Screenwriter films open water kill, scientists debate significance
Researchers in Little Cayman believe they have captured the first-ever video recording of a predator killing and eating a lionfish in the wild.
The video, recorded by Hollywood screenwriter and producer James V. Hart of the nonprofit organization Lionfish University, shows a grouper that appears to be herding the lionfish away from the safety of the reef and into open water before making the kill.
The recording is a potentially significant development in the fight against the invasive species. Lionfish populations have exploded on Caribbean reefs, threatening the entire marine ecosystem because of their voracious appetite for juvenile reef fish.
They have no natural predators in the Atlantic, and until now organized cull programs have been the only way to keep numbers down.
The video, filmed in Little Cayman, suggests that marine predators in the Caribbean could be adapting and learning to prey on lionfish. However, initial scientific opinion is divided, and both Mr. Hart and Stacy Frank, the founders of Lionfish University, caution that a single incident recorded on camera does not necessarily indicate a wider trend. It is also unclear if the grouper suffered any ill effects from consuming the lionfish.
Grouper and snapper have previously only been observed eating lionfish that had been speared by divers.
Bradley Johnson, research officer for the Department of Environment, said the video was one of the first he had seen of this type of interaction. Previous recordings have shown moray eels pursuing lionfish, without making a successful kill.
He said it was possible that the grouper in the video had been conditioned by previous interactions with divers. He also said it was unclear whether predators would learn to pursue lionfish anyway, without the influence of cullers.
Mr. Johnson believes the prospect of predators taking lionfish naturally would be a game changer in the fight against the invasion. But he cautions that while the video provides compelling food for thought, it does not amount to proof of this.
“Since the very first lionfish culling course back in March 2009, we’ve always maintained that the culling program was necessary ‘until a natural predator developed.’ The biggest unknown is when this will happen and on a large enough scale to be effective,” he said.
The Little Cayman-based Central Caribbean Marine Institute has previously reported evidence of unspeared lionfish being found by fishermen in the stomachs of grouper and snapper, further proof that some predators are adapting to pursue lionfish.
Mr. Hart, who penned the screenplays to “Hook” and “Dracula,” and first got involved with lionfish research with a view to writing a disaster movie, said he had become engrossed in the more interesting real-life story of the damage being done to marine ecosystems by the invasive species.
He became involved with Lionfish University in 2012 to raise awareness about the threat.
He said filming the interaction between the grouper and the lionfish was among the most exhilarating experiences of his career.
“This is the best production I have been involved with,” he said. “I was breathless when I came up to the surface. I couldn’t believe what I had witnessed.”
Both Mr. Hart and Ms. Frank say they have never seen natural predation on lionfish before.
They have sent the video to scientists and researchers across the Caribbean and in Florida.
“We believe the recording is historic, but the significance, from a scientific point of view is not really clear at this stage,” said Ms. Frank.
The recording leaves several unanswered question. Was the kill an anomaly? Did the presence of the diver influence the grouper? Did the grouper suffer any consequences from the encounter?
The “million dollar question,” according to Mr. Johnson, is whether this type of interaction would have happened on a reef that is not regularly visited by scuba divers.
Mr. Hart agreed that it was uncertain whether human intervention from regular cullers on the site had helped condition the grouper.
“If human interaction on the reef has helped, I don’t see how that can be a bad thing,” he said.
Ms. Frank added, “Hopefully this video is a sign that this type of behavior is starting to occur. Time will tell.”
View the video with this story on the Cayman Compass website at www.caycompass.com.
Anyone who has recorded similar interactions in the past is asked to contact [email protected].