As the beautiful lionfish devours native fish, the only way to halt its path: people
By Pam LeBlanc Austin American-Statesman Chicago Tribune 6.20.14
NOVA SOUTHEASTERN UNIVERSITY OCEANOGRAPHIC CENTER PHOTO Lionfish mature in a year and can spawn every four days, generating 2 million eggs annually. They live about 15 years.
GALVESTON, Texas — It sounds like something from a horror film: A beautiful, feathery-looking species of fish with venomous spines and a voracious appetite sweeps into the Gulf of Mexico, gobbling everything in its path.
Unfortunately for the native fish and invertebrates it’s eating, this invasion isn’t unfolding on the big screen.
In recent months, news has been spreading of lionfish, a maroon and white striped native of the South Pacific that showed up off the coast of southern Florida in 1985. Most likely, someone dumped a few out of a home fish tank.
With a reproduction rate that would put rabbits to shame and no predators to slow its march, the fish swept up the Eastern Seaboard and down to the Bahamas and beyond, where it is now more common than in its home waters.
“The invasive lionfish have been nearly a perfect predator,” said Martha Klitzkie, director of operations at the nonprofit Reef Environmental Education Foundation, headquartered in Key Largo, Fla.
“Because they are such an effective predator, they’re moving into new areas and, when they get settled, the population increases pretty quickly.”
The lionfish population exploded in the Florida Keys and the Bahamas from 2004 to 2010. As populations boomed, the number of native prey fish dropped. According to a 2012 study by Oregon State University, native prey fish populations along nine reefs in the Bahamas fell an average of 65 percent in just two years.
Lionfish appeared in the western Gulf of Mexico in 2010. The next year, scientists spotted them in the Flower Garden Banks National Marine Sanctuary, a protected area about 100 miles off the Texas coast. Now scuba divers spot them on coral heads nearly every time they explore a reef. Significant declines in native fish populations haven’t occurred here, but the future is uncertain.
“It’s kind of this impossible battle,” said Michelle Johnston, a research specialist at the National Oceanic and Atmospheric Administration in Galveston who manages a coral reef monitoring project at the Flower Garden Banks. “When you think how many are out there, I don’t think eradication is possible now.”
Lionfish are fascinating, beautiful creatures. Two nearly identical species are found in the Gulf. They grow to about 18 inches and have numerous venomous spines. Their stripes are unique, like those of a zebra. They hover in the water, hanging near coral heads or underwater structures where reef fish flourish. Ambush predators, they wait for prey fish to draw near, then gulp them down in a flash.
The fish mature in a year and can spawn every four days, pumping out 2 million eggs a year. They live about 15 years.
In the South Pacific, predators and parasites keep lionfish in check. But here, nothing recognizes them as food — those feathery spines serve as do-not-touch warnings to other fish. The few groupers that have been spotted taste-testing lionfish have spit them back out, Johnston said.
They can adapt to almost any habitat, from a mangrove in a foot of water to a reef 1,000 feet deep. They like crevices and hideaways, which they can find on anything from a coral head to a drilling platform to a sunken ship.
They can handle a wide range of salinity levels, too. Their range seems limited only by temperature — so far they don’t seem to overwinter farther north than Cape Hatteras, N.C., and their southern expansion extends to the northern tip of South America — although they are expected to reach the middle of Argentina in a year or two.
“As long as they have something to eat, they’ll be there,” Johnston said.
The impacts of their invasion could become widespread, scientists warn.
In the Gulf, lionfish are eating herbivores like damselfish and wrasse — “the lawn mowers of the reef,” as Johnston calls them
— that keep the reef clean.
“When you take the reef fish away, there’s not a lot of other things left to eat algae,” she said. That creates a phase shift from a coral-dominated habitat to an algae-dominated one. “When you take fish away, coral gets smothered, the reef dies, and we lose larger fish. It’s a snowball effect of negativity.”
In the basement of the NOAA Fisheries Science Center on the grounds of old Fort Croc kett in Galveston, Johnston sorts through a rack of glass vials. Each contains the contents found in the stomach of a lionfish collected in the Flower Garden Banks.
She points to a fish called a bluehead wrasse in one jar.
“This little guy should still be on the reef eating algae, not here in a tube,” she said.
Other jars contain brown chromis, red night shrimp, cocoa damselfish and mantis shrimp, all native species found in lionfish bellies. “The amount of fish we find in their guts — it’s really alarming. They’re eating juvenile fish that should be growing up. They’re also eating fish that the native species are supposed to be eating.”
They eat commercially important species, like snapper and grouper, and the fish that those species eat, too. They’re eating so much, in fact, that scientists say some are suffering from a typically human problem — obesity.
“We’re finding them with copious amount of fat — white, blubbery fat,” Johnston said.
Lionfish can eat anything that fits in their mouth, even fish half their own size.
Scientists don’t want to bring in another non-native fish to eat lionfish for fear of creating another invasive species problem, and sterilization programs are costly and logistically infeasible, Johnston said.
That’s why lionfish derbies, or fishing tournaments of sorts, are popping up around the Caribbean and Gulf. Locals are encouraged to kill and gather the fish, and in some places, including Belize, cook them up afterward.
A recent study, also by Oregon State University, found that native fish populations in the Bahamas grew by 50 percent to 70 percent on reefs regularly culled for lionfish. On reefs where they’re not culled, though, native fish populations decreased by an average of 50 percent. That seems to indicate that safe havens can be created where native species can recover.
“We’re never going to be able to eradicate lionfish, but there is a level where the population can be controlled and impacts can be limited,” said Klitzkie of REEF.
REEF has hosted six lionfish derbies in southern Florida and the Bahamas, and participants have collectively removed more than 12,000 lionfish since the series started in 2009. “We’ve found they’re really making an impact on lionfish population,” Klitzkie said.
In the Gulf, researchers like Johnston have special permits allowing them to remove lionfish when they spot them in the Flower Garden Banks sanctuary, but they need help. And that takes divers, boats and money. “It’s really an uphill battle. In times of limited budget, it can seem dismal,” Johnston said. “The second you stop, they come back.”
Another key to lionfish population control? Getting people to understand that lionfish are safe to eat — and tasty.
That word is slowly spreading. At least one Texas restaurant — the raw bar Cove, inside the Houston restaurant Haven — regularly puts lionfish on the menu.
Jean-Philippe Gaston, the chef at Cove, said some of the restaurant’s regulars, who are scuba divers, alerted him to the lionfish problem in 2011. Haven hosted a lionfish dinner to get the word out. When Cove opened in 2012, it became a menu staple.
“We serve it every day,” Gaston said. “A lot of people come in just for it.”
The fish is flaky and mild tasting, not fishy, and takes on the flavor of whatever seasoning it is prepared with, he said. It can be fried, poached, served raw, encrusted in peanuts, wrapped in leaves and steamed, or marinated in coconut milk with lemon grass, jalapenos, orange segments and ginger, just for starters. To prepare it, though, the cook has to snip off the spines before fileting it.
But for now, it’s an expensive fish for most restaurants to carry. That’s because the fish are usually spear-caught and difficult to handle. An accidental puncture causes swelling and localized pain.
A market might be developing, though. In Florida, local lobstermen are catching lionfish in their lobster traps and making more money selling the fish than the crustaceans, according to Klitzkie.
The organization publishes a lionfish cookbook that features about 100 recipes, from bacon-wrapped lionfish filets to fritters, ceviche, cakes and tacos made from the invasive species.
A gourmet appetite for lionfish would be good news for the Gulf.
“Order it,” Johnston said, tapping on the tank of the office’s resident lionfish mascot, a golf ball-sized fish named Woodstock.
“It’s the greenest fish you can get.”