Date of Award
Spring 2026
Degree Type
Honors College Thesis
Academic Program
Marine Biology BS
Department
Marine Science
First Advisor
Michael J Andres Ph.D
Advisor Department
Coastal Sciences, Gulf Coast Research Laboratory
Abstract
The anadromous Gulf Sturgeon (Acipenser desotoi) is federally listed as “threatened” and is natal to seven rivers from Louisiana to Florida. Only one spawning reach for Gulf Sturgeon natal to the Pascagoula River has been verified via the collection of eggs and larvae; a reach of the lower Bouie River. This reach is anthropogenically modified by four gravel mining formations, hereafter referred to as pits. The greater depths associated with this area have prompted previous researchers to suggest that Gulf Sturgeon may over-summer in pit formations instead of migrating to downstream holding areas in the Pascagoula River after spawning. The objective of this study was to determine the environmental parameters associated with spawning movements in the Bouie River and compare thermal regimes in the pits to holding areas during summer. Adult Gulf Sturgeon were internally tagged with acoustic transmitters to monitor movement patterns from 2020 to 2025. Additionally, four vertical temperature moorings were deployed from February 2025–present to record vertical water temperature profiles. Generalized mixed linear models suggested that arrival to the Bouie River was associated with lower water discharge rates (m3.s-1), whereas departure was associated with increases in surface water temperature and daily change in water temperature. Sturgeon had varying occupancy rates in the pits, including some that remained until late-fall instead of migrating to downstream summer holding areas. Temperature monitoring of the pits revealed that stratification occurs beginning in May and persists through late September. Comparatively, temperatures in the middle and bottom waters of the pits were cooler than the downstream summer holding habitat. Paired use of temperature telemetry transmitters and environmental parameters suggests that sturgeon that over-summer in these habitats use the middle water column rather than occupying cooler, bottom waters. This finding suggests the potential for low dissolved oxygen in stratified bottom waters and warrants further research to determine the suitability of these pits for energetic refuge. This research identifies environmental stressors for spawning Pascagoula River sturgeon and may inform restoration of the lower Bouie River.
Copyright
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Recommended Citation
St. Germain, Oliviia, "Evaluating the Environmental Parameters Impacting Spawning Movement of Gulf Sturgeon (Acipenser desotoi) in the Bouie River System." (2026). Honors Theses. 1107.
https://aquila.usm.edu/honors_theses/1107