Locals Are Saving an Enormous Tropical Fish From Extinction
Three decades ago, commercial overfishing decimated populations of the arapaima—the largest scaled freshwater fish in the world—in the meandering Juruá River in a remote area of Brazil’s western Amazon.
Now scientists report that among 83 lakes along a 310-mile stretch of the Juruá, populations of arapaima, an air-breathing fish that can grow more than 10 feet long and weigh more than 400 pounds, rapidly rose by several orders of magnitude when local communities controlled subsistence fishing and conservation efforts. Counts remained low in lakes where fishing remained unrestricted.
Local management has improved the supply and security of a key source of protein for these small communities of four to 30 households while increasing annual income from legal sales of arapaima to about $1,050 per household, according to the study.
It’s money that these impoverished families can put toward health care, education, internet access, and other quality-of-life improvements, said ecologist Carlos Peres of the University of East Anglia. Peres coauthored a paper published in the journal Nature Scientific Reports that documented the impacts of the community-led management.
“They are semi-subsistence, extractive communities,” he said. “They’re not Indians, not indigenous as you would define a Navajo Indian in the U.S. Genetically and culturally, they are basically hybrids of Brazilians of European descent and indigenous peoples.”
“A lot of their extractive practices were inherited from Indians—they are very skilled at fishing with bow and arrow, for example,” he added. “But they are very integrated into the Brazilian mode of thinking: They watch television. They vote. They exercise their citizen rights.”
Peres thinks the project may be a good model for conserving biodiversity and addressing poverty in other freshwater ecosystems. “It’s comanagement because you have a government conservation or resource management agency,” he said. “But in these remote parts of the Amazon, the local stakeholders are the only people that are really there and the only people that really matter.”
On average, each lake managed by residents for subsistence fishing had about 305 arapaima, while those that remained open to unrestricted commercial fishing had just nine, according to the report.
Based on local counts by experienced fishers, the researchers modeled total arapaima populations for the lakes monitored in the project. They estimated that an 828-acre lake called Rato, managed by the community of Caroçal, contained 665,000 arapaima. In contrast, in a comparably sized lake called São Sebastião, which remained open to unrestricted commercial fishing, the population was 16,000.
“What we’re documenting, I think for the first time in a freshwater fishery, is that if you move these lakes from an open-access ‘tragedy of the commons’ to the stewardship of a local community, and you regulate the fishing by bringing in the community-based management, these stocks just go through the roof,” said Peres. “It’s like if you put your money in a bank account, and it earns not 3 or 4 percent a year but 200 or 300 percent a year.”
According to the paper, agreements negotiated by local communities and commercial fishers in the early 1990s established which lakes would be open to or protected from commercial fishing. “These were very serious conflicts in the past; people used to get killed,” Peres said. “Now, all of those conflicts have been resolved,” and the conditions are good for effective community-led management of the fish stocks.
“I find this an amazing and quite unusual case,” he said. “When we started doing this, we never meant this to be an integrated conservation-development project, but that is what it turned out to be.”