TROPHIC IMPACTS OF INVASIVE CRAYFISH IN ALABAMA WATERSHEDS HARBORING HIGH NATIVE CRAYFISH DIVERSITY
Invasive species are a global threat to biodiversity and ecosystem function. The invasion of non-native crayfish species poses particular problems considering the significant ecological roles played by crayfish in aquatic ecosystems. Crayfish are typically considered generalists, yet the trophic ecology of most species is unknown. Moreover, most crayfish invasion studies have focused on effects of a single invasive taxon on relatively depauperate communities. Alabama currently has four documented invasive crayfish species – Faxonius virilis, Faxonius palmeri palmeri, Faxonius juvenilis, and Procambarus clarkii – that can co-occur with up to 35 native crayfish taxa embedded in species-rich assemblages of other aquatic invertebrates and fishes. We plan to compare trophic positions of the four invasive crayfish species with the native crayfish assemblage in 12 watersheds in north and central Alabama, USA. Sample sites have been chosen based on invasive/native crayfish sympatry/allopatry. Trophic measurements will come from quantitative microscopic analysis of stomach gut contents and stable isotope analysis. Previous studies have shown that invasive crayfish significantly alter food webs, so our study will examine the potential for significant differences in trophic position when found in sympatry vs. allopatry with native crayfish taxa.
Emma Arneson (Primary Presenter/Author,Co-Presenter/Co-Author), University of Alabama, firstname.lastname@example.org;
Jonathan Benstead (Co-Presenter/Co-Author), University of Alabama, email@example.com;
Stuart McGregor (Co-Presenter/Co-Author), Geological Survey of Alabama, firstname.lastname@example.org ;