Lionfish: ‘A plague that can be managed’

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By Mark Scohier, Staff writer

Venomous invaders from the South Pacific and Indian oceans are in the Cedar Keys area to stay, according to a scientist from the University of Florida.

But that doesn't mean they can't be managed.

Dr. Tom Frazer, an aquatic ecologist and director of the University of Florida's School of Natural Resources and Environment, spoke to a full house gathered at the Cedar Key Public Library Saturday morning about the spread of tropical lionfish in the area and around the world.

"I don't think you're gonna get anybody to say 'We're gonna' get rid of these guys,'" Frazer said. But the evidence suggests their numbers can be controlled.

Lionfish, according to the Florida Fish and Wildlife Conservation Commission, were first spotted near Dania Beach in 1985 and then in Miami, Boca Raton, Palm Beach and Bermuda in the 1990s. The fish are now reported to inhabit oceans along the Atlantic Coast as far as North Carolina, parts of South America, throughout the Caribbean and the Gulf of Mexico.

Frazer said it isn't known how the fish came to inhabit so many places around the world. They could have been released by saltwater aquarium enthusiasts or even caught rides on the wakes of large ships, he said. Nobody knows.

Lionfish, which are decorated with a zebra stripe pattern, can grow up to 15 inches — or larger in areas where they have no natural predators — and have long, venomous spines along their backs that can cause painful stings.

Frazer said there's no count on how established the fish are in areas such as the Big Bend, but divers have reported seeing them in the area for the last several years.

"There's every reason in the world to believe they'll become established here."

Frazer said the only real way to deal with their removal is through the use of spear guns. Traps don't work, he said, and lionfish won't bite on a fishing line.

A 2011 study done near the Caymen Islands showed that locals in the area, armed with spear guns, were effective in controlling the invasive fish's numbers, he said.

At first, islanders were bringing in up to 20 fish an hour per day, he said. But after about six months, that number was reduced to two per hour. And the average fish speared tended to be smaller and not at the age where it could have reproduced.

"We are demonstrating that we are having an impact on their numbers."

And the smaller fish that are left are eating "less commercially important parts of the food web."

Lionfish are, according to Frazer, extremely adaptable.

"They occupy all kinds of habitats -- coral reefs, mangrove forests, sea grass beds. This is a problem for us and something we need to be thinking about."

The fish, known specifically as the red lionfish, are also "voracious" predators and prolific breeders, spawning frequently and carrying up to 40,000 eggs at a time, Frazer said. And, along with their ability to inhabit many different environments, lionfish can live at varying levels within the water.

"This is a problem: trying to remove them at 100 feet, which is kind of a safe SCUBA limit, and then they're found at 400 feet or more."

Lionfish, according to FWC, have been reported at depths of 1,000 feet.

It was also believed at one time that the fish were sensitive to fluctuating levels of salinity, which might have kept them out of places such as Cedar Key, with its influx of fresh water from the Suwannee. But Frazer said lionfish have even been found near the mouth of the Suwannee.

The good news, according to some, is that it's open season on these tropical invaders. There are few restrictions on taking them from the wild, and there in no size or bag limit, which will help in the management of the species.

"It's gonna' take years and years and years to see how these communities are actually responding," Frazer said about lionfish populations around the world. "We don't know yet what's going to happen. We can't say they'll bring doom. We do know they can be managed."

For more information about lionfish or about harvesting, visit myfwc.com/fishing/saltwater/recreational/lionfish/.