Date of Graduation
Fall 2024
Degree
Master of Science in Biology
Department
Biology
Committee Chair
Day Ligon
Abstract
This study investigated the population viability of the critically endangered Egyptian Tortoise (Testudo kleinmanni) across five populations in North Sinai, Egypt. The research aimed to assess demographic sensitivities, extinction risks, and the influence of environmental variables to guide conservation strategies. Using multistate mark-recapture models within a Bayesian framework, survival, transition, and recapture probabilities were estimated across life stages, integrating site-specific environmental data such as the Normalized Difference Vegetation Index (NDVI). The analysis revealed stark contrasts between populations, with three sites demonstrating high extinction risk due to lower juvenile survival and limited recruitment. In contrast, two populations exhibited demographic stability driven by higher survival rates and resilient recruitment. Population Viability Analysis identified female survival as the most critical factor for long-term stability, with elasticity analysis further emphasizing the importance of juvenile survival and transitions to adulthood. These findings underscore the ecological significance of habitat quality, with higher NDVI correlating positively with survival and productivity. Recommendations include habitat restoration, head-start programs for juveniles, and community-based conservation initiatives. This study highlights the urgent need for targeted, adaptive management to mitigate the ongoing threats of habitat degradation, climate variability, and human-induced pressures, offering an extensive framework for conserving this imperiled species.
Keywords
Egyptian Tortoise, population viability analysis, extinction risk, mark-recapture, Bayesian analysis, jags, sex ratio, habitat quality, conservation strategies, elasticity analysis
Subject Categories
Biodiversity | Biology | Ecology and Evolutionary Biology
Copyright
© Basem Ahmed Rabia Motwaly
Recommended Citation
Motwaly, Basem Ahmed Rabia, "Population Viability of Egyptian Tortoises: Analyzing Demographics Sensitivities and Extinction Risk in North Sinai" (2024). MSU Graduate Theses/Dissertations. 4016.
https://bearworks.missouristate.edu/theses/4016
Open Access