Goliath catfish spawning in the far western Amazon confirmed by the distribution of mature adults, drifting larvae and migrating juveniles | Laboratório de Ictiologia – Universidade Federal do Rio Grande do Sul

Ronaldo B. Barthem, Michael Goulding, Rosseval Leite, Carlos Cañas, Bruce Forsberg, Eduardo Venticinque, Paulo Petry, Mauro L. de B. Ribeiro, Junior Chuctaya & Armando Mercado

We mapped the inferred long-distance migrations of four species of Amazonian goliath catfishes (Brachyplatystoma rousseauxii, B. platynemum, B. juruense and B. vaillantii) based on the presence of individuals with mature gonads and conducted statistical analysis of the expected long-distance downstream migrations of their larvae and juveniles. By linking the distribution of larval, juvenile and mature adult size classes across the Amazon, the results showed: (i) that the main spawning regions of these goliath catfish species are in the western Amazon; (ii) at least three species—B. rousseauxii, B. platynemum, and B. juruense—spawn partially or mainly as far upstream as the Andes; (iii) the main spawning area of B. rousseauxii is in or near the Andes; and (iv) the life history migration distances of B. rousseauxii are the longest strictly freshwater fish migrations in the world. These results provide an empirical baseline for tagging experiments, life histories extrapolated from otolith microchemistry interpretations and other methods to establish goliath catfish migratory routes, their seasonal timing and possible return (homing) to western headwater tributaries where they were born.

Article: http://www.nature.com/articles/srep41784

(A) B. vaillantii (piramutaba in Portuguese, pirabutón in Spanish); (B) B. rousseauxii (dourada in Portuguese, dorado in Spanish); (C) B. platynemum (babão in Portuguese, mota flemosa in Spanish); (D) B. juruense (zebra in Portuguese, zebra in Spanish); (E) Dorado migrations exploited by fishermen. The Santo Antônio Dam on the Madeira River now drowns the Teotônio Rapids (shown here) where B. rousseauxii (species in photo) and B. platynemum were previously exploited and easily detected when migrating. Photos by M. Goulding.

(a) Sites investigated by the authors and others from published data. (b–e) Locations of mature goliath catfishes by species. Figure was created by authors with ArcGIS for Desktop Advanced 10.2, MapPublisher 9.6 tool inside Adobe Illustrator CC, and Adobe Illustrator CC, 2.0.