Rainforests of the sea: mangrove forests threatened by prawn aquaculture.

In the mangrove forest, life abounds. Here live shorebirds, crab-eating monkeys and mudskipper fish that skim across exposed swamp mud to make their ways between water holes at low tide. The mangroves have been called the "rainforest of the sea." These trees have evolved in harsh environments of brackish waters and changing tides, establishing balanced, complex ecosystems along the tropical coasts of Africa, Australia, Asia and the Americas.

Mangrove forests are vital to healthy coastal fisheries, sustainable wood production and wildlife habitat. The fallen leaves and branches of the mangroves provide rich nutrients for a variety of sea creatures who feed on this decaying matter. And the shallow intertidal mangrove swamplands offer refuge and nursery grounds for developing fish fry. In fact, much of the tropical world's sea life gets its start within the tidal waters of the mangrove swamps. And living among these mangrove forests, native people pass traditional culture and survival skills on to their children and grandchildren - age-old wisdom relating to the sea and the land.

The mangroves' specially-adapted aerial roots and salt-filtering tap roots enable these trees to occupy the fluctuating intertidal zones where other plants cannot survive. These resilient forests are literally living in two worlds at once. They are the connective tissue between sea and land, playing an invaluable role in protecting coastal areas from erosion, storm damage and flooding. Thousands f miles of tropical and sub-tropical coastline are stabilized by their interwoven roots.

Yet today, the world's mangrove forests are endangered. Pollution and development from expanding industries have resulted in mass mangrove destruction. One practice that stands out as a major contributor to mangrove loss is the raising of prawns (shrimp), mainly for export - through a practice known as aquaculture.

This profitable industry grew up along the rich mangrove coasts of Asia in the early 1970s and blossomed in the 1980s. In just a few years, entire mangrove forests were cleared and the bulldozed, then pitted with large shallow containment ponds which held their growing wealth - masses of black tiger prawns. Processed feed and medicines were added to these artificially-controlled pond environments to increase production for the international market (mainly Japan and the United States, followed by Europe, Singapore, Hong Kong and Canada). Because early ventures were so successful, commercial operations expanded into a multi-billion dollar industry.

However, the loss of the mangroves set in motion the destabilization of entire coastal zones. The resulting erosion and heavy siltation destroyed sea grasses and corals, further diminishing the coastal habitat for birds, sea turtles, dolphins, manatees, otters and a host of fish, mollusks and crustaceans.

This habitat loss in turn brought the sharp decline of the local fisheries, mounting soil and water pollution, and the displacement of thousands of traditional coastal people, mainly farmers and fishers. In Bangladesh alone, over 100,000 coastal residents were forced off their land. Such landless poor, having lost the traditional means of sustaining themselves, often move to cities where they join the ranks of other unskilled urban dwellers struggling to survive in over-crowded, squalid conditions.

In just a few years prawn operations began closing down because of mounting pollution problems within the ponds that eventually weakened or killed the prawns themselves. As the waste water was pumped out, it poisoned the surrounding soils and leached salt into the underground aquifers, contaminating drinking water. And when the old ponds closed down due to loss of productivity, new ones opened elsewhere on newly cleared mangrove land.

Originally, many coastal farmers and fishers got caught up in the "prawn fever" which swept like wildlife through Asia's extensive coastal regions and parts of Latin America and Africa. As early prawn farmers ran out of usable coastline for their short-term profit-making enterprises, they broke ground in other places. Because early profits were so great, it took little time for both local and foreign investors to expand this damaging industry. With the promise of lucrative export income, governments, of developing nations also succumbed to prawn fever and loosened their mangrove protection measures, clearing the way for massive cutting of mangrove forests.

In 1983, the total area of mangrove forests worldwide was approximately 15 million hectares. Today only half of that area still stands. Taiwan has lost almost its entire mangrove forest area and Thailand and Ecuador are running close behind.

Both local and international pressure to stop the cutting is growing, and recently resulted in the establishment of the Mangrove Action Project (MAP), an international coalition of environmental, human rights and consumer protection groups. MAP hopes to protect the world's remaining mangrove forests and ensure the rights of indigenous coastal people by encouraging governments to control the prawn industry worldwide, raising public awareness about the issue, and dissauding consumers from buying prawn products.

Says Mad-Ha Ranwasii, a Thai MAP member, "if we allow the roots of the sea to be severed, the whole tree may come tumbling down." Contact: Mangrove Action Project, P.O. Box 1854, Port Angeles, WA 98362-0279; The World Bank, 1818 H Street NW, Washington, DC 20433/[phone]; The India Consulate, 2107 Massachusetts Avenue NW, Washington, DC 20008/[phone].