Back to top

SFS Annual Meeting

Tuesday, May 22, 2018
09:00 - 10:30

<< Back to Schedule

09:00 - 09:15: / 410 A INTERSPECIFIC INTERACTIONS ARE CONDITIONAL ON TEMPERATURE IN AN APPALACHIAN STREAM SALAMANDER COMMUNITY

5/22/2018  |   09:00 - 09:15   |  410 A

INTERSPECIFIC INTERACTIONS ARE CONDITIONAL ON TEMPERATURE IN AN APPALACHIAN STREAM SALAMANDER COMMUNITY Differences in the rates of responses to climate change has the potential to disrupt well-established ecological interactions among species. In semi-aquatic communities, competitive asymmetry based on body size currently maintains competitive exclusion and coexistence via interference competition. Elevated temperatures are predicted to have the strongest negative effects on large species and aquatic species. Our objectives were to evaluate the interaction between elevated temperatures and competitor identity on growth and habitat selection behavior of semi-aquatic salamanders in stream mesocosms. We observed interference competition between small and large species. Elevated temperatures had a negative effect on the larger species and a neutral effect on the smaller species. At elevated temperatures, the strength of interference competition declined, and the smaller species co-occupied the same aquatic cover object as the larger species more frequently. Disruptions in competitive interactions of this community may affect habitat use patterns and decrease selection for character displacement among species. Determining how biotic interactions change along abiotic gradients is necessary to predict the future long term stability of current communities.

Mary Lou Hoffacker (Co-Presenter/Co-Author), Georgia Environmental Protection Agency, marylou.hoffacker@dnr.ga.gov;


Josh Ennen (Co-Presenter/Co-Author), Tennessee Aquarium Conservation Institute, jre@tnaqua.org;


Shawna Mitchell (Co-Presenter/Co-Author), Tennessee Aquarium Conservation Institute, smitchell@tnaqua.org;


Jon Davenport (Co-Presenter/Co-Author), Appalachian State University, davenportjm@appstate.edu;


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


Presentation:
This presentation has not yet been uploaded.

09:15 - 09:30: / 410 A THE INFLUENCE OF WINTER SEVERITY ON THE COUPLING BETWEEN LAKE ERIE LARVAL WALLEYE AND THEIR PREY

5/22/2018  |   09:15 - 09:30   |  410 A

THE INFLUENCE OF WINTER SEVERITY ON THE COUPLING BETWEEN LAKE ERIE LARVAL WALLEYE AND THEIR PREY Due to climate warming, winter ice in the Laurentian Great Lakes has declined by 71% over the past four decades (Wang et al. 2012). Walleye recruitment in Lake Erie, which shows a positive relationship with winter ice cover, has been consistently low since 2003, except following the extremely cold winter of 2015. Here, we examine the hypothesis that warm winters result in a temporal mismatch between walleye larvae and their zooplankton prey. We evaluated this hypothesis with Western Basin Lake Erie zooplankton data from 2011-2016. Following the record warm winter in 2012, walleye spawning occurred much earlier than in normal years; our results showed that zooplankton spring blooms also occurred earlier in 2012. Across all years, the biomass of walleye preferred zooplankton prey (Cyclopoids and small Cladocerans) had relatively low densities during the period when larval walleye consume zooplankton, regardless of winter severity. Our results suggest that warm winters are not resulting in temporal decoupling of walleye larvae and their preferred zooplankton prey.

Amara Huddleston (Primary Presenter/Author), The Ohio State University, huddleston.75@osu.edu;


Cassandra May (Co-Presenter/Co-Author), Bethel College, osu.265@gmail.com;


Joshua Stone (Co-Presenter/Co-Author), The Ohio State University, stone.768@osu.edu;


Stu Ludsin (Co-Presenter/Co-Author), The Ohio State University, ludsin.1@osu.edu;


Elizabeth Marschall (Co-Presenter/Co-Author), The Ohio State University, marschall.2@osu.edu;


James Hood (Co-Presenter/Co-Author), The Ohio State University, hood.211@osu.edu;


Presentation:
This presentation has not yet been uploaded.

09:30 - 09:45: / 410 A EVIDENCE OF THE TEMPERATURE-SIZE RULE IN CHIRONOMIDAE FROM UTQIAGVIK (BARROW), ALASKA: IMPLICATIONS FOR A WARMING ARCTIC

5/22/2018  |   09:30 - 09:45   |  410 A

EVIDENCE OF THE TEMPERATURE-SIZE RULE IN CHIRONOMIDAE FROM UTQIAGVIK (BARROW), ALASKA: IMPLICATIONS FOR A WARMING ARCTIC The Temperature-Size Rule (TSR) states that as temperatures rise, ectothermic organisms decrease in size. This pattern has been documented across a wide range of taxa. Under global climate change, the TSR may be important in understanding how ecosystems are changing. Here we present laboratory evidence of the TSR in Chironomidae (non-biting midges) from the rapidly-warming Arctic. We reared 12 species (N>30 of each sex) under ten controlled-temperature treatments (4º-28ºC) from late larval development through pupation to emergence of the adult fly. As these species’ life cycle durations range from one to several years, individuals spent only a small percentage of their life cycle in these controlled conditions. Nonetheless, 6 out of 12 species showed significant adult size decrease in accordance with the Temperature-Size Rule, while five species showed no trend and one species showed a positive correlation between adult size and rearing temperature. Whether these species-specific patterns will be evident in the wild as the arctic growing season becomes longer and warmer is unknown.

Alec Lackmann (Primary Presenter/Author), North Dakota State University, alec.lackmann@ndus.edu;


Daniel McEwen (Co-Presenter/Co-Author), Limnopro Aquatic Science, Inc., dan@limnopro.com;


Malcolm Butler (Co-Presenter/Co-Author), North Dakota State University, malcolm.butler@ndus.edu;


Presentation:
This presentation has not yet been uploaded.

09:45 - 10:00: / 410 A THERMAL ADAPTATION ALTERS THE ECOLOGICAL ROLE OF CONSUMER BODY SIZE

5/22/2018  |   09:45 - 10:00   |  410 A

THERMAL ADAPTATION ALTERS THE ECOLOGICAL ROLE OF CONSUMER BODY SIZE Body size is a key factor that determines the ecological role of consumers. Body size is expected to decline with climate change. Does this mean that the ecological effects of consumer species will change in the future as body size distributions shift towards smaller individuals? The answer to this question depends on the extent to which ongoing thermal adaptation will alter the relationship between body size and ecological role. We addressed this issue by examining populations of fish which recently invaded geothermal systems of differing temperatures. We conducted a mesocosm experiment in which we manipulated source population and fish body size distribution while holding biomass steady. We measured a suite of ecological response variables ranging from zooplankton community composition to greenhouse gas emissions. Ecological responses to different body size distributions varied considerably among parameters, with some unresponsive to body size change, some showing similar response to size in both populations, and some showing highly divergent response to body size change between populations. Our results suggest that thermal adaptation can alter the ecological outcome of future body size declines.

Kevin Simon (Primary Presenter/Author), The University of Auckland, k.simon@auckland.ac.nz;


Emma Moffett (Co-Presenter/Co-Author), The University of Auckland, emma.moffett@auckland.ac.nz;


David Fryxell (Co-Presenter/Co-Author), University of California - Santa Cruz, dcfryxell@gmail.com;


Eric Palkovacs (Co-Presenter/Co-Author), University of California - Santa Cruz, epalkova@ucsc.edu;


Presentation:
This presentation has not yet been uploaded.

10:15 - 10:30: / 410 A VULNERABILITY OF FOUR ENDEMIC FISHES TO CLIMATE WARMING IN A TEMPERATE BIODIVERSITY HOTSPOT

5/22/2018  |   10:15 - 10:30   |  410 A

VULNERABILITY OF FOUR ENDEMIC FISHES TO CLIMATE WARMING IN A TEMPERATE BIODIVERSITY HOTSPOT Faunal vulnerability to climate warming depends on species-specific sensitivities and spatially-varying exposure to warming. Southern Appalachia is a hotspot for fish diversity, but little is known about interspecific variation in thermal biology or exposure to temperature extremes. We assessed thermal habitat and physiological tolerance, and forecasted distributional changes and warming tolerance of four endemic fishes (Notropis leuciodus, N. rubricroceus, Etheostoma rufilineatum, and E. chlorobranchium) that differ in elevational limits and represent the two most species-rich clades in the region. We used environmental niche modeling (ENM) to map species distributions, and combined thermal tolerance experiments with weather simulations to assess heat stress under contemporary and future climates. ENMs projected declines in suitable habitat and upslope shifts for all species except the low-elevation darter, E. rufilineatum, which is projected to expand its range into high-elevation streams. Extreme heat events never exceeded thermal tolerances under contemporary climate, but did at low elevations under future climates. Results suggest that thermal optima drive contemporary elevational limits of the four species, whereas both optima and maxima will likely drive future elevational shifts. Integrating physiological and distributional information provided complementary insight into contemporary and future species distributions.

Matthew Troia (Primary Presenter/Author), University of Texas San Antonio, troiamj@gmail.com;


Xingli Giam (Co-Presenter/Co-Author), University of Tennessee, xgiam@utk.edu;


Presentation:
This presentation has not yet been uploaded.