Date of Award

Spring 2021

Degree Name

Bachelor of Science


Environmental Science

First Advisor

Amber Pitt

Second Advisor

Christoph Geiss

Third Advisor

Jonathan Gourley


The understanding of competitive release and a generalist species’ ability to exploit an available niche assists in explaining short- and long-term changes in ecological communities. I evaluated the expansion and establishment of a native generalist species, the red-eared slider (Trachemys scripta elegans), into a river community studied over a 50-year period (1969-2019). My objective was to analyze the T. s. elegans population upon expansion and how the population has been affected by the short- and long-term changes of the ecosystem. The turtle community in the North Fork of the White River, Ozark County, MO, USA faced habitat degradation, harvesting, a record shattering flood resulting in changes to the riparian habitat, and other stressors. I concluded that the T. s. elegans population was able to expand their population into a new geographic area following the reduction of competition and increased basking habitat due to nuisance vegetation growth associated with habitat degradation. The short-term effects of flooding further benefited the expanding population of T. s. elegans by increasing nesting habitat. Within the 50-year period, the generalist species, T. s. elegans, was able to exploit and thrive in a small niche without harming the dominant species, the northern map turtle (Graptemys geographica).


Senior thesis completed at Trinity College, Hartford CT for the degree of Bachelor of Science in Environmental Science.