Researchers at the Central Caribbean Marine Institute have surgically tagged 21 lionfish in a unique project to track the movements of the invasive predators on Little Cayman’s reefs.
Scuba divers are tagging lionfish at depths of between 65 and 110 feet.
The process involves capturing lionfish in hand nets and surgically implanting acoustic tags in the abdomen of the fish. A bright blue external ID tag is also attached to the top of the tail before the fish is released so it can be easily identified and not accidentally speared by cullers.
It is hoped that the tags will help improve understanding of lionfish behavior and movement patterns.
Alli Candelmo, who is leading the project along with Drew Butkowski and Tom Sparke, said researchers had to perform tricky surgical work in low light at depth with limited bottom time in order to fit the tags.
“We have run into a number of obstacles during the project which have made it both exhilarating and frustrating,” Ms. Candelmo said.
“If someone had told me last year that I would be suturing up a lionfish at 95 feet in the dark while my colleague chased a nurse shark around above my head, I would have laughed, but each day in the field is a new adventure and we continue to learn and adapt.”
The implanted acoustic tags transmit data to receivers that have been placed in an array along the northeast reef wall of Little Cayman.
The data will reveal movement patterns of these lionfish for the next six months, which will allow scientists to gain insight into the vertical and horizontal migrations of the fish.
Ms. Candelmo said the project would help dictate how cullers tackle lionfish in Cayman’s waters.
If lionfish are found to move predictably between deep and relatively shallow reef habitats, she said, strategically scheduled culling efforts at recreational diving limits could be sufficient to control deep water populations and limit the need for technical diving or alternative capture methods such as traps.
“Preliminary data from the receivers have shown both horizontal and vertical movement by individual lionfish,” she said. “Some of our lionfish have been recorded quite deep. We are intrigued to see what the next six months reveals from each fish and are very excited for the outcome of this project.”
Researchers will also use the data from the study in combination with data collected from lionfish culling efforts on Little Cayman from 2011, to develop a publicly available database accessible through an interactive online map.
The map will provide information on densities and movement patterns of the Little Cayman lionfish population as well as site specific culling activity around the island, according to CCMI.