Into the lion’s den: Feeding behavior and territorial range of Pterois volitans on 3 reefs near El Porvenir, Guna Yala

Andrew Harwell, SIT Study Abroad

Panama: Tropical Ecology, Marine Ecosystems, and Biodiversity Conservation


Pterois volitans, or the red lionfish, is an invasive species that has proliferated throughout Atlantic and Caribbean waters of the Americas within the last 3 decades. Because of their numerous venomous spines, these fish face little predation on the reefs they colonize, and few fish in the Atlantic are equipped to eat them without consequence. This study aims to investigate the activity, den preference, territorial range, and feeding behavior of lionfish on 3 reefs around El Porvenir, Guna Yala. Since the only way to keep lionfish populations low is to remove them from the reef by hand, it is important to know when lionfish are active and where they will most likely be found. Furthermore, an understanding of P. volitans hunting range is vital for estimating the potential damage that a population can cause to a reef ecosystem. In this study, 8 lionfish were monitored for a total of 8 hours each over the course of 2 weeks. Throughout the observation period, den sites were marked and lionfish were identified by size. This information was later used to keep track of each lionfish’s behavior and observe their hunting range. Lionfish moved an average of 2.52m away from their den sites while hunting on all reefs. The data from this research confirms existing studies which have shown that lionfish are primarily crepuscular and eat during dawn and dusk. This study also found that lionfish prefer to maintain dens, and that they typically do not travel far from these to hunt. The peak times for finding lionfish within their dens is 11am-12pm. They can, however, keep several dens, sometimes over great distances, and this expands their hunting radius far beyond their immediate territory. More research is needed to understand how this invasive species can spread throughout larger reefs.