This Is AuburnElectronic Theses and Dissertations

Improving the (off)-bottom line: assessing the costs and benefits of different culture techniques on an Alabama commercial oyster farm




Hensey, Sarah

Type of Degree

Master's Thesis


Fisheries and Allied Aquacultures


Off-bottom oyster aquaculture is an expanding industry in the Gulf of Mexico region, however numerous challenges threaten the sustainability of regional farms. To offset the negative effects of these challenges, farmers often ask how they can reduce their production costs without compromising the quality of their oysters or their profitability. This study analyzed how four commonly used management techniques affected profitability through 1) a true accounting of production costs, 2) an analysis of whether buyers recognize differences in oyster quality produced by different methods, and 3) if the resulting differences affect their willingness to pay or purchase decisions. A commercial oyster farm using an adjustable longline system was installed in Grand Bay, AL where combinations of two brands of gear (Hexcyl or SEAPA), two tumbling frequencies (Monthly or Quarterly), two air-drying frequencies (Weekly or Daily), and two oyster seed ploidies (Diploid or Triploid) were tested. The resulting production costs and profits from each treatment combination were tracked and used to conduct investment analyses. In addition, oysters produced by each treatment were assessed quantitatively in the lab and qualitatively through a survey to gauge quality and buyer perception. Treatments including triploid oysters were assessed as having the highest quality, the best perception by buyers, and the most profitable business investments. More labor-intensive treatments did not appear to have an advantage when it came to quality or buyer perception, suggesting farmers can reduce their production costs by using quarterly tumbling and/or daily air-drying without penalty to profitability. Finally, brand of gear had few effects on quality, perception, or investment and therefore should be chosen based on personal circumstance or preference.