Date of Award

2013

Degree Name

Biological Sciences

College

College of Science

Type of Degree

M.S.

Document Type

Thesis

First Advisor

Thomas K. Pauley

Second Advisor

Jayme Waldron

Third Advisor

Frank Gilliam

Fourth Advisor

Suzanne Strait

Abstract

The Eastern Box Turtle, Terrapene c. carolina, is a terrestrial species native to the eastern United States. Once considered common, it is currently declining in much of its range due to habitat destruction and disease. To conserve the species, knowledge of Eastern Box Turtle habitat selection and the factors influencing their movement is necessary. Although the home range behavior of the Eastern Box Turtle has been well studied, few studies have quantified habitat selection at the home-range scale. Therefore, I examined home-range selection and within home range habitat selection in a population of Eastern Box Turtles at Hungry Beech Nature Preserve, in Roane County, West Virginia. I tracked 10 turtles from May to October 2012 approximately twice weekly. I assigned habitat categories to each turtle’s location based on field observations and aerial images. Using LoCoH, I estimated home range for each turtle. I examined habitat selection at the home-range scale and within the home range using binary logistic regression using habitat type, proximity to creek-associated habitat, slope, and aspect as predictor variables. In addition, I conducted a mark recapture study at the preserve. I opportunistically captured turtles throughout the preserve and uniquely marked them using shell notching. I estimated sex ratio, total population and population density at the preserve. I compared my results with estimates from a 1996 study. I also estimated apparent survival of individuals marked in 1996.

My results suggested that habitat type, proximity to aquatic habitat, and slope influence Eastern Box Turtle home-range selection. Specifically, turtles did not include aquatic habitats in their home ranges in proportion to their availability. Turtles selected steeper slopes in their home ranges, and avoided field habitat. However, my results suggested that turtles in areas with increased slopes may have had smaller home ranges. The inclusion of steep habitats could be caused by turtles moving around steep areas and inadvertently including them in their home ranges. Within home ranges, turtles selected habitats associated with the creek and mixed forest habitats. Eastern Box Turtles likely used creek-associated habitats to thermoregulate in extreme temperatures, and mixed forest habitat at the preserve contained a large amount of debris that may have been used as cover. Turtles may have selected habitats that contain a large amount of cover objects. Therefore, aquatic habitats and mixed forest habitats containing a large amount of cover should be considered when protecting Eastern Box Turtle habitat.

I estimated population size and density as 332 box turtles and 6 turtles/ha, respectively. Apparent survival was 66% since 1996. Average home-range size appears to have increased since 1996, likely due to successional habitat changes. My results suggest that sex ratio has become male skewed since 1996. The skewed sex ratio could be the result of increased female mortality, as I found more male survivors than females. However, future survival studies are necessary to conclude if female mortality is high at the preserve, or if sex ratio has changed due to changes in nesting behavior. My study has increased our knowledge of Eastern Box Turtle habitat requirements and habitat selection, and has shed light on long-term demographic shifts in a population of Eastern Box Turtles. The results of my study, as well as those from continued research at the preserve, may prove useful in future conservation efforts.

Subject(s)

Turtles - West Virginia.

Box turtle - West Virginia.

Hungry Beech Preserve (Roane County, W. Va.)

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