Richard Robinson

Is the world losing its last pristine reefs?

Just 1.5 per cent of the world’s reefs are in an undisturbed state, say scientists, and one-third are in New Caledonia, a French territory vulnerable to illegal fishing and unable to agree on a management plan for its marine park—the second largest in the world. Last month, a film crew traveled to one of the most remote reefs on the planet and discovered why conservation can’t keep up with ecosystem change.

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All night, Orion danced in the decklight above my berth—pinpricks of distant starlight in a dark sky. The yacht bucked and bridled in the Pacific swell—a speck of fibreglass on a roiling ocean. But now we’ve arrived at our destination, insofar as it is a destination at all.

The sea, moments ago sounding 2800 metres deep, has shelved rapidly to 24 metres, and the deep ocean swell has been muted to wind chop. To windward, waves pile up in a frothing parapet of whitewater, yet not a scrap of land breaks the surface… nothing but a string of foam on a borderless expanse of blue sea.

Astrolabe Reef is one of the most remote coral systems in the world; more than 150 kilometres from the mainland coast.

The bathymetric map tells another story. This is the summit of a great mountain, millennia in the making. Tectonic forces have pushed the mountain higher, and tipped it, so that only a crescent-shaped crater edge nears the surface. Then, like a flowering plant, it has grown toward the light, coral polyp piled up coral polyp until it grazes the waves.

In this respect, Astrolabe Reef is structurally similar to most coral reefs, but for a single dimension—it is more than 20 hours by boat from a population centre, a simple metric that defines the shape and fate of this entire ecosystem, and every other one like it.

We’re here to film a 360-VR documentary about pristine reef systems, understand why 20 hours matters, why some reefs flourish while others fail, and why the massive abundance of sharks found here is the one sure sign of the health of this water world.

What we discovered shocked everyone on board, rattled scientists and advocates alike, and shattered the received wisdom around the vulnerability and resilience of pristine reef systems.


At the eastern end of the reef lagoon we double back on our course with the sunlight behind us, making the cauliflower-like coral heads—bombora, or ‘bommies’— suddenly obvious, like a hundred sunken ships. Dropping anchor on a prairie of sand, we rig dive gear, pick a circle of dark water, and plunge in.

It’s like falling into a fish bowl. Some fish are the size of fridges, others the size of ice cubes. Cleaner fish swirl in a cloud over a bommie, damselfish flit through staghorn coral like paper darts through a forest. Moorish idols—a butterfly perch with a footballer’s strip of black, yellow and white—tow an extravagant white ribbon from their dorsal, twice the length of the fish.

A clown fish seeks sanctuary from within a a tangle of anemone tentacles.

In fact, so many fish, with so many colours and accessories, all living in the same place, seems ecologically excessive. Yet a closer inspection reveals that the gnashing teeth of the parrotfish bear little resemblance to the tube-like beak of the hawkfish—one mouth built like a grader, the other like tweezers. The role of each fish can be deciphered by a quick dental assessment. Sharks with teeth for tearing, wrasse built for gnawing, blennies for slurping their food like soup from the edge of the bowl.

The reef crackles with life, a sound like crushing cellophane in the hand, a thousand voices of a thousand tiny inhabitants.

If I take a deep breath, and turn my face from the world of air into the world of water, and kick and crawl and heave my way to the seafloor, I can enter a new dimension, with new rules. Gravity doesn’t work down here, instead fatter things float higher. Breathing doesn’t work either, or at least not in the same way.

On the bottom of this upside-down world, I can roll over and watch my bubbles idling upwards towards the wobbly mirror of the surface—silver in the sunlight, searing white as a rolling wave passes over. Coral bommies are scattered across the bottom like rocks in a well-tended Japanese garden. There are tiny turrets of staghorn coral, some corals that look like footballs, others like a stack of dinner plates, even orb-shaped corals that look like lobotomised brains. In some places, spongy corals sprawl across the bottom in patches of orange or blue like the scene of a paintball skirmish.

It’s like visiting a strange city, with foreign architecture and unusual rituals. Every individual has a job to do, a role to fulfil, a pattern of activity that provides for the whole system.

Spend enough time down here, and the world above seems less real, even bland by comparison. Pop to the surface for a breath, and heart and mind yearn for the deep again, even as the body still heaves in air.

Even now, writing this piece at a kitchen table some 2000 kilometres distant, I feel the quiet tug of that arc of coral, like a spell has been cast that is not easily undone. Not that it needs me. In fact, quite the opposite—Astrolabe Reef would be better off if it never saw another human again.


Laurent Vigliola stares into the rollicking waves and discloses his secret fear, “Every time I come here I get really nervous. I worry that it won’t be the same as last time. That the boats might have come and taken everything away.”

He’s feared the boats arriving at Astrolabe since his first dive here five years ago—fishing boats, legal and illegal alike, could clean out a reef like this in a matter of days.

Vigliola, a French reef ecologist, has held down one of marine biology’s most enviable jobs for two decades. He has been studying pristine reef systems across the Pacific—always remote, always resplendent, always warm and tropical. In fact his work has demonstrated that the further a reef is located from a population centre, the better condition it is likely to be in. At 240 nautical miles from Noumea, Astrolabe is categorised as a ‘pristine reef’—a perfectly intact ecosystem supporting the full catalogue of species an ecologist might expect of habitat that has been spared the worst of human interference.

Laurent Vigliola has studied pristine reef systems across the Pacific. Astrolabe Reef was among the most pristine.

“A reef is like a city. It has bakers and builders and people to look after electricity supply and transportation; lots of people filling lots of roles, everything a city needs to function properly,” say Vigliola. “Scientists call this functional diversity—there are enough species to perform all the roles necessary for a functioning ecosystem.

“Sometimes when those roles are not filled, there are other species that can fill them. But the closer to people we go, the more functions disappear, and at some point, it doesn’t work like a coral reef works any more. It doesn’t even look like a coral reef.”

It’s the top of the pyramid that fails first, he says. Larger fish are more frequently targeted by fishers, they need more space to survive, and they breed very slowly—a “triple vulnerability” that puts them at the most risk.


While the mechanisms of reef failure are not well understood, the pattern of ‘trophic downgrading’ is broadly similar across many ecosystems. When the sharks and other apex reef predators are fished out, meso-predators explode in number, dramatically reducing the population of herbivores that feast on algae growing on the reef. Algae blooms, and the balance of the reef is up-ended. In time, the coral dies, the habitat collapses, and the fish life disappears.

Vigliola’s pristine reef study focused on the presence of apex predators, especially sharks, as the leading motif of a reef system that most likely has all of its constituent parts.

The results painted a concerning picture. Just 1.5 per cent of Earth’s coral reefs appeared to be in an unaltered state, and all reefs within 20 hours of human settlement were failing in some way. Reefs in his study that were closer to settlements had just 40 per cent of the functional diversity that occurs in pristine systems, 60 per cent of the total biomass and 10 per cent of sharks and other predators. Most worryingly, 58 per cent of the world’s reefs are located within 30 minutes of a population centre.

Vigliola shows me a graph on his laptop, his finger tracing a perfect curve along the axis from the most remote and healthy ecosystems, to the closest and most damaged—an arc that suggests an undeniable conclusion: human activity is bad for reefs.

But the vector of influence is less clear. Fishing is the first and most damaging activity by far, but it’s not the only one. Pollution also exacts a toll, particularly in systems where cities and reefs share a lagoon—like New Caledonia. So too does climate change; the malevolent fingers of ocean acidification, ocean warming and increased storm intensity fail to discriminate between countries.

By an unusual stroke of geography, New Caledonia is home to one-third of the world’s pristine reef systems, and three among them appear to have some of the highest biomass of any coral reef system on the planet. There is a lot at stake in this small archipelago.

Like many island nations, New Caledonia has claimed an Exclusive Economic Zone 200 nautical miles from its extremities. It has been ratified by government as the Coral Sea Natural Park, though exactly what that means remains unclear. The committee that is tasked with deciding the terms of the park management has been discussing it for three years—it took a year to decide who would be on the committee, and two years to produce a draft management plan, and even that is short of supporters.

“The draft management plan is very generic, with no specific reference to our park,” says Christophe Chevillon, director of Pew Charitable Trust for New Caledonia and a member of the management committee. “Honestly, you can find management plans like this on the internet—it’s insignificant. There are some general goals, but none of them will result in any action.”

The process has involved people from industry, government, the Kanak indigenous people, NGOs, and has been led by Maritime Affairs, a department of government responsible for managing fishing interests.

“We have 32 stakeholders, and need to agree by consensus. It’s difficult,” says Christophe Fonfreyde, deputy head of New Caledonia’s Marine Affairs Division. “Some people are saying, ‘We have to be quick,’ but there is a lot of work to do, it needs a lot of discussion, we need a lot of time… that’s the Pacific way.”

Chevillon is one of the voices of urgency. “We have one of the biggest parks in the world, but it doesn’t have any protection at all. It’s not acceptable, because we have very important species inside the park, very rare and vulnerable species, and these pristine reefs can be degraded very quickly.

“Maritime Affairs has always pitched marine protected areas against fishing interests. But this is totally incorrect. It’s the fishermen that stand to benefit from marine protected areas. If they want to fish sustainably for many years, they need large protected areas that will secure the future of migratory species and large species.”

The aptly named brain coral hunkers down on the reef platform amid a swarm of goldlined emperor and surgeonfish. In the foreground, algae shrouds dead coral, the feedstock for herbivorous fishes in the ecosystem. If large fish—usually predators—are removed by fishers, meso-predators bloom in number and lead to a decline in herbivorous fish that tend the coral garden. Algae growth blooms unchecked, suffocating healthy coral, and the reef dies.
Healthy coral is literally the bedrock of reef ecology, but it is vulnerable to pollution, warming seas, ocean acidification and less directly by trophic cascade due to over-fishing.

On April 23 this year, the deadline for presenting the draft plan to government expired, and the silence since has been deafening. The marine park is marooned in a political no-man’s land between election cycles, the pristine reefs of New Caledonia exposed to exploitation, and Laurent Vigliola’s greatest fears alive and well.

Right now, there’s nothing to stop one of New Caledonia’s 17 licensed fishing boats dropping its nets off the mouth of the lagoon and destroying this reef forever.

Nor may the invisible boundary of New Caledonia’s Exclusive Economic Zone long hold back the fleets of ‘blue boats’ from China and Vietnam exploiting the waters of Vanuatu where cheap licenses have seen an explosion of fishing activity since those nations began selling licenses to foreign vessels in 2015.

“All our neighbours are doing that,” says Chevillon. “If our government decides to open waters to foreign fishing boats, there is zero protection in the park. They will come in their hundreds and take everything.”

He isn’t guessing. Check out the animation of AIS radar-signature data from fishing vessels on Global Fishing Watch—zoom in on the south-west Pacific, pull the slider back to 2015 and watch the screen turn white as fishing boats bloom like bacteria within Vanuatu’s EEZ, until there isn’t a scrap of sea that hasn’t been trawled, right to the edges of the zone’s boundaries.

Outside of Vanuatu there is less activity, but AIS beacons twinkle across the entire Pacific, no swathe of sea is safe, not even the most remote. You can see small plumes of fishing effort in the waters of New Caledonia, sparkling bright around the Loyalty Islands, even Astrolabe Reef.

The truth is, 20 hours is no longer far enough to guarantee protection. Legislation is required, action is required, from a management committee that has failed to summon either for three years. But change is in the wind.

On May 7, Emmanuel Macron won a decisive victory in the French presidential election, forcing a change of government that has repercussions half a world away in France’s Pacific dependency. For New Caledonia it will mean a new High Commissioner, a change of guard in the Maritime Affairs administration, and potentially a more supportive attitude towards marine conservation.

Chevillon is elated. “There is global momentum now. People are beginning to realise that large marine protected areas are an effective, low-cost way to protect the oceans and make fisheries sustainable long-term. My wish is that the fishermen here understand that marine protected areas are important for everyone, including them.”


Three days into the expedition, and we haven’t seen a single shark. Vigliola’s face is drawn, like he’s been robbed. The dive sites we’ve visited, where his meticulous spreadsheets recorded whole families of Napoleon wrasse on a previous visit in 2012, turn up just one. Where he had seen seven sharks, we see none.

“You know, I’m really fearing the worst,” he says. “But we haven’t seen outside the reef yet.”

It’s true—for days we have been weather-bound in the lee of the great sickle of coral, the howling wind casting breakers over the reef platform.

The lack of predators lasts another two days, the ecologist growing quieter as time ticks away, his observations departing further and further from his 2012 data. I swear he’s changing colour—going pale as the rest of us adopt a tan.

“This is not a big reef,” he says. “One boat, two days fishing, that’s all it would take.”

Could it be that New Caledonia, a territory with the world’s second-largest marine park, within which lie a third of the world’s remaining pristine reefs, could have those reefs plundered by illegal fishers without realising? Could it be, that while the management committee were drafting a plan (that would never get submitted), that the reefs they intended to protect were dying without any of the officials noticing? Could it be that while advocates delighted in new opportunities for legislative change, that the moment to save these precious sites had already passed? How could it be, that with all this official activity and attention from authorities, that a film crew from New Zealand were the first to discover that the crown jewels had already been stolen?

A solitary grey reef shark—the only such predator seen of a 48-minute dive, patrols the wall at Astrolabe Reef. Just five years ago, divers might have encountered dozens in the same period.

Day six, the breeze abates. We manoeuvre the boat through coral bommies to the edge of the reef, where the coral platform is exposed to the full force of the prevailing easterly, hissing and heaving in the swell. Here, the reef falls away like a sheer cliff, festooned with coloured corals and bristling with life.

Vigliola slips into the sea, and bursts out again within seconds, his eyes filling his mask.

“Sharks! Six reef sharks, and a silver-tip in deeper water!” He chortles through his snorkel, overjoyed, as he scans the reef wall again. His face is painted with relief.

“They’re here,” he says, “This is the real Astrolabe. This is what I was telling you…”

The jubilation, however, is short-lived. Sharks are seen, there’s no doubt, but the abundance and behaviour are different from sightings in 2012. Vigliola brings up a previous video survey on his laptop. Sharks swarm and writhe around a baited camera—nine sharks in a frame—they approach the camera directly and hit it hard. Many of the sharks are large, so large that one attempts to swallow the whole rig.

Our 360 video, 20 Hours to Sharkland, plays alongside. We used the same burley, laid in the same location by the same scientist, and recorded a 360-degree field of view, yet we saw no more than two sharks at a time, in two hours. They approached cautiously, turning circles around the camera before disappearing into the backscatter. Just one approached the bait. Vigliola’s face falls slack again.


He confers with colleagues who have studied the reef recently, and filters through his own records from 2014. A collaborating scientist had surveyed Astrolabe in November last year and found it in a pristine state, with “sharks, Queensland grouper, and Napoleons on 80 percent dives”, though noted that it had been “emptied of bêche-de-mer”—the flaccid sea cucumbers used in Asian cuisine which which fetch US$2000 per kilogram.

In the nine months to March this year, the French Navy discovered and warned 55 Vietnamese ‘blue boats’ fishing illegally in New Caledonian waters. Five others were detained, their captains now serving eight to ten months in jail, 30 fishermen had been deported.

Vigliola estimates that Astrolabe must have been exploited by blue boats some time between December 2016 and May 2017… though he can’t be sure, not until he’s returned with a scientific team to do a full survey of the reef. Last year, Ecology Letters published a paper by one of Vigliola’s students in which they calculated that 1.5 percent of world’s reefs were in a pristine state. That figure, he admits, is already out of date.

“A few fishers probably made money at Astrolabe this year,” Vigliola wrote to me in an email after he had crunched the numbers. “Today, I suffer because I have the feeling that my kids will never see the pristine Astrolabe. It is probably gone. It’ll take half a century for it to come back if we work hard and protect what is left.”

The email had a resigned tone. He referred to Petri, a remote reef north of Astrolabe, and an anecdotal report from a colleague that it was in a diminished state too. He feared, also, that the volcanic reefs of Matthew, Hunter and Walpole to the south may have suffered the scourge of the blue boats. Only Chesterfield, on the Australian side of New Caledonia “still has a chance”, he wrote.

“I hope we can be smarter and protect the few remaining pristine reefs before they are fished. If we don’t act now, all will be gone very soon.”

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