At first glance it's paradise, a small Caribbean island with palm trees swaying in the breeze, white sands and emerald waters, untouched by mass tourism. But Old Providence has a guilty secret - the huge number of people who have turned to drug-running and then disappeared.

On Old Providence nobody rushes. Nobody looks stressed. They never stop smiling.

It's a tiny island, colonised by British Puritans in 1629, and used as a base by British privateers, including Capt Henry Morgan, as they attacked Spanish shipping and trading centres in the New World.

Although Old Providence has long been part of Colombia, and lies close to the coast of Nicaragua, the mother tongue remains a form of broken English.

The islanders, who number between 5,000 and 6,000, feel more Caribbean than they do Colombian. Many are Rastafarians, and for a long time the place remained untouched by Colombia's violent narcotraffickers. You don't see guns or hitmen, there are no bodyguards, or the bling typical of drug lords.

The problem is below the surface, but no less serious for that.

"We are losing our men," one islander told me, asking to remain anonymous.

"According to my research, there are at least 800 men that are imprisoned in different jails abroad or have simply disappeared."

That means more than one in four of the island's menfolk have gone, if this research is correct, and the island's population divides equally into men and women. There are no official figures.

The fact is that Old Providence couldn't remain immune to Colombia's problems forever, and a few years ago, drug smugglers discovered the islanders were excellent mariners, with invaluable knowledge of the surrounding waters inherited from their privateering forebears.

"They are the last rung of the drug trafficking trade," says veteran journalist Amparo Ponton, who has lived on the island for 25 years.

"Islanders read the ocean better than anyone, so they are hired as pilots in the narco-speedboats."

If they successfully deliver a boatload of drugs to the intended destination - which may be anywhere from Honduras to Florida - they make thousands of dollars.

If they get caught they end up in jail.

Things get awkward when a boat is chased by the coastguard. In that case the crew throws the drugs overboard - and then has to explain this to the drug lords. The next job they are asked to do is one they cannot refuse.

"My boy ended up in a jail in Mississippi, USA," one mother told me.

"He had already served a six-year sentence in the United States. But he tried again and failed again.

"I think he tried again because he didn't find any work...

"Most families on the island have been affected by this one way or the other. We are losing our boys."

One way of creating more jobs would be to develop tourism, but this is a path Old Providence has deliberately shunned - in contrast with its neighbour, San Andres, which is now dotted with resorts.

But the researcher who calculates that 800 islanders have disappeared says the lack of opportunities is only one part of the problem.

"There is also a lot of juvenile adrenaline at play," she says. She has often overheard youngsters say: "I've got three options - hit, miss or get." In other words, you score, you get arrested, or you get killed.

"We have already lost 10% of the generation before mine," says 26-year-old fisherman Loreno Bent.

"There are children who wake up daily not knowing their father because he was lost in the high seas when the child was a four-month-old baby.

"Mothers are crying because their boys left and never returned. Nobody knows where they are. They could be in a jail anywhere in the world. We simply don't know."

Image caption Loreno Bent: It's not easy money

But he doesn't criticise those who run drugs.

"The sea is our economy, it doesn't matter if it's legal or illegal," he says. "What matters here is that acquiring your money hasn't involved a crime against another human. In Colombia it's considered illegal, but to many of us it's our sole subsistence. So we don't see it as something illegal."

He adds: "People say this is easy money, but no - it's the hardest type to obtain. If you wake up in the morning knowing you're putting your life in danger, then it can't be easy money."

When a son disappears, parents often do not know where he has gone, or if he will return - many seem to feel too ashamed about the crime to make a concerted effort to find out. The number of such inquiries from Old Providence is extremely low, according to Colombia's consul in the US.

But that doesn't mean the absence is not deeply felt.

"There are families," says journalist Amparo Ponton, "where the great-grandfather, grandfather, father and son are imprisoned."

Colombia's narco-business has given rise to many tragedies. This is just one more.

The Caribbean island that scorned tourism

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Hernando Alvarez talks to people on Old Providence and admires their laid-back, unhurried approach to life.

This is part of the Island Stories series.

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