Abstracts Acre-Chafin
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Abstracts Acre-Chafin Last Edited 6/5/2017 0252 ASIH STOYE ECOLOGY & ETHOLOGY IV, Friday 14 July 2017 Matthew Acre1, Timothy Grabowksi2, Dakus Geeslin3, Allison Pease1, Nate Smith3 1Texas Tech University, Lubbock, TX, USA, 2Hawaii Cooperative Fishery Research Unit, Hilo, HI, USA, 3Texas Parks and Wildlife, Austin, TX, USA Movements and Demography of Cycleptus elongatus in the lower Colorado River, TX Alteration of flow regime, e.g., timing, duration, flashiness, and magnitude of discharge, has serious implications to fluvial specialists inhabiting large rivers that have evolved flow-dependent life histories. Blue Sucker Cycleptus elongatus, is one such species that is considered vulnerable throughout its range due to its habitat requirements and life- history traits. However, the relationships between stream discharge and habitat use and recruitment in C. elongatus have not been thoroughly examined, particularly in southern portions of its range. The primary objectives of this research were to assess effects of varied streamflow levels, regulated by water releases from upstream reservoirs, on C. elongatus movement, habitat use, and recruitment in the lower Colorado River downstream of Austin, Texas. Radio and acoustic telemetry was used to characterize movement in response to river discharge changes. Results suggest large-scale movements are related to season and flow regime prior to a relocation event. Furthermore, home range and minimum displacement are correlated with riffle density. Additionally, fin-ray sections (n = 105) taken from specimens during mark-recapture efforts were used to estimate age and associate relative year-class strength with historical flow regimes. Preliminary results suggest the population in the lower Colorado River has had limited recruitment, and stronger cohorts appear to be associated with years with higher discharge. This work will provide critical information regarding conservation and protection of C. elongatus in Texas and inform water management policy decisions affecting instream flows in the lower Colorado River. ______________________________________________________________________________ 0543 Reptile Behavior, Friday 14 July 2017 Connor Adams1, Timothy Garrett1, Toby Hibbitts1, Wade Ryberg1, Tyler Campbell2 1Texas A&M University, College Station, TX, USA, 2East Foundation, TX, USA Home Range and Movements of the Reticulate Collared Lizard (Crotaphytus reticulatus) in South Texas The Reticulate Collared Lizard, Crotaphytus reticulatus, is one of the largest species of lizards in Texas. It is restricted to the South Texas Plains Ecoregion, mainly along the western edge of the Rio Grande Valley, in which the western extent of the South Texas Sandsheet gives way to areas of gravelly soils and lime-stone caliche hills dominated by dense thornscrub. This species is uncommon within its Texas distribution, but populations are believed to be stable, as much of their known habitat occurs within large ranches. The ecology and natural history of C. reticulatus is poorly understood and detailed studies on home range size and movements have not been conducted. The recent development of the Eagle Ford Shale, in this region is a new potential threat, and the ways in which energy development will impact this species are unknown. We conducted a two-year telemetry study at two sites on the San Antonio Viejo Ranch in Jim Hogg and Starr counties of Texas. Preliminary results suggest males have larger home ranges than females; however, this was not significant (t=-1.6151, P=0.15). Here we add the results of a second year of telemetry research to more completely determine the home range size and movements of C. reticulatus in South Texas. ______________________________________________________________________________ 0251 Poster Session II, Rio Grande Exhibit Hall, Saturday 15 July 2017 Cory Adams, Daniel Saenz Southern Research Station, USDA Forest Service, Nacogdoches, TX, USA Effects of Chinese Tallow Catkins on a Spring Breeding Anuran Chinese tallow (Triadica sebifera) is an aggressive invasive species that has become a major component of the landscape in the southeastern United States. Recent studies have demonstrated that Chinese tallow leaf litter can cause mortality in amphibian larvae and eggs by causing drastic changes in water chemistry. The effects of the leaf litter on water chemistry are short lived and thus are primarily a threat to winter breeding species and species that overwinter as larvae. As a result, a large subset of species may escape any adverse effects of Chinese tallow leaf litter simply due to reproductive phenologies that keep eggs and larvae out of the water at a time when leaf litter is present. For this study, we examine the potential impacts of Chinese tallow catkins (elongate clusters of pollen producing flowers), as these structures tend to abscess and fall from trees in large quantities in late spring. We exposed Gulf Coast toad larvae (Incilius nebulifer) to various concentrations of Chinese tallow catkins and determined water chemistry and tadpole survival. Toad tadpole survival was very low and mortality occurred very quickly in our trials. We found that catkins had a more pronounced effect on deoxygenation of the water than the leaf litter. Our findings suggest that Chinese tallow catkins have the potential to threaten summer and spring breeding amphibians in much the same manner as leaf litter in the fall and winter. ______________________________________________________________________________ 0715 Poster Session II, Rio Grande Exhibit Hall, Saturday 15 July 2017 Michelle E. Adcock1, Zachary C. Adcock1, J. Steve Godley2 1Texas State University, Texas, USA, 2Cardno, Riverview, Florida, USA Tail loss in Sympatric Sirenid Salamanders from Rainey Slough, Florida Tail loss in sirenid salamanders may be caused by intraspecific aggression, interspecific aggression, or predatory interactions. We evaluated the frequency of tail loss in three sympatric species of sirenids (Siren intermedia, Siren lacertina, and Pseudobranchus axanthus) in a water hyacinth (Eichhornia crassipes) community at Rainey Slough, Glades County, Florida from 1974 through 1979. We determined if correlations exist between the frequency of sirenid tail loss and intra- and interspecific density of sirenids and the density of some potential predator species. Frequency of tail loss was 18% in 537 S. intermedia, 15% in 474 P. axanthus, and 4% in 100 S. lacertina. Both P. axanthus and S. lacertina tail loss was not significantly correlated with any of the measured variables. However, S. intermedia tail loss was significantly correlated with intraspecific density and the density of total predators. Our findings suggest that S. intermedia may be intraspecifically more aggressive than either S. lacertina or P. axanthus. ______________________________________________________________________________ 0716 Herp Reproduction & Life History I, Thursday 13 July 2017 Zachary C. Adcock, Michael R.J. Forstner Texas State University, Texas, USA Reproductive Ecology of Federally Threatened Jollyville Plateau Salamanders (Eurycea tonkawae) with Comments on Management Implications Jollyville Plateau Salamanders (Eurycea tonkawae) are small, neotenic salamanders that occupy aquifer and spring habitats in Travis and Williamson Counties, Texas. The U.S. Fish and Wildlife Service listed E. tonkawae as threatened in 2013, but basic life history data that are critical for informing management and conservation policies are limited for this taxon. We conducted monthly to bi-monthly E. tonkawae surveys at six sites in four federal critical habitat units from 2013 to 2016. We recorded total length (TL), snout-vent length (SVL), and microhabitat for each captured salamander and non-invasively inspected its body cavity for oocytes. We captured a total of 815 E. tonkawae, of which, 45 were gravid females. The minimum size of a gravid female was 23.6 mm SVL, and gravid females contained between 1 – 21 visible oocytes. The percentage of gravid females across all sites peaked from November to February, and the percentage of juveniles and subadults peaked approximately two to three months later. We found gravid females disproportionately abundant at some sites, suggesting differential reproductive effort. However, juvenile abundance was proportional among sites. We never observed eggs, strongly suggesting that oviposition occurs subsurface. Smaller size class salamanders may be avoiding adults, as chi-square goodness of fit tests revealed that juveniles and subadults selected different microhabitat structure types than adults. Future management and policy decisions should consider the potential importance of all types of microhabitat structure and subsurface habitat for the reproductive ecology of this taxon. ______________________________________________________________________________ 0015 Fish Morphology, Saturday 15 July 2017 Dominique Adriaens1, Jens De Meyer1, Mathias Bouilliart1, Joachim Christiaens1, Claude Belpaire2, Sam Van Wassenbergh3, Anthony Herrel3, Jonna Tomkiewicz4, Peter Lauesen4, Gregory Maes5, Ron Dirks6, Pascal Boeckx1, Lieven Bervoets7, Adrian Covaci7, Govindan Malarvannan7, Akihiro Okamura8, Jelle Dhaene1, Luc Van Hoorebeke1, Barbara De Kegel1 1Ghent University, Ghent, Belgium, 2Institute for Nature and Forest Research, Brussels, Belgium, 3CNRS, Paris, France, 4Denmark Technical University, Copenhagen, Denmark, 5Catholic University of Leuven, Leuven, Belgium, 6ZF Screens, Leiden, The Netherlands, 7Antwerp University,