Protecting One of World's Largest Freshwater Fisheries, One Village at a Time

When you hear the word “fishery,” certain images may come to mind: ocean trawlers far from shore, sharks caught in nets, beachside fish markets. But today on World Fisheries Day, I’d like to draw your attention to a different kind of fishery — the freshwater kind.
According to the IUCN, inland fisheries represent more than one-quarter of global fisheries production every year. Over 68% of these are located in developing countries.  Millions of people depend on freshwater fisheries for their livelihoods, yet these ecosystems face numerous threats.
Cambodia’s Tonle Sap Lake is a prime example. The largest freshwater lake in Southeast Asia, the lake and connected river system is an ecological wonder. Twice a year, the Tonle Sap River changes direction, feeding into (or draining from) the lake, depending on the time of year.
During the wet season, the lake doubles in size, flooding the nearby forest. These submerged trees serve as excellent breeding grounds for fish — one reason the Tonle Sap and the connected Mekong River make up one of the most productive freshwater fisheries in the world. Three million people depend on the Tonle Sap for their main source of protein.
Last week I had the opportunity to visit Acol, a floating village on Tonle Sap Lake. The people living here, and in dozens of other villages on the lake, don’t just live near fish, they live because of fish. In their brightly painted houses miles from the lake’s shores, floating village residents have literally adapted their entire way of life in order to be closer to their main source of livelihood. I saw floating markets, floating hair salons — even a floating gas station.
Yet the Tonle Sap’s productivity is at risk. Over the last 50 years, most of the flooded forest has been cleared, largely for fuelwood. A recent study estimated that pristine flooded forest can produce more than 17 times more fish per hectare every year than that same area after the forest has been cleared.
Dam construction on the Lower Mekong poses another threat to fish production by increasing sedimentation in the water, altering water levels and blocking fish access to the lake. Research indicates that climate change will cause additional impacts on the lake’s productivity by shifting the wet and dry season fluctuations that have been functioning for millennia.
When it comes to solving the myriad of challenges faced by the people dependent on the Tonle Sap, there is no silver bullet. The threats to the lake’s productivity are inherently interconnected and complex. The solutions must be, too.
Though wide-ranging in scope, most of CI’s activities on the lake aim to restore fish populations while helping community members become less dependent upon these fish. Some of our projects include:
  • Working with communities to establish and clearly mark the borders of fish sanctuaries in areas of the Tonle Sap that are especially important for fish breeding. As fish breed in these restricted areas, they will spill over into areas where fishing is allowed.
  • Paying some fishermen to monitor wildlife, including species like the hairy-nosed otter, which is classified as Endangered by the IUCN Red List of Threatened Species. Not only are these community wildlife monitors helping to shed light on the current state of some of the Tonle Sap’s most important and charismatic species, but receiving a salary from these activities means they don’t need to fish as much to earn an income.
  • Training village women in the production of prahok, a fermented fish paste that is widely used across Cambodia. Through the training course, the participants learned to produce the paste in a more hygienic way; for example, they now wear gloves and face masks while cutting up the fish. The result is a higher-quality product that can be sold for a greater price than before.
  • Providing fuel-efficient stoves to floating village households. Not only do these stoves use less wood than previous models (meaning there is less need to cut down the flooded forest), but they also reduce the amount of time needed for smoking fish and are better for respiratory health.
As our boat puttered around Acol and the two nearby villages, it seemed that everywhere I looked there was evidence of a CI project. Indeed, since the construction of CI’s floating office out on the lake a few years back, our hard-working local staff have become a known and trusted presence in these communities — and their efforts, though sometimes slow to catch on, are working.
The next step will be to expand this work into new floating villages, bringing us closer to securing the future of this crucial fishery for the millions of people who rely on it.
Molly Bergen is the senior managing editor of Human Nature.