5/25/2016  |   15:30 - 15:45   |  315

QUAGGA AND ZEBRA MUSSEL MONITORING IN THE PACIFIC NORTHWEST, USA: HOW MUCH EFFORT IS NEEDED TO DETECT RARE PLANKTONIC TAXA IN THE COLUMBIA AND SNAKE RIVERS Recent studies suggest that the ecological and economic costs of an infestation of quagga and zebra (dreissenid) mussels in the Pacific Northwest, USA would be significant. We use information collected from 2012-2014 to characterize the spatial extent of dreissenid mussel veliger monitoring in the Pacific Northwest and place the efforts in the context of introduction and establishment risk. We also estimate the effort needed for high probability detection of rare planktonic taxa in the Columbia and Snake Rivers and whether current efforts provide for early detection of dreissenid mussels. We found that the effort to monitor for dreissenid mussels increased from 2012-2014, that regional efforts were distributed across risk categories ranging from high to very low, and that there are substantial gaps in our knowledge of introduction and establishment risk. The estimated effort required to fully census planktonic taxa, or to provide high detection of rare planktonic taxa, was high. The current level of effort expended does not provide for high probability detection of dreissenid mussel veligers or other planktonic taxa when they are rare in the reservoirs evaluated.

Tim Counihan (Primary Presenter/Author), USGS, Western Fisheries Research Center, Columbia River Research Laboratory; 5501 Cook-Underwood Road, Cook, WA 98605, tcounihan@usgs.gov;


Stephen M. Bollens ( Co-Presenter/Co-Author), Washington State University, sbollens@wsu.edu ;


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5/25/2016  |   15:45 - 16:00   |  315

CYANOBACTERIA REDUCES QUAGGA MUSSEL (DREISSENA ROSTRIFORMIS BUGENSIS) SPERM MOVEMENT Interactions between dreissenid mussels and phytoplankton are largely unknown and likely complex. Moreover, increased frequencies of cyanobacteria blooms in the Great Lakes since the invasion of dreissenid mussels may influence mussel reproduction. The objective of this study was to evaluate the effects of cyanobacteria exposure on quagga mussel (Dreissena rostriformis bugensis) fertility though an evaluation of sperm motility. Sperm was collected from individual mussels that were induced to spawn with serotonin and subsequently exposed to treatments of Microcystis aeruginosa, Aphanizomenon flos-aquae, water (control) and green algae (control). Mean distance traveled, mean acceleration, and mean velocity were calculated for up to 10 individual sperm per mussel (n=5). Aphanizomenon flos-aquae reduced overall sperm motility; both distance travelled and velocity were reduced by 62% (p<0.001), while acceleration was unaffected. Results with Microcystis aeruginosa were inconsistent. One population of M. aeruginosa reduced sperm mobility (p<0.001), although another did not (p>0.050). Our findings indicate that cyanobacteria can impact dreissenid reproduction, specifically sperm function. These findings suggest that cues emitted by A. flos-aquae may warrant investigation as potential tools for disrupting reproduction in invasive dreissenid mussels.

Karim Alame (Primary Presenter/Author), Wayne State University, ea4852@wayne.edu;


Anna Boegehold ( Co-Presenter/Co-Author), Wayne State University, az1079@wayne.edu;


Nicholas Johnson ( Co-Presenter/Co-Author), USGS Great Lakes Science Center, njohnson@usgs.gov;


Donna Kashian ( Co-Presenter/Co-Author), Wayne State University, dkashian@wayne.edu;


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5/25/2016  |   16:00 - 16:15   |  315

PREDICTING THE PRESENCE OF AN INVASIVE TOXIGENIC ALGAL SPECIES ON A REGIONAL SCALE As invasive species distributions expand in our changing world, one of the greatest challenges is the accurate prediction of at-risk areas. This challenge is particularly acute for invasive microbes, where distribution data are shaped by methodology-dependent detection limits. Of current concern is the toxigenic haptophyte, Prymnesium parvum, which causes ecosystem disruptive algal blooms. We set out to test the viability of applying a local random forest model based on six years of data from a subtropical reservoir to a regional scale. We predicted Prymnesium presence using parameters known to affect its growth and toxicity in lab experiments, and applied this model to data collected from four watersheds across Oklahoma and Texas. Error rates, which were lowest at intermediate detection limits, indicated that the same environmental factors influence Prymnesium presence on both local and regional scales. Of notable significance, higher error rates at low detection limits suggest that lower abundances are regulated more by dispersal than by environmental conditions, as presence does not necessarily equate to active growth and community participation in environments beyond the fundamental niche.

Jessica Beyer (Primary Presenter/Author), University of Oklahoma, beyer@ou.edu;


Richard M. Zamor ( Co-Presenter/Co-Author), Grand River Dam Authority, richard.zamor@grda.com;


K. David Hambright ( Co-Presenter/Co-Author), University of Oklahoma, dhambright@ou.edu;


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5/25/2016  |   16:15 - 16:30   |  315

WHOLE FOOD WEB RESTRUCTURING BY AN ECOSYSTEM DISRUPTIVE ALGAL BLOOM SPECIES Ecosystem disruptive algal blooms (EDABs) were first described as blooms of toxic or unpalatable algal species that disrupted energy flow and nutrient recycling by reducing grazing rates of planktonic and benthic herbivores. Inland water blooms of the toxigenic marine haptophyte, Prymnesium parvum, have been categorized as EDABs primarily because they can cause massive fish kills during blooms, although secondarily, some research has noted other effects, particularly on zooplankton feeding and survival. Here we present results of a long-term field and laboratory research program in which we have documented major shifts in pelagic communities during P. parvum blooms including dramatic restructuring of bacterial, protistan, zooplankton, and fish assemblages. Additionally, anecdotal evidence indicates changes in the dynamics of predation and fishing habits by bird and human populations, respectively. Thus P. parvum redefines and expands the concept of an EDAB to truly include the entire ecosystem. Although evidence is limited at present, we suspect that such major changes in community composition and dynamics across the entire food web will have profound ecosystem functional repercussions as well.

K. David Hambright (Primary Presenter/Author), University of Oklahoma, dhambright@ou.edu;


David A. Caron ( Co-Presenter/Co-Author), University of Southern California, dcaron@usc.edu;


Adriane C. Jones ( Co-Presenter/Co-Author), Mount Saint Mary's University, ajones@msmu.edu;


Brenda Allison Witt ( Co-Presenter/Co-Author), brenda.witt@redlandscc.edu, Redlands Community College;


Richard M. Zamor ( Co-Presenter/Co-Author), Grand River Dam Authority, richard.zamor@grda.com;


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5/25/2016  |   16:30 - 16:45   |  315

A TERRESTRIAL INVADER, EMERALD ASH BORER (AGRILUS PLANIPENNIS), INFLUENCES STREAM COMMUNITY SPECIES SORTING The terrestrial invasive insect, emerald ash borer (EAB), Agrilus planipennis, has killed millions of ash trees since it was first identified in North America in 2002, yet information about the impact of ash mortality on aquatic ecosystems is scarce. Mortality of ash trees along stream corridors can result in canopy gaps, which potentially affect primary production and food webs through aquatic invertebrate and microbial communities. We hypothesized that the stream metacommunity would undergo a functional shift, with differential coupled aquatic macroinvertebrate and microbial community response occurring directly below and downstream from canopy gaps. Initially we identified riparian plant communities and canopy gaps associated with dead ash trees, then sampled leaf litter, aquatic macroinvertebrate and microbial communities before, during and after autumnal leaf senescence. Results show that EAB-related ash mortality facilitates shifts in riparian plant communities, including a significant increase in the invasive Japanese barberry (Berberis thunbergii). Microhabitat conditions were also altered with significantly lower root wad presence beneath canopy gaps. These changes resulted in shifts of stream biofilm communities, which in turn influenced insect gut microbiomes and life history traits.

Courtney Larson (Primary Presenter/Author), U.S. Environmental Protection Agency, larson.courtney@epa.gov;
U.S. EPA

Jennifer L. Pechal ( Co-Presenter/Co-Author), Michigan State University, pechalje@msu.edu;


Deborah McCullough ( Co-Presenter/Co-Author), Michigan State University, mccullo6@msu.edu;


M. Eric Benbow ( Co-Presenter/Co-Author), Michigan State University, benbow@msu.edu;


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