Red Lionfish
The red lionfish is a venomous, strikingly patterned reef fish native to the Indo-Pacific. Since arriving in the Atlantic in the 1980s, it has become one of the Caribbean's most aggressive invasive species — and a fixture of Utila's dive briefings.
The Invasive Threat in Utila
Red lionfish (Pterois volitans) and devil firefish (Pterois miles) are native to the Indo-Pacific. They first turned up off the Florida coast in the mid-1980s, most likely released from home aquariums, and by the 2000s had spread through the Caribbean and Gulf of Mexico. With no natural predators in the Atlantic, they feed heavily on juvenile reef fish and small invertebrates — a single lionfish can dramatically reduce the number of young fish on a reef within weeks. They also reproduce year-round and reach sexual maturity within months, letting local populations grow quickly if left unchecked. Utila's dive community responds the way most of the Caribbean does — organized culls and routine removal on every dive, which is what this page tracks.
What Reef Vision Tracks
Location & Dive Depth
Every logged encounter is associated with a dive site and the maximum depth recorded for that dive, providing a clear picture of site hotspots where lionfish concentrate and where removal efforts are paying off. Looking ahead, we aim to integrate directly with GPS-enabled dive computers and timestamped camera data to automatically map the exact depth and precise coordinates for every individual sighting.
Removal & Culling Log
Culling activity is logged dive by dive: how many fish were removed, whether egg-bearing females were among them, and how that effort is spread across sites and outings over time.
Population Trends
Aggregated across every dive, these logs give a longitudinal read on lionfish density in Utila's marine reserves — data that can help inform local conservation and removal priorities as the picture develops.
References
- NOAA Fisheries — Lionfish invasive species biology and impacts
- USGS Nonindigenous Aquatic Species database — Pterois volitans / Pterois miles
- REEF (Reef Environmental Education Foundation) — Lionfish research and derbies