How Florida is handling invasive lionfish

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YASMEEN QURESHI: Florida's southern coast is one of the most popular dive spots in the world — home to the only tropical coral reef in continental United States. Hundreds of species of fish live along this reef system. But the fish here are in danger, because of a foreign predator that's been devouring them: lionfish.

YASMEEN QURESHI: Eric Nelson is an avid scuba diver who hunts lionfish up to a hundred and thirty feet below the surface of the Atlantic Ocean.

ERIC NELSON: They can eat 90 percent of their body weight, everyday, in fish. In fact, we have pictures of lionfish that have been gutted, and they have 50 small fish inside of them.

YASMEEN QURESHI: Nelson and his teammates are competing in a lionfish derby off the coast of Boca Raton, Florida. It's a competition to catch as many lionfish as possible before sunset. the boat's captain Paul Varian is a commercial fisherman who's been diving these waters for 16 years.

PAUL VARIAN: I saw my first lionfish 7/8 years ago, maybe. I remember going, "Oh woah! What's that? That's crazy." And now they're everywhere. There's so many of them.

YASMEEN QURESHI: Lionfish are native to the South Pacific and the Indian Ocean, and there are different theories about how they came to inhabit Atlantic waters. The leading theory is that a few home aquarium owners set some lionfish free in the ocean in the 1980s, and the fish rapidly reproduced.

YASMEEN QURESHI: Several scientific studies have traced the DNA for the entire lionfish population in the atlantic back to a small group of fish.

YASMEEN QURESHI: When lionfish invade a reef, they can reduce the population of fish they eat, by 65 percent over two years, according to a study conducted in the Bahamas.

YASMEEN QURESHI: How much of a problem are lionfish to the reefs in this area?

ERIC NELSON: Diving the same reefs over and over every year, you can actually really noticeably tell the difference between a reef that had lots of reef fish before lionfish invasion, and then devastatingly half as many reef fish.

YASMEEN QURESHI: Lionfish consume more than 100 species of fish, including baby grouper and snapper. And fish that maintain the health of the reefs by grazing on algae. Eric Nelson says he's noticed that the hunts off the coast of Florida are starting to make an impact.

ERIC NELSON: Once we started actively hunting lionfish, we noticed that the same populations are coming back.

YASMEEN QURESHI: During the past decade, lionfish have invaded the underwater habitats in the the Atlantic Ocean, the Gulf of Mexico, and the Caribbean.

YASMEEN QURESHI: Scientists expect that the lionfish invasion will continue to spread from North Carolina to the southern tip of Brazil.

YASMEEN QURESHI: One reason for the rapid lionfish invasion is that they are fast breeders — laying more than two million eggs every year.

YASMEEN QURESHI: Lad Akins oversees the lionfish program for Reef Environmental Education Foundation, that is dedicated to marine conservation.  

LAD AKINS: The marine environment is a very complicated, interconnected system and it's taken thousands of years for things to work its place out in balance. When you introduce a new piece to that puzzle, it disrupts the entire system.

YASMEEN QURESHI: Because lionfish are not native to the Atlantic, they don't have natural predators here. Akins says that when you combine that with their voracious appetites lionfish wreak havoc on underwater habitats. And, lionfish have been found as deep as a-thousand feet in the ocean.

LAD AKINS: With the impacts that we're seeing in our shallow waters, we don't know how bad this is going to get. So our entire marine ecosystem is at risk. We could see extinction of some species of fish due to lionfish predation. We could see severe degradation to coral reef environments, if algae is not kept in check by the grazers, which lionfish are consuming. We could see impacts to commercial fisheries, to grouper snapper, shrimp, crabs.

YASMEEN QURESHI: Without natural lionfish predators here, the most effective way to control the population is for divers to catch and kill them. But they're not easy to catch. They don't swim in large schools, and they have poisonous spines that can sting.

ERIC NELSON: This is safe, that's safe. They also have venom right on that one and that one, and then along pectoral there. The pain can be 50 times worse than a wasp sting.

ERIC NELSON: That's about an hour after being stung. That was in total, about a three-month ordeal.

YASMEEN QURESHI: The dive community has stepped up to find safe ways to catch lionfish. One diver designed this plastic cylinder that he calls a zookeeper to store lionfish underwater, and protect divers from being stung. Nelson and his team use pole spears that he adapted to make it easier to catch the fish. He calls them "lionfish slayers".

LAD AKINS: What's great is that everybody is pitching in to address this. Divers are going out and spending their time, and their money to go out and remove lionfish; governments are putting money and effort into researching better tools and techniques.

YASMEEN QURESHI: Florida's Fish and Wildlife Conservation Commission has been running a public awareness campaign about the lionfish threat and contributing prize money to derbies to catch them.

YASMEEN QURESHI: As this lionfish derby comes to an end, the dive teams head back to the dock for weigh-in. Lad Akins organization, Reef, is one of the sponsors of the event. He says derbies can help scientists better understand the species.

LAD AKINS: Every individual lionfish that's collected is measured, because that information is very useful in looking at impacts and populations. And then samples are made available for researchers that are hoping to better understand lionfish.

YASMEEN QURESHI: Some fish is also donated to restaurants to create a human appetite for lionfish. Chef Andres Avayu at Piccolo Restaurant in Fort Lauderdale says his customers line-up for tables when the specialty item is on the menu.

ANDRES AVAYU: You could grill it, sauté it, bake it- like it's flavor, it's really versatile in how preparation is done. There is no right, there is no wrong. It's one of those fish that just is.

YASMEEN QURESHI: One of his favorite recipes, lionfish tacos. And fisherman have noticed that catching lionfish can be profitable. Commercial fisherman Paul Varian, says demand is increasing. Even Whole Foods sells them, when available.

CAPTAIN PAUL VARIAN: They've become a pretty big part of my income. The last year or so; everybody's finally figured out that the guys who buy them from us; the restaurants; the consumers; everybody likes them and it's worth it. Everybody's making money and the consumer is happy at the end. So now, the price has gone up. Demand has gone way up. I have people calling me, I don't even know who they are, begging me to buy lionfish. And I'm like sorry, I'm just supplying the people I've been selling to for years. If I could shoot a thousand pounds a day I could sell it.

YASMEEN QURESHI: As the results come in from the weigh-in at this derby, some people are tasting lionfish for the first time.

KAREN SCHROEDER: I'm a scuba diver, and I've seen them underwater for a long time. And everybody has been telling me it tastes like hogfish. It's a nice light, white, crispy fish, and a very mild flavor.

YASMEEN QURESHI: Lad Akins says popularizing lionfish cuisine, may be the best way to control the problem.

LAD AKINS: Eradication is not on the table. Lionfish are simply too widespread, too deep, too inaccessible in some areas for us, with our current tools and technologies, to remove every last one. So what we're left with is having to keep de-weeding the garden.

Florida Fish and Wildlife Conservation Commission, Carolina and Ricardo Valera and Reef Environmental Education Foundation contributed underwater footage.

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