5/25/2016  |   13:30 - 13:45   |  307

DOES OIL AND NATURAL GAS DEVELOPMENT AND HYDROLOGY INTERACT TO AFFECT FISH POPULATIONS? Managers and ecologists are under increased pressure to understand how stressors, natural or anthropogenic, interact to affect environmental change. Oil and natural gas (ONG) development has expanded at an unprecedented rate and our understanding of how stressors associated with these activities affect aquatic ecosystems is limited. Hydrology is also a strong regulator of stream ecosystems. Energy development and altered hydrology have been shown to individually affect streams; however less is known regarding how these stressors interact to affect ecological change. The objective of this study was to assess interactions between ONG development and hydrology on fish populations. Specifically, we examined changes in abundance of Mottled Sculpin (Cottus bairdii), Mountain Sucker (Catostomus platyrhynchus), and Colorado River Cutthroat Trout (Oncorhynchus clarki pleuriticus) across 60 sites in the Wyoming Range between 2012 and 2015. Preliminary results suggest fish abundances may shift through time in relation to interactions of ONG development and hydrology. By understanding interactions between anthropogenic and natural stressors we can better inform managers of best management practices needed to reduce negative effects in stream ecosystems.

Richard Walker (Primary Presenter/Author), University of Wyoming, rwalker2442@gmail.com;


Carlin Girard ( Co-Presenter/Co-Author), Teton Conservation District, carlingirard@gmail.com ;


Annika Walters ( Co-Presenter/Co-Author), University of Wyoming, awalter8@uwyo.edu;


Presentation:
This presentation has not yet been uploaded.

5/25/2016  |   13:45 - 14:00   |  307

EFFECTS OF MULTIPLE PRESSURES ON INVERTEBRATE ASSEMBLAGES OF BOREAL STREAMS Catchment land use often results in multiple stressors affecting the structure and function of aquatic ecosystems, and therefore understanding how stressors interact to affect the biology of aquatic ecosystems is a major challenge for freshwater management. Using a field survey approach, we studied single and multiple pressures effects of agricultural land use on invertebrate assemblages in 77 lowland, boreal streams. A substantial amount of variability in species and trait composition was shared between the main pressures, agriculture and alterations of hydrogeomorphology (HYMO). Consequently, unraveling the unique effects of these two pressures on community composition was not possible using variation partitioning. However, analysis of individual trait variables showed responses of feeding, habitat preference and resistance to disturbance that were in line with our predictions. Collectively, our results showed that unraveling pressure impacts and biological responses under high ecological realism of field studies is difficult and complicated by co-variance between pressures, but that species and trait composition show promise in the detection of different types of impairment.

Richard Johnson (Primary Presenter/Author), Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden, richard.johnson@slu.se;


Brendan McKie ( Co-Presenter/Co-Author), Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, brendan.mckie@slu.se;


David Angeler ( Co-Presenter/Co-Author), Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, david.angeler@slu.se;


Leonard Sandin ( Co-Presenter/Co-Author), Department of Aquatic resources, Swedish University of Agricultural Sciences , Leonard.Sandin@slu.se;


Simon Hallstan ( Co-Presenter/Co-Author), Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, simon.hallstan@slu.se;


Presentation:
This presentation has not yet been uploaded.

5/25/2016  |   14:00 - 14:15   |  307

WATER POLLUTION AND INFODISRUPTION: CHEMOSENSORY PERCEPTION OF FOOD AND PREDATORS BY RIVERINE INVERTEBRATES IS IMPAIRED BY A BRINE WASTEWATER EFFLUENT Many aquatic organisms rely on chemical cues to perceive information regarding predation risk, food availability, and other important ecological factors. Recent studies suggest that even low concentrations of some pollutants can disrupt the efficacy of chemical cues. Here we present experiments on the lethal and sublethal effects of a brine effluent derived from the natural gas industry and discharged into the Allegheny River. We focused on whether sublethal concentrations of brine water might impair predator avoidance or food finding ability of two common species of pulmonate gastropods. Conventional toxicity testing (LC50) revealed that brine concentrations in the range of 7-9% (approximately 5000 – 6000 mg/l TDS) were lethal to both species. Working in riverside mesocosms, we conducted a series of experiments manipulating both the concentration of brine water and olfactory cues associated with fish predation or food. These studies showed that sublethal concentrations of brine inhibited both predator avoidance and food finding ability, and that the concentrations necessary to reduce these behaviors to half of their baseline states were about ½ of the lethal concentrations.

Andrew Turner (Primary Presenter/Author), Clarion University, aturner@clarion.edu;


Brianna Reed ( Co-Presenter/Co-Author), Indiana University of Pennsylvania, reed16@gmail.com;


Presentation:
This presentation has not yet been uploaded.

5/25/2016  |   14:15 - 14:30   |  307

MERCURY CONTAMINATION AND THERMAL STRESS COMBINES TO HAVE DETRIMENTAL EFFECTS ON FRESHWATER MUSSEL-DRIVEN ECOSYSTEMS Modern freshwater ecosystems face an ever-growing array of threats and stressors. Among the most widespread are mercury (Hg) contamination, impoundment and flow alterations, and global climate change (GCC). Hg emitted from anthropogenic sources is converted into toxic methylmercury in aquatic ecosystems where it biomagnifies in the foodweb, threatening wildlife and humans, while impoundment, reduced in-stream flow, and GCC can contribute to increased thermal stress in many freshwater ecosystems. We conducted two experiments to test the combined effects of Hg and thermal stress modeled after the mussel-driven ecosystems of southeastern Oklahoma. We conducted a laboratory experiment examining the effects of Hg and thermal stress alone and in combination. We found decreased respiration and clearance rates in some mussel species, and high mortality in a thermally sensitive species when exposed to both stressors. We then performed a mesocosm experiment examining the effects of both stressors on invertebrate communities with and without mussels. Increased mussel mortality was observed again in double stressor treatments for multiple species. Analyses of ecosystem function (i.e. nutrient cycling and primary and secondary productivity) are underway.

Brent Tweedy (Primary Presenter/Author), University of Oklahoma, brent.tweedy@ou.edu;


Caryn C. Vaughn ( Co-Presenter/Co-Author), University of Oklahoma, cvaughn@ou.edu;


Presentation:
This presentation has not yet been uploaded.

5/25/2016  |   14:30 - 14:45   |  307

MULTI-CAUSAL INTERACTIONS OF ECOLOGICAL DRIVERS IN FLORIDA SPRING-FED RIVERS An ecological shift has been documented in several Florida spring ecosystems, where highly productive macrophyte-dominated communities have declined and nuisance algal communities have proliferated. Due to the broad-scale shifts that have occurred in aquatic autotroph composition and abundance that has led to the proliferation of nuisance algae (i.e. benthic macroalgae, epiphytic algae), greater attention has been drawn to the changing condition of spring-fed rivers. These shifts in primary producer community structure are attributed to multi-causal interactions of drivers that include water flow and velocity, nutrient loading, light availability, aquatic macroinvertebrate community distribution and other factors. We developed and analyzed a baseline of biological, physicochemical and hydrological condition in 14 spring ecosystems (26 transects) with the overall objective of gaining a better understanding of the multi-causal interactions of natural and anthropogenic drivers leading to changes in ecological health and stability of Florida springs and spring-fed rivers. This synoptic biological monitoring project covered a broad range of spring system types across North and Central Florida to capture the variability of physicochemical parameters, macrophytes, benthic macroalgae, epiphytic algae, and macroinvertebrate communities.

Mary Szafraniec (Primary Presenter/Author), Amec Foster Wheeler Environment & Infrastructure, mary.szafraniec@amecfw.com;


Margaret Guyette ( Co-Presenter/Co-Author), St. Johns River Water Management District, mguyette@sjrwmd.com;


Robert Mattson ( Co-Presenter/Co-Author), St. Johns River Water Management District, RMattson@sjrwmd.com;


Presentation:
This presentation has not yet been uploaded.

5/25/2016  |   14:45 - 15:00   |  307

CUMULATIVE IMPACTS OF NUTRIENT ENRICHMENT, SEDIMENTATION, AND NEONICOTINOID INSECTICIDES ON FRESHWATER ECOSYSTEM FUNCTIONING Even though agriculture is a primary agent of freshwater ecosystem degradation, information to disentangle the impacts of some of its ecological stressors is lacking. For example, neonicotinoids rank among the most purchased insecticides, but to date there are few studies documenting whether their combination with other agricultural stressors has synergistic or antagonistic impacts on freshwater ecosystems. We conducted a 36-day experiment in 32 outdoor freshwater mesocosms, manipulating fine sediment, nutrients, and a neonicotinoid insecticide (imidacloprid) to evaluate their individual and combined impacts on ecosystem function (net ecosystem production, phytoplankton biomass, periphyton biomass, leaf decomposition). In agreement with our expectations, the three individual stressors significantly altered net ecosystem production; nutrients and insecticide had positive effects, while sedimentation had negative effects. However, there was no evidence of complex interactions among the stressors for this metric. Nutrient enrichment was the only stressor with significant effects on phytoplankton biomass, whereas none of the stressors affected periphyton or decomposition. Our results evidence neonicotinoids have the potential to alter freshwater ecosystem function and highlight the importance of mesocosm experiments to isolate stressor effects in complex systems.

Ana Chara-Serna (Primary Presenter/Author), Department of Forest and Conservation Sciences, University of British Columbia, ana.chara@forestry.ubc.ca;


Luis B. Epele ( Co-Presenter/Co-Author), CIEMEP (CONICET-UNPSJB), luisbepele@comahue-conicet.gob.ar;


John Richardson ( Co-Presenter/Co-Author), Department of Forest and Conservation Sciences, University of British Columbia, john.richardson@ubc.ca;


Presentation:
This presentation has not yet been uploaded.