Why We Must Protect Freshwater Fish

Rivers and lakes are under threat—and so are millions that fish in them.

This story appears in the April 2017 issue of National Geographic magazine.

Hundreds of millions of people worldwide would lack their prime source of protein without freshwater fish. Yet the lakes and river systems that supply them are often overlooked by policymakers, who focus sustainability efforts instead on ocean species.

Marine fisheries tend to be commercial operations, while freshwater fishing is almost exclusively a means of subsistence. “Most freshwater fish catches don’t enter the global trade economy, so they draw less interest,” says University of Wisconsin–Madison zoologist Peter McIntyre.

McIntyre recently conducted a global analysis of riverine fisheries—and the threats they face—and determined there is an urgent need to safeguard these regions. He and his team found that 90 percent of the global freshwater catch comes from ecosystems that are stressed by “above average” pollution, dambuilding, and invasive species.

Nowhere are these challenges more potentially damaging than within Southeast Asia’s multicountry Mekong River system—the world’s biggest freshwater fishery. There, says McIntyre, many people rely on catfish and other river species as a critical source of dietary protein that could not easily be replaced.

McIntyre’s research does not point to a “sky is falling” scenario, he says, but it is clear now that “the places getting hammered the hardest are the places where we have the most to lose.”