Volume Number OYSTER RESTORATION SERIES Status of the U by kyliemc


									                                                                                                 Volume 5, Number 1 • 2004

                                                                 to “Oyster Wars”. Harvesters enlisted the services of armed
OYSTER                                                           boats to guard private oyster beds throughout the night,
                                                                 and some states funded their own “Oyster Navy” to keep
RESTORATION                                                      the peace. Shortly after the turn of the 20th Century, over-
                                                                 exploitation caused a precipitous decline in harvests. In the

SERIES                                                           mid to late 1900s, two oyster diseases appeared and
                                                                 devastated already-weakened east coast populations.

Status of the                                                    Today, oysters in Chesapeake Bay – once the nation’s crown
                                                                 jewel of oyster production – have been reduced to 1% of
U.S. Oyster Resource                                             their former abundance. With each passing year, the
                                                                 industry crisis grows because of lost jobs and excess
Jamie L. King, Ph.D., NOAA Chesapeake Bay                        infrastructure. Poor water quality has closed many oyster
Office, Annapolis, MD                                            beds along the Atlantic and Gulf coasts because the oysters
                                                                 are not safe for human consumption. Native oysters on
Kay McGraw, Ph.D., NOAA Restoration Center,                      the Pacific coast survive only in small, remnant populations,
Silver Spring, MD                                                and harvests of native Pacific oysters have been replaced
                                                                 by large-scale aquaculture of non-native oyster species.

                                                                 National and Regional Trends
        hat does the future hold for the nation’s native
oyster species? How will coastal ecosystems be impacted by       Nationwide oyster production has declined significantly
the absence of oysters? What is to become of the economic        from its historic highs in the late 1800s. Over-harvesting,
value and rich cultural heritage of local and regional oyster    water pollution, disease, and mining oyster shell for road
fisheries? This issue of Habitat Connections is the first in a   construction all contributed to the reduction of U.S. oyster
series intended to address these questions by examining          resources. Landings of all oyster species in 1880 totaled
the history, current status, and future prospects of the U.S.    around 154 million pounds. By the 1950s, landings had
oyster resource. Future issues in this series will focus in      dropped to less than half that number, at roughly 60 million
greater detail on topics such as restoration efforts within      pounds. By the end of the century, harvests declined almost
individual regions and the proposed introduction of a non-       another fifty percent to just under 31 million pounds. Total
native oyster species to Chesapeake Bay.

                                                                 The Habitat Connection
Brief History
                                                                    Oysters have a special relationship to habitat because they
From pre-colonial times to present, oysters have been a
                                                                    not only require certain habitat conditions in order to
vital natural resource. Native Americans in coastal areas           survive, they also create habitat. Oyster reefs are the
found oysters to be an abundant and nutritious food                 primary source of hard bottom habitat in many nearshore
source. They used oyster shells as tools, weapons,                  ecosystems that are otherwise dominated by soft
ornaments, and currency. Midden mounds – ancient shell              sediments. Reef habitat is critical, not only for oysters,
piles found at many coastal sites – attest to indigenous            but also for diverse assemblages of other organisms.
peoples’ long-standing reliance on oysters.
                                                                    By virtue of their extraordinary filter feeding
When European colonists arrived on the east coast of North          capabilities, oysters remove plankton, bacteria, and
                                                                    sediment from the water. Due to their ecological
America in the 1600s, they encountered massive oyster reefs
                                                                    importance to so many other organisms, oysters are
that broke the water’s surface at low tide and presented
                                                                    recognized as a keystone species.
navigational hazards for ships in many bays and estuaries.
Early colonists considered oysters an inexhaustible resource.       This tight connection between oysters and habitat is
They used oyster shells for roads, fertilizer, ballast in           why restoration of the nation's oyster resource is
schooners, and mortar for building houses.                          critically important for the ecological health of many
                                                                    coastal ecosystems.
By the post-Civil War era, oysters were considered such a
valuable commodity that competition for the resource lead
landings in 2002 were low although they had increased                       secondary products and services such as shucking and
slightly from the 1991 historic low of 30.8 million pounds.                 packing houses, transport, manufacture of prepared oyster
                                                                            products, and retail sales. For example, oysters worth $1
Underlying these national trends are shifts in the relative                 million in dockside value in Chesapeake Bay generate an
contribution of certain regions and states to the U.S. total.               estimated $36.4 million in total sales, $21.8 million in
From the earliest landing records to the mid-1900s,                         income, and 932 person years of employment1.
Chesapeake Bay was the dominant oyster-producing
region. The initial sharp decline in U.S. landings during the
early 1900s was due almost entirely to a dramatic drop in                   Regional Stories
harvests from Chesapeake Bay. Whereas the Chesapeake
once produced 40 - 50% of the oyster harvest, today it                      Why have the patterns of production for this time-honored
yields only 2% of total landings.                                           culinary delight, cultural icon, and valuable economic
                                                                            commodity changed so dramatically? Changes in regional
From the 1960s to mid-1980s, the Chesapeake and Gulf                        production are the result of many interacting factors: local
regions were the major oyster producers. Harvest levels                     oyster abundance, local and national market forces, fishery
were similar between the two regions, fluctuating around                    management, and fishing industry dynamics (e.g., Gulf
20 million pounds apiece annually. As Chesapeake Bay                        fishermen switching from shrimping to oystering).
landings continued to decline from the mid-1980s to                         Understanding these factors requires a closer look within
present, the Gulf and Pacific regions, primarily the states of              key regions at oysters themselves, their ecological habitats,
Louisiana and Washington, came to dominate U.S. oyster                      and the fisheries based upon them.
production. Louisiana is now the top-producing oyster
state. Since 1990, Louisiana has contributed an average of                  Atlantic Coast
42% of the total annual U.S. harvest.
                                                                            The Atlantic coast includes several regions: New England,
Despite declines in oyster landings, the value of the oyster                Middle Atlantic, Chesapeake, and South Atlantic. The
industry to regional economies remains significant. Annual                  oyster species native to all these regions is the American or
dockside value was around $30 million in the mid-1900s,                     Eastern oyster, Crassostrea virginica, which ranges from the
and reached highs over $90 million per year in the 1990s.                   Gulf of St. Lawrence to Florida and into the Gulf of
The full economic value of oysters goes well beyond                         Mexico. This oyster has been the mainstay of the U.S.
dockside value. In addition to primary sales of the raw,                    oyster industry.
unshucked product, there are economic benefits from
                                                                                               The Eastern oyster is an impressive reef-
                                                                                               builder. The large oyster reefs encountered
  FIGURE 1: OYSTER LANDINGS FROM 1880–2002                                                     by European colonists had been created
                                                                                               over the course of 7,000 years by
                                                                                               generations of Eastern oysters settling as
                                                                                               planktonic larvae on the shells of their
                                                                                               predecessors. Oyster reefs in Atlantic
                                                                                               estuaries exist today as low-lying bars, mere
                                                                                               remnants within the footprints of the
                                                                                               earlier structures. Although it is well
                                                                                               established that over-harvest was the
                                                                                               primary culprit for historic declines, other
                                                                                               factors including oyster disease, habitat loss
                                                                                               and degradation, and poor water quality
                                                                                               now play a role and hinder restoration.

                                                                                               Oyster fisheries along the Atlantic coast
                                                                                               are traditionally based upon harvest from
                                                                                               public and leased bottom. The proportion
                                                                                               varies greatly among states, with some
                                                                                               states favoring a public fishery and others
                                                                                               encouraging private investment on
Figure 1: Oyster landings from 1880 - 2002. Note: US totals prior to 1950 are for the
eastern oyster only; all data are subject to updates and changes. Data from 1950 - present
                                                                                               leaseholds. Oyster production is limited
were obtained from NOAA, NMFS Commercial Fisheries Statistics web site:                        by available substrate (shell material) for
http://www.st.nmfs.gov/st1/commercial/index.html as of Feb. 20, 2004. Historical data were     larvae to settle upon and grow. Some
compiled from unpublished data files supplied by NMFS Commercial Fisheries statistics office   states subsidize their public fishery by
personnel. (Graph by Kay McGraw)                                                               planting shell to catch settling oyster
                                                                                               larvae, then distributing the young spat to

                                                                      Landings vs. Population Data
                                                                      for Oyster Fishery Management
                                                                         Landings are often used to gauge the status of oyster
                                                                         resources because they are relatively easy to obtain, do not
                                                                         require costly population monitoring, and are the most
                                                                         complete dataset available.

                                                                         In reality, however, harvest data are a poor surrogate for
                                                                         population status. Harvest levels can increase or remain
                                                                         stable even while a wild population is in decline. Greater
                                                                         fishing effort from more people or boats entering the
harvest beds. Private growers carry out similar activities to            fishery, or more efficient harvest gear can mask actual
cultivate their leased grounds. Other techniques, such as                reductions in the harvested stock.
off-bottom aquaculture (e.g., oysters grown in bags
hanging from floating surface structures), have been                     Stock assessments based on fishery-independent data are
developed in some locations, but use of oyster beds                      the best way to determine oyster population status.
remains the predominant production method.

Atlantic production is currently at such low levels that the         bottom leases, particularly in Louisiana. Oyster growers
industry infrastructure has all but collapsed. Some once-            assiduously maintain the bottom habitat on their
booming oyster ports are now ghost towns. In Chesapeake              leaseholds, assuring that a constant supply of clean shell
Bay, local harvests are insufficient to supply the few               substrate is available to oyster larvae for settlement. Shell
shucking houses that remain, so they are now processing              planting also occurs on public grounds. Off-bottom and
Louisiana oysters. Oyster business owners wonder how                 pond-based methods of aquaculture are being developed,
long they will be able to keep their doors open with a               but are not yet widely practiced.
limited supply of local product.
                                                                     A major issue for the Gulf industry is human health risk(s)
Gulf Coast                                                           associated with eating raw oysters tainted with Vibrio
                                                                     bacteria. State agencies monitor water quality and
Eastern oyster populations in the Gulf did not experience            periodically close oyster beds to harvest, especially when
the severe historic declines from over-fishing that occurred         heavy rains carry high bacterial loads from the land. The
in the Chesapeake and Middle Atlantic regions. Still, Gulf           industry is working to increase safety with post-harvest
oyster reefs are greatly diminished, and suffer from many            treatments to reduce bacteria.
of the same modern problems including pollution, habitat
degradation, disease, and harvest pressure.                          Pacific Coast
Also like the Atlantic, the Gulf oyster fishery includes both        The native Olympia oyster, Ostreola conchaphila (also
public and leased grounds. Much of the stability in Gulf             Ostrea lurida) is a small oyster, measuring only about 2 - 3
oyster production can be attributed to the many private              inches in length. Unlike the Eastern oyster, the Olympia

Oyster Harvest Production Methods
    PUBLIC FISHERY                             AQUACULTURE                                LEASED GROUNDS
    I   Harvest from natural oyster            “Farming of the sea”                       I   Blending of public fishery and
        beds.                                  I   Private investment - risks must            aquaculture -- uses a public
                                                   be low enough to warrant                   resource but allows exclusive
    I   Usually managed by boat, catch,
                                                   substantial capital outlay for             use of that resource for
        season limits.
                                                   equipment & labor                          private profit.

                                               I   Increased production due to            I   Involves
                                                   protection from predators and              various oyster
                                                   ideal growth conditions.                   production

National Oceanic and Atmospheric Administration
National Marine Fisheries Service
Office of Habitat Conservation
1315 East-West Highway
Silver Spring, MD 20910–3282

(301) 713–0174

oyster is not a reef-builder. It ranges along the west coast     oyster resources. NOAA leads several programs involved in
of North America from Alaska to Baja California, occurring       oyster research and restoration. Key among these are the
on rocks in intertidal habitats; mud flats and gravel bars at    Restoration Center, Sea Grant, and Chesapeake Bay Office.
the mouths of small rivers; and subtidal beds in deeper
bays.                                                            The NOAA Restoration Center has funded 75 oyster
                                                                 restoration projects in 15 states around the country. Nearly
Olympia oyster populations were over-harvested along the         17,000 volunteers participated in these restoration efforts.
Pacific coast in the 1800s, and further declined due to poor     The Restoration Center is the only office within NOAA
water quality in the early 1900s. Subsequent efforts to          solely devoted to restoring coastal and marine habitats
sustain a viable oyster industry in the northwest led to         that support the nation’s fisheries and other public
establishment of a significant hatchery-based aquaculture        resources. Restoration Center projects involve citizens and
industry. This industry primarily cultivates the non-native      scientists in restoring oyster habitats and raising awareness
Pacific or Japanese oyster, Crassostrea gigas, which was first   of the important ecological role oysters play in coastal
imported early in the 20th century. The Eastern oyster and       ecosystems.
a variety of other non-native species (e.g., Kumamoto
oyster, European flat oyster) are also cultivated in smaller     NOAA Sea Grant established an Oyster Disease Research
numbers as specialty items for the half-shell market.            Program to find solutions for oyster diseases. This long-
                                                                 term, national program supports innovative research to
The non-native Pacific oyster is now the most important          develop techniques to combat oyster disease in order to
commercial oyster species in the region, constituting 99%        improve restoration and stock enhancement.
of all west coast oyster production. The vast majority of
Pacific oysters come from Washington state, which has the        The NOAA Chesapeake Bay Office works closely with
largest concentration of oyster farms in the nation.             federal and state agencies in Maryland and Virginia to
                                                                 implement large-scale oyster restoration within the
                                                                 Chesapeake Bay. The work involves hatchery production of
NOAA Restoration Efforts                                         oyster seed, bottom rehabilitation, and a variety of
                                                                 management strategies including sanctuaries, harvest
NOAA is working on several fronts to reverse nationwide          reserves, and tributary-scale genetic rehabilitation of oyster
declines in native oyster populations and their habitats.        stocks.
Because oyster populations occur within state waters,
NOAA does not have jurisdiction over the management of           Subsequent articles in this Habitat Connections series will
oyster fisheries. Rather, the agency’s focus has been to         explore these novel programs, describe partnership efforts,
fund research, monitoring, and habitat restoration to            explain current research results, and discuss future
improve the understanding and stewardship of the nation’s        prospects for NOAA oyster recovery effort.


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