Battle Stations…Havannah’s Thorny Army

After noticing a spike in numbers, three passionate divers on Vanuatu’s Efaté island have declared war on the menacing crown of thorns starfish which has caused havoc on the reefs of the world. With help from the local Fisheries department, a simple means of eradication is under way writes Tony Wilson.

January 31, 2019
Rebecca Murphy

Rebecca Murphy

January 31, 2019

It is the classic David versus Goliath tale.

It involves three good mates – an accountant, a builder and a retiree.

Their unbreakable common bond is their insatiable love of diving and all things related to the ocean – in this case the one surrounding the island of Efaté, home to Port Vila the capital of Vanuatu.

Their lives are based in and around the pristine waters of the mighty Havannah Harbour in north-west Efaté and through that love they have become engaged in a major battle against a marine monster that is the scourge of the Pacific.

Their sworn enemy is the Crown of Thorns starfish (COTs) or Acanthaster planci, which are large, multiple-armed starfish that usually prey on hard or stony coral polyps. The crown-of-thorns starfish received its name from its venomous thorn-like spines that cover its upper surface, resembling the biblical crown of thorns.

COTs gained international infamy in their ferocious attack on Australia’s Great Barrier Reef, one of the world’s most revered natural wonders. And that battle is still being fought.

Sadly, Vanuatu is not immune from this formidable predator, but the ongoing war against it in Havannah Harbour is one to please the ‘David’ supporters around the world.

John Warmington, a well-respected Australian-born accountant with his firm The Bottom Line, lives and breathes diving and underwater photography.

Living at Havannah Estate with is partner Sandy, he dives at least once a week in that marine paradise. And while doing that in March this year he spotted trouble.

John was diving with neighbours Dean Greaney, a popular Kiwi builder and Brian Smith, a super fit retiree and ex-Gold Coast businessman. All three are very experienced divers.

“Brian, Dean and I dive every weekend and we first noticed an outbreak of COTs off our property at Havannah Estate earlier this year,’’ said John.

“I have been a regular diver in Havannah for more than six years and I had never seen more than two or three COTs together before.

“The next time we went out it was just as bad again and we knew we had a problem on our hands.”

John went and saw Mike Crawford, the boss of Big Blue Diving in Port Vila, which is the largest dive training establishment in Vanuatu.

“They had been battling COTs in Mele Bay for some time and he told me about these injector kits you can get from Fisheries which uses two shots of 10ml each of vinegar to kill the COT,’’ he said.

“So I went to Fisheries and they were extremely helpful and I left there armed with two injector kits and a supply of vinegar.”

The injector kit is like a hand-held gun that delivers a measured dose of vinegar through a needle into the COT. It is attached to a plastic bottle filled with vinegar that floats behind the snorkeller or diver.

John said they have found COTS around Havannah waters over the past few months, in the shallows around a metre deep and down to as deep as below 30 metres.

At first the COT terminators were turning over the COTS after injecting them, but John spoke to a Noumea marine scientist who advised him to leave the COTs where they lay in case they released eggs.

The COTs can release as many as one million eggs per year, which makes them a formidable enemy.

John began emailing the Havannah community which now numbers more than 40 homes and he said the response has been fantastic.

“Not everyone can dive or snorkel or even kill another living creature despite the menace COTs are, but most of the community even those who don’t live permanently in Vanuatu, have pledged their help,” he said.

“Those that aren’t taking up the battle in the water have offered money to buy litres and litres of vinegar and some more injection kits.

“Ultimately we would like to have a kit in every home, so where possible they can defend the areas off their own beaches.”

COT War 11

The three diving buddies began COT War II around April and by August the numbers had risen to 11, which included three local ni Van villagers.

“We need more ni Vans involved as we are fighting to protect their reefs – and healthy reefs mean healthy fish around them which is important,’’ said John.

One of the original trio, Dean Greaney was an anti-COT combatant in COT War I in 2014.

“This was similar situation with numbers of COTs further south than this time – mainly between Mangaliliu and Paul’s Rock and the group involved basically decided we would not let the COTs past a certain line,’’ he recalled.

“We were pretty successful then and we are determined to win again.”

John said that recently in Havannah they had found COTs cut in two, presumably by a bush knife.

“This is the ni Vanuatu trying to help, but they do not realise that when they do that it doesn’t kill the COT, they just reform into two new starfish,” he said.

“We have asked Fisheries to help us with this and they are going to come out to the villages and talk to the people about COTs, the damage they can do and how to get rid of them, which will be a great help.”

John Warmington said it was important that tourists, divers and snorkellers received the right message from his fight.

“COTs are a Pacific-wide problem and, while they are hard to totally eradicate, they can be beaten back and there are still plenty of wonderful places in Havannah Harbour to dive and snorkel the brilliant, world class reefs,” he said.

“And that goes for all of Vanuatu as well.’’

Subscribe to our Newsletter

Pacific Island Living