THE EXPANSION OF A NATIVE GENERALIST SPECIES FOLLOWING COMPETITIVE RELEASE AND HABITAT DEGRADATION

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)