Ovarian Biomarkers of Two Wild Green Sea Turtle (Chelonia mydas) Populations Across the Nesting Season

Author

• Piper Jamison Johnson, The University of Texas Rio Grande Valley

Date of Award

7-1-2026

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Ocean, Coastal, and Earth Sciences

First Advisor

Roldán Valverde

Second Advisor

Md Saydur Rahman

Third Advisor

Richard Kline

Abstract

Vitellogenesis is an essential process in the reproductive cycle of sea turtles. Previous studies have suggested species-level differences in ovarian biomarkers of reproduction during limited periods of the nesting season in these species; however, population-level differences have not yet been documented. Plasma concentrations of vitellogenin (VTG) and testosterone (T) were measured in two wild green sea turtle (Chelonia mydas) populations from Tortuguero, Costa Rica and Colola Beach, Mexico, across the entire respective nesting season. Concentrations of VTG and T were found to differ throughout the nesting season. Concentrations of T displayed seasonal differences in Tortuguero, but not VTG. Nesting green sea turtles from Tortuguero displayed higher overall concentrations of VTG, likely necessary to support larger ovaries, but lower overall concentrations of T compared to those in Colola. The results of this study suggest population-level differences in reproductive biomarkers of green sea turtles, likely linked to observed differences in life-history traits.

Comments

Copyright 2026 Piper Jamison Johnson. All Rights Reserved. https://proquest.com/docview/3409015446

Recommended Citation

Johnson, P. J. (2026). Ovarian Biomarkers of Two Wild Green Sea Turtle (Chelonia mydas) Populations Across the Nesting Season [Master's thesis, The University of Texas Rio Grande Valley]. ScholarWorks @ UTRGV. https://scholarworks.utrgv.edu/etd/2009