Alexander Montarsolo spent hours this winter swimming in the cold, hunting for lionfish.

In January alone he nabbed 82. It is likely the 16-year-old has caught and given away hundreds over the past few years.

His hope is to raise awareness. An invasive species with no natural predators, lionfish feed on small crustaceans and other fish and are considered one of the most serious threats to the coral reef system. What also makes them dangerous is that they are venomous and reproduce faster than other fish.

“It all kind of started a few years ago,” Alexander said. “I was lobster diving with my dad Anthony and we just started seeing more and more lionfish and less and less lobsters.”

Concerned by the rise, the Warwick Academy student decided to do something about it.

“It took us a couple years but eventually we started to get it down. We got pretty good at catching them and learning where they hide and all that.”

Greater opportunity for practice came last May, with the end of shelter-in-place. Being on the reef was a “great way to social distance”.

Confident by January, Alexander placed third in the seventh annual Winter Lionfish Derby thanks to the 82 lionfish he captured.

“They tend to live in very similar places as the lobsters so you just go and look under the reef – under the edges and in the holes – and they’re just sitting there. A lot of the time they hardly move at all. They don’t see you as a threat,” he said.

“We were finding that a lot of the lionfish on South Shore, towards the end of the tournament, they’d obviously seen people and were very wary of people so they seemed to take right off. But the ones that we were getting on the boat, they don’t see you as a threat at all. They literally just sit there.”

The teenager typically catches between one and 20 fish at a time. He has had luck off all the beaches along the South Shore in Warwick.

“They tend to come out at dusk and dawn to feed. So normally when we’re going out on South Shore we go out around the evening time, when the sun starts to set and we’ll see them start to come out of their holes.

“But you can see them during the day – they’re just harder to spot. You’ve got to swim down and look in their holes. Sometimes we go right off the beach and get them almost immediately when we get in the water and sometimes we’re swimming for hours and hours and hardly see any.”

As he walks out of the water he will often take the time to explain to curious bystanders why he bothers: “They have no natural predators and they’re reproducing uncontrollably. They’re eating way more fish than they need to survive. They can’t stop; they don’t know when to stop. It’s not in their DNA to stop eating.

“And just like any other invasive species they’re taking over. My thought is: if I can do something that I’m all right at, to help the reef ecosystem and help the lionfish be a little less prevalent on the reef … and I feel great doing it.”

He continued: “A lot of people say I’ve heard about these things but I don’t want to eat them because they’re venomous, they poisonous and [we try to explain that they can still be eaten].”

According to Alexander, filleting the fish is easy once the spines have been taken off and cooking them is simple.

“We tell people they can cook them however they want. They’re just like any other fish. We’ve got a few different recipes that we like to do. My uncle Marco suggested that we do [what he calls] lionfish Montarsolo, which is just an adaptation of codfish mantecato which comes from Genoa and Liguria in Italy where my grandfather’s originally from.

“It’s basically just a lionfish cake with some herbs and stuff in it. It’s quite good however it takes a lot of work to do that so most of the time we just fry it up in a bit of oil, pan-fry it and have it in a sandwich or have it for dinner.”

Eager to share, he has passed on fillets to “friends and family and people around our neighbourhood”.

“We decided, ‘Why don’t we give them away and try and create awareness and break down some of the stigmas? Hopefully we can grow the market for lionfish and hopefully people will want more.”

The plan has worked so far. Most people they’ve shared the fish with have come back asking for seconds.

The experience has fuelled thoughts that a career linked to the environment might be in his future.

“I’m currently studying BTEC, business and entrepreneurship at school and also environmental systems and societies which talks about relations of humans and the ecosystems,” Alexander said.

“I think it’d be pretty interesting to find some sort of career where business meets the environment [although] I’m not exactly sure what.”

The next lionfish competition is the Spring Splash Tournament on April 15 to 17. Registration is now open at Makin’ Waves. Admission is $20. For more information on Bermuda’s lionfish follow the Bermuda Lionfish Culling Program or visit the Bermuda Lionfish Task Force website