08 May 2006, Rome - Until recently, Tuvalu’s biggest headache was disappearing under the sea.

(Rising seas due to global warming could wipe Tuvalu, one of the world’s smallest and most remote nations, off the map in the next few decades, according to some scientists. The nine tiny islands in the Polynesian coral archipelago are pancake flat, no more than five metres above sea level at their highest point.)

Then another terrifying menace struck...

Rats.

Rattus rattus, or black rats, are rampaging through Tuvalu’s atolls and gnawing through the country’s chief export crop – coconuts.

Coconuts and copra (dried coconut flesh from which coconut oil is made) are the islanders' main source of revenue. That and royalties from leasing out the country’s internet domain suffix – .tv – to an American webhosting company for a reported 50 million dollars.

The rats are particularly fond of young green nuts and very fit. Rattus rattus can leap a metre in the air from a standstill and think nothing of jumping from tree to tree without the aid of lianas. Damage to the green nuts is put at over 60 percent.

Thanks to the United Nations Food and Agriculture Organization, however, Tuvalu’s population of 9 000 can soon begin to relax – about the rats if not about the rising ocean. FAO has stepped in with a US$ 200 000 ecologically-based pest management project due to downsize the marauding rat packs.

Godzilla crabs

The programme will be implemented by a locally-recruited retired rodent management expert who will show coconut farmers how to dispose of the rats in an environmentally-friendly manner. An absolute priority is to safeguard the native population of young coconut crabs – a fast-vanishing species that is one of the wonders of the animal world.

Coconut crabs, also known as Robber Crabs – and sometimes nicknamed Godzillas Crabs – are normally the size of small cats but can grow to 80 cm in size. The world’s largest land invertebrates, their huge claws are powerful enough to lift rocks weighting almost 30 kg.

As their name indicates their preferred food is coconuts, although – unlike the rats – they normally wait for the fruit to fall from the tree before tucking in. Sometimes, however, they will carry a coconut up a tree and drop it to the ground from up to four metres – then climb back down for dinner.

The FAO programme will use recycled Australian pineapple cans containing suitably tasty baits treated with rodenticide. The cans will be strategically hung from wires to put them out of the reach of the young crabs – though not of the more agile Rattus rattus.