Date of Award

5-2026

Degree Type

Masters Thesis

Degree Name

Master of Science (MS)

School

Ocean Science and Engineering

Committee Chair

Michael Andres

Committee Chair School

Ocean Science and Engineering

Committee Member 2

Kim de Mutsert

Committee Member 2 School

Ocean Science and Engineering

Committee Member 3

Chet Rakocinski

Committee Member 3 School

Ocean Science and Engineering

Abstract

Black Drum (Pogonias cromis) and Sheepshead (Archosargus probatocephalus) are ecologically and economically important estuarine fishes throughout the northern Gulf of Mexico. Despite their value, little is known about their spatial ecology, including patterns of residency, movement, and connectivity within northern Gulf estuarine systems. This study is the first to quantity subsystem-level use of these species in Mississippi Sound and assess the extent of individual variability in movement, connectivity, and reproductive-related behavior. Fish were captured across multiple subsystems and tagged with acoustic transmitters to monitor movements from 2021-2025. Movement patterns were analyzed using residency indices, network metrics, and environmental covariates, while Sheepshead maturity was inferred using size-based logistic regressions. Results indicated generally strong site fidelity, but with seasonal reductions in residency during known spawning months, consistent with partial spawning migrations. Black Drum tagged in Pascagoula River Estuary exhibited broader movements and higher inter-subsystem transition frequencies compared to St. Louis Bay-tagged individuals, highlighting spatial variability in connectivity. Network analyses identified Pascagoula River Estuary and St. Louis Bay as key components of the regional estuarine network, with certain subsystems acting as movement hubs. Environmental factors influenced subsystem departure probability, but individual-level variability was a stronger driver of movement. Collectively, these results demonstrate that Black Drum and Sheepshead exhibit diverse movement strategies and spatially variable survival within a relatively small estuarine system. These findings provide critical information for population connectivity assessments and support the development of targeted management strategies to conserve these important species in the northern Gulf of Mexico.

Available for download on Thursday, May 18, 2028

Share

COinS