Marine Science|Places We Visit

Lionfish: Out Of Sight, Out Of Mind

What do you see in your mind’s eye when you hear the words “coral reef”?

Is it a sea turtle gliding effortlessly above a rainbow garden of sponges and coral? Do you see schools of fish moving en-masse, seemingly aimless yet perfectly in sync? Do you see that strange fish with bars that resemble tiger stripes? Take a closer look, because that strange, striped fish is actually an invasive species causing an unseen ecological collapse. Known as the Indo-Pacific red lionfish, this species one of the most prolific marine invaders around.
The invasion of the lionfish (Pterois volitans) has been altering the delicate ecological balance of the Atlantic Ocean since the species’ introduction in 1985. In that time, the lionfish population has exploded at an exponential rate, largely due to a lack of native predators and the species’ incredible reproductive capability. Producing 30,000 eggs every 3-4 days, the lionfish has been able to wreak unchecked havoc on marine ecosystems across the region. In the United States alone, Lionfish can now be found along the entire East coast of the United States, as well as through the Gulf of Mexico. The scale of the lionfish invasion, however, reaches far beyond U.S. coastlines. As Emily Stokes, Invasive Species Specialist with the non-profit organization REEF (Reef Environmental Education Foundation), explains: “You can find lionfish pretty much anywhere, especially in the summer months, from New York all the way down to the coast of Brazil and into the Caribbean and Gulf of Mexico. They have completely inundated the region, and they’re eating all of our native fish species.”

In heavily invaded areas, lionfish have reduced native fish populations by up to 90%


    And therein lies the problem: Lionfish are decimating populations of recreationally, commercially, and ecologically important fish. Notorious for their voracious appetite, lionfish are gobbling up nearly everything that crosses their path. Scientists have found that in heavily invaded sites, native fish populations have declined by up to 90%; Larger predatory fish have even been documented actively avoiding lionfish in these sites. With a stomach capable of expanding up to 66% of its original size and the ability to consume prey up to half their size, lionfish have become the new king of the coral reef – an unrelenting predator with an insatiable appetite. The lionfish is an apex predator in disguise, establishing itself at the top of the food web wherever it swims. Their survivability spans an impressive array of environmental conditions and can be found in nearly all subtropical marine habitats: temperatures as low as 10°C; bodies of water where salinities vary wildly; shallow water and deep water habitats – you name it, the lionfish is almost unstoppable; the operative word here being “almost.”

Eat the enemy!


    One of the most common misconceptions about lionfish is that they are poisonous – a misnomer when describing animals containing toxins used for defense. The lionfish is actually a venomous creature, the difference being that poisonous organisms must be ingested in order to harm the body, whereas venomous creatures must sting or bite in order to deliver their harmful toxin. While this may sound like mostly irrelevant scientific jargon, it actually leads to an interesting realization: Lionfish are delicious.
Yes, lionfish have 18 venomous spines that, when handled improperly, can deliver a painful, non-lethal sting, but when the spines are removed and discarded, lionfish are completely harmless. Filleted, grilled, and served with cilantro and a peach-mango salsa, lionfish can hold its own with even the pickiest of seafood connoisseurs. In many places, lionfish has even become a delicacy – a highly sought after entrée that benefits an already overfished ocean. And while the lionfish is an incredible example of biological adaptability, the key to restoring the delicate balance of our oceans just might lie in having the species swim in butter rather than our coral reefs. In fact, our best shot at controlling an out-of-sight, out-of-mind ecological disaster may just be our dinner plates. As the adage goes, “We have to eat ’em to beat ’em!”

Interested in learning more about the lionfish? Check out how Florida Keys locals are rallying around Lionfish derbies to control local populations of lionfish on Florida’s coral reefs, or check out our voyages through the Caribbean!

Images courtesy of REEF, NOAA, USGS, and SportDiver