Date of Award

Spring 5-8-2021

Document Type


Degree Name

Bachelor of Science (BS)


Marine Science


College of Science

First Advisor

Juliana M. Harding


Eastern oysters (Crassostrea virginica) provide ecological services in many estuaries. Individual physiological rates and scope for growth are influenced by ambient temperature, salinity, and food conditions. The seasonality of shell growth signature deposition in North Inlet estuary, South Carolina oysters was quantitatively evaluated in shells collected at known intervals from 2012 to 2021. A cross-section along the growth axis of each left valve was used to identify external growth signatures and measure the most recent terminal growth increment (TGI, mm), the distance from the previous external growth signature to the terminal edge. TGIs and increments standardized to shell length (to correct for potential effects of ontogeny) varied inversely with temperature but were independent of salinity. Average TGI (5.08 ±1.23 mm) and standardized TGI (0.073 ±0.023) were greatest when temperatures were falling from 26 to 18°C in September to mid-October, and lowest (1.42 ±0.94 mm; 0.018 ±0.012) when temperatures exceeded 26°C (late June to August). Average TGIs and standardized TGIs from winter (8 to 12°C, late November to early February) and early fall (26 to 18°C, September to mid-October) were significantly greater than those collected in other seasons. North Inlet oyster external shell growth reflects the ambient temperature at collection demonstrating that shell growth follows an annual seasonal cycle.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.

Available for download on Friday, December 31, 2027