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of nitrogen per year from the river. This would be i Report of the 10% of the 5000 kilograms of nitrogen per year reduc- Shellfish Department tion of the nitrogen load in the Mashpee River targeted in the Massachusetts Estuaries Project report on Popponesset Bay (Linked Watershed-Embayment To the Honorable Board of Selectmen Model to Determine Critical Nitrogen Loading t and the Citizens of the Town of Mashpee Thresholds for Popponesset Bay, Mashpee and Barnstable Massachusetts, 2004). The Mashpee Shellfish Department brought the concept of shellfish Enforcement, resource management, shellfish P g P propagation and water quality work resulted in an aquaculture for nitrogen removal to the US abundance of quahogs, good sets of soft-shell clams, Environmental Protection Agency pilot project for and a successfully re-established scallop fishery. The nitrogen management of the Popponesset Bay system that we are working on with state and local agencies. Mashpee River South of Buccaneer Way, Shoestring Bay South of Simon's Narrows Road, and upper Also in 2004, a new experimental soft-shell clam Popponesset Bay opened for shellfishing in January, p February and March. Those areas are closed at other propagation project was started. The Barnstable times of the year because of high fecal coliform bacte- County/DMF donated about 200,000 small soft-shell ria counts, and open in the colder months after the clam seed. These were planted in sand and covered temperatures drop low enough to kill the bacteria. In with nets for protection from predators. The success- December 2004, temperatures in the Mashpee River ful growth demonstrated that soft-shell clam propaga- dropped as low as 30 degrees Fahrenheit. tion is possible in Mashpee. We grew two million quahog seed, and one mil- The propagation program is critical for shellfish lion scallop seed in the propagation program. The such as scallops. Before scallop seeding was added to very small (1 mm) quahog seed was provided by the propagation program several years ago, scallops Barnstable County and the Massachusetts Division of had become so scarce that people came in with just a Marine Fisheries (DMF) at no cost to the Town. The few or no scallops on opening day, and that was it for very small scallop seed was purchased with funds the season. We have re-established a scallop fishery from Mashpee shellfish permit fees. After growing in by releasing large seed grown in our propagation pro- our upweller tanks and trays to larger sizes, the seed gram. Falmouth also releases seed scallops on their was planted in the fall. The seed was worth about side of Waquoit Bay. We need to seed every year to $100,000 when planted (if we had purchased the seed maintain the fishery, because the scallop populations at that size). do not sustain themselves in the wild. From October through December 2004, about 50 bushels of scallops In 2004, we started a new oyster propagation were harvested in Waquoit Bay. project in the Mashpee River. The objectives are to restore the oyster fishery and mitigate eutrophication The propagation program also makes other shell- by removing algae and nitrogen. Oysters feed by fil- fish productive in areas that were previously unpro- tering algae that grow on the nitrogen and other nutri- ductive. The family shellfishing area in Popponesset Bay lacked shellfish prior to the start of quahog seed- ents. Most of the nitrogen enters the estuary in fresh t water. Oysters grow well in the low salinity areas of ing in the year 2000. Natural spawns could not set the river where the nitrogen concentrations are high, there because they were swept away by strong tidal and can remove nitrogen to reduce the impacts down- currents. Quahog seed from the propagation program is successful because it is grown to a largee size beforesCream. When people harvest the oysters, the will be lantin so that it is not swept away. removing nitrogen and helping to reduce the impacts p g p y on the estuary. From very small spat (1 mm) set on pieces of shell that we got from the hatchery in June, The members of AmeriCorps Cape Cod put in i more than 150,000 oyster seed grew to sizes from one many hours working on the propagation program. inch to just under three inches by the fall. Our water Kate Basham and Megan Hartmann,AmeriCorps biol- quality monitoring showed that this fast growth was ogists assigned to the Shellfish Dept, put in many often optimal more hours working on the propagation and water the result of warm temperatures, and o levels of the some of the best species of algae for oys- quality programs. ter food. The project was funded by Barnstable County and the DMF, and is funded again for next The massive bed of seaweed is still growing on year. We estimate that intensive shellfish aquaculture the bottom of Waquoit Bay. It did not float to the sur- face in 2004 as happened in June 2003 when an unusu- has the potential to create large shellfish harvests resulting in the removal of as much as 500 kilograms ally long cold, cloudy spring was followed by warm sunny weather that caused rapid growth and the result- 135