Oral Presentations Do river-reservoir interfaces serve as surrogate nurseries for floodplain-dependent riverine fishes? Matthew R. Acre*1,2, Timothy B. Grabowski2,3 , Nathan G. Smith4 1Department of Natural Resources Management, Texas Tech University 2Texas Cooperative Fish and Wildlife Resource Unit, Texas Tech University 3U.S. Geological Survey 4Texas Parks and Wildlife, Inland Fisheries Division Keywords: river-reservoir interface, larval fishes, assemblages Anthropogenic modification to riverine systems has reduced access to important off-channel nursery habitats. Some species utilize these floodplain habitats during early life history. The river-reservoir interface (RRI), a transitional zone between lentic and lotic habitats, may provide surrogate nursery habitats for these species. We sampled ichthyoplankton assemblages in riverine and RRI off-channel and main channel habitats in the Trinity River system of east Texas to compare species composition and abundance in these different habitat types and evaluate the influence of abiotic and physicochemical characteristics on ichthyoplankton assemblages. Ichthyoplankton was sampled using light traps and paired push nets deployed off jet-powered kayaks during February-July 2013 and 2014. Over 30,000 larval fishes were collected, representing 11 taxa. A few taxa were dominant at all sites, however, less common ichthyofauna such as moronids, centrarchids, and Freshwater Drum were captured more frequently in RRI habitats. In general, larval fish abundance, species richness, and species diversity, were greater in the RRI off-channel habitats than other habitat types. The duration and size of connection to the main channel best explained species richness, diversity, and overall abundance in RRI off-channel habitats. Our results suggest RRI habitat may serve as a surrogate nursery for some species. Genetic Structure of Striped Bass in the Southeastern United States and Effects from Stock Enhancement Andrew Anderson*1, Michael R. Denson2, Tanya L. Darden2 1Department of Biology, Texas A&M University 2South Carolina Department of Natural Resources Keywords: population genetics, fisheries management, stock enhancement It is necessary to understand the genetic relationships of Striped Bass Morone saxatilis populations within and between watersheds to identify appropriate management units. Determining temporal changes in genetic relationships as well as the genetic diversity of the populations is important in understanding how stock enhancement may have and continues to influence populations units. A suite of 12 microsatellites was used to evaluate patterns of Striped Bass gene flow both spatially and temporally across watersheds in the southeastern United States. Populations from the study watersheds were genetically diverse with the exception of the Savannah River which is recovering from a major population decline. Striped Bass in the Roanoke and Cape Fear rivers, North Carolina, represented a single population, most likely due to historical transfer stocking across the state from Roanoke River stock. Watersheds in South Carolina contained genetically distinct Striped Bass populations, although the difference between Striped Bass populations in the Ashepoo-Combahee-Edisto (ACE) and Santee- Cooper watershed has decreased over the past 15 years, likely due to the stocking of Santee-Cooper fish into the ACE Basin. Conversely, supportive breeding of the Santee-Cooper system has helped to maintain genetic diversity of the population. Striped Bass populations in the southeastern U.S. are good examples of the positive and negative effects of stock enhancement that must be considered and monitored when implementing or assessing a stock enhancement program. Occupancy, density, and dispersal of a critically endangered lizard on a small island Nicole Angeli*1, Ian Lundgren2, Clayton Pollock2, Zandy Hillis-Starr2, Lee A. Fitzgerald1,3 1Department of Wildlife and Fisheries Sciences, Texas A&M University 2Buck Island Reef National Monument, U.S. National Park Service 3Applied Biodiversity Sciences, Texas A&M University Keywords: Ameiva polops, translocations, monitoring, population estimation, occupancy, hierarchical Bayesian models Monitoring is a key component of animal translocation projects. The critically endangered St. Croix Ground Lizard (Ameiva polops) declined on mainland St. Croix due to mongoose and rat predation. To augment its populations, fifty-seven animals were translocated to Buck Island, St. Croix in 2008. With the goal of estimating the current size and extent of the population, we made visual counts of unmarked animals by multiple observers at an array of sites throughout Buck Island. The 61 observation sites covered 12% of the island, and were surveyed 3 times between March and May 2013. We used count data and habitat variables to estimate island-wide occupancy and to draw correlations among habitat variables and abundance. By May 2013, A. polops occupied 59% of the entire island. Over five years, the population increased at least four-fold from 57 to 1473 (CI: 940- 1802). After accounting for detectability and distance from the release site, models showed lizard abundance was correlated with temperature and habitat structure. We suggest that future translocations of A. polops to other locations are feasible and would be a worthwhile conservation and restoration strategy for this species. Hawaiian shell game: surveying cryptic species with PCR (Undergraduate) Brenda Bennett*1, Jessica Williams*1, Sharon Furiness1, Christopher E. Bird1 1Department of Life Sciences, Texas A&M University, Corpus Christi Keywords: PCR, cryptic species, limpets, morphologic Positive identification of morphologically similar species can be difficult, even by trained experts. Larvae of many marine species are very similar, and in some cases, even the adults are difficult to decipher. We are interested in deciphering between two siblings, endemic limpet species in the Hawaiian Islands, Cellana exarata and C. sandwicensis. Typically, the adult limpets are identifiable to the species level, but on Mokupāpapa, they are phenotypically indistinguishable. Using all known Cellana COI haplotypes, we designed several custom PCR primers whose terminus aligns to a diagnostic SNP, indicative of species identity. We tested the specificity and sensitivity of several primers using 50 unique haplotypes per species, and identified the best primer set for each target species. Finally, 58 unidentified limpets were collected from Mokupāpapa in a stratified random design by shore level and subjected to the PCR test. All limpets but one were identified as C. exarata. Our results, combined with a complete population census, indicate that C. sandwicensis does not have an established population on Mokupāpapa. Rather, the island is being repeatedly colonized from the southeastern island of Mokumanamana. Mosquito movement in the urban environment: a stable isotope mark-capture study Emily Boothe*1, Gabriel Hamer1, Mark Johnsen2 1Department of Entomology, Texas A&M University 2Brazos County Health Department Keywords: mosquitoes, mark-capture, Culex quinquefasciatus, Aedes albopictus, stable isotopes To better control populations of mosquitoes and break the transmission cycle of vector-borne diseases, it is crucial to understand the dispersal of female mosquitoes. We performed a stable isotope mark- capture study, focusing primarily on Culex quinquefasciatus and Aedes albopictus, to facilitate mechanisms to measure mosquito dispersal. Stable isotope enrichment is a non-invasive approach to quantifying dispersal and marks individual mosquitoes for the duration of their adult life. Naturally breeding mosquitoes were marked by enriching their larval habitat with 13C-glucose or 15N-potassium nitrate at two different locations (~0.5km apart) in south College Station, Texas. Eighty CDC light, gravid, and BG Sentinel traps were set up each week within a two kilometer radius of each of the enriched larval habitats for capture of marked mosquitoes. In total 720 tra p nights were completed from July to August 2013. Although stable isotope results for enriched female mosquitoes is still pending, of the 568 pools tested, twelve were successfully marked with 13C and eleven were marked with 15N. This study provides a greater understanding of the dispersal of arthropod vectors capable of transmitting diseases in urban environments. It also demonstrates the ability to use stable isotope enrichment as a means to study the biology of mosquitoes. Getting in shape? A geometric morphometric study of body shape divergence within two sympatric fish species (Atherinopsidae and Goodeidae) Luke Bower*1, Kimberly L. Foster2, Kyle R. Piller2 1Department of Wildlife and Fisheries Sciences, Texas A&M University 2Department of Biological Sciences, Southeastern Louisiana University Keywords: geometric morphometrics, selection, phenotypic plasticity, fish An important area of interest in evolutionary biology is the relationship between phenotypes and heterogeneous environmental gradients. At the population level, morphological trait divergence is the product of genetic differentiation and/or phenotypic plasticity via natural selection. These plastic morphological traits in concordance with habitat differences can result in divergent character selection of adaptive phenotypes. Steady-unsteady swimming performance model predicts the impacts of natural selection on morphology and locomotion abilities for fishes inhabiting different flow gradients. In this