As of June 2015, the project has been completed. Details for each item are presented below.

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1 TO: Gerald C. Potamis, Falmouth Wastewater Superintendent and Taree McIntyre, CCEDC FROM: Sia Karplus, Water Quality Technical Consultant DATE: June 22, 2015 RE: Cape Cod Economic Development Council (CCEDC) Grant FINAL REPORT On June 25, 2014, the Town of Falmouth received a $29,000 grant contract from the CCEDC for expenses related to the second year of Falmouth s Little Pond Shellfish Demonstration Project (Shellfish Demonstration). This grant money was used to cover a portion of the expenses associated with three budget items: (1) purchase of 1.5 million oyster seed (2) labor expenses related to growing and relaying seed and (3) testing required by the state Division of Marine Fisheries (DMF) for seed relay into other waterbodies for grow-out. The purpose of this Demonstration is to: Quantify the nutrient-removal benefits of oyster aquaculture for regulatory compliance Optimize a plan for shellfish aquaculture implementation Solidify the inter-departmental and inter-agency collaborations that are necessary for this project to endure. Relay 1.5 million oyster seed that were purchased in 2014 into commercial and recreational shellfishing areas so that the oysters will be harvested. Relay and Depuration The oysters are not permitted to reach legal size (3 inches) in Little Pond, because it has waters classified as prohibited by the MA Division of Marine Fisheries. Shellfish grown in prohibited waters require one or more spawning seasons and a minimum of 6 months of natural depuration (or cleaning) before harvest. After 6 months, the shellfish are considered safe for harvest and consumption. To meet this requirement all oysters are moved to other waterbodies for natural cleaning. The approximate size at relay is between inch, well short of the legal 3 inches. Testing of seed for relay must occur twice: once early in the season when seed is moved from the upweller in Falmouth Harbor to Little Pond, and then at the end of the growing season when the shellfish are moved from Little Pond to relay locations. All testing occurred for the 2014 seed, and relays proceeded as planned because no disease was found. As of June 2015, the project has been completed. Details for each item are presented below. Quantifying the nutrient-removal benefits of oyster aquaculture for regulatory compliance Over the 2014 growing season, water quality monitoring was conducted by the UMass Dartmouth School for Marine Science and Technology (SMAST). Results were analyzed and reported in the spring of 2015 to the Falmouth Water Quality Management Committee and Falmouth Conservation Commission. Overall findings demonstrate an increase in water clarity, and a decrease in chlorophyll a and Total Nitrogen within the oyster growing area. This localized improvement was also seen in 2013 data. The water quality monitoring report is attached. In addition, the size classes grown during the 2014 season were quantified prior to relay. Different size classes of oysters were then sent to the Boston University Stable Isotope Laboratory for analysis of the nitrogen content in the shell and soft tissue. These results were provided to the town in early January, 2015, and confirmed that the total mass of nitrogen taken up by oysters is comparable to the results published by Barnstable County Cooperative Extension. Together, the water quality and oyster nitrogen data will allow for some quantification of nitrogen-removal from the 2014 growing season. Town of Falmouth CCEDC Grant Final Report Page 1 of 6

2 In cooperation with the Center for Coastal Studies, an analysis of shellfish uptake of certain Contaminants of Emerging Concern was also accomplished. These results were also reported in early Of particular note is that in 2014, over 300,000 oysters were relayed into Quissett Harbor. Because the total mass of nitrogen-removal that is required to achieve TMDL-compliance is relatively small in this waterbody (~266 kg/year), it is possible that water quality improvements at the Sentinel Station may be detected next season due to the oysters. This data collection is planned as part of the third year of the Shellfish Demonstration. Figure 1. Spatial Layout of Water Quality Sampling Stations Town of Falmouth CCEDC Grant Final Report Page 2 of 6

3 Optimizing a plan for shellfish aquaculture implementation Based on 2014 efforts, an Operations Manual is being developed that will include the following sections: 1. Upweller a. Start-up b. Cleaning schedule c. Growth rate of seed d. Timing of first test - how long after seed is installed e. Expected timing of relay out of upweller 2. Relay into Little Pond a. Graphic on steps for building a bag b. Number of bags for 1 million seed at a density of 1L/bag c. Schematic map of bags/rafts d. Daily/weekly maintenance schedule with list of tasks e. Standard Operating Procedures for how to accomplish schedule/tasks 3. Testing Schedule: a. Spreadsheet/Gantt chart with list of tests, timing of tests (weeks from installation) where to send/contact info b. List of tests and where to send for nitrogen content of shell/soft tissue (both for seed in LP and in relay areas) c. Population survey for relayed seed prior to harvest 4. Relay out of LP (Little Pond) a. Paragraph on DMF permit approval process, including a copy of the forms b. Schedule (when to start planning, when to start moving, how long it takes) c. Estimate of how long it takes to relay 1 M oysters 5. Tips for Success a. Anything you would want someone to know about how to get the job done successfully Town of Falmouth CCEDC Grant Final Report Page 3 of 6

4 Solidify the inter-departmental and inter-agency collaborations that are necessary for this project to endure This manual is currently being compiled by the Little Pond Project Manager and will be completed in August, A key milestone in the Shellfish Demonstration is the incorporation of this project into the Falmouth Division of Environmental Services propagation program. The full-time Division of Marine and Environmental Services (DMES) Fisheries Technician is working closely with the Little Pond Project Manager to implement year 3 of the shellfish demonstration. Falmouth DMES also funded half of the budget for year 3 as well. Little Pond has proven to be an excellent nursery for growing oysters for one season, providing shellfish that are successfully harvested after relay and depuration. Working closely with the Division of Marine Fisheries has helped transition the demonstration into the propagation budget of this department and has created a deeper understanding of the logistics of this program, thus institutionalizing this effort. Relaying 2 million oysters into commercial and recreational shellfishing areas so that the oysters will be harvested A key success of this Shellfish Demonstration is that approximately 1.5 million shellfish were grown successfully in the 2014 growing season, and relayed into commercial and recreational shellfish harvest areas in West Falmouth Harbor, Quissett Harbor and Green Pond. In the fall of 2015, these oysters will be available for harvest. A population study was conducted in West Falmouth Harbor prior to opening the area to harvest of 2013 and oyster survival was over 80%. The oysters harvested were highly desirable both commercially as well as recreationally. Based on the success of the first year s harvest, the harvest from the 2014 effort that was supported by this grant is estimated at over 1 million oysters. The economic value of this harvest in October 2015 could be as high as $500,000. Figure 2. Little Pond Growing Area Town of Falmouth CCEDC Grant Final Report Page 4 of 6

5 Figure 3. Relay Location - Green Pond Figure 4. Relay Location Quissett Harbor Town of Falmouth CCEDC Grant Final Report Page 5 of 6

6 Figure 5. Relay Sites West Falmouth Harbor Town of Falmouth CCEDC Grant Final Report Page 6 of 6