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Tributaries as biodiversity preserves: An ichthyoplankton perspective from the severely impounded Upper Paraná River

February 18, 2019
  1. Conservation of fish assemblages in severely impounded rivers has often focused on providing longitudinal and lateral connectivity along the main stem. Less attention has been given to tributaries, some of which remain unimpounded.
  2. This study shows that the biodiversity of ichthyoplankton in tributaries to the largest reservoir in the Paraná River, Brazil, is similar to that of tributaries of the few remaining unimpounded stretches of the Paraná River.
  3. Annual and seasonal variability in discharge within and among tributaries attracts and supports a diverse mix of species in each spawning season.
  4. Tributaries enrich the fish biodiversity of the entire system by providing a variety of environmental conditions, access to spawning habitat, refugia for early life stages, and by promoting ecological heterogeneity. Thus, tributaries can mitigate the adverse influence of an impounded main stem.
  5. Tributaries also support populations of endangered and threatened species. A focus on tributaries offers conservation alternatives that are more feasible given the scale and large number of impoundments constructed on the main stem.
  6. Conservation in the main stem may focus on maintaining passage through dams and access to large floodplains. Conversely, in tributaries conservation may focus on managing the quality of inflows from catchments, preserving suitable instream habitats and flows, and preserving access to smaller but more numerous floodplains.
Publication Year 2019
Title Tributaries as biodiversity preserves: An ichthyoplankton perspective from the severely impounded Upper Paraná River
DOI 10.1002/aqc.3037
Authors Patrícia S. da Silva, Leandro E. Miranda, Sergio Makrakis, Lucileine de Assumpção, João Henrique Pinheiro Dias, Maristela Cavicchioli Makrakis
Publication Type Article
Publication Subtype Journal Article
Series Title Aquatic Conservation: Marine and Freshwater Ecosystems
Index ID 70227938
Record Source USGS Publications Warehouse
USGS Organization Coop Res Unit Atlanta