AbstractsBiology & Animal Science

In order to effectively manage and conserve species, it is essential to have a basic understanding of their ecology. Unfortunately, such information is unavailable for most crayfish species, including the two members of the genus Barbicambarus. To obtain ecological data I conducted surveys for Barbicambarus simmonsi within the Shoal Creek drainage in Lawrence County, Tennessee and Lauderdale County, Alabama from Summer 2013-Spring 2014. The objectives of the first part of my study were to determine distribution, habitat use, and site occupancy of the Tennessee Bottlebrush Crayfish, Barbicambarus simmonsi. The distribution was increased from 3 to 14 sites across Shoal Creek. Habitat use modeling did not yield significant results, but observations indicate large flat boulders as utilized habitat. Flow was the most important covariate when determining site occupancy, but this should be interpreted with some caution, as it does not match field observations. The objectives of the second part of my study were to determine trophic position and diet of B. simmonsi and B. cornutus using stable isotope analysis and gut content analysis, and determine if there was correlation between carapace length and trophic position for each species. Crayfish for the analysis were collected during the fall of 2012 and the spring of 2013. My results indicate both species occupy a higher trophic position compared to other sympatric crayfish species. I also noted a significant positive correlation between trophic position and body size. My data suggest Barbicambarus species function as a predator within the stream and there is some niche separation between them and other crayfish species.