Harwich Shellfish Lab and
Cooperative Shellfish Project

  • Phytoplankton Montioring Program
  • Shellfish Lab Highlights
  • Shellfish Lab Production 1994-2004
  • Shellfish Lab Seed Survival % and average size (mm)
  • Shellfish Visitors
  • Shellfish Aquaculture Glossary

    PROJECT SUMMARY

    2002 Summer Interns at the Harwich Shellfish Lab carry on a Program of Environmental Tradition to reseed the beds and Give our Clams a "Fighting Chance"

    In 1997 the Town of Harwich modified and expanded its existing shellfish propagation facility at Wychmere Harbor. This involved rebuilding and adding fiberglass tanks and silos, increasing pumping capacity and replacing delivery lines and valves. The indoor shellfish lab now has a rearing capacity of 6 x 106 hard clams




    Petri dish showing healthy 3 mm size mercenaria notata being reared in Harwich Upweller system.Press picture for interim report.
    and continues to be the largest municipal upwelling system in the State. There is now a total of 60 - 18" silos on line in the system. The Town now seeks to supplement its propagation budget to test the full capacity of the system using locally spawned clams. Harwich will maximize the capacity by sharing the systems early season growing space with the Brewster Natural Resources Department. Harwich will further its collaborative effort with Brewster by providing dock space in 1998 at Saquatucket Marina for an innovative floating upwelling barge. This cooperative effort will dramatically increase the supply of hard shell clams to the two communities. At the same time, the HNRD will develop a school link with the Harwich School Department to expose students to the current technology. In 1998, a $12,000 grant from the Division of Marine Fisheries and The Cape Cod Chamber of Commerce heavily supplements the Town of Harwich shellfish propagation budget for purchasing the post set juvenile seed

    Identification of Opportunities

    The Town of Harwich Natural Resources Department (HNRD) and the Town of Brewster Natural Resources Department (BNRD) seek to continue a cooperative arrangement which began in 1997. This arrangement optimized the benefits of shellfish propagation by both towns. The HNRD has since 1995 successfully operated a shellfish propagation facility at Wychmere Town Pier. Tiny clams purchased at 500 microns were reared to 12 to 20 mm. In November the animals were moved to the protection of bottom beds while the largest seed were broadcast into the wild areas. This has been an innovative and economically valuable operation, showing positive results and great promise for expansion. That expansion came in 1997 with the assistance of moneys received through the Municipal Shellfish Propagation Grant Program which partially funded a grant proposal from HNRD. The results of this ongoing effort are clearly found within the family permit and the commercial harvest of quahogs in Harwich. This effort is generating significant economic benefit while keeping the fishery viable. Natural Resources Director Tom leach and Heinz Proft, Assistant to the Director will operate manage the continuing project. Mr.Proft has a myriad of experience in fisheries culture as a reasearch assistant at Woods Hole.



    Harwich students learn about invertebrates through husbandry and research. Clean tanks and silos are essential for controling competing organisms, tunicates as sea squirts and filamentous algae.Press picture to read about tunicates.

    The BNRD has made available broad shellfish flats (formerly productive bottom) where quahogs generate impressive growth as a support and grow out area prior to release back in Harwich waters. It also purchases seed to augment the its wild fishery. The two towns wish to continue to advantage their collaborative in providing a regional shellfish propagation effort for the benefit of both towns and the surrounding region. Harwich seeks to stabilize its laboratory seed shellfish production and nursery operation while Brewster wishes to follow through a part of what was the Harwich plan in 1997. That idea was to augment and stabilize the production of seed available by developing not a tidal upweller but a pump driven upweller raft. Brewster lacks a quality site for a nursery operation as the one in Harwich. The grant holders of Brewster can realize significant savings on their purchase of juvenile stock by purchasing the smallest size available and utilizing the upweller technology. Due to the small tidal prism, Harwich lacks sufficient intertidal bottom area suitable for interim grow-out of post nursery stock. On the other hand, based upon 1997 results, it would be advantageous for the HNRD to buy seed at a slightly larger 750 microns, but lacks sufficient resources to purchase six million seed. The 1997 effort was the first ever of resource "sharing" in attempt to optimize the total number of juvenile hard clams placed in the wild environment and was a logical first step toward a collaborative effort in the years to come. Both towns wish to pursue the opportunity to realize their independent projects in the interest of expanding shellfish production and harvest for both communities. The HNRD has been actively exploring school link with the Harwich School Department through the Harwich Exchange and Action Resources Team. There is every opportunity to provide a setting for up to ten students to assisting several important areas in the day to day operation of the lab including: understanding the sizing and distribution of shellfish; identifying planktonic food sources; testing water temperature, salinity, dissolved oxygen and developing the annual harbor water quality profile; monitor oil sheens. This data gathering will assist the HNRD effort while at the same time foster the understanding of the Ocean and the importance of its protection.

    Statement of Goals and Objectives

    Goal: To increase the total supply of clams mercenaria mercenaria available for harvesting in Harwich and Brewster waters through optimal operation of the Town of Harwich clam seed rearing system and the widespread distribution of the juvenile stock.

    Objectives:

    · Work toward stabilizing the production of seed quahogs from the Harwich Shellfish Lab by limiting losses through monitoring sources and size distribution. Finding a better trade off between price and size handling capability.

    · Nurture the cooperative arrangement between Harwich and Brewster Natural Resources Departments for growing juvenile clam seed and placement of stock in a suitable grow out environment.

    Goal: To improve existing shellfish rearing techniques by promoting innovative approaches to growing juvenile shellfish.

    A. Establish cooperative arrangement and management innovations within the community for a greater output of juvenile clams by 1999.

    B. Develop a school link between Harwich School Department and the HNRD. This work/study program is being operated by science teacher and department head Troy Hopkins and has received two additional funding grants being given Commuity Foundation of Cape Cod, Inc. through the Cape Cod Community College for this purpose. covering two students and three students are being sponsored by the Regional Employment Board. (Funding for this project has been provided by matching funds from the Cape Cod residents and the Massachusetts Environmental Trust Community Partnershgip Program the Massachusetts Environmental Trust is an environmental philanthropy established by the Massachusetts Legislature in 1988 through the settlement of a federal lawsuit over the pollution of Boston Harbor. The Community Foundation of Cape Cod was founded in 1989 with the goal of expanding and enhancing opportunities for philanthropy on Cape Cod. The mission of the Foundation is to improve the quality of life for the people of Cape Cod by developing permanent and flexible endowment funds to assist nonprofit organization and others respond to the existing and emerging community needs of Cape Cod.)

    Statement of Public Purpose

    It continues to be the expressed intent of this project to increase the supply of hard-shell clams for the benefit of all participants (i.e. harvesters, consumers, and indirect beneficiaries) For Harwich the proposed project will result in significant economic benefits for the public-at-large.

    1.The project’s significant contribution to the supply of shellfish for harvest by recreational and commercial permit holders will improve the region’s image as a place where theses activities are available, thereby keeping it attractive and viable for seafood based tourism, a major industry in the area.

    2.The circulation of the harvested clams through the local economy will have significant economic effects.

    Rationale:

    Using an average est/imated market (wholesale) price for a grown clam of $ .20, and a projected survival rate of 75% (based on actual experience), the proposed 6 million clam target is calculated to represent 4,500,000 clams placed in the wild fishery. If 75% of this amount (or 3,375,000 clams) is actually harvested with 1/3 of the harvest taken by recreational permit holders and 2/3 (2,250,000) taken by commercial permit holders, the dollar value of the commercial harvest would be $450,000. This outcome would not only provide employment and income for many shellfishermen, but the resale of the clams to various end-consumers would also help sustain the jobs involved in such activity. As for the recreational harvesters, many of these are seasonal residents, second homeowners, and retirees - a group which contributes a substantial amount of income to the local economy. Maintaining and increasing their shellfishing opportunities serves to sustain property values and contributes to the overall quality of life in the region.

    Deliverables

    1. Reach the sustainable product of the Harwich upwelling complex at Wychmere harbor 6 x 106 hard shell clams using existing technology and working with a larger input commodity.

    2. Create opportunities for innovation by allowing BNRD space and hook-up in Saquatucket Harbor for the proposed upwelling barge to serve as an experimental grow-out laboratory.

    3. Provide School Link services with the Harwich School Department. The Shellfish Lab at Wychmere Harbor would become a satellite program for the High School Science Department.

    4. Agreement between Harwich and Brewster Natural Resources Departments documenting the arrangement to share the upweller on a need basis.

    5. Different species will be explored for propagation potential in the upweller not limited to sea clams, oysters, bay scallops.

    Plan of Work

    1. February 15, 1998 - Hard Clam seed is ordered from hatchery.

    2. April 15, 1998 - HNRD establishes solidifies school link and prepares documentation for program with High School Science Department.

    3. May 1, 1998 - Shellfish Lab pumps are reconnected and system brought on line to stabilize. Last seasons bedded seed is brought up and inspected for survival, some brought back into lab.

    4. June 10, 1998 - Seed clams are received from hatchery on placed in units.

    5. May - November, 1998 - Juvenile clams reared in upwellers are transferred to marine bottom for additional grow out.

    A healthy clam is our most important product. We find adjustable gardenia nozzle the most controlable "water gun" to wash down tiny clams removing daily buildup of pseudo-feces, breaking up bysal mats and cleaning healthy slime from screens.

    Potential Use

    1. It is likely that the proposed floating upweller barge will help identify the optimum conditions for raising clam seed in an upweller. The barge may relocated by towing from marina-to-marina where water conditions vary in terms of temperature, salinity, depth, ambient nutrients, and other characteristics. Since the clams grow quickly, it will be evident to the highly qualified operators of the system which environments promote the optimum growth and overall health of the clams. The finding from experiments and data collection by the science students under the direction of the school science advisor and Natural Resources Director will be invaluable to the science of aquaculture on Cape Cod by providing the appropriate methodology for clam production in an upweller system. This is significant because their are few available places where stationary upwellers can be efficiently operated but many where floating systems can be successfully deployed. Harwich has clearly moved beyond the experimental stage with the operation of its shellfish laboratory, clearly it is now time that we prove that this production can be consistent.