ACHUTUPO, Panama -- After keeping the world at bay for five centuries, the Kuna Indians on Panama's unspoiled Caribbean coast now confront an insidious intruder: cocaine traffickers.
The fiercely independent tribe inhabits Kuna Yala, an semiautonomous region that includes a coastal strip and the San Blas islands. The region is known mainly to foreign ecotourists who can afford to reach its isolated white sand beaches.
The Kuna have fought off incursions by Spanish conquistadors, rubber growers, gold miners, and, most recently, tourism promoters. But they jealously protect their sovereignty, won after a bloody uprising in 1925. Today, the tribe permits no outside ownership of its land.
The Kuna control nearly 400 picture-postcard islands but inhabit fewer than 50 of them, which are crammed with bamboo-sided, thatch-roofed huts. The women are known for their gaily-colored dresses and embroidered molas, or tapestries, a coveted souvenir. Men spend the day fishing, gathering coconuts, and catching lobsters.
In the past few years, however, the Kuna have faced an interloper that has proved difficult to fend off -- and has brought the scourge of addiction.
The 200-mile-long Kuna lands lie just south of a transit route for Colombian drugs on their way to the US market, much of them stowed aboard sleek, 40-foot fiberglass boats often outfitted with a trio of 200-horsepower engines and guided by satellite-positioning systems. The boats can carry up to 2 tons of cocaine, typically in 40-pound watertight packages.
A consequence of the increasing drug traffic is that ever larger amounts of drugs wash ashore in the region, having been dumped by runners to avoid detection or to be picked up by associates. The cocaine gets sold or used locally.
The boats make surreptitious refueling stops on the high seas or along the Caribbean coast and have proved elusive to US and Panamanian authorities trying to stem the flow of drugs. They are difficult to track and intercept because their speeds reach 80 miles per hour and they travel at night.
Officials who run the US-Panamanian drug interdiction program say they have had success recently in catching some of the boats.
This nation's top antidrug prosecutor, Patricio Candanedo, said that in 2005, Panama seized 35 tons of cocaine in seaborne raids, nearly four times as much as in 2004.
One American official said the antidrug efforts have been helped by a US gift of several fast boats that Panamanian law enforcers now use to chase down the drug runners. But the surveillance has pushed drug boats' skippers to run closer to Kuna Yala shores, so they can ditch their boats and cargo more quickly.
And that has increased the incidence of what the locals call ''ocean jackpots," or the recovery by Kuna tribesmen of cocaine that is then distributed locally. On some islands, up to half of Kuna men between 18 and 25 are now addicts, said pharmacist assistant Galindo Morales, who works at this island's health clinic.
''The addiction problem is on the rise," said Dr. Edison Murillo, who directs a hospital on the neighboring island of Aligandi.
Kuna Yala's idyllic surroundings mask several health problems among the 60,000 members of the tribe, he said, including AIDS, malnutrition, and tuberculosis, in addition to drug abuse.
Anthropologist Stanley Heckadon of the Smithsonian Tropical Research Institute in Panama City hypothesized that a possible reason for the rising drug use and trafficking among the Kuna was the 1999 transfer of the Panama Canal from the United States to Panama, as well as the closing of several US military bases, which left up to 3,000 tribe members without jobs.
''The Kuna had a long history working for the canal administration and the US military as painters, busboys, and cooks," Heckadon said. ''Suddenly the bases were shut, and men who had a good income before now don't have a job but still a family to support."