WWW.WAS.ORG • WORLD AQUACULTURE • DECEMBER 2017 59 (CONTINUED ON PAGE 60) Oyster Gardening in Delaware Oyster gardening is the nursery culture of small, hatchery-produced oysters to a larger juvenile size. Diseaseresistant Eastern oyster Crassostrea virginica larvae were obtained from Rutgers University’s Haskin Shellfish Laboratory. Remote setting was used to settle the larvae on cultch bags, hanging baskets or trays (Figs. 2-5). The 5-10 mm spat-on-shell (Fig. 6) was transferred to baskets placed in Taylor floats that were tied to docks owned by volunteers (Fig. 7). Gardeners kept oyster spat clean and protected from predators. Oysters held off bottom have better conditions for growth — increased water flow and greater access to particulate food — so they reach a planting size of 2.5-5 cm much more rapidly than oysters on the bottom (Ewart 2008). The larger size is preferred for stocking artificial oyster reefs and other shellfish restoration projects because they have better survival rates. Oysters grown for re-introduction to the ecosystem are placed in strategic locations, contributing to restoration and enhancement of natural oyster populations of the Inland Bays. The Delaware Oyster Gardening Program, initiated during summer 2003, is a cooperative effort implemented by the Delaware Coastal areas are characterized by concentrated natural and economic resources, population and economic development. The US coasts are home to more than half of the nation’s population and are also the most developed areas in the country (NOS 2011). Humans have considerable impact on US coastal ecosystems and restoration is needed to improve environmental quality. Current rates of resource depletion and environmental degradation are not sustainable (Thanawala 2001). The Inland Bays of Delaware (Fig. 1) are associated with the mouths of the Rehoboth, Indian, and the Little Assawoman Rivers and have an area of about 83 km2 (Martin 1996). Two critical environmental issues have been identified as threats to the Delaware’s Inland Bays — eutrophication, caused by high levels of nitrogen and phosphorus, and habitat loss (EPA 2011). Shellfish culture can have positive effects on the environment, promote biodiversity and enhance habitat quality. Oyster culture has the potential to reduce pressure on natural overexploited populations and to generate income for coastal communities (Buitrago 2005). For the past fourteen years, oyster gardening has been a part of the restoration of the Inland Bays of Delaware. Gauging Benefits of Oyster Garden Restoration in Delaware Gulnihal Ozbay and Amy Cannon FIGURE 1. Delaware Inland Bays with oyster gardening sites. FIGURE 2. Volunteer oyster gardener prepares tray for remote setting. FIGURE 3. Shells in trays in remote setting tank.
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