Oyster Decline OVERVIEW: For more than a century, oysters made up one of the Bay's most valuable commercial fisheries. The interaction of over‐harvesting, disease, sedimentation and poor water quality has since caused a severe decline in their numbers throughout the Chesapeake. The Bay's native oyster population is now estimated to be just 1‐2 percent of its historical abundance. The decline in the Bay's native oyster population is often illustrated in terms of its impact on water quality: In the late 19th century, the native oyster population could filter a volume of water equal to that of the entire Bay every three to four days; today's depleted population takes nearly a year to filter the same volume. CONTRIBUTING FACTORS: Historic fishing practices. Oyster diseases MSX and Dermo. Loss of habitat due to pollution from excess nutrients and chemical contaminants. Sedimentation from removal of forests and runoff from development and agricultural lands. Natural predators, such as flatworms and cownose rays. ENVIRONMENTAL PROBLEM: The decline of oysters removed a major source of filtration from bay waters, causing increasingly murky and unhealthy water for humans and animals. DISCUSSION QUESTIONS: Who/What does this issue affect? Draw a web with “Oyster Decline” in the middle. What are some issues (a disagreement about whether this is a problem or not or a disagreement about how this problem can be solved) that stem from this environmental problem? What are at least three reasons oysters are beneficial to the Bay? In what ways are humans affected by oyster decline? How are local agencies working to restore the oyster population? SOURCES: Blankenship, Karl. “Order for improved habitats goes beyond better water quality.” Bay Journal. October 2009. 20 October 2009 <http://www.bayjournal.com/article.cfm?article=3670&print=yes. Accessed October 20, 2009>. Discusses “critical living resources” as important animal species not commonly mentioned in the Bay discussion like hellbenders, American eels, and Louisiana waterthrush. Talks about habitat improvements as the key to Bay health. Danes, Ceri Larson. “Living shoreline to be one‐of‐a‐kind.” delmarvaNOW.com. 19 October 2009. 20 October 2009 <http://www.delmarvanow.com/article/20091019/NEWS01/910190313/‐1/newsfront2/Living‐shoreline‐to‐be‐one‐of‐a‐ kind>. Covers a project on the eastern shore of Virginia to create a living shoreline using plants for stabilization instead of bulkheads as an example for other cities. Haviland, Mark W.. “USACE decision sets focus for Chesapeake Bay oyster restoration”. US Army Corps of Engineers Norfolk District. 14 August 2009. 20 October 2009 <http://www.army.mil/‐news/2009/08/14/26041‐usace‐decision‐sets‐focus‐for‐ chesapeake‐bay‐oyster‐restoration/>. Discusses the decision to not introduce non‐native oyster to the Bay and lists other options involved in the Corps study. Moore, Kirk. “Oyster beds, once the pearl of Shore fisheries, poised to rebound.” APP.com. 17 October 2009. 20 October 2009 <http://www.app.com/article/20091017/NEWS/910170314/1004/NEWS01>. Discusses the success of New Jersey and Delaware Bay oyster restoration and interesting ideas to repeat in the Chesapeake Bay like the shell planting program. Moorhead, Jeremy. “’Waterman’s’ weapon against pollution: Oysters.” CNN. 2008. 20 October 2009 <http://www.cnn.com/2009/TECH/04/17/gsif.chesapeake.restoration/index.html>. Interview with an oyster farmer and Virginia oyster and fishery scientist for the Chesapeake Bay Foundation on oyster sustainability, efforts of oyster restoration by the CBF, and the importance of oysters in the Bay ecosystem. “Native Oysters”. NOAA Chesapeake Bay Office. 29 February 2008. 20 October 2009 <http://noaa.chesapeakebay.net/NativeOysters.aspx>. Briefly covers the history of the oyster fishery, natural history on the American oyster, and the history of oyster restoration efforts with links to oyster management plans and native oyster restoration techniques. “Oyster Harvest”. Chesapeake Bay Program. 15 September 2009. 20 October 2009 <http://www.chesapeakebay.net/oysterharvest.aspx?menuitem=14701>. Explains why the oyster population has declined and how oyster harvesting and poor water quality affects oysters. “Oyster Restoration.” Chesapeake Bay Foundation. 2009. 20 October 2009 <http://www.cbf.org/oysters>. Great information on restoration efforts through the Chesapeake Bay Foundation’s oyster restoration program including oyster gardening. Wood, Pamela. “State sets new record for oyster restoration.” HometownAnnapolis.com. 12 October 2009. 20 October 2009 <http://www.hometownannapolis.com/news/top/2009/10/12‐12/State‐sets‐new‐ record‐for‐oyster‐restoration.html>. Covers the success of University of Maryland Center for Environmental Science’s Horn Point Lab in Cambridge in their oyster spat program including the use of “reef balls” and volunteer oyster gardeners.
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