Year
2024
Season
Fall
Paper Type
Master's Thesis
College
College of Arts and Sciences
Degree Name
Master of Science in Biology (MS)
Department
Biology
NACO controlled Corporate Body
University of North Florida. Department of Biology
First Advisor
Dr. Jim Gelsleichter
Second Advisor
Dr. Eric Johnson
Third Advisor
Dr. Demian Chapman
Abstract
Recently, there has been increasing use of baited remote underwater video (BRUV) surveys for assessing shark and fish populations in marine ecosystems. This approach can be useful because it may provide a non-destructive, non-extractive, and cost-effective alternative to traditional fishing-based methods. However, to date, most studies using BRUVs have focused on their use in high-visibility ecosystems, such as tropical reefs. Furthermore, few studies have compared results from BRUV surveys with those obtained using traditional methods to evaluate the efficacy of this approach. Therefore, the goal of this study was to evaluate the effectiveness of using BRUV surveys to assess shark and fish populations in low-visibility ecosystems. This goal was addressed by conducting BRUVs and bottom longline surveys in the Tolomato River, a northeast Florida estuary that has been shown to serve as a communal nursery habitat for juveniles from multiple coastal shark species including the sandbar (Carcharhinus plumbeus) and the scalloped hammerhead (Sphyrna lewini). Surveys were compared using metrics of both abundance and diversity. Results of this study found that BRUV and longline surveys sampled different portions of the community and BRUV surveys were able to detect a greater number of species, including some that are not sampled using a longline survey in this system. However, longline surveys produced greater sample sizes, greater abundance estimates, and provided more information on shark populations, compared to BRUV surveys. While BRUV surveys did not provide similar data to longline surveys, especially regarding abundance estimates, they may work as a useful tool to provide insight into community ecology. The addition of a clear liquid optical chamber (CLOC) to the BRUV design was also briefly investigated, suggesting that clarity can potentially be improved in low-visibility estuarine systems.
Suggested Citation
Worthington, Sarah, "Evaluating the use of baited remote underwater video (BRUV) in assessing shark and fish populations in a low visibility estuarine system, the Tolomato River, FL, USA" (2024). UNF Graduate Theses and Dissertations. 1314.
https://digitalcommons.unf.edu/etd/1314
