Committee Chair

Wilson, Thomas P.

Committee Member

Hossain, A.K.M. Azad; Gunasekera, Sumith; Reyonlds, Bradley R.


Dept. of Biological and Environmental Sciences


College of Arts and Sciences


University of Tennessee at Chattanooga

Place of Publication

Chattanooga (Tenn.)


Understudied high-biomass animals such as the Northern Zigzag salamander (Plethodon dorsalis) are known contributors to essential nutrient cycles within their respective habitats. Knowing that these sensitive creatures serve as bioindicators for the overall health and quality of many ecosystems, we should aim to comprehend their habitat requirements. Doing so could ultimately allow conservationists to set more accurate baselines for various mitigation and land management practices. Due to our location within the southeast amphibian biodiversity hot spot, sampling of P. dorsalis is conducted in the Tennessee River Gorge (TRG). Sampling of survey polygons began on October 28, 2018 and concluded on June 8, 2019. Three 2,000 m² sites are selected based on presence of target species and a GIS processed land cover dataset in an attempt to best represent the diverse landscape of selected slopes within the 27,000 acre TRG. Specimens are located using a time based natural cover object survey method. Microhabitat is analyzed within 1 m² of each location containing a P. dorsalis specimen along an elevation gradient (250-300, 300-350 and 350-400 m). For each animal-present location, a randomly selected animal-absent plot is analyzed. This assessment attempts to identify differences in microhabitat preference based on selected versus available habitat using predictive geospatial models and AICc values. These AICс values demonstrate the performance of covariates measured and model fit in relation to salamander presence. Results suggest that different factors influence the distribution of P. dorsalis with respect to microhabitat selection.


I would like to start by thanking my committee members Dr. Hossain, Dr. Gunasekera, and Dr. Reynolds for their patience, support, and guidance. Their input has been critical to my success in developing my thesis. Many Team Salamander members, friends and peers were kind enough to take time out of their lives to support my work as well. John Shelton assisted with ground-truthing to confirm land cover types. Rick Blanton provided assistance with spatial data acquisition. Field survey volunteers included Michael Ashcraft, Rachel Head, Garrett Holder, Jarid Prahl, Katie Quast, Bianca Bradshaw, Sarah Kelehear, Kelly Daniels, Paul-Erik Bakland, Tanner Gatlin, Cassandra Gilmore, Cullen Harris, Nate Parrish and Erin Taylor. Breanna McDevitt deserves special mention as the most consistent and most patient member of my field survey team. She has endured the bulk of challenging field conditions met during this work. Tucker Clark and Yatri Patel wrote, modified, and explicated a Python script to help me transform my data for analysis. Daley Harrison was my first ever research partner during my undergraduate work. Her partnership gave me the confidence to peruse challenges I never would have tried to face alone. Nyssa Hunt has provided assistance in nearly every aspect of this project. Her guidance and unwavering patience is a primary reason for my skill development with GIS and overall morale. Nyssa has consistently been a fantastic friend, lab mate and teacher. Chris Manis and John Lugthart are the reasons I even considered applying to graduate school. Their dedication as my undergraduate research advisors and mentors has been incredibly valuable. They provided me with the opportunities I needed to develop my own intrinsic value in the research sciences. Dr. Wilson, as my graduate advisor and mentor, has guided me through the most challenging years of my life. I will never be able to thank him enough for his time and dedication. Without him, I would never have gotten this far. He truly taught me what it means to be a great scientist.


M. A.; A thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Master of Arts.




Conservation biology; Niche (Ecology); Salamander populations


Tennessee River


Ecology; Salamander microhabitat; Tennessee river gorge; GIS

Document Type

Masters theses




xiii, 67 leaves