Venom with a voracious appetite - The lionfish you should eat

I'll never forget the first time I saw it in the wild. I was snorkeling off a pier in Vieques, Puerto Rico. The sunlight flickered underwater as the breeze rippled the waves. With a net in one hand, a nervous tremor disguised by the movement of the waves, I searched for a flashy fish with venomous spines and a voracious appetite. The lionfish is boldly striped and has long, spiny fins poking from almost every direction. For such a dramatic looking animal, the lionfish was proving tricky to spot. Then my boss pointed under a ledge, and there it was, hidden in plane sight in a way I thought impossible. That's the thing about the lionfish. There is nothing subtle about this species, from its appetite to how it stings to how quickly it reproduces, and yet it has a way of making itself at home in places it definitely doesn't belong. 

If you're wondering what an invasive species is, chances are you have already encountered one. An invasive species is anything that is in a land that it isn't native to that is also wreaking havoc on local plants and animals. In New England, we have the beautiful Oriental Bittersweet which strangles local plants and trees. In the south, Kudzu vines cause similar damage. If you've ever been told to wash off a boat before putting it in a reservoir, it may have been to stop the spread of the infuriating zebra mussel. The Asian longhorn beetle is the reason you can't bring firewood across state lines in New England. We are surrounded by invasive species, but in this long list of rabble rousers, the lionfish stands out.

The predominant theory as to how lionfish came to the Atlantic is that they were released from home aquariums when they got bigger than the owners expected. This is a common story. Finding Nemo may show the happy little fish who manage to escape from a tank into the ocean, but when this happens in reality, the results are quite different. Released animals usually die out in a habitat they are ill suited for, either freezing, starving, or being eaten. But every once in a while a species will find that the environment was practically designed for them to thrive. What follows is nothing less than madness. The video below shows a time lapse up until 2010, showing how quickly lionfish spread through the US and the Caribbean.

Why didn't the lionfish die out when released into an ocean where they were never meant to be? One reason is that they don't have natural predators in Atlantic waters. While sharks, groupers, and barracudas can be trained to eat lionfish and have been spotted doing so, lionfish are not their preferred food.

In addition, lionfish seem to be able to live just about anywhere. I saw lionfish in Belize less than 4 feet deep, but they have been spotted shipwrecks up to 300 feet deep. Most fish are constrained by the kind of water they can live in, but lionfish get around this. An inquisitive 12-year old girl from Florida found that lionfish can survive in water that barely has any salt in it, teaching us to never underestimate both lionfish and young girls.

So they survived, but why do they continue to spread? Have you heard the phrase "mate like rabbits?" We should change it to "mate like lionfish." While a lot of native fish can't reproduce until they are about 3-5 years old, lionfish can mate after just one year. A female lionfish is a mating machine; she can reproduce every 4 days, making a whopping 2 MILLION eggs per year! That's a lot of baby lionfish.

All those fish need something to eat, and that is where we run into problems. Lionfish are voracious feeders. When lionfish are introduced to a coral reef, they can eat 90% of the baby fish in a reef in just five weeks. No baby fish means few adult fish. This is bad for reefs, and this is bad for fishers that rely on fish for their livelihood.

The stomach contents of just one lionfish. That's 21 fish swallowed whole.
 Credit: USGS

These hungry fish are fast. Given the chance, the lionfish would eat Nemo before he knew what hit him.

There is hope, however. If there is one thing humans are great it, it is collecting astonishing numbers of fish from the ocean. Fishers are catching this fish and selling it to restaurants which sell it to hungry tourists and locals alike. The venom in the spines is neutralized by heat, so once the animal is cooked it turns out to be a tasty treat. The spines are even used to make jewelry. These aren't just cool ideas for making the best of a bad situation; these are solutions that are both making people money and having an impact.While it may be impossible to eliminate the lionfish completely from the Atlantic, keeping it in check helps local fish and local people.

So what can you do? Support these efforts. If you travel anywhere near the lionfish invasion, try the fish! It's a delicious, flaky white fish which is suitable for a wide range of dishes, from fillets to ceviches. Buy lionfish jewelry if you come across it. Continue to create a demand for this invasive species and people will continue to provide it. But also remember why we have a lionfish problem in the first place. The next time you have to wash off your boat or buy firewood a mile down the road from camp, be thankful people are doing what they can to stop invasive species.