Thale Noi is for the birds, always has been and always should be. This "Little Lake", obscurely tucked away in a corner of southern Thailand's all but forgotten Phattalung Province, appears as little more than a dot on a topographical map. But the birds know where it is. They flock here in staggering numbers from as far away as the Siberian Arctic to join resident species each winter. More than 43,000 waterfowl descend on this amazing wetland during the peak tourist months of November through February. Like many foreign tourists, the birds are drawn here by the area's agreeable winter weather, fabulous food, friendly people and, for some species, the best opportunities to mate.

What makes Thale Noi one of the Kingdom's greatest natural treasures is not the number of birds, however, but the astonishing diversity of species. No fewer than 187 species – ducks, geese, storks, rails, cormorants, stilts, jacanas, kingfishers, herons, egrets, terns, swallows, raptors and many others are known to depend on the Thale Noi wetlands. As any ornithologist can tell you, that's a huge species diversity for so small an area. It represents nearly half of all bird species found in Canada the world's second largest country in land area. Though few know that Thale Noi exists, and fewer still have ever visited the site, it's the first site in Thailand to be internationally recognized as a Ramsar Site – a wetland of global significance.

It's not often that one comes across a showcase for conservation in Thailand or, for that matter, in any other part of the world. So many of the world's "protected areas" are plagued with problems: illegal logging of forest reserves, encroachment by settlers, flooding from ill-conceived dams, poaching of park wildlife and growing impacts from tourism. Anger and a sense of alienation on the part of local residents who don't feel they were part of the decision-making process is often the most serious deterrent to conservation efforts.

All too often tourism authorities, conservation agencies and environmental groups try to persuade locals to support a conservation project based on the expected generation of income from tourist dollars. If this windfall fails to materialize, poor people usually revert to the resource-extraction activities they conducted before the protective status applied. Establishment of the Thale Noi Non-Hunting Area was a delightfully refreshing change from these typical and predictable scenarios, for it was the villagers themselves who first called for the area's protection.

In 1974, a group of subsistence fishermen living in the little village of Ban Thale Noi collectively proposed to the Wildlife Management Section of the Royal Forestry Department that Thale Noi be protected as a "waterfowl park". They had witnessed a steady decline in bird numbers, as larger species were being hunted for food. There was fear that species such as the magnificent painted stork might disappear altogether.

So why were uneducated fishermen more concerned with the welfare of Thale Noi's waterfowl than were the university-educated government ministries entrusted with protecting this resource? The answer is simple: the fishermen could see the importance of birds to their fishery through everyday experience. Over the years they'd developed a mutual, if not symbiotic, relationship with their wet-feathered friends.

Waterfowl droppings, rich in phosphates and nitrates, are responsible for nourishing Thale Noi's great abundance and diversity of aquatic plants: bulrushes, water lilies, lotus, water hyacinth, typha reed, water fern, water gentian and others. These plants in turn provide shelter for the fish and food for the insects the fish feed upon, plus they oxygenate the water to prevent the lake from becoming stagnant and unsuitable for large numbers of fish.

Whether they realized it or not, Thale Noi's birds had become as dependent on the fishermen as the fishermen had become on them. Poles cut from swamp forest trees have always been driven into the shallow lake bottom so the fishermen can secure their gill nets. These provide the lake's only perches for many species of kingfishers, terns, bee eaters, trogons and cormorants; they use the poles to rest between feedings, to preen and dry their feathers, and to roost overnight. The poles also serve the important purpose of providing anchors to trap and hold floating vegetation like water hyacinth. Rafts of such floating plants provide the nesting platforms of purple swamp hens, grebes and jacanas. The rafts also provide the fodder for the giant snails which both the birds and the fishermen utilize for food.

The daily movements of the fishermen across the lake help keep the channels open through the dense growth of aquatic plants. This benefits cormorants and kingfishers, who depend on open water to spot and dive for fish. When revving the longtail props on their boat engines, the fishermen further oxygenate the lake, to the benefit of the fish.

Reeds harvested from the shallow waters of Thale Noi have been utilized for centuries by village women. Pressed, dried and dyed, they're woven into some of southern Thailand's finest floor mats, hats, purses and other crafts. Harvesting bulrushes and reeds in this sustainable fashion stimulates new growth, much like pruning a hedge, and many species of waterfowl like the cotton pygmy goose, the lesser whistling duck, and garganey benefit from healthy bulrush beds where they both feed and find shelter.

There are many places around the world where bird populations and commercial fisheries are inextricably linked. The classic case is that of the Peruvian anchovy fishery. In the time of the Incas, seabird populations along the arid Peruvian coast were among the highest in the world. Offshore islands where seabirds nested were deep in droppings, or guano, and this became the main source of nitrogen-rich fertilizer with which the Inca nourished their soils. So successful was potato cultivation in the Inca Empire that they were one of the only civilizations in human history never to know famine.

The phenomenal seabird concentrations here were due to converging warm and cold oceanic currents, where huge numbers of anchovies fed in the rich offshore upwellings. When modern Peruvians over-fished their waters, not only did the anchovy fishery collapse, so did the seabird populations which depended on these small fish as their dietary mainstay. The fishery has never fully recovered from this biological catastrophe. Years later scientists found that it had been the phosphates and nitrates in the seabird droppings that nourished the phytoplankton in the littoral waters. The phytoplankton provided the food for the zooplankton which fed the small krill and fish the anchovies fed upon. The loss of the anchovies resulted in the immediate loss of the seabirds and their droppings which had, for millennia, fuelled this whole dynamic cycle.

Thale Noi may represent one of Thailand's best examples of this type of nutrient economy. The beautiful balance between the birds and the fishermen of Thale Noi could continue indefinitely, with no need for the area to generate tourism revenues. But rapid change is the order of the day in Thailand, and no protected area seems safe for long. Today Thale Noi is having its drainage pattern radically altered by a roadway being constructed along its southern boundary. Once again, as the lake rises to dangerous levels, the fishermen are trying to save their fishery and their beloved birds from catastrophe. The roadway is now holding back the waters that drain the vast peat swamp forests of northern Phattalung Province from its normal drainage out to sea through the great inland lagoons to the south. Thale Noi, the Little Lake, with an average depth of only 1.5m, is now double that depth. Shallow-water feeders such as ducks and geese have difficulty reaching the lake bottom to feed, when the water is so deep, and local fishermen are concerned at the dramatic reduction in bird numbers. The few local proponents of the roadway say it'll shorten the driving time to Songkhla for shopping, an advantage of questionable value. A little added convenience is a huge price to pay for the loss of one of the world's richest wetlands.

Thale Noi has yet to attract foreign tourists in any significant numbers. Apart from the few dedicated ornithologists and amateur birders who find their way here, it's largely visited only by Thais. The Tourism Authority of Thailand (TAT) has been trying to promote the site, and eventually it might become one of the South's hottest eco-tourism destinations.

Even those who aren't keen on birds can't help but marvel at the beauty of a Thale Noi dawn. As the sun rises over the Gulf of Thailand and casts its first warm rays across the mirror-like surface of the Little Lake, the largest display of water lilies in Thailand open their blazing pink blossoms in greeting. It's pure magic - an Alice in Wonderland wetland. Purple swamp hens with their bright blue plumages and huge feet walk across the lily pads in search of giant snails. Great flocks of snowy white egrets, jet-black cormorants and boldly patterned ducks, geese, terns and swallows fill the sky with life and movement in every direction. Huge purple herons, startled into flight from the concealment of tall bulrushes, offer heart-stopping moments as they rise on massive wings like prehistoric birds of prey. Brilliant neon-blue kingfishers light up the eyes of early morning birders with their bold plunges, while sea eagles and brahminy kites ride the first updrafts of the rapidly warming day.

One doesn't have to be an avid birder to find oneself bedazzled by Thale Noi's beauty and vital exuberance, and one doesn't have to be a conservationist to be concerned for the Little Lake's future. Striking the right balance between the needs of waterfowl, fishermen, local residents and visitors can be accomplished, but it requires immediate attention. Thale Noi is too precious a jewel in the Kingdom's crown to be forgotten.