Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)


Ocean, Coastal, and Earth Sciences

First Advisor

Dr. Carlos Cintra-Buenrostro

Second Advisor

Dr. Alejandro Fierro-Cabo

Third Advisor

Dr. Richard Kline


Estuaries act as nurseries for many important fishes, including predators like Red Drum (Sciaenops ocellatus). Using gut content and stable isotope analyses to better understand juvenile S. ocellatus’ diet and role within the trophic web, a full year of data was collected on a quarterly basis to illustrate a change in diet based on resource availability at two study sites and for two non-overlapping S. ocellatus sizes. Panopeidae and Penaeidae were the most abundant prey items found in S. ocellatus stomachs for both sizes, sites, and four quarters representing over 50% of the diet. Stable isotope analyses from 80 fish show that S. ocellatus are feeding in very similar trophic levels but nonetheless there are significant differences for all quarters in δ15N between sites and δ13C between sizes, sites, and quarters. Differences may be linked to changing resources throughout the year, site composition differences, and seasonal changes in productivity.


Copyright 2022 Elizabeth Mogus Garcia. All Rights Reserved.