A Nassau grouper preying on and eating a lionfish off Little Cayman was captured on camera for probably the first time, according to Hollywood screenwriter and producer James Hart of the non-profit organisation Lionfish University.

The recording, made by Hart, has made the news across the Caribbean and in Morth America.

The Cayman Compass described the successful filming as a “potentially significant development in the fight against the invasive species”.

However, the hope that groupers see lionfish as a food source may not be the answer to Bermuda’s own invasion of lionfish, says Chris Flook, the former marine species collector for the Aquarium.

He explained Bermuda’s dominant grouper species is the black grouper and that its “behaviour is quite different from the Nassau grouper,” adding that the black grouper’s hunting behaviour is a little more stealthy and wary than its cousin.

“The Nassau grouper’s behaviour makes the lionfish bolt, which is exactly what they want them to do.

“In Bermuda, we have the red grouper as well, which is closer to the Nassau grouper — but the black grouper is dominant.”

Mr Flook noted: “The Cayman Islands has a very successful management plan for the Nassau groupers, which is why they have so many there. We were seeing 3,000 to 4,000 in a single spawning aggregation. Here we’re lucky if we see one or two.

“In Cayman, the population has become so large that the competition is so fierce that there is a higher probability that lionfish will be taken as prey, even though it is not their top choice.

“They’d rather eat parrot fish because it is a softer fish, but if they are forced to do it, they will.”

Bermuda’s population of groupers is much lower than in the Cayman Islands. He explained that the local population of Nassau groupers was decimated during the years that fish pots were used as a method of catching fish. “All the fingers are pointed at the fish pot. Old photographs show decks of boats covered with Nassau groupers,” he said.

“The spawning population’s aggregations are so important to leave alone, it allows the base population to be strong enough to supply the base population and handle the pressures from fishing. Rebuilding the population from these very low levels is a daunting task that is going to take everyone’s support and commitment.”

Mr Flook said that he had worked with the grouper population in Little Cayman, and had hand-fed lionfish to the groupers there. “The sheer numbers of the groupers on the reef are staggering. When you get to the spots where they are spawning, there are so many in one spot that they get into the nets to get at the lionfish we are holding in them.”

At the end of the video, it poses a question for observers of the lionfish, explaining that some people believe it shows the Nassau grouper herding the lionfish to the surface where it then attacks and eats it. Other people feel it shows the grouper following the fish into open water before it goes in for the kill.

Mr Flook explained: “Mostly, during the day, the lionfish is sitting in a hole.” He said the Nassau grouper may nudge the lionfish to see if he can get him to move.

When a lionfish starts to move, the grouper will follow him. “The Nassau grouper is like a cat — he’ll watch it, and then pounce.

“The lionfish in the video went into mid-water, and the grouper took an opportunity,” he said.

Mr Flook said while he has seen grouper eat lionfish that they have been fed from a spear or from a net, he has not seen the behaviour captured on the video himself.

In the Bahamas, feeding lionfish to sharks has also been tried. “The sharks would spit it out.

Other sharks, further down the reef, would swallow it.

“Their spikes are hard to swallow,” he said.