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Ann Arbor, NC, United States

Witt M.J.,University of Exeter | Hawkes L.A.,Bangor University | Godfrey M.H.,North Carolina Wildlife Resources Commission | Godley B.J.,University of Exeter | Broderick A.C.,University of Exeter
Journal of Experimental Biology | Year: 2010

Marine turtles utilise terrestrial and marine habitats and several aspects of their life history are tied to environmental features that are altering due to rapid climate change. We overview the likely impacts of climate change on the biology of these species, which are likely centred upon the thermal ecology of this taxonomie group. Then, focusing in detail on three decades of research on the loggerhead turtle (Caretta caretta L.), we describe how much progress has been made to date and how future experimental and ecological focus should be directed. Key questions include: what are the current hatchling sex ratios from which to measure future climate-induced changes? What are wild adult sex ratios and how many males are necessary to maintain a fertile and productive population? How will climate change affect turtles in terms of their distribution? © 2010, Published by The Company of Biologists Ltd. Source

We surveyed U.S. state and Canadian provincial fish and wildlife agencies regarding their participation and approach to environmental review (i.e., review of project permit applications or proposals for environmental impacts). Most agencies dedicated a personnel unit to environmental review ranging from 1 individual to a staff of 38, and staffs are administered within various divisions or programs. Agencies annually reviewed from 10 to 7,500 projects for environmental impact, and state and provincial agencies spent an average of 3,681 hours (state) and 700 hours (provincial) on projects monthly. An average of 1,760 hours (state) and 390 hours (provincial) was spent annually on proactive measures such as environmental education and land use planning. Most agencies viewed environmental review as very important; however, agencies generally reported limited success in influencing the outcome of reviewed projects, and many identified this as a dissatisfying aspect of the review process. State and provincial agencies have adopted a variety of approaches to accomplish environmental review. Examining the alternative strategies and approaches employed among agencies may add perspective and provide successful models to enhance other agencies' programs. Source

Spear S.F.,The Orianne Society | Spear S.F.,University of Idaho | Groves J.D.,North Carolina Zoological Park | Williams L.A.,North Carolina Wildlife Resources Commission | Waits L.P.,University of Idaho
Biological Conservation | Year: 2015

Isolation of environmental DNA (eDNA) is becoming a valuable tool for detecting presence of rare or secretive aquatic species. The recent use of quantitative PCR (qPCR) with eDNA sampling presents the possibility of using this method to infer population abundance and status. This approach would be especially useful for species such as the Eastern hellbender (Cryptobranchus alleganiensis alleganiensis), a declining, secretive, aquatic salamander that requires intense field survey effort to study. In 2012, we conducted eDNA sampling at sites across the range of the species in North Carolina. Our objectives were to assess presence across 61 sites, test for a correlation of abundance and biomass with eDNA estimates at a subset of 23 sites, and sample at multiple spatial and temporal scales in three river systems. Overall, we detected hellbender eDNA at 33 sites, including all sites with 2012 hellbender records, 71% of all recent or historic sites with hellbender presence, and at nine sites that lack species occurrence records. We did not find a correlation between eDNA estimates and field survey counts of individuals or biomass. We detected a strong temporal increase in eDNA during the September breeding period, but no consistent evidence of a spatial relationship with eDNA. Overall, our results demonstrate the efficacy of eDNA for detecting hellbender populations. Furthermore, the potential utility of qPCR to assess population status in hellbenders requires further study and testing, although it may be promising for determining population reproductive status. © 2014 Elsevier Ltd. Source

Fisk J.M.,North Carolina State University | Kwak T.J.,U.S. Geological Survey | Heise R.J.,North Carolina Wildlife Resources Commission | Sessions F.W.,South Carolina Department of Natural Resources
River Research and Applications | Year: 2013

Riverine habitats have been altered and fragmented from hydroelectric dams and change spatially and temporally with hydropower flow releases. Hydropeaking flow regimes for electrical power production inundate areas that create temporary suitable habitat for fish that may be rapidly drained. Robust redhorse Moxostoma robustum, an imperiled, rare fish species, uses such temporary habitats to spawn, but when power generation ceases, these areas are dewatered until the next pulse of water is released. We experimentally simulated the effects of dewatering periods on the survival of robust redhorse eggs and larvae in the laboratory. Robust redhorse eggs were placed in gravel in eyeing-hatching jars (three jars per treatment) and subjected to one of four dewatering periods (6, 12, 24 and 48h), followed by 12h of inundation for each treatment, and a control treatment was never dewatered. Egg desiccation was observed in some eggs in the 24- and 48-h treatments after one dewatering period. For all treatments except the control, the subsequent dewatering period after eggs hatched was lethal. Larval emergence for the control treatment was observed on day 5 post-hatching and continued until the end of the experiment (day 21). Larval survival was significantly different between the control and all dewatering treatments for individuals in the gravel. These findings support the need for hydropower facilities to set minimum flows to maintain inundation of spawning areas for robust redhorse and other species to reduce dewatering mortality. © 2012 John Wiley & Sons, Ltd. Source

Bringolf R.B.,University of Georgia | Heltsley R.M.,Hollings Marine Laboratory | Newton T.J.,Upper Midwest Environmental science Center | Eads C.B.,North Carolina State University | And 3 more authors.
Environmental Toxicology and Chemistry | Year: 2010

The present study measured the occurrence, distribution, and bioaccumulation of fluoxetine in samples of water, polar organic chemical integrative sampler (POCIS), sediment, and caged freshwater mussels at stream sites near a municipal wastewater treatment facility effluent discharge. We assessed the relation of the environmental concentrations to reproductive endpoints in mussels in acute laboratory tests. Concentrations of fluoxetine in water and POCIS samples were similar (<20% difference) within each site and were greatest in the effluent channel (104-119 ng/L), and decreased at 50m and 100m downstream. Likewise, concentrations of fluoxetine in sediment and mussel (Elliptio complanata) tissue were greatest in the effluent channel (17.4 ng/g wet wt for sediment and 79.1 ng/g wet wt for mussels). In 96-h lab tests, fluoxetine significantly induced parturition of nonviable larvae from female E. complanata exposed to 300 μg/L ( p=0.0118) and 3,000 μg/L ( p<0.0001) compared to controls. Fluoxetine exposure at 300 μg/L ( p=0.0075) and 3,000 μg/L ( p=0.0001) also resulted in stimulation of lure display behavior in female Lampsilis fasciola and Lampsilis cardium, respectively. In male E. complanata, 3,000 μg fluoxetine/L significantly induced release of spermatozeugmata during a 48-h exposure. These results suggest that fluoxetine accumulates in mussel tissue and has the potential to disrupt several aspects of reproduction in freshwater mussels, a faunal group recognized as one of the most imperiled in the world. Despite the disparity between measured environmental concentrations of fluoxetine and effects concentrations in our short-term tests with these long-lived animals, additional tests are warranted to evaluate the effects of long-term exposure to environmentally relevant concentrations and critical lifestages (e.g., juveniles). Environ. Toxicol. Chem. 2010;29:1311-1318. © 2010 SETAC. Source

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