Lionfish (Pterois miles and P. volitans) are native to the Indo-Pacific but in less than a decade they have flooded the waters along the Southeastern U.S. and Caribbean. This highly invasive species is becoming one of the biggest threats to our oceans as it out-competes commercially important fish species and alters whole reef communities. For more background on lionfish, check out this article.
In order to address the lionfish problem in Bermuda, a group of scientists, researchers and environmentalists is creating a lionfish exhibit at the Bermuda Underwater Exploration Institute that highlights the impact of lionfish and how Bermuda plans to address the issue. MST recently had the chance to speak with Corey Eddy who is helping out with the exhibit.
Corey Eddy is a graduate student at the University of Massachusetts Dartmouth. He is also a fellow through the National Science Foundation’s Graduate Research Fellowship Program and the Academic Liaison for the Ocean Support Foundation. As part of his doctoral thesis, he is working with the Bermuda Lionfish Task Force to study the ecological impact of lionfish upon Bermuda’s marine environment.
Below, you will find the full Q & A with Corey Eddy and the Bermuda Underwater Exploration Institute (BUEI) about invasive lionfish. For a shortened version, click here.
Q- How did lionfish end up in the Caribbean and Atlantic? Is it true that people released them from aquariums?
Yes, it appears to be true that lionfish were first introduced from personal aquaria, although we can’t say whether that was intentional or accidental. For a long time, it was suggested that a lionfish tank at someone’s home near Biscayne Bay was damaged during Hurricane Andrew, thus releasing the lionfish, but we actually have records that indicate lionfish were first seen in 1985 near Dania Point, Florida. So that’s how they were first introduced. The current thought is that the eggs and larvae of lionfish were then dispersed via the Gulf Stream along the US coast and toward Bermuda. The mechanism by which they reached the Bahamas is more complicated and took far more time.
Q- How many lionfish are there today and how was their population able to grow so quickly?
It’s really hard to answer the first part of this, as no one has actually estimated the overall population. That being said, researchers have seen lionfish in incredible abundances throughout their invaded range. For example, at sites in the Bahamas, there are more than 390 lionfish per hectare, which is about five-times as many as would be found in their native range. At deep sites around Bermuda, in the range of 200 feet, technical divers have been able to collect 30 lionfish from an area only as large as a classroom. So overall, it’s hard to guess the population, but I would offer tens of thousands as an incredibly cautious estimate.
Genetic analysis suggests, at the low-end, it is possible this whole scenario developed following the introduction of 8-12 individuals at one location. That being said, it could have been more introductions of more individuals, but that estimate is theoretically possible. The population has been able to grow incredibly fast because of the biology and ecology of these predators. First of all, mature females can release up to 30,000 eggs at each spawning event, and these may occur every four days. The egg mass itself is actually gelatinous and buoyant, which allows it to float near the surface and be dispersed wherever the currents flow. This incredible population growth has continued unfettered because lionfish have no known predators in the Atlantic Ocean, so there is no alternative except that humans target them to limit their numbers.
Q- Why should we be concerned about this? If nothing is done to keep the lionfish population in check, what will happen?
The invasion of the Indo-Pacific lionfish could rank as the worst environmental catastrophe in the Atlantic this century, if it is continued run uncontrolled. The biggest concern, not to minimize their reproductive success, is their voracious, indiscriminate appetite. They are generalist predators, meaning they will eat anything, and they are opportunistic, meaning they will eat at every opportunity. Taken together, they are non-stop eating machines. In Bermuda, we have seen lionfish with over 30 juvenile fish in their stomachs, but other people have seen twice that. They are known to eat about 70 different species, those important both ecologically and economically, such as fish, shrimp, crabs, and lobsters. To avoid confusion, they eat the juveniles of large species, such as grouper and snapper, but also adults of the smaller species, such as cleaner wrasse and gobies. As such, they could cause declines in the populations of everything they eat. By eating cleaner fish and shrimp, which eat parasites from other fish, they can negatively affect the health of many fish species, with consequent effects throughout the environment. A text book example of the worst case scenario is something we call a trophic cascade. For example, if lionfish eat all the herbivores, such as parrotfish, which eat algae from the reefs, the algae will grow out of control. If this occurs, the health of the reef will suffer and the corals themselves could die.
Q- I’ve heard the “Eat ‘Em to Beat ‘Em” phrase a few times now. Is that really the only way we can combat this highly invasive species?
Sadly, yes. With no predators eating them, the only solution is to make them into a commodity, create a fishery, put them on dinner plates, and then overfish their population. It’s ironic. It’s the inverse of fisheries management. Typically, we want to limit fishing effort to allow fish populations to grow for the sake of a healthy ecosystem. Here, we want to maximize the effort to minimize the population for the same outcome.
Q- What about lionfish derbies? Do the fish caught in those tournaments get eaten or are they just collected and discarded?
Tournaments typically include prizes for different categories, such as largest, smallest, and greatest number. I’m really not sure how it’s done in places around the Caribbean and the US coast as far as the fate of the captured lionfish. However, in Bermuda the fish are dissected, fileted, and served to the audience. I think that is likely par for the course. Like in most places, we focus on education and outreach for these events, so we want to show everyone what we do with each fish in terms of research, but we want to emphasize that they are a healthy, delicious seafood choice.
Q- Are the spikes on the lionfish in any way dangerous to humans? Do they make it more difficult to catch and/or cook a lionfish?
Yes, the spines are absolutely a danger to humans, but not as severely as some people think. Because of the venomous spines, a lot of people get the wrong impression and think the flesh itself is toxic or that one sting is enough to kill you. Both those thoughts are wrong. That being said, the spines are dangerous. The venom itself packs a pretty severe punch that has been described to be similar to several bee stings. Lionfish are very easily caught with any sort of spear, which then makes the fish pretty easy to handle as they are dead. If someone were to catch a lionfish by hook and line, which is far less common, that fish becomes more difficult as it is likely to still be alive with a lot of energy. It’s a similar situation when lionfish are caught in lobster traps. When lionfish are dead, they’re pretty easy to handle, as long as you are aware of the spines and take caution. When they are alive, it is more difficult to handle to handle one.
Q- The Bermuda Underwater Exploration Institute (BUEI) is opening a new Lionfish Exhibit on May 15. What will the exhibit include and will it be open to the public?
The exhibit is intended for a general audience and will be open to the public. The exhibit explains how lionfish were introduced to the Atlantic, why they are a problem, how bad the problem might get, and what people can do about it. It gives information about the fish itself, including a tank with live lionfish that is part of a research project being carried out by Corey Eddy and there is a station where school tours can observe a lionfish being dissected. To lend perspective there are also displays about invasive species in Bermuda and other aquatic invasive species. The exhibit will be accompanied by a series of topical lectures over its five month run.
Answered by the Bermuda Underwater Exploration Institute.
Q- What do you hope to accomplish by opening this exhibit?
A significant goal is to inform the local population about the lionfish invasion, but it is also hoped that the exhibit will increase awareness of the threat posed by invasive species generally and thus decrease the potential for future introductions.
The exhibit was developed by the Bermuda Underwater Exploration Institute in support of and in collaboration with the Bermuda Lionfish Task Force, a broad coalition of stakeholders tasked with promoting awareness of the lionfish invasion and working to find a solution. Several members of the Taskforce are actively studying the biology and ecology of lionfish, their ecological impact on Bermuda’s marine environment, and how to minimize that impact. It is a truly exceptional opportunity, probably the first of its kind in Bermuda, where so many various parties have come together under a common cause. Partners include the Bermuda Underwater Exploration Institute (BUEI), Ocean Support Foundation (OSF), Bermuda Zoological Society (BZS), Bermuda Aquarium Museum and Zoo (BAMZ), Department of Conservation Services, Department of Environmental Protection, Bermuda Institute of Ocean Sciences (BIOS), Bermuda Blue Halo, Bermuda Ocean Explorers, Reef Environmental Education Foundation (REEF), Bermuda Commercial Fisheries Council, Bermuda Resources Board, Bermuda Tourism Board, Groundswell, the Bermuda National Trust, Dolphin Quest, and the various dive shops such as Triangle Diving, Dive Bermuda, Bermuda Sub-Aqua Club, Blue Water Divers, Fantasea, and Tucker’s Point.
Answered by the Bermuda Underwater Exploration Institute and Corey Eddy.
Q- Does Bermuda have any current rules or regulations involving lionfish? What about the U.S. or Caribbean nations that are also affected by this fish?
Lionfish caught as bycatch by commercial fishermen in the lobster trap fishery may be sold. (Other bycatch from the traps may not be sold, so this is an example of adapting regulations to promote the capture and sale of lionfish.) Commercial fishermen can obviously sell any lionfish that they catch by standard methods. (At present, commercial fishers may not use a spear, and speared fish may not be sold.)
For licensed spearfishers, lionfish are exempt from the bag limit of 2 fish per species per day regulation. (Again, an example of adapting regulations to promote the capture of lionfish. However, recreational fishers may not sell their catch, regardless of the capture gear used.)
A regular spearfishing license does not permit the use of SCUBA or of spearing within 1 nautical mile of shore. This is why we have issued special permits for lionfish culling, with requirements for training etc. The lionfish special permit will entitle the holder to use a short (<5’) spear with a paralyser / prong tip to cull lionfish only, and permits the holder to do this on SCUBA and / or within 1 nautical mile of the shore.
Most areas in the US and the Caribbean are promoting the culling of lionfish and are using the commercial incentive of sale for consumption to drive this. Most places, particularly those where lionfish are abundant in the shallows, are emphasizing spearing, and are promoting this through derbies / tournaments and regular events. Commercial fishers may spear in many of these places and are being encouraged to target lionfish. Some places are also trapping lionfish, but these are generally jurisdictions that permit trapping for fish in general and they are not necessarily focused on lionfish.
There are some examples of what other places are doing in terms of management in the Morris manual. Here is a link to lionfish stuff from GCFI, which also has examples of what is going on in other places. I believe Florida has suspended most regulations on lionfish spearing, but I’m not sure.
Answered by the Department of Environmental Protection.
Q- What can the average, concerned non-scientist do to help?
Anyone that sees a lionfish, whether they’re fishing, diving, snorkeling, or just walking the beach, can report that to the relevant branch of their local government (e.g. Bermuda Department of Environmental Protection or US Fish and Game) or even local dive shop or bait shop. People can also go out and spear lionfish themselves. Perhaps less obvious, people can ask for lionfish at restaurants and markets, wherever they get their seafood. We really need to create a fishery for lionfish, so fishermen can fish them, hopefully too much, and start to minimize their population.
Copyright © 2013 by Marine Science Today, a publication of Marine Science Today LLC.