Document Type

Honors Thesis


An infectious turtle disease called bunyavirus that can lead to hemorrhagic fevers was emerging so the Texas Parks and Wildlife Department monitored turtle populations through the use of capture recapture studies in various lakes to determine if the turtle population increase, decreased, or remained stable, which is a good indicator of population demographics throughout the years to see if the turtles were being harmed by the virus, various parasites, hunting, etc. This focused on the population of four turtle species, including Apalone spinifera (spiny softshell), Chelydra serpentina (common snapping turtle), Psudemys spp. (river cooter), and Trachemys scripta (pond slider) in French Lake, at Fort Worth, Texas, USA. The turtles were captured, tagged, and recorded over a course of ten trapping periods in three years. The population data for each species was analyzed through the statistical program MARK. For Apalone spinifera, Chelydra serpentina, and Psudemys spp., the population estimate was 20.000, 11.000, and 5.000 respectively with no upper and lower bounds due to low capture rates. For Trachemys scripta, the populationestimate was 278.375, with upper and lower bounds of 321.452 and 249.099, respectively. The population estimates are essential in evaluating the overall lake health and keeping the ecological food web in check. Because T. scripta made up the majority of the turtle population and was the primary indicator of turtle population health in French Lake with a large amount of recaptures over the years, this demonstrates that the turtle population is stable and is not heavily impacted by the presence of the bunyavirus in regards to this ecosystem at French Lake.

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