Current Research Projects
Flying Squirrel Bioacoustics Project
Flying squirrels (Glaucomys spp.) produce ultrasonic calls to communicate with conspecifics. Since these arboreal, nocturnal critters are typically difficult to monitor using traditional techniques (i.e., live traps, nest boxes), we are working on using this method to develop survey protocol using ultrasonic acoustics for monitoring flying squirrels, including the federally endangered Carolina northern flying squirrel (G. sabrinus coloratus). Working with Dr. Michelle Gilley, who discovered and characterized the ultrasonic calls of North American flying squirrels for her dissertation at Auburn University, we are currently conducting multiple projects with ultrasonic acoustics. Current projects include:
Past Projects include:
Current and past projects include: North Carolina Wildlife Resources Commission, U.S. Fish and Wildlife Service, Monongahela National Forest, Blue Ridge Parkway, San Diego Natural History Museum, Pennsylvania Game Commission, Great Smoky Mountains National Park, and Great Smoky Mountains Conservation Association. Additional support for these projects comes from U.S. Forest Service and USGS Virginia Cooperative Fish and Wildlife Research Unit. |
Appalachian Cottontail Project
In collaboration with Warren Wilson and Tangle Bank Conservation, LCC, we are looking at the distribution, habitat use, and population genetics of Appalachian cottontail (Sylvilagus obscurus) in western North Carolina. Little is know about this species and it is considered a state and federal species of concern. Our project aims to fill data gaps on this species at the most southern end of its range. Our project includes telemetry and scat surveys, which will be modeled to determine range-wide distribution and habitat use. Current funder of this project is the North Carolina Wildlife Resources Commission. |
Southwest Bat Acoustic Project
With White-nose Syndrome's (WNS) imminent spread to the southwestern United States, information is need to determine pre-WNS bat species distribution and ecology. There are large data gaps within the eastern part of the Colorado Plateau. I am currently working with the National Park Service units, Bureau of Land Management, and the Navajo Nation to increase understanding of the bat communities in these areas. Therefore, I am conducting a landscape-scale acoustics project with 109 sites in Utah and Arizona to help determine distribution, habitat use, and year-round activity patterns of southwestern bats. Participants in this study includes:
Current funder of this project is the National Park Service and U.S. Fish & Wildlife Service. |
Appalachian Flying Squirrel Climate Change Project
The federally endangered Carolina northern flying squirrel (Glaucomys sabinrus coloratus) and the recently de-listed Virginia northern flying squirrel (G. s. fuscus) live in high-elevation spruce-fir forests in the Appalachian Mountains. These forests have been reduced in size due to past industrial logging and fires, and have further been degraded by acid precipitation and introduced pests such as the balsam woolly adelgid. The biggest threat to these Pleistocene relic forests is climate change, as these forests already occupy the highest elevation peaks and ridgelines in the region. To better access the threat of climate change, I am modeling multi-decade nest box, live trapping, acoustic, and camera trap data to determine an integrate species distribution model for both subspecies. I will then model different climate scenarios to determine how this highly isolated, ecological unique subspecies will fare under a changing climate. Current funder of this project is the U.S. Fish and Wildlife Service. |
Past Research Projects
Appalachian Flying Squirrel Habitat Use
Both Virginia and Carolina northern flying squirrels are associated with high-elevation red spruce (Picea rubens)-northern hardwood forests in the central and southern Appalachians. However, a debate still lingers as to which habitat type is more critical to their survival: red spruce stands or northern hardwood stands. We aim to answer this question for both subspecices looking at data from radio-collared individuals to determine resource utilization functions on a landscape level. Additionally, we are conducting the first extensive home range and denning study on Carolina northern flying squirrels and the first foraging microhabitat study on Virginia northern flying squirrels. Funding for this project is provided by the North Carolina Wildlife Resources Commission, NPS Blue Ridge Parkway, USFWS Asheville Field Office, and the West Virginia Division of Highways. |
Endangered Spruce-fir Moss Spider Habitat Occupancy and Survey Impact
The spruce-fir moss spider (Microhexura montivaga) is one of four arachnids listed as federally endangered. The spider is endemic to high-elevation spruce-fir forests in the southern Appalachians. This species is inherently difficult to study because it resides between the interface of bryophyte mats and the rocks the bryophytes grown on. Determining the spider's presence requires partially destroying its habitat by physically removing portions of the bryophyte from the rock. Replacement of the mats does not assure they will reestablish and no study has quantified survey effects on habitat. Therefore, current survey methods have an unknown effect on spider habitat and populations, making regular monitoring difficult. Additionally, only general information about factors influencing habitat occupancy has been collected, but not estimated over the range of the spider. The objectives for this project are to 1) assess how survey technique influences bryophtye re-establishment, 2) determine detection probability and occupancy of spiders across multiple high-elevation spruce-fir recovery areas, 3) create a range-wide occupancy probability map for the spider based on habitat occupancy rates, and 4) create a standardized protocol for surveying that reduces negative impacts on the spider. Funding for this project is provided by the U.S. Fish and Wildlife Service Asheville Field Office. |
Utilization of Camera Traps to Survey Squirrels
Camera traps have traditionally been used to survey for carnivores, ungulates, and raptors, but there is potential to use this technique to survey for arboreal mammals, such as squirrels. We are conducting exploratory research to determine the protocol and methods for using camera traps to assess populations of squirrels. We use this technique to assess habitat occupancy and activity patterns for red squirrels, eastern chipmunk, southern flying squirrels, and northern flying squirrels. Portions of this project are funded by Virginia Tech and the North Carolina Wildlife Resources Commission. |
White-nose Syndrome and Activity Levels of Bats at Hibernacula
Across the eastern United States, White-nose Syndrome (WNS) has caused drastic declines in populations of multiple species of cave dwelling bats. Individuals infected with WNS may display unusual behavior, such as increased activity levels with and outside of the hibernacula during periods when the bats should be hibernating. We conducted a study looking at internal and external bat activity using ultrasonic acoustics at three caves in North Carolina with varying levels of WNS infection, including a confirmed site, a site adjacent to a WNS positive county, and a site isolated from WNS counties. We found a spike in internal activity prior to spikes in external activity. Standardized activity levels varied between the caves, with the highest activity occurring at the isolated site. Activity was higher during the nighttime versus the daytime. Monitoring hibernacula with ultrasonic acoustics may be beneficial to early detection of WNS. This project was funded by the USGS Virginia Cooperative Fish and Wildlife Research Unit. Additional equipment was provided by the North Carolina Wildlife Resources Commission and the U.S. Fish and Wildlife Service Asheville Field Office. |
Modeling Future Management Scenarios in a Ponderosa Pine Forest with Climate Change
Ponderosa pine (Pinus ponderosa) forests are being restored across the southwestern United States using selective thinning and prescribed fire to increase ecosystem function and resilience. The first large-scale Ponderosa pine ecological restoration site was implemented on the northern rim of the Grand Canyon at the Mount Trumbull Restoration Site. For my master's project, I modelled forest change under different climate scenarios for 100 years on ponderosa pine landscapes in the south-western USA, comparing management regimes that included prescribed burning, tree cutting, and no-management. We applied the Forest Vegetation Simulator (1) in its standard form, and (2) with modifications of reduced tree growth and increased mortality to simulate the effects of two levels of climate change. Without climate change effects, several management regimes, including the use of frequent burning similar to the historical fire frequency (5 year), maintained future forest structure within a target range of variability. In contrast, simulations that accounted for climate change effects indicated that burning intervals should be lengthened (20 year) and future tree thinning should be avoided to minimize forest decline. Although it has been widely predicted that future climate conditions will support more burning (warmer, drier fuels, longer fire season), our modelling suggests that the production of fuels will decline, so there will eventually be a trade-off between increased fire, driven by climate, v. reduced fuel, also driven by climate. This project was funded by the Joint Fire Science Program. |
Effects of Ponderosa Pine Restoration on Avifauna
Ponderosa pine (Pinus ponderosa) forests in the Southwestern United States have been degraded over the last century by fire suppression, logging, and grazing, causing increases in stand density, fuel loads, and the risk of large, stand-replacing fires. Ecological restoration utilizes thinning and prescribed burning to reduce stand density, increase structural diversity and herbaceous understories similar to those prior to Euro-American settlement. Proposals to restore over 970,000 ha of these forests in Arizona may be concerning because little is known about wildlife responses to landscape-scale restoration. For my master's prject, I assessed changes in bird occupancy and detection for 12 species at a large (1,200 ha) restoration site from 1996-1997 (2-5 years pre-treatment) to 2007-2008 (4 to 8 years post-treatment) in northern Arizona using a before-after control-impact design. Individual species responses (4 positive, 6 neutral, 2 negative) were consistent with our observations of changes in habitat conditions and the influences of habitat conditions on occupancy by each species. Restoration treatments should manage for important habitat components for birds, including Gambel oak (Quercus gambelii), snags, and downed woody debris. Continued monitoring of avifauna throughout restoration efforts is important because forests are typically not considered restored after one application of treatment and wildlife responses should help guide management of restored sites. This project was funded by Arizona Department of Game and Fish and the Ecological Restoration Institute. |