Tuesday, May 19, 2015
10:30 - 12:00

<< Back to Schedule

10:30 - 10:45: / 102B QUANTIFYING ECOLOGICAL TRAITS TO PREDICT SPECIES, COMMUNITY AND ECOSYSTEM RESPONSES TO CHANGING ENVIRONMENTS

5/19/2015  |   10:30 - 10:45   |  102B

QUANTIFYING ECOLOGICAL TRAITS TO PREDICT SPECIES, COMMUNITY AND ECOSYSTEM RESPONSES TO CHANGING ENVIRONMENTS The interrelationships of the environment, biodiversity and ecosystem functioning, is an important ecological principle with special relevance to both estimating global change impacts and guiding aquatic management and conservation. Ecosystem functioning is closely related to the distribution of traits that organisms possess, which reflect ecological characteristics of species, communities, or ecosystems. These traits may be a general characteristic of species or drive ecological processes (effects traits), or they may reflect a preference or sensitivity to change related to varying environmental conditions (response traits). We will give recent examples of developments in quantifying ecological traits and the use to predict species, community and ecosystem responses to changing environments, e.g. new (empirical) methods to derive environmental preferences or sensitivities, the use of traits in ecological prediction frameworks and incorporating trait information into ecological management or conservation approaches.

Sonja C. Jähnig (Primary Presenter/Author), Leibniz-Institute of Freshwater Ecology and Inland Fisheries, sonja.jaehnig@igb-berlin.de;


LeRoy Poff (Co-Presenter/Co-Author), Colorado State University, n.poff@rams.colostate.edu;


10:45 - 11:00: / 102B RESPONSES OF RIVERINE MACROINVERTEBRATE COMMUNITIES TO ANTHROPOGENIC DISTURBANCE: IMPLICATIONS FOR BIOASSESSMENTS AND TRAITS-BASED MONITORING

5/19/2015  |   10:45 - 11:00   |  102B

RESPONSES OF RIVERINE MACROINVERTEBRATE COMMUNITIES TO ANTHROPOGENIC DISTURBANCE: IMPLICATIONS FOR BIOASSESSMENTS AND TRAITS-BASED MONITORING Although seeps, pools and channels in riverine corridors rarely provide permanent habitat, annual predictability has enabled many organisms to thrive in these areas. Dependence on stable groundwater, precipitation and temperature regimes makes these habitats vulnerable to both climatic and land use changes. Moreover, little is known about the communities adapted to these habitats, their responses to disturbance, and the importance of connectivity to other aquatic areas. We collected benthic macroinvertebrates in Pennsylvania headwater and floodplain complexes characterized by a mix of aquatic habitats and spanning an anthropogenic disturbance gradient. Using multivariate procedures, we identified community responses in flow pulse and floodplain/wetland habitats across this gradient and developed a Riverine Wetland Invertebrate Community Index. As forested systems shifted to more agricultural and urban settings with increasing hydrologic modification, sedimentation, and erosion, the extent and diversity of these habitats were reduced to instream habitats and disconnected permanent or ephemeral pools. The corresponding macroinvertebrate response was a shift from a diversity of EPT taxa with life history or behavioral traits to a dominance of semi-terrestrial and non-insect taxa with desiccation tolerance.

Susan Yetter (Primary Presenter/Author), Penn State University, sel131@psu.edu;


11:00 - 11:15: / 102B ENVIRONMENTAL DRIVERS OF TRAIT VARIATION IN DAMSELFLIES

5/19/2015  |   11:00 - 11:15   |  102B

ENVIRONMENTAL DRIVERS OF TRAIT VARIATION IN DAMSELFLIES Although variability among populations in morphological and life history traits is widely documented, the environmental drivers of this variability and its consequences for species coexistence are less well-understood. Understanding how and why traits vary among and within populations is essential to predict how species will respond to environmental changes. Damselflies in the genus Enallagma (Odonata: Coenagrionidae) exhibit a wide variety of morphological and life history traits throughout their range, making them good model organisms to study the environmental drivers of trait selection. We sampled Enallagma from 24 lakes throughout California, ranging from desert to alpine ecosystems. We calculated growth and mortality rates, and conducted morphometric analyses for each population. We used linear models to determine the relationship between local and regional environmental variables (e.g. temperature, elevation, latitude), phenotypic trait distributions, and estimates of selection. Our analyses reveal that local biotic conditions such as population density and the presence of fish predators are more important predictors of damselfly trait variation than regional environmental factors such as latitude and elevation. Biological interactions may be key drivers of selection in this genus.

Kate Boersma (Primary Presenter/Author), University of San Diego, kateboersma@sandiego.edu;


Adam Siepielski (Co-Presenter/Co-Author), University of San Diego, adamsiepielski@sandiego.edu;


11:15 - 11:30: / 102B REINTEGRATING THE AUTOTROPHIC BASE OF LAKES: FUNCTIONAL CONSEQUENCES OF CONTRASTING RESPONSES OF PHYTOPLANKTON AND PERIPHYTON COMMUNITY STRUCTURE TO FERTILIZATION

5/19/2015  |   11:15 - 11:30   |  102B

REINTEGRATING THE AUTOTROPHIC BASE OF LAKES: FUNCTIONAL CONSEQUENCES OF CONTRASTING RESPONSES OF PHYTOPLANKTON AND PERIPHYTON COMMUNITY STRUCTURE TO FERTILIZATION Consumers in aquatic ecosystems couple benthic and planktonic food chains with a gusto and ubiquity that the ecologists studying them fail to imitate. Benthic and planktonic microalgae are derived from a common taxonomic pool of protists and cyanobacteria, and are interacting functional guilds that form the autotrophic base of lake food webs. We assessed taxonomic similarity between benthic and planktonic algae over 4 years in 4 lakes, 3 of which were experimentally fertilized. Mean within-lake similarity between benthic and planktonic communities at the division level was 14%. Planktonic communities exhibited high among-lake variability within years and high within-lake variability among years at both the division and genus level. Total planktonic biovolume increased with fertilization. In contrast, benthic communities were co-dominated by diatoms, cyanobacteria and chlorophytes in all lakes in all years. Benthic algal total biovolume and species composition was unrelated to fertilization regime. The temporal stability of the benthic algal community combined with the consistently high contribution of PUFA-rich diatoms to total benthic algal biovolume may help explain the widespread importance of littoral primary production to consumers.

Yvonne Vadeboncoeur (Primary Presenter/Author), Wright State University, yvonne.vadeboncoeur@wright.edu;


Thomas Rooney (Co-Presenter/Co-Author), Wright State University, thomas.rooney@wright.edu;


David Lodge (Co-Presenter/Co-Author), University of Notre Dame, lodge.1@nd.edu;


11:30 - 11:45: / 102B TRAIT CHARACTERISTICS AS DETERMINANTS OF METAL EXPOSURE AND UPTAKE IN STREAM INVERTEBRATES

5/19/2015  |   11:30 - 11:45   |  102B

TRAIT CHARACTERISTICS AS DETERMINANTS OF METAL EXPOSURE AND UPTAKE IN STREAM INVERTEBRATES Relations between whole-body metal concentrations and species traits were examined for 40 invertebrate taxa in a mining-impacted river to determine 1) the extent to which trait-based characteristics accounted for species-specific differences in metal exposure and uptake, and 2) which traits were most effective in identifying exposure pathways and predicting uptake potential. Traits related to developmental strategies (e.g., generations per year) and habitat use (e.g., fluvial and substrate preferences) generally were poor predictors of metal bioaccumulation. In contrast, metal uptake was positively related to chemical and physical stressor tolerances. Comparison of feeding trait affinities and metal bioaccumulation patterns showed that feeding behavior was the strongest predictor of metal uptake among the traits examined. Metal concentrations increased in taxa relying on filtering or gathering as part (>40%) of their food acquisition strategy. Concentrations decreased where predation assumed a greater proportion of overall feeding activity. Application of trait characteristics as predictive tools may help identify taxon or taxa groups that may be at greatest risk in metal-disturbed environments.

Terry Short (Primary Presenter/Author), U.S. Geological Survey, Menlo Park, CA, tmshort@usgs.gov;


Michelle Hornberger (Co-Presenter/Co-Author), U.S. Geological Survey, Menlo Park, CA, mhornber@usgs.gov;


11:45 - 12:00: / 102B WATER SCARCITY AND FLOW REDUCTION: UNFORESEEN INDUCED ANOXIA AND HYPOXIA EFFECTS ON STREAM INVERTEBRATES

5/19/2015  |   11:45 - 12:00   |  102B

WATER SCARCITY AND FLOW REDUCTION: UNFORESEEN INDUCED ANOXIA AND HYPOXIA EFFECTS ON STREAM INVERTEBRATES Flow reduction generated by human activities, including climate change and water scarcity, can alter abiotic and biotic properties of stream ecosystems. We tested the response of invertebrates to complete flow suppression by damming longitudinally two small lowland streams. We sampled benthic invertebrates in control, and impact stretches (stagnant and drought) before and after the establishment of the dam during 10 weeks in summer. Oxygen dataloggers were weekly fixed for 24 hours at each control and two impacted stretches simultaneously. Flow reduction caused a sudden decrease in dissolved oxygen values (reaching anoxia and hypoxia) with great daily fluctuation varying with stream and stretch. TITAN invertebrate indicator taxa responded with differential sensitivity to oxygen reduction, some declining already at a minimum of 7.3 mg O2/l, others at 6.1 mg O2/l and 4 mg O2/l. Taxa traits confirmed significant decline in the density of forms respiring with tegument, gills and of those using plastron, while a significant increase for air breathing taxa. Results warn on potential unforeseen anoxia and hypoxia impacting stream invertebrates in the face of water scarcity and associated flow reduction.

Isabel Pardo (Primary Presenter/Author), Universidade de Vigo, ipardo@uvigo.es;


Liliana Garcia (Co-Presenter/Co-Author), Universidade de Vigo, lilizar@uvigo.es;