High-quality seed dispersal by fruit-eating fishes in Amazonian floodplain habitats.

摘要: Seed dispersal is a critical stage in the life history of plants. It determines initial pattern juvenile distribution, and can influence community dynamics evolutionary trajectories individual species. Vertebrate frugivores are primary vector seed tropical forests; however, most studies focus on birds, bats monkeys. Nevertheless, South America harbors at least 200 species frugivorous fishes, which move into temporarily flooded habitats during lengthy flood seasons consume fruits that fall water; yet, we know remarkably little about quality they effect. We investigated activities two large-bodied, commercially important fishes (Colossoma macropomum Piaractus brachypomus, Characidae) over 3 years Pacaya-Samiria National Reserve (Peru). assessed diet these season, conducted germination trials with seeds collected from digestive tracts, quantified fruit availability. In laboratory, fed to captive Colossoma, proportion defecated by adult fish, used additional experiments. Our results indicate Colossoma disperse large quantities up 35% trees lianas season. Additionally, germinate after floodwaters recede. Overexploitation has reduced abundance our focal fish species, as well changed age structure populations. Moreover, older more effective dispersers than smaller, fish. Overfishing, therefore, likely selects for poorest dispersers, thus disrupting an ancient interaction between their agents.