Competitive Interactions Between Exotic and Imperiled Native Crayfishes

The Red Swamp Crayfish, Procambarus clarkii, is one of Earth’s most widely distributed, invasive freshwater animals. In North Carolina, the range of P. clarkii has increased dramatically across the ranges of two imperiled, endemic species: the Waccamaw crayfish (P. braswelli) and the Sandhills crayfish (P. pearsei). I studied the potential for competitive impacts of P. clarkii on these native species using behavioral trials, stable isotope analysis and a field experiment. My results suggest that encounter competition with P. clarkii could lead to reduced growth rates and facilitate the displacement of native crayfishes despite potential differences in diet.