Location: National Cold Water Marine Aquaculture Center
Project Number: 8030-31000-005-060-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jun 10, 2024
End Date: Jun 9, 2025
Objective:
To conduct progeny tests of USDA ARS germplasm intended for genetic improvement as part of the northeast eastern oyster breeding program.
Approach:
The USDA-ARS National Cold Water Marine Aquaculture Center will spawn wild oysters collected from sites throughout New England to create a genetically diverse base population that will serve as generation zero of a northeast regional breeding program. The base population will consist of 100 - 120 single pair crosses (families) combined into 25 – 30 rearing groups (4 families per group). ARS will rear the spat in a land-based nursery system until they reach ~ 4 mm in size. Then they will be tested for disease-free certification, packaged in labeled mesh spat bags (1.5 to 4 mm mesh) and transferred to the cooperator’s farm for deployment.
The cooperator will receive approximately 3000 seed oysters per rearing group (up to 90,000 seed total) in mid-June to early July. This timing coincides with the on-farm husbandry schedule and will maximize early growth, minimize disease-related juvenile mortality, and reduce overwintering losses. The cooperator will maintain ARS seed oysters at their farm lease in their gear for up to 24 months using routine on-farm practices with some modification. Modifications include always keeping ARS-provided group labels with the seed, maintaining each group in replicated gear (3 bags per group; ~ 100 bags total), and keeping replicated groups separate (no mixing bags). No size grading of ARS seed will be performed during the grow-out period to allow for an unbiased assessment of group-specific growth traits that will inform selection on future generations.
Concurrent with seed deployment, ARS will install a solar-charged cellular data buoy equipped with water quality instrumentation (temperature, conductivity, dissolved oxygen, and total algae sensors) to characterize environmental conditions on the farm. The cooperator and ARS will communicate regularly to determine the appropriate schedule for replication, transfer of seed to larger gear, and bag thinning to maintain healthy and roughly equal densities across replicated groups. ARS will coordinate access to the experimental material and farm gear pertaining to the project with the cooperator for thinning and performance evaluation. Performance will be evaluated at 12- and 18-months post-fertilization. At each time point, ARS will assess survival and measure shell height, shell width, shell depth, total weight, and meat weight of 30 oysters per bag. At the end of the evaluation period, the cooperator will maintain a subset of the experimental material for an additional 4-6 months. This subset will serve as broodstock for the next generation of the breeding program.
In New England, it takes cultured oysters 18 months to reach market size. Therefore, this agreement is intended to cover two overlapping generations of our base-breeding population spanning 36 months. Generation 1 will begin in the spring of 2024 and generation 2 in the spring of 2025. At the completion of the generation 2 grow-out period, our base breeding population will be closed, and selection will commence.
