University of Mississippi eGrove Electronic Theses and Dissertations Graduate School 2019 Effects of Impoundments on the Community Assemblage and Gene Flow of Stream Crayfishes Zanethia Choice Barnett University of Mississippi Follow this and additional works at: https://egrove.olemiss.edu/etd Part of the Biology Commons Recommended Citation Barnett, Zanethia Choice, "Effects of Impoundments on the Community Assemblage and Gene Flow of Stream Crayfishes" (2019). Electronic Theses and Dissertations. 1548. https://egrove.olemiss.edu/etd/1548 This Dissertation is brought to you for free and open access by the Graduate School at eGrove. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of eGrove. For more information, please contact
[email protected]. EFFECTS OF IMPOUNDMENTS ON THE COMMUNITY ASSEMBLAGE AND GENE FLOW OF STREAM CRAYFISHES A Dissertation Presented in partial fulfillment of requirements for the degree of Doctor of Philosophy in the Department of Biological Sciences The University of Mississippi By ZANETHIA CHOICE BARNETT May 2019 ABSTRACT Dams and their impoundments block movement of stream organism and change stream physiochemical properties, which subsequently changes biological assemblages and creates barriers to gene flow. While changes in species assemblages and gene flow have been assessed for numerous impoundments and stream organisms, no study has assessed the effects of large impoundments on crayfish assemblages and population genetic diversity and connectivity. I examined the physiochemical, biological, and genetic effects of impoundments on crayfishes. Between May 2015 and August 2017, I sampled multiple sites up- and downstream of three impounded streams, and along the lengths of two unimpounded streams, in the Bear Creek and Cahaba River drainages in Alabama, USA.