Cayman Islands: Tracking Lionfish

The scientific dive team for the Academy’s expedition to the Cayman Islands included Associate Curator of Ichthyology Luiz Rocha, Steinhart Aquarium Director Bart Shepherd, and Diving Safety Officer Elliott Jessup. The team received scientific collection permits from the Cayman Islands Department of Environment.

Luiz Rocha has been studying lionfish for many years, but in the Caymans, his team dove as deep as 400 feet to collect them. By analyzing stomach contents, Rocha and colleagues will be able to determine what the invaders are feeding on (i.e. what local populations may need increased protections), and by observation, they were able to begin to asses whether local culling programs are successfully holding local lionfish populations at bay—or whether the species is escaping the cull by going deep. Though data is still being analyzed, the team was quick to note they saw more lionfish, even at great depths, than expected. 

The researchers also brought lionfish DNA samples back to their labs for a population genomics study. Determining how groups of lionfish differ from island to island in the Caribbean may provide new insights into how resources can be better used to control populations. With 40 pounds of lionfish culled during 20 hours underwater, they've got a lot of material to work with. 

Targeted removal is the only known strategy for managing lionfish numbers, so Rocha and his team are working with local governments to encourage people to eat and hunt lionfish (which, fortunately, happen to be delicious). One example of control efforts in the Cayman Islands is a diving course called “Invasive Lionfish Tracker" that teaches local and visiting divers how to safely capture and euthanize them. Other examples of culling efforts include regular fishing tournaments and The Lionfish Cookbook, which was released by Reef Environmental Education Foundation in 2010.