Farm-raised, fresh-water Paiche have journeyed from the murky Amazon to restaurants in cities from Houston to Paris. The low-fat, mercury-free white fish may soon be available at select U.S. grocery stores.

Paiche, which at up to 220 pounds (100 kgs) is one of the world's largest fish, fed spear-fishing indigenous peoples for centuries. But their numbers dwindled when nets were introduced in the Amazon and the region's cities grew and developed.

Paiche Amazone, a company backed by Peruvian mining and cement conglomerate the Hochschild Group, hopes to save the species from extinction by breeding organic, farm-raised fish for export and releasing some back into the wild.

"What really got me most interested was the effort to try to control the commercial fishing of an endangered species," said Jose Duarte, chef at the Italian Peruvian restaurant Taranta in Boston, Mass.

"It's a really good fish ... it's almost like a sea bass with a better texture," said Duarte, who was preparing a daily special of pan-seared Paiche with panca peppers and scalloped potatoes.

The Monterey Bay Aquarium has listed Chilean sea bass, also known as Patagonian toothfish, as a fish to avoid because of unsustainable fishing practices and potentially high levels of mercury.

Paiche Amazone is not yet profitable. It expects to export $3 million worth of frozen Paiche this year, up from $500,000 sold in 2011, when the fish first hit global markets.

Paiche, a carnivorous, air-breathing giant also known as Arapaima, can be cut into generous, bone-free fillets. Chefs say it is easy to sear and very difficult to burn due to its high collagen levels.

Restaurants such as Robert at the Museum of Art and Design in New York, Area 31 in Miami and Latin Bites in Houston now serve Amazone's Paiche. It is also sold in Spain, France and Italy.

"The idea is to have a supply for global gourmet markets," said Isaac Gherson, CEO of Paiche Amazone. "We don't want Paiche to become a type of commodity -- that would mean exploiting the species again."

Paiche is also earning a place in Lima, an emerging culinary capital, where celebrity chef Pedro Miguel Schiaffino grills Paiche steaks and marinates the fish with lime to make ceviche, a Peruvian staple, at his upscale Malabar restaurant.

Paiche Amazone sells the fish in the United States through ArtisanFish, a Florida-based wholesaler that markets hormone-free, premium seafood with the goal of protecting the environment.

ArtisanFish has negotiated an agreement to sell Paiche in a U.S. retail chain, said founder Adrian Burstein. He declined to name the retailer due to contract provisions but believes Paiche will have a growing presence in U.S. cuisine.

"It was hard to replace Chilean sea bass with an alternative that has similar qualities but is truly sustainable," said Burstein. "Now you have an option -- Paiche is that option."

(Reporting By Caroline Stauffer; editing by Patricia Reaney)

• A Permanent Economic Emergency