Freshwater turtles are key indicators of habitat health and play a critical role in the food chain and seed dispersal. Red-eared sliders (Trachemys scripta elegans) are native to southern Ohio but have since expanded to central Ohio due to the pet trade. Expanding to nonnative areas, red-eared sliders may compete with native turtles for space and food. This study aims to describe the turtle community in Otterbein Lake, Westerville, Ohio, USA to examine species richness, diversity, and evenness and to analyze their diet composition. I caught turtles (n=61) with baited hoop nets and basking traps from July – Oct 2023. I then collected fecal samples by holding turtles individually in tubs of water for 36 hours. Six species were observed including red-eared sliders, northern map turtles (Graptemys geographica), midland painted turtles (Chrysemys picta marginata), eastern spiny softshells (Apalone spinifera spinifera), eastern musk turtles (Sternotherus odoratus), and common snapping turtles (Chelydra serpentina). I estimated that 113 turtles live in Otterbein Lake with 72 red-eared sliders based on the Schnabel method and extracted DNA from the fecal samples (n=46) using Qiagen DNeasy Plant Pro Kits. I analyzed the turtle diet composition based on amplicon presence via polymerase chain reaction of extracted DNA using six primers of known specificity to plastid, mitochondrial, and nuclear loci of insects, amphibians, fish, and Viridiplantae clades including angiosperms, gymnosperms. There was a significant difference between species and their diets. Eastern spiny softshell, midland painted, northern map, and red-eared slider diets collectively included angiosperms species, insects, and amphibians. Eastern spiny softshell turtles were the only species to exhibit fish in their diets. I did not detect gymnosperms in any diets within this study, suggesting that our primers were specific to diet rather than environmental DNA
