencies)