Date of Award


Document Type


Degree Name

Master of Science in Coastal Marine and Wetland Studies


Coastal and Marine Systems Science


College of Science

First Advisor

Robert F. Young

Second Advisor

Erin J. Burge

Third Advisor

John J. Hutchens, Jr.

Additional Advisors

Patricia Rosel


Environmental DNA (eDNA) analysis is a non-invasive monitoring technique that can detect and potentially monitor elusive marine mammals. To date, the majority of eDNA studies have been performed in freshwater environments, partially due to methodological challenges posed by higher salinities and increased dilution effects of large water masses in marine environments. The objective of this study was to design and optimize species-specific oligonucleotide PCR primers to accurately detect and quantify common bottlenose dolphin (Tursiops truncatus) eDNA collected from the marine environment and to evaluate potential trends between eDNA concentration and dolphin abundance and seasonality. Primer pairs were designed to target 159 and 92 base pair (bp) fragments of the mitochondrial DNA (mtDNA) control region and Cytochrome b gene (cytb), respectively. Common bottlenose dolphin eDNA was analyzed from water samples collected in two estuarine salt marshes (North Inlet and Cape Romain) and the coastal ocean in South Carolina, USA. A total of 176 water samples were analyzed, including 132 from predetermined survey locations and 44 collected directly in the wake of dolphins. Relationships were observed between (1) location and number of positive eDNA detections per survey, (2) mean concentration of positive eDNA detections and dolphin sightings per survey, and (3) dolphin group size and the concentration of eDNA in water samples collected in the group’s wake in salt marsh systems. Results provide evidence for the utility of eDNA techniques in examining the presence, relative abundance, and distribution of common bottlenose dolphins. This study highlights the challenges and implications of eDNA detection in the marine environment.