Measuring 10 feet (3 meters) long and weighing in at more than 400 pounds (180 kilograms), it's hard to imagine that the arapaima, the largest fish in the Amazon River basin, could ever go missing.

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A fish larger than a man, tasty as well as beautiful, the freshwater pirarucu is a favorite with poachers in a lawless part of the Amazon jungle where Brazil, Peru and Colombia meet. Prized for its ...

Piranhas are among the most deadly creatures in the water, with razor-sharp teeth capable of slicing flesh easily, but a fish in the Amazon River basin has developed a "bulletproof vest" to protect ...

Amazon basin fish species living in lakes, floodplain forests and river systems need a high degree of connectivity to stay genetically diverse and healthy, but this connectivity is threatened by ...

MAMIRAUÁ RESERVE, Brazil — On this stretch of the Amazon River, you don't need a fish finder to locate the pirarucu, one of the world's largest freshwater fish. The splashing gives them away. Like the ...

Researchers discover that overexploited fish are long-distance seed dispersers. The giant tambaqui (Colossoma macropomum) in Manaus Fish Market, Brazil. Photo by: Thorke Østergaard. A fruit in the ...