Introducing our April Fish of the Month, the Red Lionfish, Pterois volitans! We chose this species because April is Lionfish Derby month — REEF's 17th Annual Florida Keys Lionfish Derby & Arts Festival takes place April 23–26, 2026, right here in Key Largo!
Survey Regions: Red Lionfish are native to the Indo-Pacific, but since the mid-1980s they have become one of the most impactful invasive marine species in the Western Atlantic. REEF volunteers have documented their spread throughout the Tropical Western Atlantic (TWA) survey region, including Florida, the Caribbean, and the Gulf of Mexico.
Size: Red Lionfish can grow up to about 15 in / 38 cm in length, though individuals approaching 18–19 inches have been recorded in Atlantic waters where they face few natural predators.
Identifying Features: Red Lionfish are striking and hard to miss. They have bold red, maroon, and white vertical stripes across the body and head, along with large, fan-like pectoral fins and long, separated dorsal fin spines that give them a dramatic, feathery silhouette. Fleshy tentacles extend above the eyes and below the mouth. Their 13 dorsal spines, 3 anal spines, and 2 pelvic spines are venomous — a painful defense mechanism that deters most would-be predators.
Fun Facts: Red Lionfish are voracious predators that use their fan-like pectoral fins to corner small fish and crustaceans before striking with lightning speed. They can consume prey up to half their own body length! A single female can release roughly 2 million eggs per year, spawning every few days in warm waters — a key reason their populations have exploded in the Atlantic. Because they have virtually no natural predators in the Western Atlantic, targeted removal efforts like the REEF Lionfish Derby are critical for controlling their numbers and protecting native reef ecosystems. And here’s some good news for the adventurous eater: lionfish are delicious! Their white, flaky meat is mild and buttery, and eating lionfish is one of the tastiest ways to support reef conservation. Come try some for yourself at the free Conservation Science & Arts Festival on Sunday, April 26 at the REEF Campus!
Thanks for reading, and stay tuned for our next Fish of the Month.
Photo by Daryl Duda.