Wednesday, May 25, 2016
15:30 - 17:00

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15:30 - 15:45: / 302-303 PATTERNS AND PROCESSES RELATED TO AMPHIBIAN CHYTRID FUNGI DETECTION IN LENTIC SYSTEMS

5/25/2016  |   15:30 - 15:45   |  302-303

PATTERNS AND PROCESSES RELATED TO AMPHIBIAN CHYTRID FUNGI DETECTION IN LENTIC SYSTEMS Emerging infectious disease (EID) events have increased in recent decades worldwide. The proportion of contemporary EID events caused by fungal agents outweighs all other disease agents. One such pathogen is the chytrid fungus Batrachochytrium dendrobatidis (Bd), which is implicated in global amphibian declines. Batrachochytrium salamandrivorans (Bsal) is also an emerging threat to salamanders. We investigated the ecology of Bd in lentic systems using molecular techniques, sampling both amphibians and water from their breeding sites. To investigate potential biotic and abiotic predictors of Bd in amphibian habitats, we conducted an exploratory analysis using machine-learning methods (boosted regression trees) to generate new hypotheses regarding Bd occurrence in amphibian breeding habitats. Amphibian density, species richness, and Bd infected amphibians were not related to Bd detection in the aquatic environment, suggesting that Bd does not require an amphibian host to persist in wetlands. This strategy would allow Bd to occupy a diversity of habitats when amphibians are seasonally absent, and could offer an explanation for its widespread distribution and persistence in aquatic habitats. These methods may also be effective for Bsal surveillance.

Tara Chestnut (Primary Presenter/Author), Mount Rainier National Park, tarachestnut@gmail.com;


Deanna Olson ( Co-Presenter/Co-Author), US Forest Service PNW Research Station, dedeolson@fs.fed.gov;


Chauncey Anderson ( Co-Presenter/Co-Author), USGS Oregon Water Science Center, chauncey@usgs.gov;


Andrew Blaustein ( Co-Presenter/Co-Author), Oregon State University, Andrew.blaustein@oregonstate.edu;


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15:45 - 16:00: / 302-303 SCALE SHAPE VARIATION IN A SPECIOSE AND HIGHLY IMPERILED GROUP OF FISHES, THE DARTERS (PERCIDAE: ETHEOSTOMATINAE)

5/25/2016  |   15:45 - 16:00   |  302-303

SCALE SHAPE VARIATION IN A SPECIOSE AND HIGHLY IMPERILED GROUP OF FISHES, THE DARTERS (PERCIDAE: ETHEOSTOMATINAE) This study seeks to identify factors affecting one aspect of darter (Percidae: Etheostomatinae) phenotype, scale shape. In a pilot study, scale shape and meristic data were taken from 236 individuals, representing 80 species, all genera, 26 subgenera, and 29 darter clades. Variation in number of ctenii and radii was observed among genera, subgenera, and clades. Multivariate principle components analysis revealed scale shape variation among subgenera and clades of Percina, and species of Ammocrypta and Nothonotus. Clades and subgenera of Etheostoma showed overlap in scale shape due to high levels of variation within each group, suggesting that for this genus, scale shape may be best explained at finer taxonomic levels. Given the observed variation, future work will investigate the relative impact of environment, behavior, and phylogeny on darter scale shape. Because scales aid in reducing drag and facilitating movement, understanding what factors affect variation will enhance our overall understanding of the ecology and evolution of this group of fishes and will help identify those species that will be most sensitive to long-term, large scale and short-term, localized impacts to riverine systems.

Jessica Grady (Primary Presenter/Author), Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, jgrady1@my.apsu.edu;


Rebecca Blanton Johansen ( Co-Presenter/Co-Author), Austin Peay State University, Center of Excellence in Field Biology, Clarksville, TN, johansenr@apsu.edu;


Courtney Weyand ( Co-Presenter/Co-Author), Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, courtneyweyand@gmail.com;


Sarah Lundin-Schiller ( Co-Presenter/Co-Author), Department of Biology, Austin Peay State University, Clarksville, TN 37040, schillers@apsu.edu;


Eva Grebe ( Co-Presenter/Co-Author), Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, egrebe@my.apsu.edu;


Zachary Holtel ( Co-Presenter/Co-Author), Department of Biology, Austin Peay State University, Clarksville, TN 37040, zholtel@my.apsu.edu;


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16:00 - 16:15: / 302-303 BIOLOGY OF SANTA ANA SUCKER (CATOSTOMUS SANTAANAE) AND ARROYO CHUB (GILA ORCUTTII) IN THE SANTA ANA RIVER, AN EFFLUENT DOMINATED URBAN RIVER

5/25/2016  |   16:00 - 16:15   |  302-303

BIOLOGY OF SANTA ANA SUCKER (CATOSTOMUS SANTAANAE) AND ARROYO CHUB (GILA ORCUTTII) IN THE SANTA ANA RIVER, AN EFFLUENT DOMINATED URBAN RIVER Understanding how sensitive species utilize available habitat is critical to inform sound management decisions, especially in regard to habitat protection and restoration. In support of local agencies developing a Habitat Conservation Plan for the Santa Ana River watershed, we examined the distribution and microhabitat utilization of native fishes in an effluent dominated reach of the Santa Ana River near Riverside, CA, which is part of the designated critical habitat for the Santa Ana sucker. In September 2015, native fish were most abundant in the middle areas of the study reach, which were characterized by high flows and coarse substrate. Snorkeling observations in July and September 2015 showed that both species avoided depths <30 cm and were generally observed within 2 m of cover. Chubs used a broad range of available mean water column velocities but suckers tended to select higher velocities with many observations >70 cm/s. Chubs were substrate generalists but suckers avoided sand in favor of gravel and cobble. These data will be useful in designing habitat restoration projects and understanding the ecological outcomes of water management actions.

Larry Brown (Primary Presenter/Author), U.S. Geological Survey, lrbrown@usgs.gov;


Jason May ( Co-Presenter/Co-Author), U.S. Geological Survey, California Water Science Center, jasonmay@usgs.gov;


Heather Dyer ( Co-Presenter/Co-Author), San Bernardino Valley Municipal Water District, heatherd@sbvmwd.com;


Kerwin Russell ( Co-Presenter/Co-Author), Riverside-Corona Resource Conservation District, russell@rcrcd.org;


Kai Palenscar ( Co-Presenter/Co-Author), U.S. Fish and Wildlife Service, kai_palenscar@fws.gov;


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16:15 - 16:30: / 302-303 CONTRASTING EFFECTS OF FISH PREDATION ON BENTHIC VERSUS EMERGING INSECTS

5/25/2016  |   16:15 - 16:30   |  302-303

CONTRASTING EFFECTS OF FISH PREDATION ON BENTHIC VERSUS EMERGING INSECTS Evidence that fish reduce benthic community biomass in freshwater ecosystems is mixed, but evidence that they reduce insect emergence to the terrestrial ecosystem is strong. We hypothesized that fish have stronger effects on emerging insects than on benthic insects, but that the size of this difference depends on the foraging traits of the fish (benthic versus pelagic). To test this hypothesis, we compared the effects of fish on benthic and emerging insects using enclosures/exclosures in a backwater of the Missouri River. Preliminary results suggest that benthic-feeding fish (omnnivorous Smallmouth Buffalo) reduced benthic insect densities by ~50% and reduced adult emergence by ~25%. In contrast, pelagic Green Sunfish had a positive effect on benthic insect densities (~350% increase), but a negative effect on emerging insects (~40% decrease). These results suggest that fish can reduce emergence to the terrestrial ecosystem, even in the absence of effects on benthic insects.

Charles Nearman (Primary Presenter/Author), University of South Dakota, c_nearman32@hotmail.com;


Jerry Warmbold ( Co-Presenter/Co-Author), University of South Dakota, jwarmbold@gmail.com;


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16:30 - 16:45: / 302-303 THE ROLE OF BED SEDIMENT IN NEW ZEALAND FISH COMMUNITY COMPOSITION.

5/25/2016  |   16:30 - 16:45   |  302-303

THE ROLE OF BED SEDIMENT IN NEW ZEALAND FISH COMMUNITY COMPOSITION. Intensive and long term land-use changes have led to increased inputs and retention times for fine inorganic sediment in streams and rivers. In New Zealand, fine inorganic sediment (<2mm) covering more than 20% of the bed has been linked to negative changes in invertebrate communities. This is reflected in a decline in EPT (i.e., Ephemeroptera Plecoptera and Trichopteraera) taxa with communities becoming dominated by pollution tolerant (e.g., Potamopyrgus sp. snails) and burrowing species (e.g., Chironomids). We have conducted an extensive survey of 50 waterways covering the South Island of New Zealand, to establish if bed sediment effects freshwater fish diversity and community composition. Preliminary data indicates that fish species are affected differently by sediment cover and some exhibit possible sediment thresholds. Other factors such as type of sediment, and sediment depth are important measures of sediment impacts.

Nicola Glenjarman (Primary Presenter/Author), University of Canterbury , nglenjarman@gmail.com;


Jon Harding ( Co-Presenter/Co-Author), University of Canterbury, jon.harding@canterbury.ac.nz;


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