A Comparative Study of the Ichthyofauna in Selected Streams on the Salt Plains National Wildlife Refuge in Oklahoma

This paper lists fishes and their abundances in seine collections from streams of the Salt Plains National Wildlife Refuge (SPNWR) in Oklahoma. We collected a total of 15 species and one hybrid. Dominant species included the cyprinids Cyprinella lutrensis, Hybognathus placitus, Notropis atherinoides, and the atherinid Menidia beryllina. Shannon-Wiener diversity (H') and evenness measures for sites located in upstream reaches were typically higher than those for downstream sites on the same streams. Faunal similarity between pairs of sites was typically higher for comparisons involving downstream sites than for those involving upstream sites. Loglinear analyses revealed significant heterogeneity among streams in overall abundances of fishes and distributions of individual species between upstream versus downstream localities. Although our data do not afford insight regarding temporal variation in SPNWR stream fish communities, we suggest that the substantial spatial heterogeneity revealed in this study may be of considerable importance in determining habitat suitability and nesting success for piscivorous shorebirds including the endangered least tern