East Texas contains the highest diversity of mussels in the state. Of the 37 species in East Texas, six are listed by the state as threatened and three have been proposed for listing as threatened or endangered under the U.S. Endangered Species Act. Although diverse, mussel populations are declining and few studies exist that establish habitat relationships identifying determinants of mussel distributions in the upper Sabine River. I explored potential habitat preferences of three state listed species using an occupancy modeling approach, including the: Texas Pigtoe, Fusconaia askewi, Sandbank Pocketbook, Lampsilis satura, and Texas Heelsplitter, Potamilus amphicaenus. Thirty sites, along a 225km section of the upper Sabine River between US Highways 69 (Smith County) and 79 (Panola County) were surveyed with 0.25m2 quadrats to estimate the occupancy of target species. F. askewi was the most abundant species, accounting for 92.3% of the collected mussels. Detection estimates based on sampling a 0.25m2 quadrat ranged among species from 0.11 to 0.71. I found no significant relationship between occupancy estimates and reach-level occupancy covariates, suggesting that mussels associate with larger scale habitat variables or other river processes. To further investigate the potential for habitat selection, non-metric multidimensional scaling was used to plot habitat data in a multidimensional space. An ANOSIM was performed to test for significant relationships between the habitat data and species presence. Although this study was not successful for elucidating habitat preferences, it provided insight into the level of effort required to detect target species.
Date of publication
Srini Kambhampati, Neil Ford, Amanda Rosenberger, Lance Williams
Masters of Science in Biology
Dickson, Jared, "HABITAT ASSOCIATIONS AND DETECTABILITY OF THREE UNIONID SPECIES ALONG THE UPPER SABINE RIVER IN EAST TEXAS" (2018). Biology Theses. Paper 54.