A freshwater giant is a boon to Bolivian fishers, but an unknown for native species

A freshwater giant is a boon to Bolivian fishers, but an unknown for native species

  • Paiche or arapaima (Arapaima gigas) was introduced in Bolivia in 1976 by accident from Peru, and though initially rejected as an exotic species, is today prized by local fishers as a boon to the economy.
  • There’s no research on the potential damage caused to riverine ecosystems in the Bolivian Amazon region due to the arrival of paiche, but native fish species have disappeared in some areas where the freshwater giants thrive.
  • The Bolivian government has not classified paiche as an invasive species, with some official studies recommending controlling rather than eradicating its population.
  • Paiche fishing has also been encouraged as an economic boon to rural communities, where the species accounts for up to 70% of fishers’ catch.

Encountering his first paiche was such a surprise for Víctor Peñaloza Lurici that he can still recall the event back in 2016. He was 16 years old at the time. Now, at the age of 22, he’s become an expert at catching this new giant fish of the freshwater scene in Bolivia’s Amazonian region. When asked what it’s like to catch paiche, Peñaloza Lurici says it’s difficult and risky because of how large, alert, and patient the fish are. The important thing, he says, is that this work has become the mainstay of his family’s livelihood.

In the last 15 years, paiche (Arapaima gigas), also known as arapaima or pirarucu in other parts of the Amazon, has revolutionized the lives of communities living along the rivers that crisscross the Bolivian Amazon, despite the problems it represents as a non-native species. The Bolivian government still considers paiche to be an introduced species, rather than an invasive one, as more studies are needed to determine which varieties of fish are at risk due to its presence.

According to the project Peces para la Vida or “Fish for Life,” financed by the Faunagua Foundation and other entities, paiche were first observed in Bolivia in 1976, despite being native to more northern areas of the Amazon such as Brazil and Peru. Heavy rains caused pools to overflow at a paiche hatchery at Lake Sandoval near Puerto Maldonado, the capital of Madre de Dios department in Peru, and the juvenile fish were swept into the Madre de Dios River, a tributary of the Amazon that flows through Bolivia.

Paiche have thrived in Bolivian waters amid an absence of natural predators. They grow here to impressive sizes of more than 3 meters (10 feet) in length. As a result, they’ve spawned many stories and legends in the region. The species continues to expand its range by an estimated 33 kilometers (20 miles) per year, according to Paul Van Damme, director of the Faunagua Foundation.

The presence of paiche in Bolivia has become a paradoxical case of invasion by an exotic species, for the fish is threatened due to overfishing in its natural habitats in Peru and Brazil.

The extent of paiche’s impact on native species of flora and fauna in the Bolivian Amazon remains unknown. Image courtesy of Faunagua Foundation.

In Bolivia, paiche now inhabit the Abuná, Madera, Orthon, Madre de Dios, Beni and Yata rivers. They’ve also been found in the Mamoré and Itenéz rivers in the department of Beni, near Brazil, Van Damme said. This means the fish has managed to easily cross from west to east.

After taking over the Madre de Dios region, paiche also found in the streams and lagoons of northern Bolivia favorable ecological conditions for their reproduction and eventual proliferation in the interior of the country. Paiche lay their eggs along the riverbanks and are successfully reproducing in tributaries of the Bolivian Amazon’s biggest waterways.

The fish can grow up to 3.5 m (11.5 ft) and weigh more than 300 kilograms (650 pounds). Their meat is considered very delicious, and it’s estimated that 80% of the fish sold in the northern departments of Pando and Beni are paiche, although often marketed under the names of native species such as surubí catfish (Pseudoplatystoma spp.) or pacú (Myleus pacu).

The boom in the northern Amazon

The Faunagua Foundation is an NGO that has worked since 2014 on research and management of Bolivia’s water resources and wetlands. It estimates that about 4,000 metric tons of paiche are caught in the rivers of the Bolivian Amazon each year. This, according to Van Damme, means that paiche accounts for 70% of the market in Bolivia’s main fishing departments of Pando and Beni. This is why the species has become a key source of livelihood for many Bolivian families.

“Paiche occupies a very important place in the value chain and has displaced native species in fishing, such as surubí, pacú and others. Now, paiche makes up 70% of the catch for fishermen because it is easier, has more meat, and no bones. Paiche has changed the value chain, and there are fishermen who fish for this species exclusively,” Van Damme told Mongabay Latam.

The paiche boom has changed the lives of residents in Riberalta, a municipality in the department of Beni, located 950 km (nearly 600 mi) east of the capital, La Paz. In Riberalta, a city the size of the Gulf kingdom of Qatar, fishing for paiche has become the main economic activity, on par with farming Brazil nuts, a seasonal activity that’s highly profitable due to the quality of the nuts grown here.

El paiche representa el 70 % de lo que pescan en la Amazonía Boliviana. Foto: Sernap.
Paiche represents 70% of the catch for fishers in the Bolivian Amazon. Image courtesy of SERNAP.

Is it possible to stop the expansion of paiche in Bolivia? Van Damme’s answer is a categorical “No.” Could the paiche have negative impacts on native fish? “There are no conclusive answers here,” he said, “but we think that we can strike a balance between sustainable use and the protection of native species that are important for subsistence fishing.”

Landlocked Bolivia lacks a fishing culture, and hence the national diet is dominated by red meat. With no route to the sea, the country relies on its Amazonian rivers and highland lakes as key sites for fishing, but with some limits. It’s estimated that Bolivians consume an average of 2.6 kg (5.8 lbs) of fish per person per year, according to a 2017 study by the Ministry of Rural Development. National and regional authorities say they aim to boost fish consumption to 5.1 g (11.2 lbs) per capita annually. Half of the country’s current fish consumption consists of imports, mostly from Argentina and Peru.

Since 2011, paiche fishing in northern Bolivia has tripled annually, according to Van Damme. The species represents about three-quarters of a professional fisherman’s income, on average.

Despite paiche an exotic species, if managed properly it could also become a powerful tool to halt deforestation and land-use change in the Amazon, two major problems in Bolivia, according to Van Damme.

All of the fish gets used: its meat, skin, and even its tongue. The meat is sold in Bolivia’s main cities; at markets in La Paz, it can fetch the equivalent of $8.70 per kilo, or $4 per pound.

Paiche skin is used to make handbags, wallets and other accessories. The raw material is worked in cities and towns in eastern Bolivia, and the finished products are exported. The fish’s rough tongue is dried and used as sandpaper or a food grater, and can also be ground for use as a medicine to treat intestinal parasites, according to traditional culture.

El paiche se ha convertido en la opción más rentable para los pescadores en la Amazonía de Bolivia. Foto:
Paiche has become the most profitable option for fishers in the Bolivian Amazon region.

A Bolivian micro enterprise called Curupaú, based in the city of Cochabamba, sees paiche skin or leather — which is dried, salted, tanned, and processed — as a possible gold mine for export in the form of goods like boots, shoes, handbags, book covers, wallets, belts, and more.

In the city of Riberalta alone, 70,000 kg (154,000 lbs) of paiche are caught every month, and 15% of that weight consists of skin. According to Lincon Zapata, owner of Curupaú, demand for the leather has led Indigenous communities to deliver the fish with its skin and scales included. This means higher profitability for suppliers and more raw material for artisans, and also keeps the meat better preserved. According to Zapata, it’s a win-win all around.

Despite the economic benefits that paiche represents for many Bolivian fishers, its impacts on biodiversity are little studied, and there’s a lack of government regulation and monitoring of the issue.

Lack of research

Selin Trujillo is the president of the Federation of Fishermen, Traders and Fish Farmers of the Northern Amazon of Bolivia. He said that when paiche was first discovered in the waters of northern Bolivia, fishers there were frightened because they didn’t know what it was. The species doubled in number in 1995 he said, and eventually native species could no longer be fished because there was only paiche.

“Now, the paiche is a blessing for fishermen, but several species have disappeared,” Trujillo said. “Although we don’t know if it’s because of the paiche, since it could also be due to illegal gold mining.”

Van Damme said there’s no research in Bolivia to corroborate which, if any, native species were wiped out by the expansion of paiche. However, what’s certain is that one variety, the tucunaré (Cichla ocellaris), a fish that used to inhabit the Paraguá River, is no longer seen in the area.

“We assume that the impact of the paiche is quite large because it is a predator that eats native fish,” Van Damme said. “We have opened their stomachs and seen some, but in order to demonstrate the impact, we have to show the structure of the [native fish populations] before and after the arrival of paiche. We have data from some rivers, but we have not been able to look back [historically].”

Van Damme cited studies he carried out 20 years earlier in the Paraguá River, when there were no paiche at the time. “Now we know that there are, and it would be interesting to analyze what is happening. They say that there are no more tucunaré, and we assume that the paiche devastated it.”

pesca yanayacu perú
The paiche arrived in Bolivia through Peru, via the Madre de Dios River. Image courtesy of Instituto del Bien Común (IBC).

The paiche is a key predator in Bolivian rivers that have slow currents and in the bends of lakes in the northern Amazon. It’s known for eating just about anything that fits into its enormous hooked jaws, in addition to swallowing seeds, leaves, stones and mud. Experts agree that it’s a voracious carnivore and destructive to the native ecosystem.

In 2017, the Bolivian government financed a study on the management of paiche in Amazonian waters with the participation of the Faunagua Foundation. The research was carried out in the Beni and Madre de Dios rivers with the objective of taking advantage of paiche populations and finding ways to reduce their negative impacts on the ecosystem.

It delved into the diet of the fish by collecting and dissecting them to study the contents of their stomachs. A total of 253 paiche stomachs were analyzed, of which 177 specimens yielded stomach contents (97 were female fish and 70 male).

“It was found that the diet is mainly composed of fish, plant matter, and invertebrates. Fish was the only item categorized as primary,” the study says. It adds that the fish species most preyed on by paiche are those of the order Characiformes, scaly species that include piranhas.

The invertebrates found in the paiche stomachs came from the orders Coleoptera (beetles), Hemiptera (bugs like aphids and cicadas), and Decapoda (crustaceans). The study says “No significant differences in diet composition were observed between the different sizes and sexes.”

Another study was done by the Bolivian Ministry of Environment and Water, through the National Service of Protected Areas (SERNAP), which approved a paiche monitoring and use plan in Manuripi National Amazonian Wildlife Reserve, located in the department of Pando. The stated objective of the study was “mitigating the negative impact of paiche on the reserve’s native ichthyofauna, through controlled extraction and the integral use of its byproducts.”

Studies show that the paiche has omnivorous habits with a preference for fish, and that it’s an opportunist rather than a selective species. Image courtesy of Roxana Salas/Faunagua Foundation.

The SERNAP study cites the need to regulate the use of paiche and recommends controlling rather than eradicating the species, although it acknowledges that paiche has caused a decline in native fish since arriving in the Bolivian Amazon in 1976. This, the study says, could affect the “food security of the communities that depend on this resource.” Therefore, “the objective of the plan in the Manuripi reserve is to reduce the paiche population to a level that does not represent a threat to other species, while generating social and economic benefits for the area’s residents.”

Fernando Carvajal, a Bolivian researcher and expert in paiche management, said more research and partnerships are needed to determine the exact damage caused by this invasive species. Carvajal also cited Faunagua Foundation studies that suggest that paiche, being a carnivorous fish, is reducing the number of native fish in the rivers.

Federico Moreno, director of the Beni Autonomous University’s Center for Aquatic Resources Research (CIRA), said more research is needed to determine whether other native Amazonian fish species are threatened by paiche. He cited the example of the piranha, a fish that paiche prey on but that are still found in the rivers of northern Bolivia. Piranhas, he said, would be at imminent risk from the presence of the large freshwater predator.

“The case of the paiche is particularly interesting because the species has proven to be very vulnerable to extinction in its natural range in the Amazon, particularly in Peru and Brazil,” Moreno said. “On the other hand, in Bolivia, where commercial fishing is on a smaller scale, the fish has come to occupy an important segment of the value chain in the northern Amazon, which is why there is often talk of a boom in the sale of the species.”

El arapaima (Arapaima gigas) es un gigantesco pez que habita los ríos amazónicos Foto: Mongabay
The paiche is one of the world’s largest freshwater fish species. Image by Mongabay.

Van Damme said that for many Bolivian fishers, what was once an ecological disaster has become an economic bonanza. This was echoed by Jesús Justiniano, a fishing leader in the community of Trinidacito, in the department of Pando.

“We see paiche as a blessing,” Justiniano said. “Our lakes and rivers in Trinidacito have not changed much. In the Mentiroso Lagoon, paiche abound and there are other species as well. We do not want to exterminate them; they should be maintained because they are the livelihood of several families. You can catch just one paiche and you’re all set, whereas you’d have to catch many tambaquies [Colossoma macropomum] to survive.”

Justiniano said he doesn’t agree with calls to remove paiche entirely from Bolivian rivers. He added he doesn’t believe the invasive species harms the native fish, and that it’s instead “another resource [we can use] to live.”

It’s these divergent views that show that the presence of paiche in Bolivia is a true paradox. In its native habitat, overfishing is driving the fish to extinction. In Bolivia, meanwhile, where other species may very well be disappearing because of its presence, paiche is now a driving force of the economy.

Banner image: Paiche can reach more than 3 meters (10 feet) in length. Image courtesy of SERNAP.

This story was reported by Mongabay’s Latam team and first published here on our Latam site on Sept. 12, 2022.

This story first appeared on Mongabay

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