Eradicating Lionfish - Sailors for the Sea

Eradicating Lionfish

By: Tyson Bottenus, At-Large Ambassador for Sailors for the Sea | February 13, 2017

Can humans stop the lionfish invasion?

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Have you ever seen a lionfish?

If you have, and you were in the Atlantic Ocean, you have witnessed one of the fastest spreading invasive species problems in the ocean.  With eighteen spines protruding off their body, lionfish appear beautiful and exotic but these pervasive creatures have a voracious appetite and those venomous spines can cause serious pain. Both attributes make them dangerous to coral reefs and to the species that inhabit them. Their appetite allows them to decimate the population of other reef fish and the venom stored in the tips of their needle-like dorsal fins makes them difficult for humans to hunt. In the Atlantic Ocean, where they have no natural predators, they live up to their full potential to wreak havoc.

If you read our previous article, the Lionfish Invasion, you’ll know that lionfish are native to the Indo-Pacific region. So how did they travel to the other side of the world? The exact story is unclear but genetic testing has confirmed that Atlantic lionfish descended from about 10 original lionfish that were released in south Florida in the early 1990s. Since then, they have been found up and down the Eastern seaboard and as far south as South America.

Since we published this story in 2011, lionfish have continued to spread and recently have been found as far away as the Mediterranean Sea. But increased awareness of the problem has lead many Caribbean islands to promote competitions to catch and kill as many lionfish as possible. Some forward thinking restaurants have even started offering lionfish on their menus.

Beautiful Fish or Dangerous Demon?

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When you fish look at a lionfish, it’s hard to imagine them as horrific threats to coral reef health. Aesthetically speaking, they are simply majestic-looking creatures. But beauty aside, there are many factors that explain how they were able to quickly expand their population and why humans are stepping up to undo our own mistake.

Five reasons lionfish cause so much trouble:

1.     Lionfish eat. They eat a lot. Known to prey on over 70 different species, lionfish are particularly adept at eating juvenile fish, like parrotfish, who consume algae that grows on coral reefs. These fish play an important role in keeping reefs healthy, and without them, entire coral reefs suffer.

2.     Like underwater rats, lionfish can live pretty much anywhere. Some have even been found at depths up to 300 meters. This kind of dynamic habitat range makes studying lionfish extremely difficult for marine biologists.

3.     Since they aren’t recognized by their prey in the Atlantic (like they are in the Indian and Pacific Ocean), they have become a very effective predator. Additionally, their slow movement and seaweed-like appearance acts as a natural camouflage.

4.     It’s estimated that lionfish have been able to populate a million square miles of ocean in 10 years. They become sexually mature in their first year and females spawn 4,000 to 30,000 eggs every few days or so.

5.     Lionfish like to make their homes in the natural crevices of coral reefs. They don’t school and aren’t easily attracted by bait. The only way to catch them is through spearfishing, one at a time, reef by reef. Gathering enough to sell to a restaurant or market can be a challenge. However as the interest in eating them grows, fisherman are able to dedicate more time to catching them.

As governments realize the potential harm posed by lionfish to coral reefs, many individuals, governments and nonprofits have come up with creative strategies in an attempt to regulate the further spread of the species.

How Aruba is Tackling Lionfish

When it comes to diving, most island nations in the Caribbean have worked hard to keep the diving community strictly focused on diving and not fishing. But as lionfish continue to spread and their population continues to grow, many communities are beginning to change laws to make exceptions for divers to hunt lionfish.

“Many divers have put quite an effort into reducing the impact of lionfish on our fish population,” says Eric Mijts, local sailor, diver, and Clean Regatta Organizer for the Aruba International Regatta. “I know of quite a few individuals and also some dive schools in Aruba that actively promote or participate in lionfish hunting.”

Many of these divers link up via Facebook groups around Aruba, says Eric, taking part in what’s become known as “lionfish derbies” to go around different reefs and cull as many lionfish as possible. On a typical day, some of these expeditions can engage between 10-20 divers and can eliminate more than 100-150 lionfish at a time.

To make the incentive greater, many restaurants have expressed an interest in serving lionfish on their menus. One organization, Aruba LionFish Initiative, has begun offering to purchase lionfish in bulk in order to create a burgeoning market for the fish. Silver level certified Clean Regatta, Aruba International Regatta, for many years now, has sponsored lionfish hunting competitions and has served lionfish ceviche at their event.

However, if you are traveling to the Caribbean, don’t expect that you can simply go spearfishing for lionfish in the name of ocean conservation. Many of the islands that we researched have implemented some sort of special dive certification to ensure that those who are hunting lionfish do so in a responsible manner.

Marine biologist and dive operator, Trevor Brown, who has extensive experience diving with lionfish in the Bay Islands of Honduras, says that hunting lionfish can also have unintended impacts.

“Numerous times I’ve seen inexperienced divers trying to spear lionfish and unintentionally damage the reef. They simply lose control of their buoyancy and kick the reef accidentally.”

Mijts echoes a similar vein of optimistic caution as well.

“Of course, to be honest, we can not balance between human impact and lionfish until we get some serious longitudinal research done.”



Spearing lionfish not only requires a license in most places, it requires years of practice snorkeling or diving, knowing how to control your weight, fins and speargun without damaging coral.

Hunting Lionfish With… Robots?

Another island country where lionfish have become a pernicious problem is Bermuda. With 280 square miles of coral reef, it has become a hotspot for lionfish to take up residence. In 2013, the Living Reef Foundation estimated that Bermuda’s reefs made up an estimated 10-17% of the country’s GDP. With something this precious at risk, Bermudians came up with a plan to protect their marine ecosystem.

In 2012, the Bermuda Lionfish Taskforce was assembled in order to get government officials, scientists, fishermen, and the private sector together to combat the spread of lionfish. Their efforts at raising awareness of the problem have been extremely successful as have their efforts, like Aruba’s, to relax fishing laws to encourage the selective hunting of this species.

With the America’s Cup right around the corner, there are a few initiatives planned to educate and engage spectators about the lionfish problem. Landrover BAR skipper Sir Ben Ainslie and Chef Rob Ruiz, hailed as the 2016 Chef of the Year by the San Diego Tribune and recipient of the 2016 Ocean Award for his dedication to responsibly-sourced seafood, will be teaming up together for the #EatLionfish Chefs’ Throwdown. The two will learn how to hunt lionfish as well as how to prepare flavorful dishes.

But one of the most curious approaches to answering the problem of lionfish will get a huge boost of awareness from the America’s Cup. RISE (Robots In Service of the Environment) will be on hand to showcase low cost underwater ROVs (remotely operated vehicles) that the organization is developing to recognize and electrocute lionfish populations at depths up to 1,000 feet.

One of the cofounders of RISE is iRobot CEO Colin Angle, who came up with the idea after diving in Bermuda and witnessing the invasive problem firsthand. Currently, RISE has developed two prototype designs, which they are in the process of testing.

“The first device will be remote controlled,” says RISE executive director John Rizzo in an interview with NewsAtlas. “It will be on a tether and we’ll drive it from above.”

Of the two prototypes, one works by positioning two metal electrodes on either side of the lionfish’s body. Once centered between the electrodes, the robot releases a surge of electricity great enough to stun only the lionfish. What RISE has found is that the prototype works well because of the lionfish’s slow behavior. Unlike other fish that live on coral reefs, lionfish surprisingly show little regard when a large robot is able to position itself close by. Once stunned, the robot is able to scoop up the lionfish into a holding cell.

RISE claims that of its partners, which include the Government of Bermuda, the Bermuda Lionfish Taskforce and the Bermuda Institute of Ocean Sciences, they have developed nearly 16 million robots. A majority of these robots are Roombas, the popular autonomous home vacuum cleaner first developed by iRobot in 2002. All of this begs a serious question: can a robot really solve this ecological nightmare?

However, with lionfish spreading so rapidly through the ocean, and reproducing so quickly, it seems worth the shot. Any effort, from engaging the diving community, to teaching chefs, and – so it seems – to building robots, must be encouraged, must be tried, must be promoted, and then, only then, will we might have a chance at reversing the spread of a species that’s been dubbed “Darwin’s nightmare.”


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