Hunt for the world's largest land crab

by Huw Cordey for South Pacific island giants, 1 January 2008

TV producer Huw Cordey travels to a remote speck in the South Pacific Ocean to hunt a giant. A crab so big that its pincers can carve up coconuts.

The island of Metoma is so small it isn’t mentioned by name in ‘The Times Atlas of the World’. It’s so remote that to get there, I have to take a propeller-driven Twin Otter plane to a larger, neighbouring island. Then an hour long boat journey, using petrol my production team had sent ahead weeks before.

I’ve journeyed to this distant land to film a giant, the world’s largest land crab, a crab on steroids if you like. A species that can grow to the size of a newborn baby.

Yet despite its great size, I’m unsure whether I’ll be able to film this magnificent creature gathering in huge hoards - one of the main aims of the shoot. Perversely, its gigantic size is what makes the coconut crab attractive prey for human hunters. And in recent years, too many have been taken for the pot.

Dish of the day

Landing in the Torres islands, my heart sinks. The front and rear holds that had just been filled with my film crew’s camera kit were now being loaded with baskets of coconut crabs (some were even squeezed into the foot wells inside the plane). Five hundred kilograms of crabs are exported from the region each week, according to the pilot. This trade in coconut crabs, considered a delicacy, means that its numbers have crashed across its range in the South Pacific.

Glen, a local fisheries officer who accompanies us on the trip, reassures me by saying that the crabs on our island of Metoma have been protected for twenty years. But then he admits he hasn’t actually set foot on the island for three years. And a lot of crabs can be eaten in that time.

We arrive on Metoma to a forest floor littered with broken branches, and trees missing leaves, as if some giant had shaken each by its trunk. The week before, Cyclone Funa had blown through Metoma and the wider Torres islands, part of the island nation of Vanuatu - itself a speck on the map lying to the southwest of Papua New Guinea.

If crabs could smile

Jean Pierre John - a coconut crab's best friend

Jean Pierre John, head of the only family living on Metoma, greets us with a grin. His happiness seems infectious. If coconut crabs could smile, the ones here would have grins as long as their pincers. For while their relatives elsewhere are herded up by the basket load, the crabs here are free to walk around unmolested. It’s a fact that makes Jean Pierre an impressive man.

Thirty years ago Jean Pierre feared his island’s crabs may disappear forever. Back then, pigs (brought here by humans) overran the place and with a taste for crabs they decimated the population. So he got rid of the pigs. Today, Jean Pierre continues to protect the crabs by refusing to cash in on the money crawling around his island on eight legs.

The success of his crab conservation becomes immediately obvious. Within a minute of walking from the collection of thatched huts that John Pierre’s family call home, we see a dozen large crabs – albeit bits of them as they shelter in dens under fallen trunks. Tell tale signs of shredded coconut betray their presence.

Surrounded by monsters

As we enter the battered forest, more crabs surround us. Though we can’t see them, their dens lie everywhere, from ground to canopy. So Jean Pierre shows us how to tempt them out.

He splits several coconuts and impales the sections on cut saplings. Now it’s just a question of wating till dusk, when coconut crabs are most active. The bait attracts dozens of crabs. With their strong curved legs and distinctive locomotion, it’s like a scene from War of the Worlds, albeit on a smaller scale.

As their name implies, coconut crabs are rather partial to coconuts, being one of the few animals capable of breaking into the nuts without a machete. First a crab uses its plier-like giant front pincers to remove the husk like outer coating. Then, when the seed is revealed, it slowly drives the bradawl type end of a leg into the small indent at the top of the seed, a weak spot through which a germinating coconut would grow a shoot. The whole operation can take hours but eventually the nut cracks. With its flesh revealed, the crab then uses its pincers to slice off pieces.

Eating a cow

While we watch our crabs feast, I notice a scattering of bleached bones on the forest floor. They belong to one of his cows, Jean Pierre says. The crabs didn’t kill it, a falling branch did, he says. But within two days, a thousand crabs had gathered to feast on its body. The whiff of the rotting carcass must have drawn them from across the island. Within a week, the cow had been picked clean. Eaten by a hoard of giant crabs covering an area the size of a tennis court - so many, that Jean Pierre could barely walk between them.

Jean Pierre teaches me how to pick up one of these monsters. You need a firm grip and a steady eye. Coconut crab pincers can do serious damage to human digits.

Metoma’s crabs certainly appear to be living the good life. So it seems does Jean-Pierre John’s family. So what is it that keeps them smiling? Huw Cordey goes in search of the secret of Vanuatu’s happiness.

Ellen Husain films the marine wildlife living off another of the Pacific's remote islands when she goes Turtle watching with a twist.