The reported discovery of a Lionfish in Maltese waters has alarmed marine biologist Professor Alan Deidun, who is offering a generous reward to anyone who can hand it to him.
“It is important that we catch this fish before it colonises our waters. These fish have wrought widespread damage wherever they have been, such as the Caribbean, waters off Florida and the eastern Mediterranean. Lionfish eat most other fish while having few predators themselves,” he told Times of Malta. "We must nip its invasion in the bud."
Studies abroad have described the Lionfish as an invasive species capable of causing extinctions of native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats.
The lionfish can grow up to some 40cm and it deters predators using its poisonous spines. It releases eggs every four days all year round, producing some two million eggs a year.
A presence of the Lionfish in Maltese waters was first reported by the University’s Conservation Biology Research Group in July 2016.
Prof Deidun said another discovery of the Lionfish (Pterois sp.) in Maltese waters was reported along with a photo on Facebook in a post a few days ago. The post has since been taken down.
Two lionfish species exist in the Mediterranean – the common lionfish and the red lionfish – but it was not clear from the photo uploaded briefly which species was actually caught in Maltese waters.
Prof Deidun, who has been studying marine alien species invasions in Maltese waters for the past 15 years and coordinates the Spot the Alien Fish citizen science campaign (www.aliensmalta.eu) said he had been able to track down who was responsible for the post. He was told that the fish was disposed of, dead, although he had no certainty of this.
Unlike the silver-cheeked toadfish, a toxic species of puffer fish reported in Maltese waters in recent years, the lionfish is venomous for anyone who touches its needle-sharp dorsal, pelvic and anal fins but it is not toxic, and therefore good to eat.
It can be found in the East Mediterranean, notably around Cyprus, as well as in parts of Greece, but Prof Deidun doubted that it had moved to Malta unaided by human activity, it being a slow mover.
Rather, he feared it had been released by someone who bought it from an aquarium shop.
“I had raised the alarm when they started selling them, and they appear to have stopped doing so now,” he said.
Such was the damage they caused to the sea environment, he said, that in some regions, notably around the Caribbean and in Cyprus, people were actually paid to catch them and lionfish spearfishing competitions are regularly organised.
He is likewise offering an underwater camera worth €370 to anyone who can hand him the specimen caught in Maltese waters, which will then be stuffed to be used for educational purposes through the Spot the Alien Fish campaign (Supported by the International Ocean Institute).
Those not interested in the camera will be handed the equivalent in cash instead. The reward will also be given for useful good photos of the fish in Maltese waters.