Here it inhabits the Paraguay (including the Pantanal), Paraná, Uruguay, Chapare, Mamoré and Guaporé River basins, and the drainage of the Lagoa dos Patos.

[2][8] Outside its native range, the golden dorado has been introduced to several southeast Brazilian river basins, notably Doce, Paraíba do Sul, Iguazu and Guaraguaçu.

[3] It is migratory in response to temperature, season and food sources, and moves upstream, typically about 400 km (250 mi), to spawn in the spring and summer.

[6] They are primarily piscivores, eating a wide variety of fish, but have also been recorded feeding on large insects, crustaceans and small vertebrates (for example, rodents, lizards and birds).

[3] At up to 30 cm (12 in) long, juveniles are aggressive mimics of Brycon hilarii in both general shape and color, often staying near schools of this frugivorous species to be able to surprise smaller prey fish such as Astyanax and Moenkhausia tetras.

Its aggressive behavior and initiative taking flies, paired with great fight energy, frequently going airborne in the attempt to loosen itself from the hook, make this species a true game fish.

Anglers make use of either very slow or very fast movement of the flies to spark attacks by the dorado, depending on the region and season, denoting gregarious behavior and an ambush feeding strategy.

Due to the dorado's very sharp teeth, anglers use steel wire or fluorocarbon monofilament bite tippets to prevent the fish from cutting the line.