Top ten lionfish facts

From Death to lionfish

10 What’s with the name, lionfish?  Nobody knows for sure how they got their name, but when they spread out their pectoral fins it sort of looks like a lion’s mane.  And they are ferocious predators. The scientific name for the species is Pterois volitans (pronounced, Tare-oh-ease vol-eh-tawns). Pterois = wing or fin, from the Greek, and volitans = flying, from Latin.  Another common name for lionfish is turkeyfish!

9 The marine aquarium trade makes a ton of money selling lionfish. Indeed, some countries are considering exporting live juveniles as a way of controlling their lionfish invasions. The logic involved is seriously flawed (and ironic) as this approach can only further contribute to the problem elsewhere. Lionfish are an iconic species for hobbyists due to their spectacular beauty. They are easy to find in aquarium stores. You can order them off the web. They survive well in poor water quality, they resist diseases, and they eat just about anything. It’s probably too late to matter for lionfish, but we clearly need better controls on live shipping of non-native fish from around the world.

8 How did the INVASION start? The INVASION is most likely a result of escapes or releases from aquariums, either by accident or on purpose. There is one documented case of lionfish escaping from an aquarium located in a house damaged by Hurricane Andrew – the fish were seen swimming nearby after the storm. The “on purpose” introductions are assumed to occur from hobbyists who dumped them into canals (not knowing any better) when the fish either got too large for their aquariums or became unwanted. Genetic evidence from recent scientific results suggests multiple introductions.

7 Lionfish reproduction is sexual. Fertilization involves complex courting and mating behaviors where males will use their spines and fins in visual displays. Females produce mucus-encapsulated clusters of thousands of eggs that are fertilized by males as the clusters float in the water. Females can produce egg masses during all seasons of the year. The clusters apparently have chemicals that make them distasteful to predators. Yuck.

6 The red lionfish is a solitary ambush-predator. They use their fan-like pectoral fans to herd or corner prey against corals or ledges, then consume them whole in a single strike. They can also strike fast, sucking and gulping smaller fish into their mouths in an instant. They devour juveniles of many important commercial species, like snappers, groupers, and shrimp. Lionfish also compete with native species, starving them out through competition or by eating them!

5 Do lionfish have teeth? Yes, but they are small and are located as you might expect on the upper and lower jaws, but also in a small patch on the roof of the mouth – a good system for grasping prey that are caught by the quick predatory strikes of the species.

4 A lionfish’s stomach can expand to 30 times its normal size. They can really fill up! This ability and its voracious appetite is what makes it such a frightening INVADER in Florida, the Caribbean, and most recently in the Gulf of Mexico.

3 Where are they found in Florida, the Caribbean, and Gulf of Mexico? Bad news – from shallow mangrove waters to nearly 1000 feet deep. They are also hardy to temperature lows of about 16 °C, which means that they thrive along the southeast US as far north as North Carolina.

2 Lionfish have no known predators in the Atlantic and Caribbean. In lab studies, many native fish starve to death rather than attack a lionfish. It’s time to consider international controls on live shipments of lionfish. You can order them on the internet. How does that make sense?

1 WARNING! Lionfish can inflict a nasty, painful, agonizing sting or stab from any of their 13 dorsal, 3 anal, or 2 pelvic spines. The spines are defensive only and are not used in hunting. The potent venom is contained in venomous glandular tissue that is located in the grooves of the spines. When a spine enters a victim the tissue is torn and the venom diffuses into the wound. The venom includes a protein, a neuromuscular toxin and a neurotransmitter called acetylcholine. How people react to the stings depends on the amount of venom in the wound, the immune system of the victim, and the location of the sting.

6 Responses to “Top ten lionfish facts”

  1. talk about a fish you want to avoid…

  2. Don says:

    Hey John:
    Can you comment on this paper relative to counter claims that lionfish have no known predators in the Caribbean?

    Mumby PJ, Harborne AR, Brumbaugh DR (2011) Grouper as a Natural Biocontrol of Invasive Lionfish. PLoS ONE 6(6): e21510. doi:10.1371/journal.pone.0021510.

    Thanks, Don

    • John Bruno says:

      Yes. The Mumby et al paper (link) found that lionfish were less abundant inside a marine reserve (the Exuma Cays Land and Sea Park, where grouper are protected and relatively abundant) than on adjacent fished reefs with fewer top predators. The authors attributed this difference in lionfish density to natural predation by grouper. However, the reserve has a full time ranger that shoots and removes lionfish. Thus the findings likely had little to do with “biotic resistance”.

      We are about to submit a related paper to PLoS One based on far more sites and surveys. We found no relationship between the density or biomass of lionfish and that of top predators including sharks. Lionfish are remarkable abundant even on reefs with “intact” food webs and plentiful top predators. They may be eating lionfish, but they certainly are not controlling them.

      Take a look at these two videos I took of lionfish loitering at “Gardens of the Queen” – arguably the reef in the Caribbean with the most top predators (grouper, snapper, sharks, barracuda, eels, etc): https://vimeo.com/34401430 https://vimeo.com/29739395

  3. Michael Sweet says:

    John,
    I like you site. I hope you post some of your stuff on sea level rise at Skeptical Science.

    Lion Fish are a minor fish in the aquarium trade. While you will usually find them in any aquarium store, they turn over slowly. I dove with several commercial collectors in Fiji (I went out with Walt Smith’s men. He is the biggest collector in Fiji) and Micronesia and they did not even bother to collect lionfish. It was not worth the trouble. They sell hundreds of damsel fish for every lionfish. My local store now sells lionfish from the Florida Keys. Too few to make any difference.

    There are a lot of exotic aquarium fish established in Florida and Hawaii freshwater ponds and streams. Lionfish are the only salt water fish that I know of that has established itself.

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