Wetlands offer habitat to various fish species, which include numerous endangered and threatened species. Water quality parameters play a vital role in shaping fish assemblage composition in any water body including wetlands. However, the wetland fish community structure and their interactions with water quality parameters have historically been understudied compared to other kinds of waterbodies in Arkansas.
This study assessed fish assemblage and their relationship with water quality parameters across 30 wetland sites in Arkansas, USA. Data for this study were collected during the summers of 2024 and 2025. The sampled wetlands consisted of five agricultural ditches, twenty NRCS (Natural Resources Conservation Service) established WRE (Wetland Reserve Easements), and five natural/minimally disturbed wetlands of northeastern Arkansas. A total of fifty-one fish species and 41,909 individuals were recorded throughout the study period. The level of species diversity (measured through the Shannon-Wiener diversity index), dominance (estimated by Simpson’s dominance index), species richness (calculated through Margalef species richness index), and evenness (quantified through Pielou evenness index) varied across the wetland types, although the differences were not statistically significant. Temperature, Oxidation-reduction potential and pH showed significant differences across three kinds of wetlands. However, dissolved oxygen, conductivity, total dissolved solids and salinity differences were not statistically significant. The principal component analysis showed the water quality profile of each wetland while canonical correspondence analysis showed the relationship between fish species and water quality parameters. This study provides essential baseline information on the relationship between the water quality parameters and fish assemblage in the wetland habitats of Arkansas.