The Environmental Hazards of Intensive Shrimp Farming on the Mekong Delta - Pacific Standard

The Environmental Hazards of Intensive Shrimp Farming on the Mekong Delta

Vietnam either has to change the way it approaches shrimp farming or face the loss of hundreds of hectares of land.
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A shrimp farmer uses a plastic basket to move shrimp from one holding pen to another in a pond in the My Xuyen district in southern Vietnam.

A shrimp farmer uses a plastic basket to move shrimp from one holding pen to another in a pond in the My Xuyen district in southern Vietnam.

Shrimp farmer Nguyen Manh Hung lost his entire farm to erosion in 2016 after a series of ravaging droughts and floods. He and his family had relied on their land for over 27 years, and, with three children to feed, the loss came as a tremendous blow.

"[First], the land turned bad. We had a drought. You could look into the soil and you would see clumps of white," Hung told Mongabay. "Nothing would live off of that land and not much in the water either."

Like many small-scale shrimp producers in this part of Vietnam, Hung had been using an intensive method of farming focused on producing high yields. In these models, farmers clear as much of their property as possible to make way for earthen shrimp ponds, often lined with tarpaulin.

"Back then we farmed shrimps in ponds, dug by hand and then machines when we got money," Hung remembered. "You had to ... fell trees to make the ponds: one big main pond, one pond for processing, and three smaller ponds on the side."

But with no trees to hold nutrients in the soil or keep the salty water table down, Hung's farm was completely exposed to the elements. As well as drought, a series of devastating floods in 2002, 2008, and 2016 ripped more sediment from the banks of his ponds, and his land eventually became so badly degraded that he could no longer use it. After years of borrowing money, failed harvests, and the loss of his entire farm, the family was over $1 million in debt to the bank, he said.

Hung's situation is all too common in Vietnam. Yet shrimp farming remains popular, because while the risks are very high, the potential earnings are higher still. This is also true on a national level. The shrimp business is one of the biggest industries in Vietnam, and the government is pushing to expand it, having announced plans last year to boost exports from $3 billion in 2016 to $10 billion by 2025.

But there are significant environmental problems associated with current farming methods. Deforestation, erosion, rapid land subsidence, and rising salinity levels are threatening the stability of the entire Mekong region, and while shrimp farming does not take the blame alone for these issues, it is a substantial part of the problem.

As a result, the Vietnamese government and a range of international development partners are working together to improve the way the country farms shrimp, with an emphasis on small-scale operators like Hung. They are setting new targets for sustainable aquaculture along with incentives for farmers to reach them, but the reality is that most intensive shrimp farmers are reluctant to change.

Farmers Under Pressure as the Mekong Delta Suffers

Although intensive shrimp farms occupy less than 10 percent of the 1.5 million acres devoted to shrimp production, they produce approximately 80 percent of Vietnam's total shrimp output. So-called improved extensive shrimp farms, also run by households but with lower overheads and smaller yields, occupy far more space: about half the country's shrimp production land (833,000 acres). Both methods require mass-scale mangrove clearance, total land renovation, and a great deal of artificial feeding and chemicals, so efforts to improve shrimp farming target both.

First and foremost, these farms are a leading cause of deforestation. In the typical small-scale shrimp farm, every square inch of land is cleared of mangroves and other vegetation for production, cumulatively leaving vast stretches of coastline open to erosion. This is a huge problem in a region of the world that is already very close to sea level, threatening both the future of shrimp farming in the area and the broader ecosystem, according to Andrew Wyatt, the Mekong Delta program manager at the United Kingdom-based non-governmental organization International Union for Conservation of Nature.

"Many of [Vietnam's] coastlines are very vulnerable because there are no trees on them," Wyatt told Mongabay. "[Coastal] mangroves will eventually disappear ... and then all that shrimp farming land behind them is completely exposed to storm surges and winds, typhoons, etc."

Another big problem with these shrimp-farming methods is their role in land subsidence. To maintain water quality and salinity levels in their ponds, farmers are pumping enough groundwater to contribute to the decreasing elevation of the Mekong, according to Wyatt. As a result, seawater is intruding further into the delta, threatening Vietnam's food supply and economy. The Mekong Delta is responsible for half of the country's staple food crops and 70 percent of its rice exports, and is one of the most productive and densely populated areas of Vietnam. But as salt levels rise, rice crops are failing and even shrimp yields are declining.

"Shrimp has a maximum tolerance for salinity," Wyatt said. "During extreme weather conditions ... the salinity levels in the rivers where the major intensive shrimp growing areas are can exceed these tolerances."

Duong Le farms whiteleg shrimp intensively in Long An province, in the upper Mekong Delta. He told Mongabay that, although he has not lost any land to erosion, salinity levels on his farm have increased in the last few years. To counteract the rising salinity levels, he now has to pump even more groundwater into his ponds than he once did.

Last September, at a two-day conference of top Vietnam officials, Tran Thuc, vice chairman of the government's advisory panel on climate change, named subsidence as the most immediate threat to the Mekong Delta. Officials said the Mekong sank two to four inches between 2010 and 2015, and continues to subside steadily. Add erosion—which has taken around 741 acres of land every year since 2005—and the government warned that the Mekong Delta may disappear entirely within the next 100 years if drastic measures are not taken now.

Another issue with shrimp farms is pollution. Most shrimp farmers in Vietnam rely on a range of chemicals, medications, and supplements to keep their shrimp healthy, much of which is released into public waterways along with old pond water.

"When I start a new yield, first I clean the water, then put the new baby shrimp in there and feed them with nutrients and medicine every few days," Le said "When they are older I have to treat them more often—every day, even day and night if necessary."

Le adds chemical solvents to his ponds two times per yield to clean the water and keep the shrimp free of disease. "It depends on the weather as to what the shrimp might be sick with," he said. "They could get white spot or sometimes a liver infection where the heads don't grow but the body does. It stops their growth and the head gets smaller and they die."

Le has never set aside land for treatment ponds to reduce the used water's chemical and nutrient loads before releasing it back into public waterways. It just isn't profitable. "When I harvest the shrimp I let all the old water out into the river and take new water in. Then I treat it and start again," he said.

A number of studies link intensive shrimp farming to organic pollution in nearby waterways. VietnamNet news has reported that, because most intensive farmers discharge pond wastewater without treating it, the water that other farmers then pump into their own farms is not clean. This has led to a rise in chemical use to rid the water of organic matter, further polluting it, and continuing the cycle.

Many farmers are simply not aware of the damage their farms may be doing. When asked if he considers his impact on the environment, Le responded that the factories upstream from his farm are the ones doing the damage, not him.

Smallholders Turn Slowly to Integrated Farming

Faced with a rapidly deteriorating Mekong region and the challenge of working with thousands of small farmers like Hung and Le, Vietnamese authorities and outside partners, including the IUCN and World Bank, are still grappling with how to move the shrimp industry forward.

Last October, Prime Minister Nguyễn Xuân Phúc signed a key commitment called Resolution 120 aimed at sustainable development of the Mekong Delta that sets clear environmental goals for the region's aquaculture sector, according to Wyatt. And a number of projects are already being implemented to put this into practice.

One such project is Mangroves and Markets (MAM), started in 2013 by the IUCN and overseen primarily by Wyatt. The program transitions small-scale intensive and improved extensive shrimp farmers to a more environmentally focused method of production known as integrated shrimp farming in which shrimp and mangrove forests co-exist.

MAM provides incentives for farmers to increase tree coverage on their farms and maintain existing cover. Under MAM, farmers keep shrimp in mangrove-forested waterways, cut off from the main Mekong river system. The shrimp grow as they would in the natural environment, without chemical inputs and often with other naturally occurring harvestable species, such as clams, cockles, and oysters. Farmers receive training to maintain their farms and meet the program's standards, and their shrimp is eventually certified as organic through Naturland, a German standard for organic produce used widely across the European Union. Over 2,000 farmers had achieved Naturland certification by the end of MAM's first phase, in 2016. The project aims to train and certify a further 3,000 by the end of 2019.

These integrated mangrove-shrimp systems don't require the use of groundwater as the trees lining each pond maintain salt levels. They also help to hold sediment, protecting farms from erosion and holding an incredibly delicate coastline together.

"This coastline, within 50 years it will be gone. It will be all eroded," Wyatt said. "So [small-scale farmers] have no choice. Either they continue as they are and they lose this land because it's subsiding and because of sea level rise or they turn to integrated mangrove shrimp systems."

With nothing left and a family to feed, Hung signed up with the MAM project after the 2016 floods. The government assigned him a new plot of land under a conservation program that requires any farming to meet environmental standards and prohibits the clearing of trees.

But according to Wyatt, it is rare for smallholders to make such a big change unless they have hit rock bottom. Pushed by economic hardship, many small-scale shrimp farmers still choose to farm in an intensive way because of the higher yield. The country so far has an estimated 124,000 acres in integrated mangrove-shrimp farms.

Still, the IUCN maintains that integrated shrimp farming is the most realistic solution for both the environment of the Mekong Delta and the long-term financial stability of the region's small-scale farmers.

Though the yields are far lower than for conventional shrimp, organic shrimp can be sold for higher rates. Plus, under MAM, no labor or upkeep is required as the shrimp grow, and the risk of disease is minimal, which averts costly investments in water treatment, medicines, probiotics, and vitamins. "Most of what we earn is profit as we don't have many up-front costs anymore," Hung said.

After losing everything, this stability alone is enough to keep Hung working with MAM. "I know we won't ever have to go from rich to nothing in a night anymore," he said. "Before, the yield was good but things were precarious. One year you would be raking in money, and the next you would lose everything over a few different degrees of salt or a stray wind."

Super Intensive Farming for Large Operators

While the IUCN promotes integrated shrimp farming as ideal for small-scale farmers, it doesn't necessarily make practical sense for all businesses in Vietnam's shrimp industry. According to the organization, there is a future for intensive shrimp farming in this country, but only on a very large, industrialized scale, in well-contained facilities, and in regions of the Mekong that are not in urgent need of mangrove coverage.

Vietnam-Australia JSC, a foreign-invested shrimp farming enterprise with initiatives all over Vietnam, is pioneering this so-called super intensive approach by moving shrimp ponds out of the natural environment and into glass houses under tightly controlled conditions. "In our opinion this is the only way you can do intensive shrimp," Wyatt said.

According to VietnamNet, the output per hectare of these farms could be 10 to 15 times higher than that of traditional, small-scale intensive farms, an important factor given government targets to grow the shrimp industry and raise exports. But barriers to their development remain. While most of the delta's shrimp farms are smallholder-owned, there are several larger state-owned and private corporations along the Mekong coastline that hold long-term 15- or 20-year investment licenses. Wyatt said he'd like to figure out how to convince these businesses to move into glass-house shrimp production.

As the interests of the state and its private partners align, Vietnam's shrimp industry is moving toward a more stable, sustainable method of production—albeit slowly. According to Wyatt, change is inevitable: Vietnam either has to change the way it approaches shrimp farming, or face the loss of hundreds of hectares of land.

This story originally appeared at the website of global conservation news service Mongabay.com. Get updates on their stories delivered to your inbox, or follow @Mongabay on Facebook, Instagram, or Twitter.

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