Relationship Between Base Flow and Fish Communities within Karst Spring Complexes

Numerous spring complexes provide base flows within the Edwards Plateau region of Texas, and support endemic fishes that are associated with the spring complexes (i.e., spring-associated fishes).  Purpose of this study was to assess the relationship between base flow magnitude and the number of spring associated species, their abundance, and densities. Differences in spring-associated fish richness, relative abundances, and densities along a base flow gradient were detected.  Richness, densities, and relative abundances of spring-associated fishes were non-linearly related to base flow, suggesting that spring complexes have a level of buffering capacity against base flow reductions.  Predictive models generated in this study can be used to evaluate spring-associated fish community integrity within the Edwards Plateau Region and to predict future changes in Edward Plateau spring complexes related to increases in groundwater extraction.