ABSTRACT: Throughout Amazonia, overfishing has decimated
populations of fruit-eating fishes, especially the large-bodied
characid, Colossoma macropomum. During lengthy annual floods,
frugivorous fishes enter vast Amazonian floodplains, consume
massive quantities of fallen fruits and egest viable seeds. Many
tree and liana species are clearly specialized for icthyochory,
and seed dispersal by fish may be crucial for the maintenance of
Amazonian wetland forests. Unlike frugivorous mammals and birds,
little is known about seed dispersal effectiveness of fishes.
Extensive mobility of frugivorous fish could result in extremely
effective, multi-directional, long-distance seed dispersal. Over
three annual flood seasons, we tracked fine-scale movement
patterns and habitat use of wild Colossoma, and seed retention
in the digestive tracts of captive individuals. Our mechanistic
model predicts that Colossoma disperses seeds extremely long
distances to favourable habitats. Modelled mean dispersal
distances of 337-552 m a