The giant Arapaima fish, which can grow up to 3 meters long, has nearly disappeared in Brazil until local communities joined conservation efforts for this largest freshwater fish on Earth.
Just over a decade ago, the Arapaima (scientific name: Arapaima gigas), a fish that can reach lengths of up to 3 meters and weigh as much as 230 kilograms, commonly found in the Amazon River basin, faced extinction risk due to severe population decline caused by overfishing.
Fishermen catching an Arapaima fish in the Amazon River. (Source: National Geographic).
However, local conservation efforts have turned the situation around, leading to a significant increase in the Arapaima population.
According to research by Brazilian ecologist João Campos-Silva, in areas where communities adopted sustainable fishing practices, the Arapaima population has increased by 425% over the past 11 years.
The revival of the Arapaima species is a success story that can serve as a model for protecting other large aquatic species in the Amazon and globally, with local communities playing a crucial role.
Spanning an area nearly the size of the United States, the Amazons River basin in South America, with 60% of its area within Brazil’s borders, is home to tens of millions of people, including about 400 indigenous groups.
This basin is surrounded by thousands of rivers, hosting more fish species than any other river system on Earth.
As the largest freshwater scaled fish in the world, the Arapaima in Brazil is known as “pirarucu,” which means “red fish” in the indigenous Tupí language, referring to the distinctive color of its tail.
Hunting in lakes and swamps, the Arapaima can only dive underwater to hunt for 10 to 20 minutes before needing to surface to breathe through specialized swim bladders similar to lungs.
The Arapaima fish once faced extinction due to overfishing. (Source: National Geographic)
Having to surface for air makes the Arapaima vulnerable to hunting. A 2014 study found that demand for seafood had led to overfishing, causing severe population declines of this fish species.
At that time, the Brazilian government established a network of protected areas throughout the Amazon, with some states banning the fishing of Arapaima.
Successful Conservation
About 15 years ago, ecologist Campos-Silva began research along the Jurúa River, closely collaborating with residents of the São Raimundo community.
Based on fish populations, the community established sustainable fishing quotas, allowing the federal government to permit the harvest of 30% of adult Arapaima (over 1.5 meters long) in protected areas.
Most Arapaima spawn right after floodwaters rise and inundate the forests. When waters recede during the dry season, fish become trapped in isolated lakes and rivers. During this time, local authorities allow residents to fish.
Local fishermen catching Arapaima on a branch of the Amazon River. (Source: National Geographic).
These measures yielded almost immediate results. Thanks to their extremely fast growth rate, the Arapaima population has rebounded.
In addition to local residents earning more income, revenue from fishing is reinvested into schools, healthcare centers, and basic infrastructure in the community.
Scientists continue to gain deeper insights into the movements, ecosystems, and populations of Arapaima, including tagging and tracking them with radio waves.
For instance, they discovered that for a population of Arapaima to be considered healthy, there must be at least 30 individuals per square kilometer of floodplain.
Donald Stewart, a fisheries professor at New York State University, stated that community-based conservation methods have yielded even more spectacular results in Guyana, where the Arapaima population has increased tenfold since 2000.
A licensed Arapaima processing facility in Amazonas state, Brazil. (Source: National Geographic)
However, there are still many unmanaged areas in the Amazon where the Arapaima may face local extinction.
This scientist’s research indicates that there are still some distinct Arapaima species, and some of them remain critically endangered.
Nonetheless, the success of Arapaima conservation can serve as a model for protecting and managing populations of other giant fish species at risk of extinction worldwide.
