Antonio Menezes-A Critica / Reuters A port worker carries a paiche, the largest freshwater fish in South America, after 66 of the fish were confiscated from poachers transporting them to a market in Manaus, Brazil, on Sept. 17, 2008

Santiago Alvez remembers growing up in the Peruvian Amazon, hunting for game and fishing along the Tigre River and nearby oxbow lakes with his father and grandfather. Alvez, now 67, would go on to become a commercial fisherman, running ships that would ply jungle rivers for fish. His prized catch was paiche, one of the world’s largest freshwater fish, found in Peru’s Amazon and neighboring countries.

“There used to be paiches in all the rivers and lakes, but not any longer. There was no control, and we overfished. There are still paiche out there, but they are smaller, and you have to know where to look,” says Alvez.

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The paiche, also known as pirarucu or by its scientific name, Arapaima gigas, can grow up to 3 m and weigh up to 220 kg. It is often sought out for its tasty white meat. Barely changed from the Miocene epoch (which ended more than 5 million years ago), the living fossil is easy to catch with a harpoon or net because it has to come to the surface to breath. Other fish breathe underwater, taking oxygen from water through their gills.

The combination of taste and the ease with which it is landed nearly led to the demise of the paiche, which is included on a list of controlled species by the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES.

A decade ago, the paiche seemed to be doomed. However, the big fish is making a comeback thanks to efforts to reintroduce it into the wild and raise it through fish farming. Alvez is a pioneer paiche grower, having switched from fishing to fish farming in the late 1980s. He was the first to successfully breed paiche in captivity on a large scale. “Everyone thought I was crazy when I started keeping paiche in my ponds, but it worked. My paiches are being used to repopulate areas, and I am exporting them as far away as Japan and China,” where they are kept in ponds like koi, he says. “I know that we overfished, and now my goal is to restock the Amazon. I want there to be paiches in jungles like when I was a boy,” he says.

Alvez currently has 14 adult paiches, each about 1.8 m long, that he keeps as breeders. The females lay several thousands of eggs — although researchers have counted as many as 50,000 in the wild — and the fingerlings are closely guarded by the male after they hatch, forming a murky cloud around its head until they are big enough to swim away. Alvez removes the young after six weeks, when they are already around 20 cm long. They would be devoured by the adults if kept longer than that in the ponds.

He raises tilapia as paiche food, shying away from pellets developed by a government research center. Alvez says that while having to surface to breathe has hastened the paiche’s decline in the wild, it is a benefit in fish farming because many animals can be kept in relatively small, oxygen-scarce ponds.

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Local governments see fish farming using paiche as a potential boom industry. The regional government in Ucayali, in the eastern Amazon, is stocking lakes with paiche and encouraging its use in fish farming as an alternative to coca, from which cocaine is made. Regional president Jorge Velásquez says paiche could become a huge income earner for coca farmers switching to licit activities. “We are telling the coca farmers that we can help them install fish-farming ponds. One hectare of pasture for cattle produces 400 lb. [180 kg] of meat, but this same hectare can produce 20,000 lb. [9,000 kg] of fish in fish-farming ponds,” he says.

If cultivated under optimal conditions, paiches can reach up to 9 kg in less than a year, says Velásquez. Paiche is much easier to raise and grows much faster than better-known fish-farmed species, such as salmon or sea bass.

The idea of paiche farming is starting to catch on in a big way. Fish farming produced 465 tons of paiche in 2011, up from 52 tons the previous year and only 3.3 tons in 2009. It is now fourth in terms of farmed fish in Peru, after trout, tilapia and gamitana, sometimes known as tambaqui in English, another jungle fish, according to the Production Ministry.

Authorities are hoping for even bigger jumps in production thanks to the rapidly increasing interest in Peruvian haute cuisine. Paiche is now found in Peru’s five-star restaurants and is appearing on menus from Berlin to New York City and Tokyo.

The big jump in production and export of paiche fillet is attributable to one company, Amazone, located in the jungle town of Yurimaguas. Started in 2006 by the Pacasmayo cement company as part of an environmental plan to reuse pits from which it extracts materials, the project now has the capacity to produce up to 15 tons of paiche meat a month. It began exports in 2010.

In addition to cultivating fish for the market, Amazone has also partnered with local communities to return adolescent paiches to start repopulating lakes in the northern Amazon.

Gustavo Sakata, head of operations for the project, says Amazone has not only perfected paiche breeding in captivity but also discovered important elements of its feeding habits and reproduction along the way. Unlike similar fish, the female paiches deposit eggs several times a year, making it easier to maintain a constant supply for markets.

While the discoveries guarantee supply of paiches, the issue is generating demand. “My dream is that someday I can go to any major city in the world and paiche will be known the way salmon is known today. It is a dream, but we have only started, and I think the possibilities are limitless,” says Sakata.

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