Ever-changing constellations of islands recede into the distance ahead as we sail up the Burmese coast from Kawthaung, the southern-most town in Myanmar. Deserted white-sand beaches backed by prime rain forest line the shores, and mountain peaks on the larger islands beckon from many miles away. We’ve cruised most of the day without spotting another vessel.

Then we encounter a scene out of some Hollywood fantasy. Snugged in between a couple of uninhabited isles lie a congregation of exotic wooden boats, each raggedly festooned with lines and pennants and teeming with men, women, children and dogs. And there’s more to come. Some miles off the nearest island, the next day, we spot a train of 14 dugout canoes full of women and girls in tow behind one of the same odd-looking wooden houseboats. A week later, off yet another island, we make way for a fleet of dugouts streaming back to a be-pennanted mother boat with the afternoon’s catch, where bare-breasted women have been diving from their canoes for a variety of marine organisms, including shellfish, crabs, shrimp and sea cucumbers. On the tidal flats in front of a temporary encampment, young boys are spearing stingrays with tridents longer than themselves. A few women and children dig sand worms along the waterline.

There’s a dreamlike quality to cruising this archipelago. These scenes have the flavour of other times and other worlds. And 100 years ago the sense of mystery and wonder was much the same:

Some assume that they were originally an offshoot of the Veddas, the aboriginal inhabitants of India. There are those among the Moken themselves who suggest they made their way from the Nicobar Islands, whether directly or else by island-hopping up through the Andaman Islands and then along the southwest coast of Myanmar. (Turn-of-the-century encyclopaedias did describe the "Selungs" as inhabiting both the Mergui Archipelago and the Nicobars.) Most experts, however, believe they migrated up the coast from the Riaw-Ringga Archipelago, south of Singapore.

The Moken are related in uncertain ways to other groups of sea nomads inhabiting the waters of the Malay Peninsula. The Mergui Archipelago population, however, is that least affected by mainstream societies. Most speak only Malay and Moken, an Austronesian language, together with a few words of Burmese or Thai. And these "Burmese" Moken are the only group of sea nomads, among an estimated total of 20,000, who remain largely uninfluenced by Islam or Buddhism.

The groups farther south have settled in coastal villages, for the most part. The Moken, on the other hand, have long been nomadic hunter-gatherers whose range is mainly limited to the littoral zones — the shorelines, together with their contiguous marine and forest shallows — of some of the more than 800 islands of the Mergui Archipelago, which extend hundreds of miles up Myanmar’s southern coast. A lesser number inhabit the Surin Islands and Phuket, in Thailand. Moken communities are organized on kinship groups — exogamous extended families — based around flotillas of six-eight boats, each fleet having its own loose territory. Although estimates vary — given the difficulty of counting such a shy people dispersed over such a broad and largely wild area — 2,000-3,000 Moken with somewhere between 200 and 500 houseboats still maintain a semi-nomadic lifestyle in the Mergui Archipelago, a few still travelling back and forth across the border in their boats to visit kindred communities in Thailand.

These people recognize two main seasons — the wet May-October southwest monsoon, and the dry October-May northeast monsoon. Traditionally, families spend six-eight months aboard their distinctive wooden boats. They stay ashore only in the wet and blustery southwest monsoon. In the latter season, you might sail around a point of land and into a protected cove where you find yourself confronted with a scene from another age. And the Moken are as startled to encounter you as you are them. The boats have motors instead of sails, and plastic oil bottles serve as marker buoys; otherwise, the scene could as easily be from 100, even 200 years ago. An animist totem pole stands in the centre of the stilted and thatched village of 20-30 dwellings, and work is proceeding on the dugout keel of a traditional houseboat. In the wet season, they occupy their time with boat maintenance and construction, hunting wild pigs and other small game, gathering fruit and vegetables and digging for wild yams.

Historically, the Moken have sought home ranges both rich in littoral resources and remote from other cultures. Eighty-odd years ago, one British observer reported that the islands were very seldom visited, and those who did go there tended to be Christian missionaries or government officials: "The former want taxes and the latter want to convert them; and the [Moken] is very timid, and avoids both."

But today the winds of change are blowing in earnest. Sights such as the rainy season village described above are only rarely encountered. In the interests of bureaucratic efficiency and political security, the nomads are being encouraged to give up their nomadic ways and settle in easily administered areas. The Burmese government has established a permanent settlement on Pu Nala, just south of Lampi Island. As you round the north end of the island, you sight a small pagoda on a grassy hill. Back of the beach stands a coconut grove and several dozen atap huts on stilts. High-prowed wooden longtail fishing boats lie at rest along the waterline. Farther up, on the sand, several of the distinctive traditional live-aboard Moken vessels, weathered and to all appearances derelict, sit high and dry. (Burman fishing boats are also in evidence, for a number of Burmese have settled here as well.) The Myanmar government has built the pagoda, a monastery, school and even a small museum to cater for tourists. Every two months, it also supplies the village with essentials which, together with the educational facilities, provide incentive for Moken families to relocate. Shops offer everything from biscuits to cigarettes and beer; though you still find sea cucumbers, delicacies for trade in Ranong or with visiting dealers from Mergui Town, drying over charcoal fires in the main street.

The trade-off, of course, is exposure to Burman and other cultures, Buddhist assaults on their traditionally animistic beliefs, and loss of at least part of that indigenous knowledge that allowed them, on the one hand, to brave the elements for eight months of the year aboard their famously seaworthy boats, and, on the other, enabled them to survive in a sustainable relationship with the littoral ecosystem.

The fringing reefs of the Mergui Archipelago are still rich in marine life. The forest remains home to all sorts of wildlife. Early in the past century, the Mergui Gazetteer, for example, listed the following animals for the district: gibbons, flying lemur, jungle-dog, flying fox, civet, tiger, leopard, bear, elephant, boar, mouse-deer, sambhar, barking deer, bison, wild cow, tapir, rhinoceros (single- and double-horned), turtle, python and cobra. Virtually all of these species still inhabit these islands, although some are now threatened with extinction.

What is perhaps an even more profound tragedy, however, goes relatively unremarked. The indigenous sea nomad culture — as rare and as endangered a phenomenon as any animal species in the region — may truly be dying at last.