Back to top

SFS Annual Meeting

Tuesday, May 22, 2018
11:00 - 12:30

<< Back to Schedule

11:00 - 11:15: / 320 THE INFLUENCE OF RIVER ALTERATION ON SALMONFLY EMERGENCE PHENOLOGY

5/22/2018  |   11:00 - 11:15   |  320

THE INFLUENCE OF RIVER ALTERATION ON SALMONFLY EMERGENCE PHENOLOGY River alteration through impoundment, land-use changes, and development modifies water temperature regimes, which can in turn alter the duration, magnitude, and spatial patterning of resource pulses. We examine how human alteration and corresponding changes in thermal regime influence the emergence phenology of a large aquatic insect, the salmonfly (Pteronarcys californica), on two rivers of contrasting human activity in southwest Montana. On the Madison River, which is impounded and flows through an agricultural valley, water temperatures transition gradually along a gradient from cool upstream to warm downstream sites. In response, emergence moves in a predictable wave propagating downstream to upstream (Peak emergence ~ River mile: R2=0.96). In contrast, water temperature is discontinuous along a downstream-upstream gradient on the free-flowing, forested Gallatin River. The resultant emergence occurs less sequentially, with emergence at certain upstream sites occurring simultaneously or previous to emergence at downstream sites (Peak emergence ~ River mile: R2=0.35). Emergence duration also differed, lasting 30% longer on the Gallatin River. Future work will investigate how variations in salmonfly emergence duration and spatial patterning influence mobile and immobile consumers’ ability to utilize and track this resource pulse over space and time.

Heidi Anderson (Primary Presenter/Author), Montana State University, heidieliseanderson@gmail.com;


Lindsey Albertson (Co-Presenter/Co-Author), Montana State University, lalbertson@stroudcenter.org;


Presentation:
This presentation has not yet been uploaded.

11:15 - 11:30: / 320 HYDROLOGIC, MORPHOLOGIC, AND WATER QUALITY EFFECTS OF RURAL DEVELOPMENT IN STREAMS OF THE SOUTHERN BLUE RIDGE MOUNTAINS

5/22/2018  |   11:15 - 11:30   |  320

HYDROLOGIC, MORPHOLOGIC, AND WATER QUALITY EFFECTS OF RURAL DEVELOPMENT IN STREAMS OF THE SOUTHERN BLUE RIDGE MOUNTAINS Studying effects of low-density rural development on aquatic systems can elucidate the role of stream stressors on water quality in the absence of large-scale hydrologic changes. We conducted several cross-landscape studies of streams in the exurbanizing but largely rural landscape of the southern Appalachians. Valleys typically feature small farms, rural residences, and riparian alteration, whereas hillslopes feature mature forests with occasional intrusions by recent mountain developments. The region has high topographic and mesoclimate variability. Conversion of forested riparian zones to pastures or grasses profoundly changed channel structure by reducing channel widths and the frequency of step features. Wood counts were low in all streams with nearby human habitation, apparently due to direct wood removal. Sediment yields increased with basin development, the exception was the one urban stream with very low sediment yields. Big river sites suggested continued mobilization of legacy sediments. Specific conductance was idiosyncratic and not well correlated with basin land use. Catchment disturbance strongly influenced dissolved inorganic nitrogen (DIN) export and modified the seasonal pattern of DIN concentration. Water quality changes wrought by low density rural development influenced the presence/absence of focal native stream taxa.

C. Rhett Jackson (Primary Presenter/Author), University of Georgia, rjacks@uga.edu;


Jackson R. Webster (Co-Presenter/Co-Author), Department of Biology, Virginia Tech, Blacksburg, VA, jwebster@VaTech.edu;


Kristen Cecala (Co-Presenter/Co-Author), University of the South, kkcecala@sewanee.edu;


John R. Frisch (Co-Presenter/Co-Author), University of Minnesotat Duluth, jrfrisch@yahoo.com;


Joseph Kirsch (Co-Presenter/Co-Author), USDA Forest Service, josephkirsch@fs.fed.us;


John Maerz (Co-Presenter/Co-Author), University of Georgia, jcmaerz@uga.edu;


David S. Leigh (Co-Presenter/Co-Author), University of Georgia, dleigh@uga.edu;


Nick Peterson (Co-Presenter/Co-Author), MN Dept of Natural Resources, nick.peterson@state.mn.us;


Catherine Pringle (Co-Presenter/Co-Author), Odum School of Ecology, University of Georgia, cpringle@uga.edu;


Jennifer Knoepp (Co-Presenter/Co-Author), US Forest Service, Southern Research Station, jknoepp@fs.fed.us;


Presentation:
This presentation has not yet been uploaded.

11:30 - 11:45: / 320 ARTIFICIAL NIGHT LIGHTING IMPACTS RESOURCE EXCHANGE ACROSS AN AQUATIC-TERRESTRIAL BOUNDARY

5/22/2018  |   11:30 - 11:45   |  320

ARTIFICIAL NIGHT LIGHTING IMPACTS RESOURCE EXCHANGE ACROSS AN AQUATIC-TERRESTRIAL BOUNDARY Artificial night lighting (ANL) has increased concurrently with human habitation along freshwater shorelines, illuminating littoral and riparian areas. Do alterations to the natural light regime alter resource exchange between these highly productive ecosystems? To help answer this question, we installed 20 mesocosms in the littoral zone of Haven Hill Lake (Michigan, USA), manipulated the presence of fish and ANL, and measured a suite of community- and ecosystem-level parameters. We found that ANL increased emergent invertebrate abundance and altered emergent and terrestrial invertebrate community composition, while having few effects on aquatic benthic invertebrate communities and ecosystem processes. ANL also increased the presence of riparian spiders (Tetragnathidae) by 101% and spider biomass by 51%, with both biomass and abundance positively correlated with invertebrate-prey abundance. These results indicate that ANL along shorelines and in littoral zones can impact the transfer of resources across the aquatic-riparian boundary, and the consumers that utilize those resources.

Elizabeth Parkinson (Primary Presenter/Author), Dept. Biological Sciences, Oakland University, emparkinson@oakland.edu;


Scott Tiegs (Co-Presenter/Co-Author), Oakland University, tiegs@oakland.edu;


Presentation:
This presentation has not yet been uploaded.

11:45 - 12:00: / 320 STREAM BASAL RESOURCES EXHIBIT SHORT-TERM RESILIENCE FOLLOWING REACH-SCALE REMOVAL OF A DOMINANT RIPARIAN SHRUB

5/22/2018  |   11:45 - 12:00   |  320

STREAM BASAL RESOURCES EXHIBIT SHORT-TERM RESILIENCE FOLLOWING REACH-SCALE REMOVAL OF A DOMINANT RIPARIAN SHRUB Detrital and algal resources in headwater streams are strongly influenced by associated riparian vegetation. Understanding stream ecosystem resilience to alteration in riparian species composition is increasingly important, as dominant riparian species continue to be functionally extirpated by insects and disease globally. In the southern Appalachians, riparian eastern hemlock trees have undergone significant mortality, leading to increased growth of the evergreen shrub, Rhododendron maximum. Rhododendron removal is a potential management strategy to restore hardwood forests since it inhibits tree recruitment and growth. Here we assess the resilience of stream basal food resources in headwater streams to a reach-scale (300m) removal of rhododendron along four streams (2 reference, 2 treatments: cut, cut+burn). Treatments increased benthic sediment by 2-7 fold and reduced canopy cover 33-43% (deciduous leaf-off) . However, algal quantity (chlorophyll a), algal quality (C:N ratio), and benthic leaf litter quantity were unaffected. Higher litter quality was observed in late summer and early fall of both years, but not year-round. Short-term, stream basal resources in these headwater streams appear to be resilient to rhododendron removal at the reach-scale despite large changes in abiotic conditions.

Seth Wenger (Co-Presenter/Co-Author), Odum School of Ecology, University of Georgia, swenger@uga.edu;


C. Rhett Jackson (Co-Presenter/Co-Author), Warnell School of Forestry and Natural Resources, University of Georgia, RJACKSON@warnell.uga.edu;


Katherine Elliott (Co-Presenter/Co-Author), USDA Forest Service, Southern Research Station, Center for Forest Watershed Research, Coweeta Hydrologic Laboratory, kelliott@fs.fed.us;


Chelcy Miniat (Co-Presenter/Co-Author), USDA Forest Service, Southern Research Station, Center for Forest Watershed Research, Coweeta Hydrologic Laboratory, cfminiat@fs.fed.us;


Catherine Pringle (Co-Presenter/Co-Author), Odum School of Ecology, University of Georgia, cpringle@uga.edu;


Maura Dudley (Primary Presenter/Author), Oglethorpe University, maurapdudley@gmail.com;


Presentation:
This presentation has not yet been uploaded.

12:00 - 12:15: / 320 ECOLOGICAL FACTORS CONTROLLING INSECT-MEDIATED METHYLMERCURY FLUX FROM AQUATIC TO TERRESTRIAL ECOSYSTEMS

5/22/2018  |   12:00 - 12:15   |  320

ECOLOGICAL FACTORS CONTROLLING INSECT-MEDIATED METHYLMERCURY FLUX FROM AQUATIC TO TERRESTRIAL ECOSYSTEMS The diets of terrestrial consumers can be subsidized by energy and nutrients transported from aquatic ecosystems to terrestrial food webs by emergent aquatic insects. However, the cross-system transport of materials by insects can have a “dark side” because emergent aquatic insects also transport toxic contaminants such as methyl mercury (MeHg) to terrestrial ecosystems (hereafter referred to as insect-mediated MeHg flux). Although ecological factors are known to influence insect emergence and the cross-system transport of energy and nutrients by insects, the ecological factors regulating insect-mediated MeHg flux have been little studied. In this presentation we overview our mesocosm and pond experiments examining ecological factors regulating the transport of MeHg out of aquatic ecosystems by emergent insects. We also present a conceptual model integrating the influence of MeHg contamination of ecosystems and ecological factors regulating emerging insect-mediated MeHg flux during seasons when insects are emerging. We propose that the potential for insect-mediated MeHg flux increases with Hg contamination of the ecosystem but that the realized insect-mediated MeHg flux is determined by ecological factors known to regulate aquatic insect community ecology.

Matthew Chumchal (Primary Presenter/Author), Texas Christian University, m.m.chumchal@tcu.edu;


Ray Drenner (Co-Presenter/Co-Author), Texas Christian University, r.drenner@tcu.edu;


Presentation:
This presentation has not yet been uploaded.

12:15 - 12:30: / 320 AERIAL INSECTIVOROUS BIRDS: CONSERVATION ACROSS THE LAND-WATER INTERFACE

5/22/2018  |   12:15 - 12:30   |  320

AERIAL INSECTIVOROUS BIRDS: CONSERVATION ACROSS THE LAND-WATER INTERFACE Aerial insectivorous birds – swifts, swallows, flycatchers, and nightjars – have experienced alarming population declines in eastern North America. Declines have occurred across the guild, despite a wide diversity of life histories, habitats, and taxonomy, pointing to flying insect prey as a common factor in these declines. Emergent aquatic insects, commonly sensitive to changes in water quality, are a key food resource for many aerial insectivores. To explore potential links between water quality and aerial insectivorous bird reproductive success and body condition, we installed nestboxes and monitored Tree Swallow (Tachycineta bicolor) body condition and reproductive success, assemblages of flying insects (aquatic and terrestrial), and water-chemistry parameters at 7 river reaches in greater Columbus, Ohio over consecutive breeding seasons (2014-2017). Water temperature was related to both the density and family richness of emerging aquatic insects. Total nitrogen, EPT relative abundance, and water temperature predicted the number of eggs and fledglings. The scaled mass index of body condition in adult swallows was strongly related to EPT relative abundance and water mercury concentrations. These initial findings implicate water quality as an important consideration in the conservation of riparian aerial insectivorous birds.

Joseph W. Corra (Primary Presenter/Author), The Ohio State University, corra.1@osu.edu;


S. Mažeika Patricio Sulliván (Co-Presenter/Co-Author), The Ohio State University, sullivan.191@osu.edu;


Presentation:
This presentation has not yet been uploaded.