Assessing crayfish species diversity in the Lower Ogeechee River Basin

REU Fellow: Luis Acevedo, University of Puerto Rico - Mayagüez

Mentor: Dr. Checo Colón-Gaud

Crayfish are important members of aquatic ecosystems due to their role as: decomposers, detritivores and predators. Species assemblages in the southeastern US are historically understudied, despite high levels of diversity and endemism. The Ogeechee River is a blackwater river in southeast Georgia, USA that flows unimpeded, making it one of the most natural river systems in the region. Using passive trapping and modern genetic methods, we aimed to better describe the crayfish community of the Lower Ogeechee River.  Additionally, we wanted to test the relatedness of crayfish species within the basin using phylogenetic comparisons. We found 9 species of crayfish during the study, including the endemic Ogeechee Crayfish (Procambarus petersi). Additionally, we recorded a range expansion of the Devil Crayfish (Lacunicambarus diogenes) into the Ogeechee River Basin. Previous records documented the species in the Flint, Chattahoochee, Ocmulgee, and Savannah rivers within Georgia. We determined that crayfish communities change along the length of the Ogeechee River and our genetic methods performed well in creating a strong phylogeny for our collected species that reflect their evolutionary history.