Oyster aquaculture technology has been relatively static in an industry needing to grow to meet global protein demand and advance restoration. Oyster aquaculture is very labor intensive, often growing less than a half million oysters per acre depending on gear types and site location. Floating and off-bottom gear is typically positioned in the near-shore environment or in the upper few feet of the water column, limiting overall growth and increasing conflicts with land-owners and other stakeholders.
The patent-pending Solar Oyster Production System (SOPS) has been developed to take advantage of offshore space that is typically not used by other oyster aquaculture systems. The SOPS supports a series of cages in up to twenty feet of water and utilizes solar power to mechanically rotate the cage array through the water column and above the water, providing desiccation/air exposure and the opportunity for mechanized washing, which minimizes overall labor inputs. The rotation sequence can be programmed to meet the needs of the grower. The mooring system and robust design of the platform allows location of the SOPs in higher-energy environments, with integrated anti-poaching technology that allows units to be placed further offshore, potentially minimizing stakeholder conflict. SOPS can grow spat-on-shell oysters for restoration or from seed for market oysters. Approximately 200,000 oysters from seed can be grown on one 40’ x 25’ SOPS (see below). A large, 90’ x 67’ SOPS has been designed which would produce over 2,000,000 oysters annually.
In the Chesapeake Bay watershed, nitrogen and phosphorus credits for oysters harvested from aquaculture operations can be traded on the nutrient credit market. Use of the SOPS for 1 acre of high-density oyster aquaculture may remove nutrients equivalent to treating stormwater runoff from over 100 acres of impervious surface.
A SOPS prototype was launched in October 2021 and loaded with spat-on-shell oysters in coordination with the Chesapeake Bay Foundation. Growth was successful and the diploid oysters were deposited on a reef at the entrance to the Baltimore Harbor in early November 2022. Seed oysters are also being grown to gauge the effectiveness of the technology. Additional spat-on-shell will be grown in 2023 for restoration.