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To quantify the effects of seasonal harvests on ploidy type, several spawns using tetraploid oysters held from the spring 2016 spawn were attempted in the fall at a participating commercial hatchery; however, viable gametes were not obtained. Since availability of triploid seed was limited, it was decided to purchase single-set seed with project funds from the Louisiana Sea Grant oyster hatchery and Auburn University shellfish hatchery. Disease certifications and ploidy verification required by the Department of Agriculture and Consumer Services for out-of-state oyster seed were obtained. These stocks were combined. A similar number of diploid seed was obtained from a

Six months after seed oysters (average 25 mm in shell height) were stocked into 14 mm mesh Vexar bags (October 2016), they were harvested in April 2017 (12 months from spawn). Replicated field trials were conducted at the UF experimental lease within the Dog Island Aquaculture Use Area off Cedar Key to document the effects of ploidy (diploid versus triploid), stocking density (125, 150, 175 oysters/bag), and float design (square versus bullet) on oyster production. To determine growth, a sample of 35 oysters from each of the 42 bags (six replicate bags per treatment) were measured for shell height, length,

Ten growers in four west coast counties (Charlotte, Franklin, Levy, and Wakulla) participating in this project received oyster seed (2500 of each ploidy type, 20-22 mm in shell height) during July 2016 to grow on their leases. These growers used a variety of culture methods, which allowed for evaluation of site and gear interaction on ploidy type. To document production performance and assess health of diploid (2N) and triploid (3N) oysters under commercial conditions, oysters from three replicate bags (four baskets if using the adjustable longline system) for each ploidy type were provided to the UF project team at harvest.

A similar number of oysters provided to project participants were also cultured at the UF experimental lease off Cedar Key so that growth and survival could be documented bimonthly during growout. Oysters (ave 26 mm shell length) were stocked in 14 mm mesh bags in October (see previous post) and sampled in December 2016 and, again, in February 2017. Three bags from each of the density and ploidy combinations, a total of 18 bags, were sampled each period. These bags were supported with square floats; in addition, three bags supported with bullet floats were also sampled. Different replicate bags were

Another component of the Oyster Culture Demonstration Project is to document economic costs and benefits associated with diploid versus triploid oyster production along the west coast of Florida. To help collect cost and sales data, UF economists and a graduate student have partnered with oyster farmers to provide “real-world” estimates allowing for a better understanding of production methods, operational costs, and farm-gate revenues associated with growing the two ploidy types. Findings will be transferred into a financial spreadsheet that the user can adjust based on their unique farming and investment situation (e.g., farm size, # seed planted). To make this