Mathematical Modeling of Green Sea Turtle Population Dynamics Under Environmental and Thermal Constraints

Abstract

Global warming and deteriorating environmental conditions have raised concerns about the persistence of green sea turtle populations, whose reproduction is governed by temperature-dependent sex determination. This study employs math- ematical modeling to investigate these ecological challenges. Building on our previ- ous models of green sea turtle population dynamics, we develop a sex-structured and stage-structured life history model that integrates temperature-dependent sex deter- mination and ecological viability, offering a mechanistic framework for understanding green sea turtle population dynamics under climate and environmental stress. Our findings reveal that population dynamics are governed by an Allee-adjusted repro- ductive number, which accounts for both thermal and environmental influences. Ad- ditionally, we conduct a global stability analysis of the collapsed equilibrium using the singular perturbation approach, offering insights into long-term population viability. While additional parameter validation is necessary for definitive conclusions, our re- sults illustrate how climate change and deteriorating environmental conditions shape the long-term viability of green sea turtle populations.

Keywords

Temperature-dependent sex determination / green sea turtle / sex-structured and sta-ge-structured / Allee effects / population collapse / bi-stability

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