Divers have captured more than 200 red lionfish on Cayman’s reefs since the ferocious species first invaded the local waters early last year.
Scuba divers authorised by the Department of Environment and the Marine Conservation Board have caught 233 of the fish on all three islands in the last 16 months and handed them over to the department to be destroyed.
‘We put them down when we get them; we don’t keep them alive,’ said Bradley Johnson, research officer with the Department of Environment, adding that the department keeps one live lionfish to use in demonstrations of how to catch them.
The DoE keeps the bodies of captured lionfish in its freezer, after staff have measured their length and taken DNA samples.
Since February last year, when red lionfish were first spotted in Cayman waters, scuba divers have caught 112 in Little Cayman and 108 in Grand Cayman.
Only a handful have been captured in Cayman Brac, mostly because the diving industry was so badly affected by Hurricane Paloma in November last year.
Mr. Johnson said the prevalence of lionfish found in Little Cayman was due to the amount of diving done there over a relatively small area.
‘The communication between dive crews also helps,’ he said. ‘One crew could spot the lionfish but might not have the equipment to catch it, so they radio another company and their crew can go down and get it.’
Mr. Bradley said it was illegal for anyone who has not been trained and certified to take lionfish, in accordance with the Marine Conservation Law. ‘That is why we’ve had to license divers to remove them for us and they have to turn all lionfish that they catch over to us.’
The fish are put down using a combination of one part Eugenol, or clove oil, to nine parts alcohol in sea water.
‘We just drop the fish into it. It has been described as a narcotic overdose for fish,’ said Mr. Johnson.
Cayman has been learning from the Bahamas how to deal with the invasion of lionfish.
‘They have a huge problem there,’ said Mr. Johnson. ‘The invasion of the Caribbean by lionfish started in the Bahamas. They came from the east coast of the US to the Bahamas and then into the Caribbean.’
The department has distributed special plastic nets to capture the lionfish, but many dive masters simply take Ziplock bags underwater with them to catch any lionfish they come across because they say the nets are unwieldy to take on dives.
‘Some people prefer the smaller nets or bags as they are easier to carry on a dive, and for the smaller lionfish, the bags are just as easy,’ said Mr. Johnson.
‘The nets will be more practical for the larger fish, which we are starting to get now. It’s really up to the licensed individual as to how they prefer to catch them.’
The Cayman Island Tourism Association and Bert Foster of Underwater Supply helped the DoE to bring the capture gear on island, with CITA paying for 50 nets and Mr. Foster arranging for the ordering and importation of the equipment at cost.
The DoE has purchased 10 sets of the capture gear from CITA, whose members are also buying sets from the association.
The British Sub-Aqua Club recently bought two sets from the DoE, which had donated another set to the Central Caribbean Marine Institute based in Little Cayman, Mr. Johnson said.
Despite continuing efforts by dive professionals and authorised divers to capture lionfish, it is unlikely they will be able to ever eliminate the invaders from Cayman’s reefs. The fish can lay 30,000 eggs in one spawn and they can spawn every month.
‘It’s a losing battle if the intention is to eradicate them, especially considering how well established they are in surrounding islands like Cuba and Jamaica,’ Mr. Johnson said. ‘Our intention is to remove any and all lionfish we find in Cayman waters. The more we remove, the fewer native fish will be eaten by them.’
He said all the divers can do is keep removing them from the underwater habitat and hope that native species begin to adapt to this new predator.
The red lionfish has 13 venomous spikes along its dorsal fin, as well as one in each pelvic fin and three in the anal fin. Its sting is agonisingly painful, even though it is not usually fatal to humans.
PIC: Lionfish in a ziplock bag
Caption: A lionfish captured in Little Cayman last week
Photo: By Sonita Malan