Date of Award
Fall 12-2020
Degree Type
Masters Thesis
Degree Name
Master of Science (MS)
School
Ocean Science and Engineering
Committee Chair
Dr. Frank Hernandez
Committee Chair School
Ocean Science and Engineering
Committee Member 2
Dr. Kevin Dillon
Committee Member 2 School
Ocean Science and Engineering
Committee Member 3
Dr. Leila Hamdan
Committee Member 3 School
Ocean Science and Engineering
Committee Member 4
Dr. Robert Griffitt
Committee Member 4 School
Ocean Science and Engineering
Abstract
Microplastics are a concern in marine environments because they are highly durable, ubiquitous, and can be mistaken for food and ingested by small organisms. Pelagic Sargassum, an important habitat for larval and juvenile stages of many fish species, is found in large surface aggregations, and may provide complex structure in which microplastics become trapped. This could lead to greater risk of microplastic ingestion by fish early life stages associated with Sargassum habitats. To better understand the impacts of microplastics within Sargassum communities, this study examined 1) microplastic concentrations and ingestion by juvenile fishes associated with Sargassum; 2) the microbial communities associated with the Sargassum and microplastics; and 3) the influence of microplastic ingestion on the microbiomes of juvenile Gray Triggerfish. Neuston net samples were collected in 2017 and 2018 from open water and Sargassum habitats in the Gulf of Mexico to collect microplastics and fishes. Microplastic abundance was significantly higher in Sargassum habitats relative to open water habitats. Microplastics were identified in the stomach contents of many species of juvenile fishes with total microplastic frequency of occurrence ranging between 14.7-24.7%. Microplastics had a unique microbiome when compared to the surrounding environment. The microplastic microbiome was found to influence Gray Triggerfish gut microbiomes. The results from this project demonstrate that microplastics are being ingested by juvenile fishes in Sargassum and the unique microbiome of microplastics are influencing fish gut microbiomes.
Copyright
Lestrade, 2020
Recommended Citation
Lestrade, Olivia, "Microplastic Abundance, Distribution and Impacts on Sargassum-Associated Juvenile Fishes in the Gulf of Mexico" (2020). Master's Theses. 781.
https://aquila.usm.edu/masters_theses/781