The tsunami-environment connection

World Reports

Reef Protection International

Eleven countries were hit by the December 26 tsunami. Scores of other countries lost citizens, making this a worldwide catastrophe. Legions of aid workers are now helping people in the worst-hit areas of Indonesia, Sri Lanka, India, and Thailand. Now that the horrible images from the tsunami are no longer a constant presence on cable news, the development community has begun to ask what must be done to restore the damaged areas, displaced lives and livelihoods and, most of all, people’s hope. Along with ensuring that aid gets to the victims of this disaster, it is equally important to make sure that the fragile ecosystems in these areas have the chance to recover fully. This will require that rebuilding efforts don’t add to the damage that has already occurred there.

Even before the earthquake and tsunami, this region’s rich biodiversity was already under attack. Mangrove forests were being converted to highly polluting shrimp farms. Overfishing and collection for the aquarium trade had left some coral reefs barren. Precious forests on Sumatra had been reduced to a sliver to meet the demand for exotic-wood furniture. Much of this activity was funded through grants and loans from the development community in an effort to hasten social progress and alleviate poverty. Sadly, these efforts failed miserably in achieving their ambitious goals. As a result, people were left under increasing duress as the natural resources they relied on for their sustenance and protection were damaged.

Along with ensuring that aid gets to tsunami victims,
we must make sure that the fragile ecosystems in
affected areas have the chance to recover fully.

Mangrove forests once covered 75 percent of the coastlines of tropical and sub-tropical countries. Today, less than 50 percent remain, and of the remaining mangrove swamps, over half are degraded and in very poor health. Mangrove swamps cover an area of around 15 million hectares (or 150,000 sq. km.) worldwide, almost 40 percent of that in countries affected by the tsunami. Commercial shrimp farming took off as a venture during the 1970s in Central and South America, and really took hold in Southeast Asia in the mid-’80s. Mile upon mile of mangrove forest was converted to shrimp ponds.

The true value of mangrove swamps wasn’t fully recognized until it became evident that they were disappearing at an incredible and dangerous rate. “ Mangroves contribute directly to rural livelihoods by providing wood and non-wood forest products… and indirectly by providing spawning grounds and nutrients for fish and shellfish. Mangroves can also help protect coastal areas from future tidal waves,” says mangrove expert Mette Løyche Wilkie of the UN Food and Agriculture Organization.

In 1985, world production of farm-raised shrimp hovered around 200,000 metric tons, about 10 percent of total world shrimp supply. About three quarters of that was produced in Southeast Asia. In 1987, the US National Marine Fisheries Service released a new estimate of world shrimp farm production for 1986. This estimate came in at a whopping 300,000 metric tons.

It was about this time that problems began to appear. Industrial and domestic pollution, combined with the effluent from intensive shrimp farming, severely polluted the local waters. The water was so contaminated that farmers ended up pumping each other’s effluent. Farmers, overwhelmed by the amount of sludge that built up on the bottoms of their ponds, were forced to pile it on the pond banks, creating an ideal home for pathogens and toxins.

As the industry exploded, the price of shrimp crashed. This forced many farmers, already saddled with debt, to leave their ponds fallow. In the early 1990s, shrimp farmers in Thailand went out of business by the hundreds, if not thousands.

This boom-and-bust story is almost always the same. The effluent from intensive shrimp farms overwhelms the local waters, then backs up into the farms as the dirty water is all that is left to pump into the ponds. This stresses the shrimp, making them susceptible to pathogens that eventually cause massive die-offs. This rampant pollution not only affects the shrimp farms, but the same polluted water is then spread throughout the coastal region slowly killing remaining mangrove forests and, eventually the shallow coral reefs that dot the coastline. Reef-building corals, such as those found in the Indian Ocean, require clean, sunlit water to thrive. Not only does the effluent from shrimp farming severely degrade the water, but its cloudiness gradually kills the coral reefs.

Mangrove forests act as a nursery for juvenile marine life. Post-larval animals congregate amongst the roots of the mangrove swamp for protection from predators. Eventually, they reach adequate size, and with the aid of tides, settle onto coral reefs in a process called “recruitment.” Mangrove forests also provide safe haven for more pelagic (ocean-going) species like jacks, a primary food fish and income source for locals. Mangroves support fishermen by helping to keep fisheries going, and hospitality businesses by maintaining healthy coral reefs to attract scuba divers. The short-term profit from industrialized shrimp farming practically nullified these ecological and economic benefits in much of this region.

In the aftermath of the devastating tsunami, as early reports of damage began filtering in, it became evident that areas with intact coastal ecosystems suffered much less damage than those where development had damaged mangroves and coral reefs. Formal research is necessary before solid conclusions are drawn, but anecdotal accounts confirm the dramatic effect natural buffers such as intact mangrove swamps and healthy coral reefs have had in minimizing the damage. During the recent tsunami, the Pichavaram mangrove swamp in Tamil Nadu in India slowed down the waves, protecting around 1,700 people living in settlements built between 100 to 1,000 meters inland from the mangroves. In Malaysia, the Penang Inshore Fishermen Welfare Association observed reduced damage in areas where the mangrove forests had been left intact. Sri Lankan officials made similar observations. The death toll in the Indonesian island of Simeuleu, located close to the epicenter, was relatively low. This was partly due to mangrove forests that surrounded the island.

Thus shrimp farming caused a cascade of devastating effects on the coastal environment – mangrove forests are lost to create shrimp ponds, effluent from the shrimp ponds pollutes coastal waters, polluted water is pumped back into the shrimp ponds causing die-off, and then goes back out to sea killing the remaining mangrove forests and shallow coral reefs along the coastline. Not only are people in these countries left without the work on which they had built their livelihoods, they have lost the very natural resources that sustained and protected them for generations, all in the myopic quest for short-term profit. Now as these same well-meaning institutions rush in to help rebuild the tsunami-affected region, a conscious effort must be made to ensure this cycle is not repeated. Commitment must be made to ensure that coastal construction is done in balance with the critical ecosystems of the area. Equally important is the need to implement programs that will restore mangrove forests, in addition to coral reef restoration, so that the coastal environment in this region can heal and, by doing so, provide livelihoods and hope to the people who have suffered this unimaginable loss.

Drew Weiner is the director of Reef Protection International (RPI), an Earth Island project. RPI educates the public about the marine aquarium trade and promotes consumer behavior that enhances coral reef conservation. To learn more about RPI, visit its Web site at:

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