Contact Information

• Warnell School of Forestry and Natural Resources
• Athens, Georgia
• Room:3-322
• Phone:706.542.3929
• Fax:706.542.8356
• scastle@forestry.uga.edu

Education

• Ph.D. in Wildlife and Fisheries Resources, West Virginia University, 2000. Dissertation: Conservation and management of the Allegheny woodrat in the central Appalachians
• M.S. in Forest Resources, University of Georgia, 1997. Thesis: Herbivory and canopy opening size influences on forest regeneration in a southern bottomland hardwood forest
• B.S. in Forest Resources, University of Georgia, 1993. Major: Wildlife Biology

Research Areas

• Wildlife responses to forest management practices
• Ecology of bats in managed forest landscapes
• Wildlife population genetics

Courses Taught

Vertebrate Natural History (FORS/ECOL 3580)

This course provides students with an introduction to the study of fish, amphibians, reptiles, birds, and mammals, with emphasis on taxonomy and systematics, life history, behavior, and ecology. The lecture portion of the course focuses on systematics, basic life history, and adaptations of vertebrates. In the lab, the major emphasis is on the identification and natural history of regional vertebrate species. The course is designed to provide students in the wildlife biology major with a basic foundation needed for further study in vertebrate and wildlife biology.

Field Mammalogy (FORS 4050/6050)

This course is an in-depth study of mammalian biology and ecology with an emphasis on field methods. The lecture portion of the course covers mammalian diversity, biogeography, behavior, physiology, and ecology. The lab emphasis is on the identification, taxonomy, and natural history of southeastern mammals. A major part of the course focuses on methods used in the study of mammals, including collection and preparation of museum specimens.

Current Research Projects

Intensive Forest Management Impacts on Wildlife Habitat

In response to a variety of factors, management of loblolly pine in the southeastern United States has increased in intensity, incorporating increased use of herbicides, fertilizers, and genetically improved planting stock. Quantifying the response of vegetation and wildlife to herbicide mixtures and evaluating new approaches to minimize vegetative and wildlife impacts, while allowing continued improvement in pine plantation productivity, have been identified as research priorities by the forest product industry. The objective of this research is to quantify the effects of varying levels of management intensity on vegetative, small mammal, and breeding bird communities.

Response of Herpetofauna and Insectivores to Coarse Woody Debris Manipulation

Coarse woody debris (CWD), in the form of fallen logs and standing dead trees, may be an important component in controlling diversity and abundance of organisms in forest ecosystems. However, the response of these faunal communities to the absence or presence of CWD is not clear because of a paucity of manipulative studies designed to address mechanistic questions. The purpose of this research is to investigate the response of herpetofauna and shrews to experimental manipulations of downed and standing CWD volume in managed southeastern pine forests.

Bat Community Composition and Habitat Use at the New, Gauley, and Bluestone River National Park Areas, West Virginia

In response to anthropogenic impacts and alterations on many public lands, the National Park Service has initiated efforts to provide park managers with information needed to preserve ecosystem integrity in National Parks. The combination of protected forests, large riverine riparian zones, and extensive clifflines of the New River Gorge National River, the Gauley River National Recreation Area, and the Bluestone River National Scenic River in southern West Virginia provide habitat for a large number of bat species, including several species of conservation concern. The objectives of this research are to survey community composition, abundance, and distribution of bats at the park areas and to examine species-specific foraging habitat associations.

Bat Community Structure and Habitat Use on an Intensively Managed Landscape with Forested Corridors

Timber harvesting can have both positive and negative effects on bat populations. One strategy to mitigate loss of habitat due to intensive forest management is the creation and maintenance of forested corridors. Although studies have shown a relationship between corridors and foraging bats, the importance of corridors with respect to roost-site selection remains unknown. The objective of this study is to identify patterns in bat species composition, roost-site selection, and foraging activity in response to landscape-level forest management planning that retains forested corridors connecting older-aged stands with a mosaic of younger stands in varying successional stages.

Inter-nesting Habitat Use and Post-nesting Movements of Adult Loggerhead Turtles in Georgia

The southeastern United States loggerhead (Caretta caretta) population has declined over the last four decades, with inadvertent capture and drowning in shrimp trawls believed to be the single largest source of mortality. Little is known about the movements and habitat use of female loggerhead turtles during the inter-nesting life stage throughout the range. Information on movement patterns and habitat use during this critical and potentially vulnerable time period is necessary to identify and minimize anthropogenic sources of mortality, particularly those associated with commercial fisheries and dredging activity. This purpose of this research is to compare distribution and movement patterns of adult female loggerhead turtles during inter-nesting intervals with concurrent shrimp trawler distributions.

Wetland Predictors of Amphibian Species Diversity and Abundance

Isolated wetlands are of primary importance to the breeding ecology of many amphibian species in the Coastal Plain of the southeastern United States. However, the majority of the species also are dependent on adjacent terrestrial habitats for some part of their life cycle. The characteristics of these wetlands, as well as the surrounding terrestrial habitats, have a profound influence on amphibian communities. The purpose of this research is to identify characteristics of isolated wetlands and surrounding upland habitats that are related to amphibian diversity and abundance.

Assessment of Habitat Use by the Endangered Key Largo Woodrat

The total population of the Key Largo woodrat (Neotoma floridana smalli) has declined to perilously low numbers over the past 30 years. A variety of factors, including habitat loss and degradation, high raccoon densities, and exotic competitors and predators, are suspected to have contributed to the decline. Accurate information regarding habitat requirements for the species is critical for management of the remaining habitat and for potential creation of new habitat. The objective of this research is to identify critical habitat requirements for the Key Largo woodrat at the macro and microhabitat scales.

Genetic Structure of Wood Frog Populations in Fragmented and Unfragmented Landscapes

Vernal pools provide important breeding habitat for many woodland amphibians. Because most amphibians that breed in vernal pools spend the rest of their life cycle in surrounding upland habitat, alteration of surrounding habitat can have profound influence on amphibian populations. Habitat patches may become fragmented, preventing migration among patches necessary to maintain population structure. The wood frog (Rana sylvatica) is a vernal pool breeding anuran that represents an ideal model species for examining the impact of habitat fragmentation on the vernal pool breeding amphibian populations. The purpose of this research is to compare wood frog population genetic structure between fragmented and unfragmented landscapes using microsatellite DNA markers.