Patterns of Fish Diversity and Community Structure Along the Longitudinal Gradient of the Kiamichi River in Southeastern Oklahoma

In riverine systems, patterns of fish community structure and diversity show changes along the longitudinal profile, i.e., from upstream to downstream. Previous research has shown longitudinal patterns may include changes in various measure of species diversity, such as species richness and species abundance, and patterns of species accumulation that often include species addition and/or species zonation. We used seines and electrofishing gear to sample the small-bodied fish community along the longitudinal gradient of the Kiamichi River in southeastern Oklahoma. Our objectives were to look for longitudinal patterns of (1) species diversity and (2) community structure. We sampled at 11 sites during 2012-2013. We standardized sampling based on 30 minutes of electrofishing and 200 meters of seine hauls at each site. We also used experimental gill nets to contribute to the baseline information of large-bodied fishes in the Kiamichi River. A total of 9,620 fish were collected representing 54 species and 15 families. The Kiamichi River showed increasing species diversity along the longitudinal gradient, as well as patterns of species addition. Further, we found four distinct groups of fish along the longitudinal gradient, including ubiquitous species, widespread but scattered species, species restricted to downstream sites, and rare species. ©2015 Oklahoma Academy of Science