The Massachusetts Oyster Project For Clean Water Restoring oysters to their natural range to improve harbor water quality


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The Massachusetts Oyster Project For Clean Water

  • Restoring oysters to their natural range to improve harbor water quality


Our Goal

  • Re-establish protected oyster reef populations on suitable areas on the Charles, Fort Point Channel, Mystic, Chelsea Creek, Neponset, Malibu Bay, Harbor Islands and other areas to improve water quality, offset run-off pollution, attract other sea life and help perpetuate the species.

  • These oysters will be placed in sanctuary areas closed to shell fishing and are not intended to be harvested- ever.



Oyster Benefits

  • Filtering water in tidal estuaries

    • 30 gallons per oyster per day
    • Feeding on phytoplankton and silt
    • Improves water clarity
    • Offsetting impact from sewer overflows and other manmade pollutants
    • Capturing nitrogen, algae and bacteria
    • Offsetting ocean acidification
  • Cleaner water attracts other sea life and people



Oyster History

  • Oysters once prevalent in Boston Area

    • Mystic and Charles Rivers had abundant beds.
    • Very popular food source for native Americans, colonial times and up through mid 19th century
      • Easy to harvest
      • Kept and shipped with ease
      • Surprisingly non-filling
    • Back bay reef may have served as food source for the poor


The historic records confirm oyster prevalence in Boston Harbor

  • Boston Massacre trial records mention oysters shells being thrown and an oysterman being injured.



Oyster Demise

  • Loss of habitat- through fill

  • Misuse- oyster shells and sometimes whole oysters were spread on fields to reduce soil acidity

  • River subjugation-protective dams convert significant areas of Back Bay and Mystic Rivers to fresh water.

  • Pollution- sewage flows, river silt, chemicals

  • Over-harvesting- feeding humans



Our Non-Profit

  • Formed in 2008 to restore oysters

  • All volunteer

  • Obtained permits from the Massachusetts Division of Marine Fisheries

  • Has learned a great deal

  • Continues to evolve

  • We stress

    • Water Quality
    • Biodiversity
    • More Fish


Why Oysters to Clean Water?

  • Water clarity has improved dramatically and is improving thanks to Boston Water and Sewer & MWRA projects.

  • But there still is waste entering the harbor through Combined Sewer Outflows (CSOs) and surface run-off.

    • When there is a heavy rain, the water volume exceeds the capacity of pipes to treatment facilities.
    • Thus domestic sewage and storm water may be diverted to the CSOs and into the harbor.
    • This waste can raise nitrogen levels and contribute to algae blooms.
  • There also will be an ongoing problem with contamination from surface run-off.

  • Downstream this can lead to beach closings or limitations on activity on the water sheet.



CSO’s and surface runoff remain a problem.



Oyster Reefs

  • Have 50 times the surface area of flat bottom

  • Home to over 100 other species including anemones, mussels, eels, shrimp and even lobsters

  • These other species are food sources for fish including striped bass and blue fish

  • Cleaner water helpful for eelgrass a key plant in the harbor ecosystem



Oyster Reefs Draw Other Sea Life- Bluefish, Sea Bass, Flounder, Eels

  • Hard substrate

  • Vertical structure for shelter

    • Small fish
    • Grass shrimp
  • Food

  • Water quality regulation



Oysters can triple the number of fish!

  • Abstract  Oyster-shell plantings were made on formerly productive bottom to determine the practicability of securing an oyster set in this area and to test the hypothesis that the availability of game fish could be improved by artificially modifying the habitat in Chincoteague Bay, Maryland. Fish populations were trapped over planted and unplanted control areas with the same effort from August to November in 1958 and 1959. Fourteen species of saltwater fish were recorded in the planted and control areas, of which the black sea bass,Centropristes striatus, was the dominant species.

  • The planted areas yielded about three times as many fish as the controls during the two years. Black sea bass numbers were much greater on planted areas than on control areas. The planted area also produced more species than the unplanted area.

  • More fish were caught over both planted and control bottoms during 1959 than in 1958, due partially to improved trap design. There is some evidence of improvement in the availability of fish over a planted area that has aged for a year. It is concluded that oyster-shell plantings significantly concentrated and increased numbers of fish over restricted areas, when compared to unplanted areas.



Progress to Date

  • 2008 Phase I Pilot-

    • Placed 150,000 oysters at the mouth of the Charles River off of the North End.


Placement Event Media Coverage

  • TV- Channel 4, 5, and 7

  • Radio NPR- WBUR

  • Print



Placement Event Media Coverage



Placement Follow up

  • Results

    • 6 months later 50% surviva
    • A bit more silt than we would like
    • Silting from Spring run-off reduced survival to 20%
  • Harbor surprisingly vital

    • Mussels, crabs, lobsters and starfish
    • Fish


Oysters on the Bottom



The Survivors of the Class of 2008 Grew



Caged Oysters Summer 2009

  • Hung off deck in Charles River

  • Tremendous growth in 23 days

  • Lots of other sea-life. shrimp, crabs etc.



Year 1 Learnings

  • Oysters could survive the winter

  • Oysters can grow

  • We need to keep them out of the silt

  • We have not yet shown reproduction



2009

  • Monitor success or failure of Charles pilot

    • 20% survival- No sign of reproduction
  • Placed 50,000 more oysters October 25

  • Start Pilot at Dorchester Yacht Club with Professor AnaMarija Frankic of UMass Boston.

  • Get oysters on display at the New England Aquarium- educate!



Mass Oyster 2009 Placements (In 2008 the boats drifted too far out in the Channel, and the oysters wound up in silt y areas that impeded there growth.)

  • Oysters placed in three locations in 2009.



Charles River Oysters 2010

  • In three formats

    • Loose on bottom (20% survival)
    • In cages on bottom (50% survival)
    • In milk crates hung from docks (80% survival)
      • Best way to get data without divers
  • Expanding techniques to gather more data

    • How big a factor is predation?


Oysters in Malibu Bay Dorchester

  • Oysters were placed on November 26th 2009 under the auspices of a scientific permit from Massachusetts Division of Marine Fisheries.

  • The oysters were split into two groups. Each group was suspended off of a dock in two stacked milk crates.

  • The milk crates were checked periodically and the oysters were measured.

  • Two sets of oysters were placed.

  • Oysters removed on October 1, 2010 per the request of DMF.



Boston Harbor Map



A special “Thank you” to Al and the membership of Dorchester Yacht Club.



Oyster Size



Oyster Size Normalized Histograms



Length Standard Deviation



Normalized Size Histogram



Oyster Weight in Pounds



Water Temperature Data



Conclusions

  • Oysters can survive in Dorchester’s Malibu Bay in a caged environment.

  • Oysters can grow at a healthy pace in Dorchester’s Malibu Bay while suspended in the water column.

  • We saw no sign of reproduction. However, we were not anticipating it. Further study would be required to confirm that reproduction is possible in this environment. However, the impressive growth may indicate favorable conditions.

  • Given that oysters once were prevalent throughout Boston Harbor and that there are significant environmental benefits from their presence, further research and restoration efforts on this topic may be warranted.



Charles River Oyster Growth



Charles River Oyster Survival



Charles River Oysters



Charles Histograms



Temperature Comparisons



As an organization we are seeking

  • To generate meaningful data.

  • To optimize the way we place oysters

    • We are limited to one location that may not be the best
    • We have some history and learnings
  • To publicize our work and shape the discussion through scientific meetings and the web.

    • Website, blog, slideshare, (nitrogen paper)


Open Questions

  • Will we have enough adult oysters in 2011 to obtain a set and see reproduction?

    • If we do get a set, will the spat be able to settle and grow successfully?
    • Will the population be at Critical Mass?
  • Will we be able to solve the predation challenge?

    • Placing spat on shell in 2011-
    • Placing the oysters loosely when larger and even more carefully?
  • Will MSX limit the lifespans of our oysters?

  • Will we continue to be able to obtain regulatory approval?

    • Continue at current site?
    • Begin in other locations?


General Reflections

  • People like what we do

    • Intuitively it makes sense- people get it.
    • It is a natural, green solution to the problem
    • Attracting funds has not been hard- we have turned down $54,000 in grant funding to date.
  • We are changing the way people view the harbor.

    • Recognize that it is coming back vital.
    • We are getting people in/on the harbor.
  • We have had no problems with pilferage or vandalism.

  • Our biggest challenge to expanding the program is the Division of Marine Fisheries

  • We need to work more on a national basis to help set the policy and agenda.



Questions




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