5/25/2016  |   10:30 - 10:45   |  311-312

OF TRAITS, TEXT-MINING, AND DNA: NOVEL TECHNIQUES TO RESOLVE FOOD WEB PROPERTIES IN RIVER DELTA HABITATS Visualizing food webs requires knowledge of taxa and their trophic habits. Sampling limitations and a lack of readily available prior knowledge make this challenging, but advances in genomics and computational analysis show promise. Using DNA to characterize the composition of communities can be effective because it is non-invasive, sensitive, and provides a standardized detection method. Meanwhile, text-mining provides a method for targeted data-mining, allowing trait data to be gathered for specific taxa across large databases. We used a scalable engine for semantic automatic discovery and integration to query online databases for knowledge on benthic macroinvertebrate traits (e.g., trophic links, body size). We generated heuristic food webs using taxon lists from matched DNA and morphology samples for two river deltas in the Mackenzie Basin, Canada. We asked three questions. (1) How do food webs based on DNA and morphologically-identified material differ structurally (i.e., food chain length, trophic position, and link strength)? (2) How does food web structure relate to phylogenetic relationships? (3) How does food web structure differ between two delta habitats?

Zacchaeus Compson (Primary Presenter/Author), University of North Texas, zacchaeus.compson@unt.edu;


Wendy Monk ( Co-Presenter/Co-Author), Environment and Climate Change Canada @ Canadian Rivers Institute, Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, NB, Canada, wmonk@unb.ca;


Colin Curry ( Co-Presenter/Co-Author), Environment Canada @ Canadian Rivers Institute, colin.curry@unb.ca;


Christoper Baker ( Co-Presenter/Co-Author), University of New Brunswick, bakerc@unb.ca;


Alexandre Riazanov ( Co-Presenter/Co-Author), University of New Brunswick, alexandre.riazanov@gmail.com;


Ahmad Bukhari ( Co-Presenter/Co-Author), • Department of Computer Science and Applied Statistics, University of New Brunswick , sbukhari@unb.ca;


Rob Beiko ( Co-Presenter/Co-Author), Faculty of Computer Science, Dalhousie University, beiko@cs.dal.ca;


Mehrdad Hajibabaei ( Co-Presenter/Co-Author), Centre for Biodiversity Genomics & Department of Integrative Biology, University of Guelph, ON, Canada, mhajibab@uoguelph.ca;


Michael Wright ( Co-Presenter/Co-Author), University of Guelph, mwrigh06@uoguelph.ca;


Donald Baird ( Co-Presenter/Co-Author), Environment and Climate Change Canada @ Canadian Rivers Institute, Department of Biology, University of New Brunswick, Fredericton, NB, Canada, djbaird@unb.ca;


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5/25/2016  |   10:45 - 11:00   |  311-312

FOOD WEB OF THE WABASH RIVER The Wabash River ecosystem is altered by multiple anthropogenic impacts including hydrologic alterations, invasive species, historic industrial pollution, and excess nutrients. The fish assemblages changed dominant taxa during the mid-1990s, with all of these impacts. We examined food webs of the Wabash River using compound specific amino acid isotope analyses, to suggest potential mechanisms for linkages among food web members.

Mark Pyron (Primary Presenter/Author), Ball State University, mpyron@bsu.edu;


Robert Shields ( Co-Presenter/Co-Author), Ball State University, rcshields@bsu.edu;


Mario Minder ( Co-Presenter/Co-Author), Ball State University, mmminder@bsu.edu;


Brent Murry ( Co-Presenter/Co-Author), US Fish and Wildlife Service, Brent_murry@fws.gov;


Jesse Becker ( Co-Presenter/Co-Author), Ball State University, jcbecker@bsu.edu;


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5/25/2016  |   11:00 - 11:15   |  311-312

THE IMPACT OF DIDYMOSPHENIA GEMINATA MATS VARIES ACROSS TROPHIC LEVELS IN SOUTHERN APPALACHIAN STREAMS Didymosphenia geminata is a diatom that has formed nuisance mats in Southern Appalachian (SA) streams since 2004. Because mats cause considerable physical changes to oligotrophic streams with limited basal resources, they are expected to impact benthic food web structure and function. We studied the relationships among water quality, D. geminata mats, and food web structure for two years to compare to trends seen in other regions, adding an assessment of consumer resources use (stable isotopes and lipid analysis) to investigate potential mechanisms of structural change. Regional sampling using eDNA and traditional techniques showed mats in SA streams occur in habitats similar to those in other US regions. Mats increased macroinvertebrate abundance, and shifted composition to more chironomids and oligocheates and fewer EPT in the spring, but not summer. Resource switching occurred as macroinvertebrates shifted from feeding on rock biofilms to macrophytes. Impacts on fish were limited, with long-term trout data showing no strong change in numbers or quality. Lower and mid-tier food web components in these low nutrient systems did change, but top trophic levels had a muted response.

Justin Murdock (Primary Presenter/Author), Tennessee Technological University, jnmurdock@tntech.edu;


Natalie Knorp ( Co-Presenter/Co-Author), Tennessee Tech University, neknorp42@students.tntech.edu;


Lucas Hix ( Co-Presenter/Co-Author), Tennessee Tech University, lahix42@students.tntech.edu;


Andrea Engle ( Co-Presenter/Co-Author), Tennessee Tech University, anengle42@students.tntech.edu;


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5/25/2016  |   11:15 - 11:30   |  311-312

HYDROLOGICAL ALTERATION MEDIATES TROPHIC CASCADE EFFECTS IN A MEDITERRANEAN STREAM Eutrophication and hydrological alteration are two of the main drivers of biodiversity loss in freshwater ecosystems. Effects of intermittency and eutrophication were investigated in a Mediterranean stream in: 1) an intermittent location, located downstream an irrigation weir where water is abstracted; and 2) a permanent one, located upstream. Surveys were undertaken during early spring, when environmental conditions were more similar between locations. Macroinvertebrate density was clearly higher in the intermittent location, indicating that macroinvertebrates not only recovered from intermittency, but also had a faster recolonization rate. Grazing effects were also significant: P-uptake rate was higher and the C:N ratio lower, despite algal biomass remarkably decreased. These differences suggest that fish populations (Barbus meridionalis), with lower density in the intermittent location, exerted a poor control on grazers. Loss of the apex consumer had also negative effects on the uptake of ammonium. Biotic interactions may play an important role in running waters, even under eutrophic conditions where macroinvertebrates -delaying massive algal growth, and fish -preventing the accumulation of non-living benthic biomass, may partially counterbalance the effects that eutrophication has on nutrient dynamics.

Francesc Rubio-Gracia (Primary Presenter/Author), University of Girona, cesc.rubio.gracia@gmail.com;


David Almeida ( Co-Presenter/Co-Author), University of Girona, david.almeida@udg.edu;


Berta Bonet ( Co-Presenter/Co-Author), University of Girona, berta.bonet@udg.edu;


Frederic Casals ( Co-Presenter/Co-Author), Universitat de Lleida, fcasals@prodan.udl.cat;


Carmen Espinosa ( Co-Presenter/Co-Author), University of Girona, u1917287@campus.udg.edu;


Alexander Flecker ( Co-Presenter/Co-Author), Cornell University, Ithaca, NY, USA, asf3@cornell.edu;


Emili Garcia-Berthou ( Co-Presenter/Co-Author), University of Girona, emili.garcia@udg.edu;


Eugènia Martí ( Co-Presenter/Co-Author), Integrated Freshwater Ecology Group, Center for Advanced Studies of Blanes (CEAB-CSIC), Blanes, Girona, Spain, eugenia@ceab.csic.es;


Baigal-Amar Tuulaikhuu ( Co-Presenter/Co-Author), University of Girona, tbaigalamar@yahoo.com;


Anna Vila ( Co-Presenter/Co-Author), University of Girona, anna.vila@udg.edu;


Lluis Zamora ( Co-Presenter/Co-Author), University of Girona, lluis.zamora@udg.edu;


Helena Guasch ( Co-Presenter/Co-Author), Center for Advanced Studies of Blanes (CEAB-CSIC), Spain, helena.guasch@ceab.csic.es;


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5/25/2016  |   11:30 - 11:45   |  311-312

FAMILY-LEVEL DIVERSITY OF AQUATIC MACROINVERTEBRATES IN WESTERN SOUTH DAKOTA AND IMPLICATIONS FOR CHANNEL CATFISH DIETS Aquatic macroinvertebrates are important prey resources to consumers in freshwater ecosystems. Channel catfish (Ictalurus punctatus) consume invertebrates, but little is known about their invertebrate prey selectivity. Macroinvertebrates and channel catfish were collected from 25 river sites in western South Dakota to assess prey selectivity. Diversity and abundance of macroinvertebrates and composition similarity to catfish diet were compared between three river basins and along a longitudinal gradient within each basin. No significant family-level diversity differences were observed within or between river basins. Twenty-seven families were found in the environment and 17 in catfish diets. Hydropsychidae (clingers) and Chironomidae (burrowers) were the most abundant families in both. Family-level similarity between the environment and diets ranged from 0-55% and averaged 33.3%, and generally decreased moving downstream, whereas the pattern of similarity in habit guild was variable. Low similarity between the diets and the environment suggests that catfish may forage selectively for aquatic macroinvertebrates. Future work will carry the analysis to the generic level and include analysis of prey size structure and invertebrate biomass in catfish diets.

Erin Peterson (Primary Presenter/Author), South Dakota State University, erin.peterson@sdstate.edu;


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5/25/2016  |   11:45 - 12:00   |  311-312

CONSEQUENCES OF CHANGES IN COMMUNITY STRUCTURE ACROSS ENVIRONMENTAL GRADIENTS REVEALED USING BODY MASS-ABUNDANCE RELATIONSHIPS Community structure and stability are important properties of ecosystems and both depend on the complex network of interactions between organisms. Despite their complexity, interaction networks have consistent and simplifying patterns related to organism body size which should aid understanding of community structure and stability. Analysis of body mass (M)-abundance (N) relationships collected across environmental gradients of stream flow disturbance and habitat size revealed changes in community structure. Specifically, as habitat size increased, predator size but not biomass increased which was reflected in changes to M-N slopes. In comparison, flow disturbance primarily affected organism abundance revealed by changes in the intercepts of the M-N relationships. An in-stream channel experiment designed to investigate the effect of such changes in predator size revealed that many small top predators, reflective of smaller habitats was likely a less stable community structure than fewer, larger top predators. Thus, M-N relationships were a particularly useful, easy-to-measure, tool for understanding influences on community structure.

Helen Warburton (Primary Presenter/Author), University of Canterbury, helen.warburton@pg.canterbury.ac.nz;


Pete McHugh ( Co-Presenter/Co-Author), Utah State University, peter.a.mchugh@gmail.com;


Phillip Jellyman ( Co-Presenter/Co-Author), NIWA, Phillip.Jellyman@niwa.co.nz;


Hamish Greig ( Co-Presenter/Co-Author), University of Maine, hamish.greig@maine.edu;


Angus McIntosh ( Co-Presenter/Co-Author), University of Canterbury, angus.mcintosh@canterbury.ac.nz;


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