5/19/2015  |   13:30 - 13:45   |  102D

RELATIVE INFLUENCE OF ALTERED FLOW AND WATER TEMPERATURE ON STREAM HEALTH IN SIERRA NEVADA STREAMS, CALIFORNIA There is a need to understand specific streamflow characteristics that, when altered by humans, have the greatest effect on stream health. We designed a study to assess how flow and thermal alteration were associated with the condition of invertebrate communities in 30 Sierra Nevada streams that span a wide range of hydrologic modification. Daily water temperature and streamflows were continuously monitored, and basic chemistry and habitat conditions were characterized when invertebrate communities were sampled. Streamflow alteration, thermal alteration, and invertebrate condition were quantified by predicting site-specific natural expectations using statistical models developed at a large network of reference sites. Monthly flows were typically depleted during fall, winter, and spring. Thermal conditions of most hydrologically altered streams were colder than natural in summer but relatively natural during winter. The most influential predictor of invertebrate community condition was the degree of alteration of March flows, which suggests there are key interactions between hydrological and biological processes during this month. Thermal alteration was also an important factor—particularly at the more extreme hydrologically altered sites.

Daren Carlisle (Primary Presenter/Author), U.S. Geological Survey, dcarlisle@usgs.gov;


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


S. Mark Nelson (Co-Presenter/Co-Author), Bureau of Reclamation, snelson@usbr.gov;

5/19/2015  |   13:45 - 14:00   |  102D

BIOTIC RESPONSE TO FLOW ALTERATION IN MID-ATLANTIC STREAMS Hydrologic alteration is an important driver of stream impairment; however, it is difficult to study because hydrologic monitoring is not regularly performed with biomonitoring because of prohibitive costs. We avoided this issue by using a novel statistical method for modeling flow and applied the method to thousands of ungauged streams in Maryland that were sampled for invertebrates and fish. We ordinated the correlation between the daily flows of USGS gauged streams in the Mid-Atlantic in an NMDS and then fit GAM models to predict a stream’s position in ordination space. The models were used to identify the best predictor gauges for each ungauged stream in the Maryland Biological Stream Survey dataset which we used to estimate hydrologic metrics (flashiness, magnitude, minimum flow, etc) relevant to fish and macroinvertebrates. We evaluated the relationship between flow and metrics related to community composition including richness, diversity, functional diversity, and traits specifically related to flow metrics, such as desiccation resistance. We also compared the range of values obtained for flow metrics across the dataset to values observed in reference quality streams in the region.

Christopher Patrick (Primary Presenter/Author), Virginia Institute of Marine Science (VIMS), cpatrick@vims.edu;


Lester Yuan (Co-Presenter/Co-Author), U.S. Environmental Protection Agency, yuan.lester@epa.gov;

5/19/2015  |   14:00 - 14:15   |  102D

CHARACTERIZING THE IMPACTS OF ALTERNATIVE FLOW REGIMES ON MULTIPLE BIOLOGICAL INDICATOR COMMUNITIES: CONGRUENCE, CORRELATION AND MANAGEMENT STRATEGY Where two communities are concordant, there is potential for one to be used as a surrogate for the other. This is important for water quality assessments, understanding ecohydrological conditions, and predicting responses of communities to hydromorphological alterations. We assessed the concordance of stream biological communities across flow regimes (slope). Stream macroinvertebrate and diatom communities were compared across 3 management-defined river flow regime categories. Macroinvertebrate community composition varied among flow regimes. Sites of low flow had similar communities, sites of high flow had similar communities, but communities at sites of moderate flow were not distinctly different from those of low or high flow. Diatom community composition did not vary among the flow regimes defined in the current study. Macroinvertebrate and diatom communities were not significantly concordant, either within or between flow regime categories. These findings do not support the use of management strategies that use river flow regime as determined by slope, suggesting that finer scale measurement or habitat assessment may be required for each taxonomic grouping of interest.

Caroline Wynne (Primary Presenter/Author), Michigan State University, wynnecaroline1@gmail.com;


Niamh Sweeney (Co-Presenter/Co-Author), APEM Consultancy, ns1818@gmail.com;


Suzanne Linnane (Co-Presenter/Co-Author), Dundalk Institute of Technology, suzanne.linnane@dkit.ie;

5/19/2015  |   14:15 - 14:30   |  102D

INCORPORATING SPECIES TRAITS IN A GUILD APPROACH TO DEVELOP ENVIRONMENTAL FLOW RECOMMENDATIONS FOR FRESHWATER MUSSELS North American freshwater mussels (Unionidae) are imperiled and very sensitive to flow alterations. Previous attempts to develop environmental flows for mussels have struggled to accommodate their varied habitat requirements and complex life histories. We review what is known about the habitat requirements of mussels, how they can vary among species within a community, and how this variation influences the effectiveness of different environmental flow methodologies. We propose a trait based environmental flow method that addresses the needs of mussel guilds differentiated by their thermal tolerances and reproductive strategies. Used previously for fish, plants and macroinvertebrates, the guild approach groups species by traits and identifies flow requirements of guilds as opposed to entire communities. We apply the guild approach to the mussel fauna of the Kiamichi and Little Rivers in southeastern Oklahoma, U.S.A., and illustrate how changes in the hydrograph can be made to better meet the seasonal flow needs of differing mussel guilds and their host fish. The guild approach can be adapted among regions where trait data are available or combined with rating models that estimate trait data.

Kiza Gates (Primary Presenter/Author), Washington Department of Fish and Wildlife, kizagates@gmail.com;


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


Jason P. Julian (Co-Presenter/Co-Author), Texas State University, jason.julian@txstate.edu;

5/19/2015  |   14:30 - 14:45   |  102D

MACROINVERTEBRATES RESPONSES TO ANTECEDENT FLOWS: HYDRAULICS OR HYDROLOGY? Over the last 25 years, researchers have advocated that hydraulics should be more proximal to benthic distributions than gross measures of hydrology. Recent modelling advances allow ecologists to generate hydraulics over defined time periods prior to sampling events, thus overcoming a major criticism of many early studies, viz. that instantaneous hydraulic measures were unlikely to represent what the benthos had experienced in the weeks before sampling. We surveyed and sampled 12 sites in 6 Tasmanian rivers over 5 years with contrasting hydrologies. Habitat-specific hydraulic measures were computed from modelled flows at hourly time steps for each habitat within each site and summarised for seven different time-spans. Quantile regressions showed modest relationships between some hydraulic variables and two flow-related trait groups. Multivariate analyses in trait space found that hydrological variables explained > 3 × the variance of hydraulic variables, but total variance explained was still ca. 50%. So, while coarse hydrology might not be so bad, some stakeholders will be unconvinced by the strength of these relationships. We need to consider carefully the limitations of correlative data sets in these contexts.

Leon A. Barmuta (Primary Presenter/Author), University of Tasmania, Leon.Barmuta@utas.edu.au;


Scott A. Hardie (Co-Presenter/Co-Author), DPIPWE Tasmania, Scott.Hardie@dpipwe.tas.gov.au;


Chris Bobbi (Co-Presenter/Co-Author), DPIPWE Tasmania, Chris.Bobbi@dpipwe.tas.gov.au;


Danielle M. Warfe (Co-Presenter/Co-Author), University of Tasmania, Danielle.Warfe@utas.edu.au;

5/19/2015  |   14:45 - 15:00   |  102D

LINKAGES BETWEEN STREAM FLOW, HABITAT, AND BIOTIC ASSEMBLAGES IN AN URBANIZED LARGE RIVER With increased pressure from a growing human population, managers are challenged to understand how novel disturbances (e.g., climate change, increased water withdrawals, urbanization) may affect natural resources. The Sudbury River is a National Wild and Scenic River with myriad impairments (e.g., mainstem impoundments, withdrawals, and urbanization) that is under increasing pressure from hydrologic alteration. In summer 2014, we sampled fishes, mussels, and macroinvertebrates along the main stem, and surveyed channel cross sections and profiles. Analysis of stream gage data indicates a roughly 200% increase in rise rates, an approximate 65% decrease in 1-day minimum flows, and a trend towards increasing high flow pulse counts. The most abundant mussel species collected were the cosmopolitan Eastern elliptio (58%) and Eastern lampmussel (40%). The fish assemblage has shifted from one that should be dominated by fluvial specialist species to one overwhelmingly dominated by macrohabitat generalists (90.6%). Overall, the current fish community has a 22.7% similarity to the target (reference) fish community. This case study demonstrates how a traits-based approach can be used to assess biotic stressors and identify potential for future impairment.

Allison Roy (Primary Presenter/Author), U.S. Geological Survey, Massachusetts Cooperative Fish and Wildlife Research Unit, University of Massachusetts Amherst, aroy@eco.umass.edu;


Stephen Jane (Co-Presenter/Co-Author), Massachusetts Cooperative Fish and Wildlife Research Unit, University of Massachusetts, coachman7777@yahoo.com;


John Finn (Co-Presenter/Co-Author), University of Massachusetts, finn@eco.umass.edu;


Peter Hazelton (Co-Presenter/Co-Author), Warnell School of Forestry and Natural Resources, University of Georgia, peter.hazelton@state.ma.us;


Timothy Randhir (Co-Presenter/Co-Author), University of Massachusetts, randhir@eco.umass.edu;


Todd Richards (Co-Presenter/Co-Author), Massachusetts Division of Fisheries and Wildlife , todd.richards@state.ma.us;