Distribution and abundance of fishes in tidal freshwater wetlands of the Cooper River, SC

M. G. McManus, L. Rose, and J. Bulak
South Carolina Department of Natural Resources, Freshwater Fisheries Research Project, Eastover, SC 29044; 803-353-8232; 803-353-8552 (fax). mcmanusm@scdnr.state.sc.us

We are testing if the distribution and abundance of fishes differs among 3 different forms of aquatic macrophytes in abandoned ricefields. Water flow in the Cooper River was reduced in 1985 and concomitantly the cover of wetland emergent vegetation, both intertidal and subtidal, has increased whereas subtidal submergent cover has decreased. Based on preliminary data of fish abundance, we are using a stratified sampling design for the collection of small fishes among the 3 macrophyte forms in 2 wetlands. We collect fish using an aluminum drop trap (100 x 100 x 100 cm). During spring sampling, the average number of fish collected per square meter was 35.0 for subtidal emergents, 20.5 for intertidal emergents, and 16.3 for subtidal submergents. Summer samples exhibit a similar pattern. Numerically dominant members of the fish assemblage include species of the Poeciliidae, Heterandria formosa and Gambusia holbrooki, and the Fundulidae, Lucania parva and L. goodei. This is similar to other studies of southeastern wetlands. Two species collected from these wetlands for the first time are Poecilia latipinna and Fundulus confluentus If we find an association between vegetative cover patterns and fish distribution and abundance, such information can be incorporated into basin level management plans.