Synthesizing Multiple Long-Term Datasets to Test Flow Ecology Relationships for Fishes - Workshop Active

River ecosystems support a wide diversity of biota, including thousands of fish species, which are variously adapted to the dynamic environments provided by flowing-water habitats. One of the primary ways that human activities diminish the biological capacity of rivers is by altering the natural hydrologic variability of river systems through regulation and diversion of streamflow for other uses.  Managers may be able to avoid some of the worst effects of flow management on aquatic biota if we understand the mechanisms by which streamflow components, such as unusually high and low flow events, affect populations (e.g., by influencing recruitment and mortality).  Numerous past studies have described correlative associations of flow variability (or alteration) and ecological condition, but inconsistent and context-dependent results have limited our ability to assess support for broadly predictive hypotheses. 

This Powell Center working group will use a diverse set of long-term datasets to test hypothesized relations between riverine flow components and fish population dynamics. By analyzing time-series of fish population observations along with year-specific streamflow data, the group will assess support for specific hypothesized effects of flow variability, means, and extremes on fish populations (1) in differing geomorphic and climatic contexts, and (2) with respect to species that differ in life history and ecological traits. We expect to identify likely mechanisms linking flow regime components to fish population dynamics, initiate tests of these hypotheses using alternative analytical approaches and response variables, and help define the direction of flow ecology research over the next decade.  











Principal Investigator(s):

Mary C Freeman (Athens Field Station, PWRC)

Annika W Walters (Wyoming Cooperative Fish and Wildlife Research Unit)

Keith B Gido (Kansas State University)

Seth Wenger (University of Georgia)