By Alfredo Quarto

Mangrove forests are made up of diverse tree species which thrive in upper tidal zones along flat,sheltered tropical shores. The trees have evolved in the harsh environment of brackish water and changing tides. Their special adaptive aerial roots and salt filtering tap roots have established rich and complex ecosystems. Besides protecting vast areas of coastline from erosion, they are vital to inshore fisheries, wood-products industries and wildlife.

In the mangrove forest, life abounds. One can find shorebirds, crab-eating monkeys, fishing cats and mudskipper fish that skim across the swamp mud to make their way between water holes at low tide. The mangroves are the ocean's equivalent of the rainforest, balancing coastal ecosystems worldwide. Living along these once vast areas of coastal forest, villagers pass along their traditional cultures to their children - skills and wisdom relating to the sea, the land, and of course, the mangrove forests.

But time is running out for the mangroves and the people who live among them. Because of their proximity to the sea's brackish waters and their relatively level terrain, the mangroves are ideal locations for establishment of black tiger prawn agriculture. They are being cleared, and the once self-sustaining waters and lands poisoned. "I know I have this sin on my conscience I may never be able to erase..." a small prawn farmer on the East coast of Thailand admitted. He acted against better judgement and took a chance to make quick profits at the cost of his neighbour's rented land. The 20-rai prawn farm failed, the land is ruined.

The story was the same among villagers on the Andaman Sea coasts. The fever which had struck the east coast was upon them, yet they were fearful to act. Others who had spoken out had felt the heavy hand of "influential people". Billions of baht are at stake. The land-grabbing is backed by certain policy makers who share the money gained from illicit land deals and a passing fancy: the boom and bust of black tiger prawn agriculture.

Prawn farms made their first appearance along Asia's farm coasts the 1970s, beginning their rapid expansion in China, Taiwan and South Korea. The annual growth rate of prawn production averages 25%, mainly in Asia which produces 75% of the world's prawns. Many of these early prawn industries have by now failed or are in their final stages. The ponds are largely abandoned, the once plentiful mangroves are devastated.

Business investors from these early enterprises, undaunted by the inevitable failure of their prawn farms, looked further afield, to Thailand, India, Bangladesh, the Philippines, Indonesia and Malaysia. Prawn industries were established in Ecuador, Panama, Mexico and elsewhere in Latin America. Wherever the industry goes, the mangroves disappear as it moves on from failed ponds to new, unspoilt ground.

The main defect in the prawn aquaculture lies within the pond's waters. Fresh seawater must be pumped regularly into the ponds to keep the prawns healthy. The pond's fouled waters, which contain toxic concentrations of prawn excrement and the chemical additives used in the prawn feed and water treatments, must be pumped out. The problem is, where to place pond effluents without contaminating surrounding land, ground waters, and the coast itself?

No adequate solution has been found, and problems with pond effluents have been mounting. In addition, salinization is poisoning the ground water, as well as the once productive farmlands. Waste water is adversely affecting the coastal ecology, killing off the sea life and destroying vital fisheries. In time the ponds poison themselves as the seawater used to recharge them becomes contaminated, weakening prawn production, until finally the ponds are closed.

Besides the very obvious degradation of coastal ecosystems, aquacultural production has other grave consequences. Overuse of fresh water for the ponds can cause shortages of drinking water, ruin nearby croplands, land subsidence and salinization of groundwater supplies. Mangrove forests offer a wealth of wood products, including charcoal, paper, building materials, firewood and rayon.

However, the industry converts this once-public, multiple function resource into a private, single-purpose production unit.

Even now, the prawn industry is moving towards new coasts in Burma, Cambodia, Vietnam, Yemen and Iran. Business continues to make big profits from selling prawn feed, water treatment additives and equipment to small farm owners.