NOAA Ocean Service Education banner
" "

The Lionfish Invasion!

Some Lionfish Biology

back a page next page

Profile of a lionfish showing the distinctive fleshy tentacles

Profile of a lionfish showing the distinctive fleshy tentacles above the eyes and below the mouth. Click on image for larger view and further details.

The lionfish (scientific name Pterois volitans) is a popular saltwater aquarium fish with distinctive maroon (or brown) and white stripes, fleshy tentacles above the eyes and below the mouth, and an imposing fan of prickly venomous spines. Although not fatal, the sting of a lionfish is extremely painful. Because these fish are not aggressive toward people, contact and poisoning is usually accidental. The species of lionfish now found in U.S. waters produce a mild poisoning.


Lionfish Biology Fact Sheet - Find Out More About the Biology of Lionfish!


spines of lionfish

Look, but don't touch! Although not fatal to humans, the dorsal, anal, and pelvic spines of lionfish can deliver a painful sting, as well as cause headache, vomiting, and respiratory distress. (Photo credit: Stephen Vives)

The lionfish's sharp, slender spines are located on the dorsal, anal, and pelvic fins. The venom is a combination of protein, a neuromuscular toxin, and a neurotransmitter called acetylcholine. The sting causes intense pain, redness and swelling around the wound site. Although the worst of the pain is over after an hour or two, some people report pain and tingling sensations around the wound for several days or weeks. On rare occasions, when the venom spreads to other parts of the body, people may experience headaches, chills, cramps, nausea, and even paralysis and seizures.

Lionfish are native to coral reefs in the warm, tropical waters of the South Pacific and Indian Oceans. They prey on a wide variety of smaller fishes, shrimps and crabs, and have few predators in their native range, where they occupy the upper levels of the food chain. At present, little is known about how other coral reef species in the lionfish's "adopted" environment of the Atlantic Ocean might fare against them.

Lionfish also are believed to pose high risks to the local reef communities. As a predator of both economically and ecologically important species, lionfish a capable of disrupting the balance of reef communities. Lionfish are ambush predators and may use their outstretched, fan-like pectoral fins to "corner" their prey. Scientists are concerned that lionfish could seriously reduce the numbers of prey species and/or compete with other reef predators. When a new species is introduced in an area, it can take over the niche, or role, of a native species in its ecosystem, thus squeezing it out--this process is called competition. Another important factor is that native prey species lack of experience in confronting the intimidating lionfish might make the lionfish a more effective predator.


back a page next page


Learn More: