"I like to pan fry it, or bake it," said Anthony Giardenelli, owner of Otorongo Expeditions, a tour company that takes trips throughout in the Peruvian Amazon. "It's very tasty," he said by phone from his office in Iquitos.
Giardenelli has caught dozens of pacu fish each season as the floodwaters of the Amazon drive fish into the forest in search of food.
"They have evolved migrating in and out of flooded waters to eat fruit and nuts," Giardenelli said. "They are attracted to anything splashing. Rubber tree seeds are one of their favorites. They are very hard-wired to follow a plopping noise in the water."
Giardenelli says he has heard the sound of pacu cracking nuts under water from a boat on the surface. "It sounds like two pool balls clacking together," he added.
Experts believe the pacu could be spreading to these other waterways around the world by hobbyists who dump the fish overboard when they get too big for the home aquarium.
"It's a plant eater," said Stefan Tanner, an editor and translator at Amazonas Magazine. "If you release it in Denmark, it won't survive the winter. If you release it in Florida, it may swim for a long time. Will it reproduce? That's another question."