Effects of the freshwater turtle Trachemys scripta elegans on ecosystem functioning: an approach in experimental ponds

The effect of red-eared sliders ( Trachemys scripta elegans ) on aquatic ecosystem processes and macroinvertebrate community was investigated in artificial ponds that were stocked with turtles or kept free of them. Compared to ponds without turtles, ponds with turtles displayed significantly higher values of pH, conductivity, sediment accumulation, and leaf litter decomposition rates, as well as a higher abundance of invertebrates, specifically that of the Hemiptera and Ephemeroptera. The biomass of periphyton was not affected by the presence of turtles. These results suggest that the presence of T. s. elegans affects environmental conditions in ponds, and thus potentially ecosystem processes. Reduced abundance or loss of turtles in aquatic systems could therefore result in significant consequences on ecosystem functioning.