CFAES Give Today

School of Environment and Natural Resources


The Wildlife Society and American Fisheries Society Combined Conference

School of Environment and Natural Resources Terrestrial Wildlife and Ecology Lab (TWEL) Faculty and Graduate Student Presenters at The Wildlife Society and American Fisheries Society Joint Conference, September 29 to October 3, 2019, Reno, NV.

Contributed Papers

October 1, 2019


Who to hear from and how? Understanding different social science methods to improve fish and wildlife decision-making


Lara Mengak, Alia Dietsch, Ashley Dayer, Natalie Sexton


Many social science research methods exist for gathering input from diverse stakeholders to support fish and wildlife management decision-making. However, it is often unclear which methods are best suited for different types of decision processes. This talk highlights two case studies representing distinct methods of gathering input as part of manager decision-making. The first case study highlights the Delphi technique, an iterative consensus-building social science method used to bring together diverse groups of experts or stakeholders to achieve a convergence of opinion on a topic. Specifically, we demonstrate how the Delphi technique resulted in a consensus definition of human disturbance to shorebirds among experts and a list of priority disturbance types that affect migratory shorebirds. The second case study highlights the role of data collected quantitatively as part of a multi-wave survey of visitors (n > 15,000) to national wildlife refuges spanning the U.S. Results from a nonresponse check as part of this effort underscore the importance of appropriately representing the population(s) of interest when informing decision-making. Both case studies demonstrate the role of appropriate methods to address complex management decisions and ultimately ensure that decisions are informed and, when necessary, supported by a diverse group of users.


October 2, 2019


Movements of Virginia Rails and Soras within the Western Lake Erie Basin


Nicole Hengst, James Hansen, Brendan Shirkey, John Simpson, Robert Gates


Since the 1850s most of the coastal wetlands within the western Lake Erie basin have been drained and lost to agriculture and development. Today the majority of remaining wetlands are impounded and managed to produce food and cover for waterfowl. While managed wetlands are an important source of rail habitat in Ohio, little is known about the movement of rails in these wetlands and how water level manipulation affects the movements of migrating and breeding rails. Virginia rails (Rallus limicola) and soras (Porzana carolina) were captured at Winous Point Marsh Conservancy located within the western Lake Erie basin in Ohio and fitted with VHF radio-transmitters and tracked daily during March-September, 2016-2019. Virginia rails were also fitted with nanotags and tracked using the Motus Wildlife Tracking System in 2018 and 2019. Tagged rails were detected at automated radio-telemetry towers surrounding Lake Erie in Ohio and across Canada, Michigan, New York, Pennsylvania, and New Jersey. Signals from 32% of radio-marked rails (n = 251) were lost within 1-2 days after capture during the breeding season. These rails appeared to move well beyond the marshes of the western Lake Erie basin suggesting that coastal wetlands are more important as migratory staging areas than breeding habitat. Of the 295 radio-marked rails that remained at the study site at least one day after capture, 74% only used the impoundment they were captured in, allowing us to examine rail movement patterns and probability of departure in response to changing water levels and vegetation structure and cover. This work will provide a better understanding of rail movements in wetlands with water level manipulation and aid in more informed wetland management for rail species in northern Ohio.





Factors Affecting Functional Landscape Connectivity in a Pool Breeding Amphibian Community


William Peterman, Stephen Matthews, Michael Graziano


Functional connectivity is essential for the long term persistence of populations on the landscapes. Numerous factors can affect the realized functional connectivity of habitats across the landscape including habitat structure, topographic features, and animal dispersal abilities. Management efforts that create or restore wildlife habitats are often reliant on natural colonization of species from the surrounding landscape. As such, an understanding of the factors affecting functional connectivity can be critical to ensuring that management efforts are successful. Unfortunately, functional connectivity can be exceedingly challenging to objectively quantify. The goal of our study was to assess functional connectivity in a pool breeding amphibian community within a continuously forested landscape. To do so, we constructed 14 ridgetop pools southeastern Ohio, USA, and recorded species colonization in those sites for two years. Using species abundance at created pools, we developed incidence function models to assess six competing hypotheses evaluating the role that distance to natural wetlands, slope between natural wetlands, and area of natural wetlands played in colonization of constructed pools. We found that connectivity for salamanders within our community was largely a function of distance and mean slope to wetlands, while anuran connectivity was not well-predicted by any of our models. Our results suggest that the creation of pools in locations that minimize distance and slope to occupied existing wetlands can facilitate connectivity for the greatest number of species. In doing so, the time to colonization may be reduced, and the number of individuals colonizing may increase. The addition of functionally connected breeding habitats on the landscape will increase metapopulation capacity and bolster population resilience, and should be carefully considered in future management or restoration efforts.


October 3, 2019


Evaluating Stream Salamander Distribution and Abundance Using a Community N-Mixture Model


Philip Gould


Identifying the patterns that drive the abundance of species and communities at broad spatial scales is a central question in ecology. Although, the influence of landscape characteristics is often associated with terrestrial habitat, these characteristics are of equal importance to aquatic ecosystems. Nowhere is this more noticeable than forested headwater ecosystems, where energy-flow and habitat dynamics are driven primarily by upland forest characteristics. These systems differ from lower elevation, higher order streams, as they are smaller and more reliant on exogenous resources. This reliance on allochthonous inputs, squarely places headwaters as part of riparian forest ecosystems, not independent of them. In the southern Appalachians, high elevation headwaters are dominated by salamanders, in the absence of fish. Salamanders play an important role in trophic processes and nutrient recycling, therefore, understanding how communities respond to water quality and broad scale habitat characteristics is important. Between May – August 2017, I surveyed 9 meters of 75 streams, on 3 separate occasions, in the Nantahala National Forest, to estimate the abundance of stream salamanders. We evaluated stream salamander abundance as a function of broad scale (elevation, canopy cover, slope, aspect, and stream order) and water quality metrics (pH, conductivity, average water temperature, and stream substrate), while accounting for detection. We modeled species responses using a community N-mixture model in R using package jagsUI. We found strong positive responses to elevation for the black-bellied salamander and negative responses to elevation for the Ocoee salamander. Additionally, we found strong negative responses to increased water temperatures for 3 of the 4 modeled species, with the seal salamander showing no significant negative response. Species richness was highest at sites with both intermediate elevation and slope values. These responses indicate that responses to habitat conditions are more related to life-history strategies than guild-level processes.



Contributed Posters

September 30, 2019, 5:00 to 9:00 PM

Habitat Use and Survival of Timber Rattlesnakes in Ohio’s Forestry Lands

Andrew Hoffman, Annalee Tutterow, William Peterman

Timber Rattlesnakes (Crotalus horridus) were once widespread, but populations are now fragmented, isolated, and in decline following a history of intense persecution and habitat loss. Many remaining populations occur on State and Federal Forestry lands that are subject to timber harvest and prescribed fire. We used radio-telemetry to track the movements, habitat use, and survival of 36 timber rattlesnakes in southern Ohio from 2016 to 2018 and characterized their use of habitat under varying management practices. During this time, we also detected Snake Fungal Disease (SFD) and recorded its prevalence among our telemetered animals. We observed an average annual mortality of 9% with predation or SFD associated with most mortalities. Telemetered rattlesnakes utilized all major habitat types, but their behavior physiologic needs dictated selection. Gestating snakes and snakes digesting recent meals or in ecdysis selected recent clearcuts and thinned plots while snakes foraged predominantly in mature forests and burned areas. Management resulting in a heterogeneous forest landscape with forest plots varying widely in age may provide a beneficial range of thermal and structural environments that allow snakes to thermoregulate and forage while limiting their exposure to predators. Our continued research will look more closely at how forest composition and structure effect prey availability and thermoregulation.



Applying AHDriFT to Survey for the Eastern Massasauga Rattlesnake in Northern Ohio

Evan Amber, William Peterman, Gregory Lipps

The Eastern Massasauga Rattlesnake (Sistrurus catenatus; hereafter, EMR) was listed as Federally Threatened in 2016. Wet prairie habitat loss is the principle driver of EMR decline. Areas that may contain populations must be adequately surveyed prior to development and where vegetation management may need to be applied. However, the EMR’s reclusive nature makes them difficult and costly to detect. Thus, there is government and private sector interest in more efficient survey methods. This research will develop the Adapted Hunt Drift Fence Technique (AHDriFT) to EMR surveys. The method uses inverted-bucket camera traps systems, specially designed to capture species-quality images of herpetofauna and small mammals, placed at the ends of drift fences. Original development in Florida was successful in capturing species diversity while dramatically lowering person-hours compared to traditional surveying. Our objectives include: • Identify technical issues with applying AHDriFT to wet prairie habitats, and test necessary modifications. • Compare the number and frequency of EMR images captured to the encounter rate of previous surveys and baseline population data. • Determine the covariates and effort related to detection of EMR using AHDriFT to the desired confidence of absence. • Create a cost-efficiency matrix comparing AHDriFT to the accepted survey protocol. We set 15 omni-directional AHDriFT arrays comprising 45 camera traps across 3 counties in northern Ohio where we have 3 years of robust EMR population data. We are maintaining detailed logs of construction, maintenance and processing effort. We are collecting environmental covariate data using iButton loggers, coupled with local weather station data and DIVAs. We will conduct image and model analyses in R, and spatial analyses using GIS. In only the first two weeks of deployment, prior to EMR emergence, we have obtained over 200 unique individual images of 10 species, including 7 Eastern Gartersnakes (Thamnophis sirtalis).