Life in a Brazilian floodplain river

Millions of people around the world depend on highly productive floodplain rivers for food and recreational fishing. The So Francisco River, a river drainage southeast of the Amazon River, has a major fisheries on migratory fishes that crashed in the 1990s. Many believe that the fisheries collapse was due to a lack of floods. However, the dependence of So Francisco River migratory fishes on floods is poorly understood. In this book, we present scientific-based data to aid in understanding the life history of migratory fishes, particularly in relation to floods. We radio-tracked two species to characterize their migrations and spawning. We also monitored radio-tagged fish movements to test the hypothesis that the cool hypolimnetic discharge from Trs Marias Dam blocked their upriver migration. Further, we used ichthyoplankton sampling of fishes, and hydrological, and economic data to develop a conceptual model for supplemental water releases from the Trs Marias Reservoir to restore successful spawning and the downstream fisheries. The contents of this book will be of interest to fish biologist, fisheries managers, and graduate students.