Presentation on theme: "OYSTER REEF DESTRUCTION AND RESTORATION JULIE PAULSEN, AUBREY FELDMAN, DAVID AMERO."— Presentation transcript:
OYSTER REEF DESTRUCTION AND RESTORATION JULIE PAULSEN, AUBREY FELDMAN, DAVID AMERO
A Brief Introduction Oyster reefs are common submerged habitats located in many parts of the world Oyster reefs are built primarily through the successive reproduction and subsequent settlement of generations of the eastern oyster (Crassostrea virginica) Reef structures consist of staggering numbers of individuals Luntz (1960) estimated that within a single square yard of oyster reef, there were 5,895 individual oysters As successive generations settle and grow, reefs become highly complex, containing many structural irregularities and infoldings Oyster reefs are extremely important entities as they provide numerous benefits to the environment and enhance our lives
Oyster Reef Range, United States Source: chesapeakebay.noaa.gov
Ecological Importance Oyster reefs are the temperate version of coral reefs, and are often referred to as “ecosystem engineers” Oysters acts as a “keystone species” and their dynamic behavior serves to structure and maintain healthy, coastal ecosystems The conjugation of individual oysters to form a collective reef provides a structured habitat for a whole community of organisms Extensive, irregular surfaces of a reef provide 50 times more surface area compared to a similar sized flat bottom Protection for spawning and mating Home to a multitude of different organisms Oyster reefs are important in the maintenance of biological diversity in estuaries
Ecological Importance Oyster reefs are vital to overall health of surrounding coastal habitats Reefs influence patterns of currents Provide “buffer” between coastal habitats and potential water destruction Clean water by filtering out particulates Remove excess phytoplankton, preventing eutrophication Filters out excess Nitrogen Allows for sunlight and oxygen to penetrate layers Important in nutrient and energy cycling Critical link in food web between organisms of varying trophic levels
The Past “Oysters once grew naturally all along the Brooklyn shore, and in the East River; all around Manhattan Island; up to the Hudson as far as Sing Sing; Out to the Jersey Shore from that point to Keyport, N.J., and in Keyport, Raritan, Newark, and Hackensack Rivers; all around Staten Island, and on many reefs and wide areas of bottom between Robyn’s Reef and Jersey City.” -Ernest Ingersoll, 1887 Naturalist Ernest Ingersoll studied shellfish in the United States and Canada during the 19 th century, and his reports indicated an abundance of oysters along the east coast of North America He described how they “thrive in endless profusion” in some areas, especially off the south-eastern coast
The landmark pile of oyster shells at J.S. Darling & Son, circa Founded in the 1800s on the Chesapeake Bay, this was the world’s largest oyster plant during its peak. It Shut down during the 1970s. Source: Norfolk Public Library VA Digital Collection
Now, here comes the bad news…
Steady decline in yields have been recorded during the 20 th century Research shows that in 70% of the 144 bays studied all over the world, reefs are less than 10% of their prior abundance. It is estimated that 85% of oyster habitats around the world have been destroyed, and that most of the remaining populations are in poor condition (Beck et al. 2011) Research done by Professor Mark Luckenbach of the Virginia Institute of Marine Sciences, “shows that oyster reefs are the most threatened of all shallow-water, structured habitats—more so than coral reefs, mangroves, or wetlands.” In the Chesapeake Bay, oyster populations are estimated to have declined by 99.7% since the early 1800s (Wilberg et al. 2011).
Global Conditions of Oyster Reefs Source: Beck et al. 2009
Source: National Marine Fisheries Services Annual Commercial Landing Statistics
What is to blame ? Natural events (i.e. hurricanes and native predators) Man-made activities pose a much larger threat
Natural and Human Threats Source:
Our practices have caused severe damage and led to enormous losses of oyster reefs worldwide, many of which are damaged beyond repair
Overharvesting and destructive fishing practices Harvested for their role as a food source, as well as for the use of their shells Using a dredge to harvest oysters is especially harmful Levels the 3D reef structures that prevent oysters from being smothered by sediment Introduction of non-native marine species Exposes them to new and harmful diseases and parasites Dermo (perkinsiosis) MSX (Haplosporidium)
Offshore gas and oil industry Pipelines and oil platforms have failed for decades, spilling millions of gallons of oil into habitats 2010 BP Deepwater Horizon disaster Hurricane Katrina – 44 individual oil spills caused by damage inflicted Urban costal development Vulnerable reefs are buried, at and accelerated pace, by loosened and dispersed sediment The natural hydrology alteration, due to engineered shipping channels and dredged navigation waterways, creates salinity levels unsustainable for populations Excess nitrogen present in habitats due to the fertilized agricultural land along the coast creates oxygen-deprived “dead zones” that kill off oysters
Amongst all the negative, there is a bright side… Recent research has demonstrated that large-scale reef restoration is plausible and that restored oyster reefs are functionally comparable to natural reefs!
Restoration Experiments with oyster seed and shell planting in the Chesapeake Bay began in : The Maryland Board of Natural Resources Oyster Management Plan was developed 1993: Virginia released hatchery-reared disease-resistant oysters to try and restore the population 2000: Maryland, Pennsylvania, Virginia, Washington D.C., and the federal government signed the Chesapeake 2000 Agreement 2009: Chesapeake Bay Protection and Restoration set future goals, aiming to restore oyster populations in 20 Chesapeake tributaries by 2025 (Executive Order No , 2009)
US Army Corps Get Involved! US Army Corps. Of Engineers Plan: “Large scale, concentrated oyster restoration throughout the Chesapeake Bay and its tributaries.” (USACE 2012) In 2013, USACE reported that it had restored 503 acres of oyster habitat in Maryland and 389 acres in Virginia 30 more acres planned to be accomplished in 2014 Cannot budget beyond 2015
Experimental Oyster Reef Design, Hudson River Source: hudsonriver.org
Measuring Success Measuring commercial oyster yield is insufficient Restoration of ecosystem functions is the primary goal: “Many years of post-restoration monitoring will likely be necessary” (Allen et al. 2011) 4 Universal Metrics established: Reef Areal Dimensions, Reef Height, Oyster Density, Oyster Size- Frequency Distribution (Baggett et al. 2014) “A mean density of 50 oysters/m 2 and 50 grams dry weight/m 2, containing at least two year classes and covering at least 30% of the reef area, provides a reasonable target operational goal for reef level restoration” (Mann et al. 2007)
Source: San Francisco Chronicle - Feb 4, 1999
Who needs ‘em anyways? UHM…EVERYONE!!!
So what’s in it for us? If we protect our oyster reef habitats around the world, we reap the benefits of the countless services and goods that they provide us with!
Marine Habitat and Oyster Harvest Increase in oyster harvest and marine fisheries production Food source for humans Generates revenue for commercial industry and creates jobs in seafood processing One acre of oyster reef increases fisheries catch values by $4,200 annually As the foundation of a food chain, oyster reefs support a $2.4 billion fishing industry and more than 200,000 jobs
Water Filtration Oysters are filter feeders that feed upon suspended particles, pumping high rates of water flow, making them an important biofilter Oysters filter excess nitrogen and other chemical pollutants from water Each individual oyster filters up to 1.5 gallons of water per hour, a service otherwise carried out by expensive wastewater treatment plants Each acre of oyster reef provides $6,500 in denitrification services annually Removal of nitrogen, which would otherwise contribute to marine “dead zones” Filtration of suspended sediments allows sunlight to reach underwater floor to facilitate the growth of marine grasses necessary to hold wetlands in place Filtration provides clean, safe and beautiful areas for recreation and tourism, a multi-billion dollar industry
Shoreline Protection Stabilize bottom sediments, reduce wave energy and prevent erosion Fortify wetlands that protect the coast against flooding caused by storm surges Storm protection provided to maintain success of communities and businesses on the coast Protection of valuable oil and gas pipeline infrastructure near shore, which is a huge economic and energy security for the entire U.S.
References Allen, Steve et al. “Restoration Goals, Quantitative Metrics and Assessment Protocols for Evaluating Success on Restored Oyster Reef Sanctuaries.” Sustainable Fisheries Goal Implementation Team of the Chesapeake Bay Program. (2011) Baggett, L.P. et al. “Oyster Habitat Restoration Monitoring and Assessment Handbook.” The Nature Conservancy. (2014) Beck, Michael W. et al. "Oyster Reefs at Risk and Recommendations for Conservation, Restoration, and Management." BioScience 61.2 (2011): Breitburg, D L, L D. Coen, M W. Luckenbach, R Mann, M Posey, and J A. Wesson. "Oyster Reef Restoration: Convergence of Harvest and Conservation Strategies."Journal of Shellfish Research. 19 (2000): Print. Dame, Richard F, Richard G. Zingmark, and Elizabeth Haskin. "Oyster Reefs As Processors of Estuarine Materials." Journal of Experimental Marine Biology and Ecology (1984): Print.
References "Ernest Ingersoll." Autores. Lecturalia RSS, Foster, C D, C D. Foster, C D. Foster, C D. Foster, Mary-Elizabeth C. Miller, Kate L. Sheehan, Kate L. Sheehan, Kenneth L. Heck, and Sean P. Powers. "Impacts of Oyster Reef Restoration on Primary Productivity and Nutrient Dynamics in Tidal Creeks of the North Central Gulf of Mexico." Estuaries and Coasts (2010): Print. Grabowski, Jonathan H., and Charles H. Peterson. "Restoring oyster reefs to recover ecosystem services." Ecosystem engineers: plants to protists (2007): Henderson, Jim, and Jean O'Neil. Economic values associated with construction of oyster reefs by the Corps of Engineers. No. ERDC-TN-EMRRP-ER-01. ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS, Hill, K. "Oyster Reef Habitats." Smithsonian Marine Station at Fort Pierce, 23 June 2002.
References Ingersoll, Ernest. "The Oyster, Scallop, Clam, Mussel, and Abalone Industries." The Fisheries and Fishery In dustries of the United States Vol. II (1887): Kellogg, M.L, J.C Cornwell, M.S Owens, and K.T Paynter. "Denitrification and Nutrient Assimilation on a Restored Oyster Reef." Marine Ecology Progress Series. 480 (2013): Print. Kroeger, Timm. "Dollars and Sense: Economic Benefits and Impacts from two Oyster Reef Restoration Projects in the Northern Gulf of Mexico." The Nature Conservancy, Arlington, VA (2012). Lenihan, Hunter S., and Charles H. Peterson. "How habitat degradation through fishery disturbance enhances impacts of hypoxia on oyster reefs." Ecological Applications 8.1 (1998): Malmquist, David. "Loss of Oyster Reefs a Global Problem, but One with Solutions." Virginia Institute of Marine Science, 3 Feb
References Mann, Roger, and Eric N. Powell. "Why Oyster Restoration Goals In The Chesapeake Bay Are Not And Probably Cannot Be Achieved." Journal of Shellfish Research 26.4 (2007): "Oyster Biology and Ecology." SCORE. South Carolina Oyster Restoration and Enhancement, n.d. "Oyster Reefs - Oysters - Chesapeakebay.noaa.gov." Oyster Reefs - Oysters – Chesapeakebay.noaa.gov. National Oceanic and Atmospheric Administration, n.d. Pierson, K.J, and D.B Eggleston. "Response of Estuarine Fish to Large-Scale Oyster Reef Restoration." Transactions of the American Fisheries Society (2014): Print. Stokes, Shawn, et al. "RESTORING GULF OYSTER REEFS." (2012).
References Wilberg, Michael J. et al. "Overfishing, Disease, Habitat Loss, and Potential Extirpation of Oysters in Upper Chesapeake Bay." Marine Ecology Progress Series 436 (2011): USACE Baltimore and Norfolk Districts. “Chesapeake Bay Oyster Recovery: Native Oyster Restoration Master Plan.” U.S. Army Corps. Of Engineers. (2012)