Date of Award
Spring 5-7-2026
Document Type
Thesis
Degree Name
Bachelor of Science (BS)
Department
Biology
College
Honors College
First Advisor
Michelle M. Barthet
Abstract/Description
Macroalgae act as important refuges for planktonic larval forms of many creatures in an otherwise hostile or barren environment, they also serve as primary producers in many food webs and sediment stabilizers in dynamic environments making them critical foundational species in many marine ecosystems. This project adds to the collective knowledge of macroalgae along the SC coast that may impact human and ecosystem health. We used DNA barcoding techniques alongside morphological assessment including microscopic analysis, to identify species of marine macroalgae collected at various jetties, docks, and piers across the Grand Strand region of South Carolina. Five DNA barcoding primer sets were tested to determine the ideal set for genus and species identification of macroalgae. Amplified products were cleaned of residual PCR components, sequenced, and analyzed for species identification using the BLAST algorithm in GenBank. We determined that primers targeting the mitochondrial tufa and p23 gene regions were best for amplification and species determination of most macroalgal groups. Primers targeting the ITS gene were least effective for amplification and species identification efforts. We determined that 30% of collected samples belong to the phyla Chlorophyta, 49% to Rhodophyta, and 21% to Phaeophyta. Sequences in the genus Ulva and Codium were most successful in amplification and species discernment. Larger, more intricate algae were found in tidally influenced waters sheltered from harsh wave action. Highest species diversity and taxa richness were found at Huntington Beach State Park Jetty. Non-native and potentially invasive species such as Codium fragile and Ulva ohnoi were discovered along the Grand Strand coast. These invasive species will be compared to local Herbaria records to determine if their presence in the region is novel or previously established. This survey acts as a revival to our knowledge of local macroalgal species and the preservation of that knowledge through herbarium curation.
Recommended Citation
Long, Taylor R., "Surveying the Grand Strand: Using Morphology and Genetics to Document Local Macroalgal Biodiversity" (2026). Honors Theses. 523.
https://digitalcommons.coastal.edu/honors-theses/523