Money might not be enough to stop the lionfish invasion

Can a tax on dive tourists stop the lionfish invasion? Read the story from Hakai.

I wrote a longer version of this story for my master’s portfolio at the University of Montana. You can read that here.

The first lionfish in Cozumel, an island off Mexico’s southern coast, appeared in 2009, but according to dive shop owner Guillermo Mendoza it didn’t last long. When Mexico’s National Protected Areas Commission sent out an email to report the sighting, he said local divers fashioned spear guns from bike spokes and set out to find it.

“We thought it was just one of those strange cases where it escaped from someone’s aquarium,” he said of the species known for its striking color and showy pectoral fins..

But then there was another, and another. Before long, Cozumel Reefs National Marine Park was infested with invasive lionfish. The fish eat many forms of smaller fish and slowly strip coral reefs of their diversity.

Now, some conservationists and scientists are trying to fight back.

They have suggested levying a fee on divers in the resort region to help pay for a stronger response, which could include hiring more national park employees to monitor and hunt the fish. While the fee is intended to protect the reefs that the tourism industry relies on, dive shop owners like Mendoza worry it would also scare away cost sensitive visitors. Other scientists argue it’s too late to eradicate the fish anyway because fishermen with harpoon guns—still the best way to kill the fish—can’t get to deep water reefs, where many lionfish live and reproduce.   

Lionfish are native to the Indian Ocean, but scientists think dissatisfied aquarium owners started dumping them into the Atlantic in the 1980s. From there, they spread quickly throughout the Western Atlantic and into the Caribbean.

They herd prey into corners using poisonous, brightly colored fins, and scientists think native fish haven’t learned how to respond to this tactic, which makes them sitting ducks. Lionfish occasionally each other, but otherwise they don’t really have any natural predators in the western hemisphere. In contrast, they will eat almost anything they can fit in their mouths, including native species—such as parrotfish—that graze on algae growing on coral reefs. If there aren’t enough of these grazers, algae can take over the reef and kill the coral.

That’s bad news for the region that houses tourist destinations Cancun, Playa del Carmen and Cozumel because its economy depends on coral reefs to attract visitors. Last year, the state tourism agency reported that visitors brought in more than $8 billion dollars, representing about half the state’s economic output. According to a recent report conducted by Mexico’s National Protected Areas Commission, Cozumel could see a 12 percent drop in tourists—a loss of $83 million annually—if the degradation of its coral reefs continues.

But controlling the lionfish is expensive. Hunting them one by one with harpoons is the best method, but the national park doesn’t have enough people to carry out such a cull.

To make up for the financial shortfall, Luis Malpica Cruz, a marine scientist at Simon Fraser in British Columbia, has proposed a new fee on visitors to the national park to pay for people to monitor and kill lionfish. In a new paper, he found that most tourists would be willing to pay a $5 fee, but were less likely to pay more. He also discovered that most tourists prefer healthy reefs with few lionfish.

“I guess the dive operators will have to consider what they want to do,” Malpica said. “But if the numbers start to increase, we are showing that some divers might not like to dive … those reefs anymore.”

He admits that the fee could discourage divers from visiting Cozumel, but in the long run, raising money to fight the lionfish might save the reefs and, ultimately, keep dive tourism alive.

Even before Malpica published his paper, the Cozumel Reefs National Marine Park was considering a reef conservation fee. Everyone who enters the park already pays an entrance fee of about $1.75, but that money goes to the federal government, not the park. The new fee would fund the park in Cozumel directly.

But the fight for a fee appears to be a difficult one. The park’s director of surveillance and biological monitoring, Diana Martinez Gonzalez, said Cozumel is one of Mexico’s most visited parks, and the entrance fees help fund other parks across the country.

The park’s director Christopher Gonzalez said entrance fees at Cozumel generate about half a million dollars each year, but only about a tenth of that comes back to the park. The park employs 13 people, and he doesn’t think that’s enough to keep the lionfish in check. He’s hesitant to impose a tax on tourist to fund the park, but doesn’t have many options.

“The last (option) is the application of taxes or the application of extra costs on the tourist,” he said.

And the idea of fees to protect has a mixed history in Mexico. In 2016, Researchers from Mexico’s Center for Biological Investigations of the Northwest recommended raising the roughly $1.40 entrance fee at the Sierra la Laguna Biosphere Reserve in Baja California Sur by 200 to 300 percent. Now, the entrance fee is $0.84.

Researchers from Mexico’s Ecological Institute calculated that people visiting the Punta Cancún-Nizuc and Isla Mujeres National Park, about 40 miles northeast of Cozumel, would be willing to pay an entrance fee of almost $8. Right now, visitors pay about $1.68.

When asked about an additional fee for tourists, Guillermo Mendoza—the dive shop owner in Cozumel who made his own spear gun out of bike spokes—just groaned. He says the additional fee would drive customers away, and add another layer of bureaucracy to running a business. He says lionfish aren’t as big of a plague as they’re made out to be, adding that while he sometimes takes customers lionfish hunting, they rarely find them.

“There are 2,000 to 3,000 divers a day here during peak season,” Mendoza said. “You can forget about the lionfish. There may be one on the reef, but it doesn’t even last a week … before it’s dead.”

The local fishing cooperative agrees that lionfish are already under control. The co-op has been aggressively targeting lionfish since the invasion began in 2009. That year, co-op fishermen reported hauling in 700 to 800 kilograms of lionfish each month. In subsequent years, that dropped to less than 50 kilograms per month. Restaurants around the island have started serving lionfish, and it’s now the second most important fishery on the island after lobster, according to the protected areas commission.

Mendoza said the decline in the lionfish catch shows that the fishermen are doing a good job of controlling the invaders. But even this targeted effort—fueled by a growing demand for lionfish meat—has failed to eliminate them completely.   

That’s why Alfonso Aguilar-Perera, a lionfish expert at the Autonomous University of Yucatán, Mérida, says the entire debate about a fee to pay for more lionfish hunting is fatally flawed. He argued that because lionfish can live deep beneath the surface, many avoid fishermen’s harpoons.

In Alacranes Reef National Park, on the northern side of the Yucatán Peninsula, Aguilar-Perera found lionfish on twilight reefs—ecosystems more than 100 feet below the water’s surface that contain light dependent algae and coral as well as organisms that usually inhabit areas without much light. He could only spend nine minutes at that depth before running out of air, so one researcher speared lionfish while a second researcher just counted.

Other researchers in the Bahamas used remote operated submarines to document the presence of lionfish almost 600 feet below the surface. At that depth, no human diver can spear them.

“It’s like a weed. You cut it and you cut it … but it’s always going to be there unless you attack the root,” Aguilar-Perera said. “In the case of the lionfish the root, as an analogy, is the fact that it reproduces in areas that are inaccessible to divers.”

He compared the problem to Mexico’s seemingly endless drug war. You can arrest the leader of a drug cartel, but there will always be someone else to take his place.

Cozumel’s only hope, he said, is if the island’s native predators develop a taste for lionfish. If that happens, they won’t disappear entirely but they might become part of the current reef ecosystem. It’s a hail Mary pass, but divers have documented native groupers killings lionfish in the Cayman Islands, and Aguilar-Perera said if native predators can control lion fish numbers the reefs might stand a chance. 

Photo by By Alexander Vasenin (CC BY-SA 3.0)