903R89010
Chesapeake Executive Council
Chesapeake Bay
Oyster Management Plan
U.S. Environmental Protectioi A0e«i
Region III Information Resource
Center (3PM52)
841 Chestnut Street
Philadelphia, PA 191W
Chesapeake
Bay
Program
Agreement Commitment Report
TD
225
.C54 ;
"III July 1989
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Chesapeake Bay Oyster Management Plan
An Agreement Commitment Report from
the Chesapeake Executive Council
U.S. Environmental Protection Agency
Region III Information Resource
Center (3PM52)
841 Chestnut Street
Philadelphia, PA 19107
Annapolis, Maryland
July 1989
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ADOPTION STATEMENT
We, the undersigned, adopt the Chesapeake Bay Oyster Management Plan, in fulfillment
of Living Resources Commitment Number 4 of the 1987 Chesapeake Bay Agreement:
"...by July 1989, to develop, adopt, and begin to implement Bay-wide
management plans for oysters, blue crabs, and American shad."
We agree to accept the Plan as a guide to protecting, restoring, and enhancing the oyster
resource for long-term ecological and economic benefits. We further agree to work together to
implement, by the dates set forth in the Plan, the management actions recommended to address:
(1) harvest decline and overharvesting; (2) recruitment; (3) disease mortality; (4) low production
from leased ground; (5) habitat degradation; (6) shellfish sanitation problems; (7) market stability;
and (8) repletion efforts.
We recognize the need to commit long-term, stable financial support and human resources
to the task of protecting, restoring, and enhancing the oyster fishery. In addition, we direct the
Living Resources Subcommittee to review and update the Plan yearly and to prepare an annual
report addressing the progress made in achieving the Plan's management recommendations.
Date
For the Commonwealth of Virginia
For the State of Maryland
For the Commonwealth of Pennsylvania
For the United States of America
For the District of Columbia
For the Chesapeake Bay Commission
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TABLE OF CONTENTS
ACKNOWLEDGEMENTS ii
EXECUTIVE SUMMARY ill
INTRODUCTION vi
SECTION 1. BACKGROUND 1
American Oyster - Introduction 1
FMP Status and Management Unit 1
Fishery Parameters 1
Biological Parameters 2
Habitat Requirements 2
Habitat Issues 2
The Fisheries 3
Economic Perspective 3
Resource Status 6
Laws and Regulations 7
Status of Traditional Fishery Management Approaches 11
Data and Information Needs 12
References 12
SECTION 2 . OYSTER MANAGEMENT 15
A. Goals and Objectives 15
B. Problem Areas and Management Strategies 16
1. Harvest Decline and Overharvesting 16
2. Recruitment 18
3. Disease Mortality 19
4. Leased Ground Production 20
5. Habitat Issues 22
6. Shellfish Sanitation 23
7 . Market Production 25
8 . Repletion Program 26
FIGURES
1. Maryland Commercial Landings for Oysters from the
Chesapeake Bay 4
2. Virginia Commercial Landings for Oysters from the
Chesapeake Bay 5
Preparation of this document was funded in part by the Coastal
Resources Division, Tidewater Administration, Maryland
Department of Natural Resources, through a grant from the
Office of Ocean and Coastal Resources Management, National
Oceanic and Atmospheric Administration.
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ACKNOWLEDGEMENTS
Development of this management plan is the result of concerted
efforts by members of the Fisheries Management Plan Workgroup
(FMPW), particularly by providing direction for and review of the
plan. Staff from the Maryland Department of Natural Resources
(DNR), Tidewater Administration, and the Virginia Marine Resources
Commission (VRMC) authored the plan and addressed comments on the
draft versions. Contributing DNR staff included Nancy Butowski,
Harry T. Hornick, Phil Jones, Randy Schneider and Harley Speir.
Mark Bundy provided assistance with economic aspects of the
fishery. VRMC staff included Erik Earth, Lewis Gillingham, Roy
Insley, Robert O'Reilly, Randy Owens, Ellen Smoller, Jack
Travelstead, and Lyle Varnell. Thanks are also due to Verna
Harrison and Ed Christoffers for guiding the plan through the
development and adoption process. Finally, we are grateful to
members of other committees and workgroups associated with the
Chesapeake Bay Program and the public who commented on the plan.
Members of the Fisheries Management Plan Workgroup are:
Dr. Erik Barth, Virginia Marine Resources Commission
Mr. K.A. Carpenter, Potomac River Fisheries Commission
Mr. James Collier, D.C. Department of Consumer & Regulatory Affairs
Mr. William Goldsborough, Chesapeake Bay Foundation
Mr. J. W. Gunther, Jr., Virginia Waterman
Mr. Robert Hesser, Pennsylvania Fish Commission
Dr. Edward Houde, UMCEES/Chesapeake Biological Laboratory
Mr. W. Pete Jensen, MD Department of Natural Resources
Mr. J. Claiborne Jones, Chesapeake Bay Commission
Dr. Victor Kennedy, UMCEES/Horn Point Environmental Laboratory
Dr. Romauld N. Lipcius, Virginia Institute of Marine Science
Dr. Robert Lippson, NOAA/National Marine Fisheries Service
Dr. Joseph G. Loesch, Virginia Institute of Marine Science
Dr. Charles F. Lovell, Jr., M.D., Virginia
Dr. Roger L. Mann, Virginia Institute of Marine Science
Mr. Richard Novotny, Maryland Saltwater Sportfishermen1s Assoc.
Mr. Ed O'Brien, MD Charter Boat Association
Mr. James W. Sheffield, Atlantic Coast Conservation Assoc. of Va.
Mr. Larry Simns, MD Watermen's Association
Dr. William Van Heukelem, UMCEES/Horn Point Environmental Lab.
Ms. Mary Roe Walkup, Citizen's Advisory Committee
11
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EXECUTIVE SUMMARY
Introduction
One of the strategies for implementing the Living Resources
Commitments of the 1987 Chesapeake Bay Agreement is to develop and
adopt a series of Bay-wide fishery management plans (FMPs) for
commercially, recreationally, and selected ecologically valuable
species. The FMPs are to be implemented by the Commonwealth of
Pennsylvania, State of Maryland, Commonwealth of Virginia, District
of Columbia, and Potomac River Fisheries Commission as appropriate.
Under this strategy, a timetable was developed for completion of
fishery management plans for several important species. Oysters,
blue crabs, and American shad were given highest priority, with
plans due for these species in July 1989.
A comprehensive approach to managing Chesapeake Bay fisheries
is needed because biological, physical, economic, and social
aspects of the fisheries are shared among the Bay's jurisdictions.
A Fisheries Management Plan Workgroup (FMPW), under the Chesapeake
Bay Program's Living Resources Subcommittee, was formed to address
the commitment in the Bay Agreement for Bay-wide management plans.
The FMPW is composed of members from government agencies, the
academic community, and public interest groups from Pennsylvania,
Maryland, Virginia, and the District of Columbia.
Development of Fishery Management Plans
A fishery management plan is a dynamic, ongoing process to
wisely use a fishery resource. Each of the fishery management
plans prepared under the 1987 Chesapeake Bay Agreement is a concise
summary of the fishery under consideration, problems and issues
that have arisen, and recommended management actions.
The process of developing a management plan incorporates
public and scientific evaluation, and appropriate governmental
approvals. After an FMP is adopted by the Executive Committee, an
implementation plan will be developed to provide more detail on
actions that participating jurisdictions will take and the
mechanisms for taking these actions. In some cases, regulatory
and legislative action will have to be initiated, while in still
others, additional funding will be required. An annual review of
each FMP will be conducted, under the auspices of the Living
Resources Subcommittee, to incorporate new information and to
update management strategies.
111
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Goal of the Chesapeake Bay Oyster Management Plan
The goal of the Chesapeake Bay Oyster Management Plan is to
increase the baywide stocks of oysters by initiating short- and
long-term management actions, in order to enhance the ecological
value of the resource and to help maintain a viable fishery.
Problem Areas and Management Strategies
Problem l: Harvest Decline and Overharvesting. The Chesapeake Bay
oyster harvest has been generally unstable and declining,
culminating in all-time low harvests and dockside value during each
of the past few years. Advances in gear technology have
contributed to the problem, as has mortality due to oyster
diseases. Many traditionally productive areas have been lost or
diminished, resulting in even more concentrated fishing effort.
The average catch per man-day is lower than the permitted daily
limits, signalling that the limits are no longer an effective means
of conserving the oyster resource.
Strategy 1: Oyster harvest from public bars is governed by the
quantity and distribution of natural spat set, and by subsequent
survival to market size. To increase the number of oysters
reaching market size, harvesting effort needs to be stabilized and
monitored, harvest levels need to be set commensurate to the
resource status, and broodstocks should be protected by closing and
opening harvesting areas as needed.
Problem 2: Recruitment. The repletion progams in Maryland and
Virginia are dependent largely on natural spatfall. For the past
two decades, natural spat set has been erratic, generally low, and
of limited geographic range compared to historic figures. Strong
reproductive years have been hurt by harvest pressure, poor water
quality and habitat conditions, and oyster diseases.
Strategy 2: Repletion efforts need to continue but will be
evaluated to increase their efficiency. In order to augment
natural reproduction, plantings of shell for cultch should
continue, as should moving seed oysters to growing areas. Hatchery
production for research and rehabilitation projects need to be
maintained and possibly expanded, and aquaculture efforts should
be supported. Research needs to be conducted on reconstruction of
natural oyster bars and on the relationship between adult oyster
density and recruitment.
IV
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Problem 3: Disease Mortality. Harvest declines have been
compounded since 1986 due to extensive disease mortalities caused
by MSX (Haplosporidium nelsoni) and Dermo (Perkinsus marinus).
Little is known about how these diseases are transmitted, and they
cannot be controlled or eliminated. Current management actions
rely on favorable natural conditions to combat these diseases, and
are primarily reactionary in nature.
Strategy 3: Actions should involve increased monitoring of the
diseases so that timely decisions can be made regarding seed and
shell plantings. Additional research needs to be conducted on the
diseases and on disease-resistant oysters.
Problem 4: Leased ground production. Production from private
leased bottoms could enhance the Bay-wide oyster harvest, but
leased grounds are under-utilized. Expenses, shortage of seed and
shell, and disease mortality are among the contributing factors.
Strategy 4: There will be a Bay-wide effort to increase leased
ground production by increasing the amount of seed available,
developing new culture methods, continuing technical extension
services, and implementing "proof of use" measures.
Problem 5: Habitat Issues. Water and habitat quality impacts the
distribution and abundance of oysters.
Strategy 5: The objectives of the 1987 Chesapeake Bay Agreement
will be promoted.
Problem 6: Shellfish Sanitation. Many areas otherwise suitable
for shellfish production are closed or lost due to contamination
by pollutants and bacteria.
Strategy 6: Plans under the 1987 Chesapeake Bay Agreement to
improve water quality will be promoted, and depuration and relaying
methods will be investigated.
Problem 7: Market Production. Chesapeake Bay oysters are becoming
less competitive in the national market because of smaller Bay
harvests, standard quality and high price, and negative public
perception associated with oyster diseases and pollution.
Strategy 7: Enhancement of Bay-wide oyster stocks by following this
plan should improve many market considerations, and public
awareness programs can used to combat misperceptions about the
quality of Chesapeake Bay oysters.
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Problem 8: Repletion Programs. Current repletion programs are not
improving oyster stocks, and other problems are arising. Obtaining
an adequate supply of dredged shell for cultch is becoming
increasingly difficult, and the amount of fresh or house shell
available is declining as the harvest declines. Much of the fresh
shell is also being lost because of out-of-state exports and
distribution to many small businesses. Seed (small) oyster
production is decreasing because of oyster diseases, and
transporting shell and oysters to disease-free areas (often farther
up tributaries) is becoming more expensive.
Strategy 8: There needs to be a Bay-wide effort to distribute
shell and seed to reflect the best biological information
available. Recommended actions include reviewing statutes that
dictate repletion strategies, analyzing production as it relates
to seed and shell plantings, and evaluating export taxes on
oysters. Expanded seed programs, establishment of oyster
sanctuaries, a repletion program on the Seaside of Virginia, and
increased use of alternative sources of cultch are also necessary.
VI
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INTRODUCTION
MANAGEMENT PLAN BACKGROUND
To protect and manage the natural resources of Chesapeake Bay,
the jurisdictions are developing and will implement a series of
fishery management plans under the Chesapeake Bay Agreement. This
agreement adopted a schedule for the development of Bay-wide
fishery management plans for commercially, recreationally, and
selected ecologically valuable species. The strategy for
implementing the Living Resources Commitments in the 1987 Agreement
listed the priority of each species and a timetable for completion
of fishery management plans:
0 oysters, blue crabs and American shad by July 1989
0 striped bass, white perch, bluefish, weakfish, and spotted
trout by 1990
0 croaker, spot, summer flounder and American eel by 1991
0 red and black drum by 1992
A comprehensive approach to Bay problems and a means to
coordinate the various state and federal groups was also necessary.
Bay fisheries are managed separately by the States of Pennsylvania,
Maryland, and Virginia, the District of Columbia, and the Potomac
River Fisheries Commission. There is also a federal Mid-Atlantic
Fishery Management Council (MAFMC) which has jurisdiction for
management planning over offshore fisheries (3-200 miles), and a
coast-wide organization, the Atlantic States Marine Fisheries
Commission (ASMFC), which coordinates the preparation of plans for
migratory species in state coastal waters from Maine to Florida.
The state/federal Chesapeake Bay Stock Assessment Committee (CBSAC)
is responsible for developing a Bay-wide Stock Assessment Plan
which includes collection and analysis of fisheries information but
does not include the development of fishery management plans.
Consequently, a Bay-wide Fisheries Management group, under the
Living Resources Subcommittee of the Chesapeake Bay Program, was
formed to address the commitment in the Bay Agreement for
management plans.
The Fisheries Management group is responsible for developing
and writing the fishery management plans and includes:
Maryland Department of Natural Resources, Fisheries Division;
Pennsylvania Fish Commission, Office of Chief Counsel, Planning and
Environmental; Potomac River Fisheries Commission; Virginia
Marine Resources Commission, Fisheries Management Division; and
Washington, D.C. Department of Consumer and Regulatory Affairs,
Fisheries Management Division. The management workgroup also
included representatives from the Chesapeake Bay Foundation,
vii
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Chesapeake Bay Commission, University of Maryland, College of
William and Mary/Virginia Institute of Marine Science, Maryland
Watermen's Association, Virginia Watermen's Association, Charter
Boat Association, and Maryland Saltwater Sportsfishermen's
Association. Plans developed by this group reflect the
multijurisdictional management requirements appropriate to the
species.
WHAT IS A FISHERY MANAGEMENT PLAN?
A management plan is a dynamic process of analyzing the complex
biological, economic and social components of a particular finfish
or shellfish fishery, defining problems, identifying solutions, and
implementing decisions regarding habitat problems and human usage
of the resource.
GOALS AND OBJECTIVES FOR FISHERY MANAGEMENT PLANS
The goal of fisheries management is to protect the reproductive
capability of the resource and provide for optimal harvests.
Fisheries management must include biological, economic and
sociological considerations in order to be effective. It requires
an adaptive management scheme which responds to the most current
status of the stock, therefore, it is of primary importance to
prepare a plan which provides a means of regular review and
reevaluation of current management actions. Three simply stated
objectives to protect the reproductive capabilities of the resource
while allowing optimal harvest include:
° quantify biologically appropriate levels of harvest
° monitor current and future resource status to ensure harvest
levels are conserving the species while maintaining an
economically viable fishery, and
0 adjust resource status if necessary through management efforts.
MANAGEMENT PLAN FORMAT
The background section for each management plan summarizes:
0 biological profile
0 habitat requirements
° historical fishery trends
0 economic profile
Vlll
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° current stock status
0 current regulations (in effect as of September 1988), and
° data needs
This information was modified from the Chesapeake Bay Fisheries;
Status. Trends. Priorities and Data Needs document. Including this
section as part of the management plan provides historical
background and basic biological information for each of the
species.
The management section of the plan defines:
0 specific goals and objectives for each species
0 problem areas for each species
0 management strategies to address each problem area, and
o
action items with a schedule of implementation.
These plans are concise summaries that consider interjurisdictional
issues and recommend regulations which will be subject to public
review and appropriate approvals. Management planning provides the
opportunity for public and scientific evaluation, and debate of
management options and regulation strategies prior to actual
regulatory proposals. As the management plan review process
continues, changes will be necessary. The strategies will be
further defined as new information becomes available and,
therefore, must reflect some flexibility.
Once the plan has been adopted by the Executive Committee
appropriate regulatory and legislative action will be initiated.
An annual review of the management plans will be required to
continually update management strategies and actions. A workgroup
will be established to annually review the plan. Completed
management plans will follow the schedule set forth by the
Chesapeake Bay Agreement. The process of fishery management plan
review and acceptance is presented in the flow chart below.
ix
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COMMITMENT PREPARATION AND ADOPTION FLOW CHART
WORKGROUP
DRAFTS
DOCUMENT
DRAFT TO
I.C.
LIVING RESOURCES
SUBCOMMITTEE
REVIEW
CBLO DISTRIBUTES
TO CBP MAILING
LIST
CBLO DISTRIBUTES
TO LIBRARIES
PUBLIC MEETINGS
IF REQUIRED
30 DAY PUBLIC
COMMENT PERIOD
ADVISORY
COMMITTEE
BRIEFINGS
WORKGROUP
REVISES/PREPARES
SECOND DRAFT
LRSC REVIEWS
2ND DRAFT
SHORT SECOND
PUBLIC COMMENT
PERIOD
2ND DRAFT MAILED
TO P.S.C.
I.C. REVIEWS
RECOMMENDS
CHANGES/ADOPTS
2ND DRAFT MAILED
TO CBP MAILING
LIST, ETC.
FMP WORKGROUP
MAKES FINAL
REVISIONS
FINAL DRAFT
DISTRIBUTED TO
I.C.
1C (Implementation Committee)
CBLO (Chesapeake Bay Liaison Office)
CBP (Chesapeake Bay Program)
LRSC (Living Resources Subcommittee)
PSC (Principal Staff Commi
LRSC APPROVES
FINAL DRAFT
FINAL DRAFT
DISTRIBUTED TO
P.S.C.
EXECUTIVE
COMMITTEE
ADOPTION
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SECTION 1. BACKGROUND
American oyster Introduction
American oysters occur along the east coast of North America from
the Gulf of St. Lawrence, Canada, to Key Biscayne, Florida. In the
Carribean, the range of American oysters extends to the Yucatan
Peninsula of Mexico and the West Indies of Venezuela. Chesapeake
Bay, which provides optimal environmental conditions for the
species, is close to the center of its geographical distribution.
However, oyster production varies within the Bay system depending
on habitat conditions.
Oysters generally spawn from May through September in Chesapeake
Bay. Larvae settle to the bottom two to three weeks after hatching
and attach to oyster shells or other hard substrates. The attach-
ing phase is termed "setting" and the newly attached oysters are
called "spat." Oysters grow at the rate of about one inch per year
and enter the market from three to five years after spat
settlement.
Oysters have a unigue ecological role in the estuarine environment.
As a result of their reproduction, growth and tremendous filtering
capacity, the oyster bar community is radically different from
surrounding sand and mud communities. Oysters can filter and remove
sediments and algae from the water column.
FMP Status and Management Unit
The 1987 Chesapeake Bay Agreement contains a commitment to develop,
adopt and begin to implement a Bay-wide FMP for oysters by July
1989.
The management unit is the American oyster (Crassostrea virqinica)
throughout its range in the Chesapeake Bay.
Fishery Parameters
Status of exploitation: Fully exploited.
Long term potential catch: Currently unknown, highly dependent
on prevalence and intensity of
diseases.
Importance of recreational
fishery: Insignificant.
Importance of commercial
fishery: Highly significant; although
harvests are declining, oysters still
rank as one of the top seafood
species in dockside value.
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Fishing mortality rates:
Biological Parameters
Natural mortality rate:
Fecundity:
Longevity;
Age/size at maturity;
In the late 1970's, estimated at
0.24. Probably much higher now
Not quantified, but variable.
Mortality may be high under
conditions of disease, hypoxia or
high freshwater inflow.
5 - 15 million eggs at one spawning.
Generally 5-6 years; up to 15 years.
2-3 years/3 inches.
Habitat Requirements
Spawning and larval development
Spawning season: May through September.
Spawning area: Throughout Chesapeake Bay.
Salinity:
Temperature:
pH:
Dissolved oxygen:
7-30 ppt; at 5 ppt, gametogenesis is
retarded.
68° - 75° F.
o • o ~~ o • o •
Survival minimum 2.4 ppm.
Subadults and Adults
Location:
Salinity:
Temperature:
Dissolved oxygen:
Habitat Issues
Semi-hard mud to hard, rocky
substrate.
5-32 ppt.
60° - 86° F.
Survival minimum of 2.4 ppm.
Some of the more important environmental factors affecting oyster
stocks include substrate type, depth, salinity, and disease
prevalence. Oysters need a clean, stable substrate on which to set
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and grow. Soft mud, shifting sand or silted bottom are unsuitable.
Oysters are generally limited to waters less than 25' deep due to
hypoxic/anoxic conditions that develop in many deeper waters of
the Bay. Salinities above about 12 ppt increase oyster mortality
from predation and disease.
Man's activities have impacted the distribution and abundance of
oysters. Sediment from channel dredging, upland construction and
agricultural activities can smother oyster beds and foul cultch to
prevent setting. Nitrogen and phosphorus enrichment from sewage
treatment plants and agricultural runoff have increased the extent
of hypoxic and anoxic conditions. Sewage input results in high
coliform bacterial counts which force the closure of shellfish
harvesting areas close to the treatment outfall. In 1986 only
45,500 out of 158,900 acres in the James River were classified by
the National Shellfish Sanitation Program as approved shellfish
growing waters. Maryland oyster samples collected and analyzed from
1980-1986 revealed that heavy metal or PCB concentrations were
below action levels in all oyster growing areas sampled in the
state. However, these oysters did have levels higher than would be
found in a pristine environment.
The Fisheries
Before the turn of the century, over 10 million bushels of oysters
(which yielded approximately 64 million pounds of meat) were
harvested annually in Maryland by a large dredge fleet. Virginia
harvests at this time were approximately 6-7 million bushels (38-
45 million pounds of meat), and were harvested primarily by hand
tongers. Landings have declined dramatically since that time and
continue to show a downward trend. During the past 27 years, oyster
harvests in Maryland ranged from 3.2 million bushels (20.4 million
pounds) in 1973 to 565,146 bushels (3.6 million pounds) in 1987
(Figure 1) . In Virginia, the harvest of market oysters over the
same time period ranged from 1.9 million bushels (12 million
pounds) in 1964 to 442,000 bushels (2.8 million pounds) in 1987
(Figure 2) . Prospects for the near future are for similarly low
harvests.
Economic Perspective
In Maryland, oysters have always been a major part of the yearly
commercial fishery landings. On the average from 1971-1986, 48% of
the total dockside value and 21% of all commercial landings were
from oysters. In 1986, in addition to the dockside value of $17.47
million, harvesting and processing activities generated an
additional $25 million of output of all goods and services along
with $14 million in employee income and $1.84 million of indirect
taxes. Although the price per bushel of oysters increased in 1988
($20/bushel), the total dockside value for the Maryland oyster
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harvest decreased from 16.3 million dollars in 1987 to 7.3 million
dollars.
Total landings and dollar value, however, are not the best
indicators of the health of a fishery. Economists have developed
several indices related to profits which indicate the health of a
fishing industry. From an economic analysis of the Maryland fishing
industry, the 1987 productivity of the oyster industry has declined
to about 40% of the 1981 value. This loss has been tempered by a
decline in effort and an increase in the price of oysters. As a
result, watermen who continued to harvest oysters earned
approximately the same profits as they earned in 1981. According
to the Maryland fishing industry analysis, if oyster prices in 1987
had remained at the 1986 level, industry health and watermen
profits would have fallen to their lowest value in the decade.
Resource Status
At present, the Baywide oyster stock can be characterized as
severely depleted. Recent expansions of the range of oyster
diseases, MSX (Haplosporidium nelsoni) and Dermo (Perkinsus
marinus), low dissolved oxygen episodes and past harvesting
practices are primarily responsible for the population's current
decline. Average levels of spatfall have dropped in the past decade
and the number of natural beds receiving spatfall adequate for
replenishment has been reduced from historic levels. In Maryland,
the 1983 and 1984 spat sets were virtually non-existent. Although
the 1985 spatfall was exceptionally high and well distributed, the
year class has been effectively wiped out in those areas infected
by disease. Maryland's 1986 spatfall was considered average and of
limited distribution. Many of the 1986 year class have been
infected by MSX and Dermo and may be killed if high salinities
continue in the Maryland portion of the Bay. Continued low levels
and poor geographic distribution of spatfall levels have occurred
during 1987 and 1988.
Since 1985, the James River has become the center of the market
oyster landings in Virginia. The low number of surviving spat, as
determined from the VIMS oyster shoal surveys since the spring of
1986, indicates that the James River is failing to match the losses
in number of oysters with an equal recruitment of spat. Bushel
counts (spat, small, and market) for spring 1988 were below 100
oysters per bushel downriver from Wreck Shoal and Dry Shoal in the
James. Upriver of these same bars, the bushel count has dropped
from an average of 504 oysters per bushel in the spring of 1986 to
274 oysters per bushel in the spring of 1988. In the Great
Wicomico River, spat per bushel averaged 887 spat on all bars, but
the number of small oysters decreased 56 percent in one year.
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Current management strategies for oysters in Chesapeake Bay include
an annual planting of oyster shell on natural bars and the
transporting of seed oysters from areas of high spat set to areas
of low set.
Laws and Regulations
Limited entry:
Maryland's Delay of Application
Process went into effect September
1, 1988 and requires previously
unlicensed applicants to wait two
years after registering with MDNR
before a license to harvest oysters
with commercial gear will be issued.
On the Potomac River, only Maryland
and Virginia residents may
commercially oyster.
Limited or delayed entry are not in
effect in Virginia.
Minimum size limit:
Maryland - 3".
Potomac River- 3" with 5% tolerance,
however, market oysters with small
oysters attached must be returned if
separating them kills the small
oyster (including spat).
Virginia - James River Seed Area
market oysters must equal or exceed
2.5"; all other areas, 3". No cull
size for leased (private) grounds.
Daily catch limit:
Recreational — Maryland, Potomac
River and Virginia: no license
required for the taking of one bushel
per day from public grounds.
Commercial — Maryland: shaft and
patent tongs - 25 bushels per
licensee, but not to exceed 75
bushels per shaft tong boat or single
rig boat, or 100 bushels per double
rig boat; dredge boat - 150 bushels
per boat; diving - 30 bushels per
boat; power dredging (in designated
waters of Somerset county) - 12
bushels per licensee but not to
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Harvest quotas:
Season:
exceed 24 bushels per boat.
Commercial—Potomac River: None.
Commercial — Virginia: Hand tongs
15 bushels per person per day or 45
bushels per boat per day in the
Nansemond, Poquoson and Back Rivers
and Chisman Creek; patent tongs and
dredge-15 bushels per person per day
or 45 bushels per boat per day for
the Pocomoke Sound/Tangier Management
Area and 45 bushels per boat per day
for the Chesapeake Bay Management
Area.
Not in effect in Maryland, on the
Potomac River or Virginia.
Maryland - Shaft tongs, patent tongs
and diving; September 15 to March 31,
Monday through Saturday, sunrise to
sunset, except Worcester County where
the season is January 1 to December
31, Monday through Saturday, sunrise
to sunset. Dredging: Sail dredging
in designated waters state-wide,
November 1 to March 15, Monday
through Saturday, sunrise to sunset.
Power dredging; in designated waters
of Somerset County, November 1 to
March 15, Monday through Saturday,
sunrise to 3 pm. Private grounds: no
seasonal restrictions, but harvesting
between sunset and sunrise or on
Sunday is prohibited.
Potomac River - Hand shaft tongs:
October 1 through March 31. Hand
Scrape; Months of November, December
and March.
Virginia - Shaft tongs or hand tongs;
James River Seed Area, October 1 to
July 1, sunrise to sunset. All other
public areas, October 1 to June 1,
sunrise to sunset (except sunrise -
2 p.m. for Cod Harbor and Pocomoke
Sound, and sunrise to 12 noon for
Milford Haven). Private grounds, no
seasonal restrictions; but harvesting
on Sunday or between sunset and
8
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sunrise is prohibited.
Patent tonas: October 1 to March 1,
sunrise to sunset, for all public
areas not prohibited by Section
28.1-82 of the Code of Virginia or
VMRC Regulations and Orders. October
1 to the last day of February,
sunrise to 2p.m., in the Piankatank
River, Pocomoke Sound/Tangier and
Chesapeake Bay Management Areas.
Private grounds, Sunday and sunset
to sunrise harvesting is prohibited.
Dredge; Pocomoke/Tangier Management
Area, 15 November-last day of
February (sunrise-2 P.M.). Chesapeake
Bay Management Area, 1 November-last
day of February (sunrise-2 P.M.).
Private grounds, generally no
restrictions, except Sunday and
sunset to sunrise harvesting is
prohibited.
Gear Restrictions: Maryland - The legal gear types for
harvesting oysters in Maryland
include hand tongs, patent tongs,
diving gear, handscrapes and dredges.
The use of each gear type is
restricted to certain designated
areas as set forth in Maryland's laws
and regulations. Dredges or
handscrapes cannot exceed 200 Ibs.
in weight or have a tooth bar greater
than 42 inches in length (as measured
from the outside teeth) on dredges
used on rock bottom, or 44 inches in
length for dredges uses on mud
bottom. No "devil catch", "devil
diver", or similar device is to be
attached to the dredge to steer it
to the bottom. No power boat may have
on board or in tow any gear used for
dredging unless it is permitted by
the Department to harvest oysters
from leased bottom, from State seed
areas, or unless it is a sail dredge
boat using it's yawl boat on push
days. On Monday and Tuesday during
the oyster dredging season a dredge
boat may be propelled by an auxiliary
yawl boat in certain areas. Diving -
each person engaged in the diving
operation must be licensed. Not more
-------
than two divers can work from a boat
at one time. Each diver shall have
one attendant on the boat. An
International Code Flag "A" of the
proper specifications must be
displayed. Power assisted lifted
devices may be used subject to
specified conditions.
Potomac River - Patent tongs and
power or sail scrapes or dredges,
power or hand-operated winch, spool,
winder, ets. are prohibited. Hand
scrapes limited to 22" catching bar.
Diving for oysters limited to
recreational harvest of 1 bushel per
person per day. Legal gear types
include hand shaft tongs, power
assisted hand shaft tongs and hand
scrape.
Virginia - Only one type of gear,
either hand tongs, patent tongs
(limit of 2) or a single dredge, is
allowed on a vessel at one time in
the Pocomoke/Tangier and Chesapeake
Bay Management areas. Only one type
of gear, either hand tongs or patent
tongs (limit of 2), is allowed on a
vessel at one time in the Piankatank
River Management Area. Patent tongs -
the teeth of patent tongs shall not
exceed four inches in length, and
patent tongs exceeding 100 pounds in
gross weight, including any
attachments (excluding rope for the
taking or catching of oysters), are
prohibited. Dredge - a dredge and
attachment cannot exceed 100 pounds
total weight.
Area Restrictions: Maryland - Hand tongs are allowed
Statewide, with portions of most
tributaries reserved for hand tongs
only. Downstream of these areas,
diving is allowed. Patent tongs are
permitted in the mainstem Chesapeake
Bay, the lower Patuxent River and all
of Somerset County. Power dredging
is restricted to designated waters
of Somerset County. Sail dredging is
restricted to the Mainstem Bay,
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Time Restrictions:
Tangier Sound, and portions of the
Choptank River.
Potomac River - No harvest allowed
in 25 acre oyster sanctuary on Jones
Shore. Hand tongs, none except
sanctuary. Hand scrapes, not allowed
on Jones Shore or above a line from
Herring Creek, MD to Bonum Creek, VA.
Virginia - Only hand tongs are
permitted in most areas, with patent
tongs restricted to those areas
specified by the Code of Virginia or
VMRC Regulations and Orders
(Piankatank River, Chesapeake Bay and
Pocomoke/Tangier Management Areas).
Dredging is restricted to the
Pocomoke/Tangier and Chesapeake Bay
Management Areas.
Potomac River - Hand tongs, lawful
only Monday through Friday from
sunrise to 3:00 p.m. EST. Hand
scrapes, lawful only Monday through
Thursday during March and Monday,
Wednesdays and Fridays during
November and December from 8:00 a.m.
to 12 noon each day.
Status of Traditional Fishery Management Approaches
Catch-Effort:
Estimates of mortality:
Yield-per-Recruit:
Stock-Recruitment:
Maximum Sustainable
Yield (MSY):
Commercial fisheries data for
Chesapeake Bay are a reasonable
indicator of the current status of
the stock. However, catch and effort
statistics for the commercial fishery
are, in general, of low quality and
of limited value in developing
fisheries management models.
3-100% depending on disease
prevalence.
Currently unknown.
The stock-recruitment relationship
for Chesapeake Bay oysters is
unknown.
Perhaps as high as 14 million pounds
in Maryland under ideal conditions.
11
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Virtual Population
Analysis (VPA): Has not been carried out.
Data and Information Needs
1. Yearly evaluation of the geographic distribution and
prevalence of MSX and Perkinsus.
2. Evaluation of the ability of MSX resistant oysters to survive
when placed in the Chesapeake Bay.
3. Identification of the MSX mode of transmission and the
oyster's immune response to MSX.
4. Evaluation of production from seed plantings in low salinity
areas.
5. Determine factors affecting abundance, survival and growth of
larvae and juveniles.
6. Determine the acreage of actively cultivated leased bottom
and estimates of CPUE from that acreage.
7. Determine production potential for synthetic cultch material.
8. Determine the density of spawning stock necessary to
repopulate an area decimated by disease.
9. Determine natural and fishing mortality rates.
10. Define stock/recruitment relationship.
11. Identify costs associated with harvesting and processing
activities.
References
Haven, D.S., W.J. Hargis and P.C. Kendall. 1981. The oyster
industry of Virginia: its status, problems and promise. VIMS
Special Paper in Marine Science No. 4 1024.
Kennedy, V.S. and L. Breisch. 1981. Maryland's oysters: research
and management. Maryland Sea Grant, UM-SG-TS-8104, College Park
Md.
Lipton, D. 1987. The status of Maryland's fishing industry.
University of Maryland, Sea Grant Extension. Publ. No. UM-SG-MAP-
89-02.
12
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Maryland Department of Natural Resources. 1987. Maryland's oyster
resources: status and trends, 1987. MDNR, Tidal Fisheries Division,
Annapolis, Md.
Virginia Marine Resources Commission. 1988. Oyster resources in
Virginia, Part I: Description. VMRC Fisheries Management Division,
Newport News, Va.
13
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SECTION 2. OYSTER MANAGEMENT
The source documents for this plan (Haven et al., 1981; Kennedy and
Breisch, 1981; MD DNR, 1987; VMRC, 1988) discuss many problems
associated with the current status of the Chesapeake Bay oyster
resource and its industry. Oyster management programs in Maryland
and Virginia have consisted of protecting oyster bars from dredging
or filling, planting shell on natural oyster bars, transporting seed
oysters to augment natural oyster production, and regulating oyster
harvest through seasons, catch limits, cull laws, and gear
restrictions. With an increase in disease, the historical management
techniques are no longer cost effective and the regulations need to
be reevaluated. The Maryland and Virginia oyster resource is
characterized by instability and declining harvests and warrants
comprehensive management. For this plan, oyster problems have been
grouped into several categories which served as the basis for
identifying the goal and management objectives. The problems are
followed by strategies developed to address the oyster problems.
Current regulations regarding oyster harvest will continue to be
enforced with specific changes as recommended by the management plan.
Fishery activity on the tidewater portion of the Potomac River is
managed by the Potomac River Fisheries Commission, a six member body
empowered under the Maryland-Virginia Compact of 1958. The Commission
meets quarterly to establish and maintain a program of conservation
and improvement of the seafood resources and to regulate and license
fisheries in the Potomac River. The Commission will develop
appropriate Actions and Implementations to address those Problems and
Strategies identified in the Management Plan which are within the
purview of the Commission by July 1990.
A. GOAL AND OBJECTIVES
The overall goal of this plan is:
Increase the baywide stocks of oysters through the
initiation of short and long-term management actions which
will enhance the ecological value of the resource, ensure the
growth of the resource and maintain a viable fishery in the
long term. The management plan for oysters will be adaptive
and involve continuous responses to new information about the
current state of the resource.
In order to achieve this goal, the following objectives must be met:
1) Stabilize harvest to maintain a spawning stock at a size
which eliminates low reproductive potential as a cause of
poor spawning success.
15
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2) Promote protection of the resource by maintaining a clear
distinction between conservation goals and allocation
issues.
3) Evaluate statewide repletion efforts.
4) Encourage the utilization of aquaculture techniques on
private oyster grounds.
5) Develop quantities of low-cost, low-risk seed sources in
disease-free areas to benefit the public and private
industry.
6) Promote continued cooperation of various state agencies
in water quality and habitat improvement measures to
maximize conditions for natural production and to
minimize harvest restrictions due to sanitary reasons.
7) Further our understanding of oyster diseases and the
development of a disease-resistant strain of Chesapeake Bay
oyster.
8) Enable baywide fisheries management agencies to provide
more timely and effective responses to short term and
unpredictable changes in the status or operation of the
fishery.
9) Increase and stabilize the market share of Bay oysters by
providing a reliable product both in quality and quantity.
B. PROBLEM AREAS AMD MANAGEMENT STRATEGIES
Problem-Harvest Decline and Overharvesting: The Chesapeake Bay oyster
fishery can be characterized by instability and declining harvests.
During the past 27 years, oyster harvests in Maryland have ranged
from 3.2 million bushels (20.4 million pounds) in 1973 to 565,146
bushels (3.6 million pounds) in 1987. In Virginia, the harvest of
market oysters over the same time period ranged from 1.9 million
bushels (12 million pounds) in 1964 to 442,000 bushels (2.8 million
pounds) in 1987. A high mortality of market oysters during 1986 and
1987 have caused the resource to reach an all time low. Maryland's
1988 harvest of 355,473 bushels represents a 77% decline from the
1986 harvest of 1,557,091 bushels. Traditionally productive areas
have been lost due to disease mortality and the effects of advances
in gear technology. Presently, there is a concentrated fishing effort
up the tributaries and Bay to areas of about 12 parts per thousand
salinity or less. In Virginia this has resulted in the almost
exclusive use of the James River as the State clean cull area.
Similarly, the fishing effort in Maryland is directed on seed
plantings and the remaining naturally productive oyster bars.
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Strategy-Harvest Decline and Overharvesting: Oyster harvest from
public bars is governed by the quantity and distribution of natural
spat set. The outlook for future years is not promising and current
management attempts at increasing harvest on a local scale are
insufficient to halt the decline. The average catch per man day is
lower than the permitted daily limit, therefore, it is no longer an
effective means of conserving the oyster resource. Harvest levels
need to be set commensurate to the resource status. Analysis of
existing and future data on oysters will allow for necessary
modifications to the FMP strategies. Comprehensive use and
improvement of the FMP strategies is deemed necessary to revive the
fishery.
PROBLEM 1.1
Oyster harvest and associated revenues in the Chesapeake Bay
have declined to a record low. Current management practices
have not been effective in maintaining historical levels of
harvest.
STRATEGY 1.1
There will be a Baywide effort to stabilize oyster
harvest and protect brood stocks.
ACTION 1.1.1
Maryland and Virginia will open and close harvest
areas on a rotating basis to control fishing
effort. Recommendations for closed areas will
be based on an analysis of the oyster population
structure, i.e., number of adults, juvenile
oysters and spat, determined by annual surveys. As
an example, when adult oyster density reaches a
predetermined minimum, the bar will be closed.
IMPLEMENTATION 1.1.1
1990
ACTION 1.1.2
Maryland and Virginia will establish catch limits
that reflect the status of the resource. Catch
limits will be developed to stabilize harvest
based on historic harvest trends for specific
geographic areas. Recommendations will also consider
recent spat set, mortality rates, levels of disease
infection and growth rates.
IMPLEMENTATION 1.1.2
1991
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ACTION 1.1.3
Maryland will continue a delayed entry program to
stabilize fishing effort.
IMPLEMENTATION 1.1.3
Maryland law currently in effect.
Problem-Recruitment: For the past two decades, natural spat set has
been erratic and generally low. The geographic range of good setting
areas has also been reduced compared to historic trends. Though
there have been strong reproductive years such as 1985, the stocks
have been severely depressed by continued disease mortality, harvest
pressure, and water quality. The repletion programs in Maryland and
Virginia are dependent on natural spatfall.
Strategy-Recruitment: Both the magnitude of spat set and number of
consecutive years in which a spat set occurs in a specific geographic
area are important to future recruitment and harvest. Present
management efforts are dependent on natural spatfall. Planting shell
for the production of seed in seed areas provides more habitat for
new oysters.
PROBLEM 2.1
There has been a significant increase in the number of
specific oyster bars with low levels of spat set.
STRATEGY 2.1
There will be a Baywide effort to enhance natural
spatfall and recruitment to the fishery.
ACTION 2.1.1
Maryland and Virginia will continue hatchery
operations to produce eyed larvae and seed oysters
for research and rehabilitation projects.
IMPLEMENTATION 2.1.1
1989
ACTION 2.1.2
Maryland and Virginia will support aquaculture
efforts as a means of increasing oyster production
with a subsequent increase in brood stock.
IMPLEMENTATION 2.1.2
1990
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ACTION 2.1.3
Maryland and Virginia will continue the oyster
repletion program of planting shell for cultch and
moving seed oysters to augment natural reproduction.
IMPLEMENTATION 2.1.3
1989
ACTION 2.1.4
Maryland, as an experimental procedure, will
reconstruct buried oyster bars to the physical
configuration that enabled the extinct bar to be
productive in the past.
IMPLEMENTATION 2.1.4
1990
ACTION 2.1.5
Maryland and Virginia are conducting research on
the relationship between adult oyster density and
recruitment and will use the information to regulate
harvest and provide optimum stocking of seed
oysters.
IMPLEMENTATION 2.1.5
1992
Problem-Disease Mortality: Recent harvest declines, especially
during 1986 and 1987, are the result of extensive disease mortalities
by MSX and Dermo (Perkinsus). Virginia has lost most of their growing
areas due to disease. Little is known about the mode of transmission
of these diseases and there is no known cure. Presently, these
diseases cannot be controlled or eliminated.
Strategy-Disease Mortality: Recent expansion of the geographic
occurrence of oyster diseases has been one of the primary factors
contributing to the oyster decline in Maryland and Virginia. The
nature of the disease problem requires careful monitoring in order
to make timely decisions about management actions.
PROBLEM 3.1
The decline in the oyster resource has been compounded by
high mortalities from the diseases MSX and Dermo (Perkinsus)
in most of the commercially important oyster beds.
STRATEGY 3.1
There will be a Baywide effort to understand and control
the spread of oyster disease.
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ACTION 3.1.1
Maryland and Virginia will continue the annual
disease survey to determine the best plan for
planting seed and shell.
IMPLEMENTATION 3.1.1
1989
ACTION 3.1.2
Maryland will implement a program to monitor seed
oysters for disease before transporting to
disease-free areas. Techniques used for monitoring
will include histocytology, immunological detection
tests and histopathology.
IMPLEMENTATION 3.1.2
1990
ACTION 3.1.3
Maryland and Virginia will continue research on the
transmission and reduction of oyster diseases and
development of a disease-free strain of Crassostrea
virginica.
IMPLEMENTATION 3.1.3
1989
ACTION 3.1.4
Maryland and Virginia are researching the
development of a disease-resistant hybrid oyster
with the potential for introduction into the
Chesapeake Bay. Proper precautions will be taken
to avoid the introduction of exotic organisms
into the Bay ecosystem.
IMPLEMENTATION 3.1.4
1989
Problem-Leased Ground Production: Presently, private leased bottoms
are under-utilized. For both Maryland and Virginia it has been
estimated that less than 10% of the total leased grounds are in
production. The expenses of private bed preparation and seeding are
a deterrent and there is a shortage of shell and seed. Disease
mortality has also stifled private production and initiative.
20
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Strategy-Leased Ground Production: Private oyster production on
leased ground could enhance oyster harvest. During their best years,
Virginia increased oyster production by more than seven times from
their private leased grounds. In Maryland, leased bottom production,
especially in areas of low salinity, could provide increased
production.
PROBLEM 4.1
Leased ground is under-utilized and could be a viable means of
increasing oyster production.
STRATEGY 4.1
There will be a Baywide effort to increase leased ground
production as a means of conserving and enhancing the
oyster population in the Bay.
ACTION 4.1.1
Maryland has established a seed bed for sale of
seed to private leaseholders.
IMPLEMENTATION 4.1.1
1989
ACTION 4.1.2
Maryland and Virginia will continue an active
extension program to provide technical assistance to
oyster leaseholders.
IMPLEMENTATION 4.1.2
1989
ACTION 4.1.3
Maryland and Virginia will implement "proof of use"
measures in the form of minimum production or
repletion criteria, to promote private production
and cultivation.
IMPLEMENTATION 4.1.3
1990
ACTION 4.1.4
Virginia will promote the development of new culture
methods by removing impediments in the existing
permitting process required for the private sector.
IMPLEMENTATION 4.1.4
1990
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ACTION 4.1.5
Virginia will research the feasibility of and
methodology for new culture methods. VIMS will
initiate rack culture research by establishing pilot
studies. Results will be used to assess the economic
and biological feasibility of implementing such a
program in Virginia.
IMPLEMENTATION 4.1.5
1990
Problem-Habitat Issues: The distribution and abundance of oysters
are impacted by water quality. Nitrogen and phosphorus overenrichment
from sewage treatment plants and agricultural runoff have increased
the extent of hypoxic and anoxic conditions thus limiting oyster
distribution. Man's activities have also impacted the distribution
and abundance of oysters. Sediment from channel dredging, upland
construction and agricultural activities have smothered oyster beds
and fouled cultch enough to prevent setting.
Strategy-Habitat Issues: Water quality standards and strict
enforcement are necessary to insure adequate protection of living
resources in Chesapeake Bay.
PROBLEM 5.1
Water quality impacts the distribution and abundance of
oysters in Chesapeake Bay.
STRATEGY 5.1
Maryland and Virginia will promote the objectives of the
Chesapeake Bay Agreement to improve water quality in all
areas of the Bay.
ACTION 5.1
The following action items are commitments under the
1987 Chesapeake Bay Agreement. Maryland DNR and VMRC
will not carry out the specific commitments, but are
involved in setting the objectives of the programs
to fulfill the commitments and reviewing the results
of the action programs. The achievement of these
commitments will lead to improved water quality and
enhanced biological production.
A) Develop and adopt a basinwide plan that will
achieve a 40% reduction of nutrients entering the
Chesapeake Bay by the year 2000.
1) Construct public and private sewage facilities.
2) Reduce the discharge of untreated or
inadequately treated sewage.
3) Establish and enforce nutrient and conventional
pollutant limitations in regulated discharges.
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4) Reduce levels of nutrients and other
conventional pollutants in runoff from
agricultural and forested lands.
5) Reduce levels of nutrients and other
conventional pollutants in urban runoff.
B) Develop and adopt a basinwide plan for the
reduction and control of toxic materials entering
the Chesapeake Bay system from point and nonpoint
sources and from bottom sediments.
1) Reduce discharge of metals and organic
compounds from sewage treatment plants
receiving industrial wastewater.
2) Reduce the discharge of metals and organic
compounds from industrial sources.
3) Reduce levels of metals and organic compounds
in urban and agriculture runoff.
4) Reduce chlorine discharges to critical finfish
areas.
C) Develop and adopt a basinwide plan for the
management of conventional pollutants entering
the Chesapeake Bay from point and nonpoint
sources.
1) Manage sewage sludge, dredge spoil and
hazardous wastes.
2) Improve dissolved oxygen concentrations in the
Chesapeake Bay through the reduction of
nutrients from both point and nonpoint
sources.
3) Continue study of the impacts of acidic
conditions on water quality.
4) Manage groundwater to protect the water quality
of the Chesapeake Bay.
5) Manage marine sources of non-point pollution
such as recreational and commercial boat
dicharges.
6) Continue research to refine strategies to
reduce point and nonpoint sources of nutrient,
toxic and convential pollutants in the
Chesapeake Bay.
IMPLEMENTATION 5.1
Variable, depending on the specific project.
Problem-Shellfish Sanitation: In response to FDA guidelines,
Maryland's Department of the Environment established conditionally
approved areas which are restricted to shellfish harvesting for 3
days after periods of rainfall, 1" or more in a 24 hour period. This
was in response to a human health concern from consumption of oysters
contaminated with bacterial pathogens. The FDA guidelines keep
23
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oysters with transitory high levels of bacterial contaminants from
being harvested. The areas of concern are located in almost every
tributary in Maryland. For the 1987-1988 season there were
approximately 18 days when some part of the Bay was closed to
shellfish harvesting. Such closures interrupted harvest and market
supply but more importantly, the publicity about possible
contamination shifted consumer preference away from Maryland oysters.
In Virginia, continuous habitat degradation has resulted in
approximately 100,000 acres of productive or potentially productive
shellfish grounds being classified as unsuitable by the Division of
Shellfish Sanitation. Improvement or reopening of these areas will
be difficult because of high fecal coliform counts which cannot be
traced to point source pollution. This problem is expected to become
increasingly worse as human population continues to grow. In both
Maryland and Virginia, permitted discharges of treated wastewater
into the Bay and tributaries from sewage treatment plants require a
closed shellfish harvesting zone around the outfall. Construction or
expansion of sewage treatment plants to serve the growing population
or areas presently without public sewage connections, will increase
the number and size of outfall closures.
Strategy-Shellfish Sanitation: The sessile nature of oysters makes
them particularly vulnerable to adverse water quality conditions and
bacterial contamination. The oyster resource can be protected from
bacterial contamination by reducing the outflow of bacterially
contaminated water into shellfish harvesting areas. A less desirable
tactic is to move oysters from closed areas.
PROBLEM 6.1
Outfall from sewage is frequently the cause of bacterial
contamination of oyster bars in Chesapeake Bay.
STRATEGY 6.1
As an extension of the efforts to improve water quality
in the Bay through the nutrient, toxics and conventional
pollutant control plans of the 1987 Chesapeake Bay
Agreement, bacterial pollution will also be controlled.
ACTION 6.1.1
Maryland and Virginia will promote the objectives of
the Chesapeake Bay Agreement to improve water
quality in all areas of the Bay as stated in Action
5.1.
IMPLEMENTATION 6.1.1
Variable, depending on the specific project.
ACTION 6.1.2
Virginia will continue participation in the
Interagency Shellfish Enhancement Task Force
24
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(SENTAF) to encourage cleanup and opening of
condemned shellfish grounds.
IMPLEMENTATION 6.1.2
Currently being implemented
ACTION 6.1.3
A) Maryland and Virginia will investigate the
potential of depuration techniques. (1992)
B) Virginia will implement regulations allowing for
the containerized relaying of condemned oysters.
(1989)
IMPLEMENTATION 6.1.3
Variable, depending on the specific project.
ACTION 6.1.4
Maryland and Virginia will promote more effective
treatment of sewage through innovative disinfection
techniques and promote municipal water conservation
programs which should reduce sewage volume. Specific
items are defined in Action 5.1-A.
IMPLEMENTATION 6.1.4
1995
Problem-Market Production: Chesapeake Bay oysters are marginally
competitive in the national market because of their size, quality
and higher price. Consequently, consumer preference for Maryland
oysters has decreased and processors report that some restaurants
and seafood outlets have discontinued the sale of Maryland oysters.
Consumer avoidance to Maryland's oysters is also due to negative
media publicity about the diseases MSX and Dermo.
Strategy-Market Production: Application of optimum fishery
regulations, repletion programs, disease control and habitat
restoration should improve stock condition and result in larger
harvests and restoration of consumer confidence.
PROBLEM 7.1
The quality of Chesapeake Bay oysters has diminished and
consumer demand has been affected by the disease problem.
STRATEGY 7.1
There will be a Baywide effort to improve oyster
stock condition.
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ACTION 7.1.1
Maryland and Virginia will implement the strategies
of this management plan to restore oyster stocks.
Productive stocks should help correct the market
problems.
IMPLEMENTATION 7.1.1
1989
ACTION 7.1.2
A) Maryland will promote public awareness that
oysters infected with MSX and Dermo are safe to
consume.
B) Virginia will use industry and state promotion of
oyster quality to prevent further loss of market
production due to public misconceptions.
IMPLEMENTATION 7.1.1
1990
Repletion Program;
Maryland- In 1988, Maryland planted approximately 5.8 million
bushels of dredged shells; 130,000 bushels of fresh
shells; and 878,000 bushels of seed. Continued
funding is necessary to maintain this repletion
effort. The most immediate problem in the repletion
program is securing a supply of dredged shells to
meet future needs. The areas now being dredged will
last about two more years at best. Obtaining the
necessary permits to dredge new areas is increasingly
difficult with growing public pressure against any
expansion of the dredging program. No viable
substitutes exist for dredged shell.
As harvest declines, the amount of fresh shell
declines and Maryland loses 60% of its fresh shell
supply due to out-of-state export of the oyster
harvest. There is no economical nor logistical method
to purchase, transport and plant these shells back in
Maryland waters. The fresh shells that remain in
Maryland are a small contribution to the State's shell
needs.
The Department of Natural Resources has no disease-
free seed producing areas in Maryland. The
traditional seed grow-out areas are also infected
requiring expensive long distance transport of seed
to less impacted areas.
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Virginia- Repletion efforts have helped the oyster industry to
maintain production but only at low levels compared to
historical harvests. Further expansion of repletion
activities is needed to counteract disease problems,
water quality conditions, and climatic events. The
repletion program will need more than the 1.9 million
bushels of shell planted in 1987 to establish future
seed growing areas. Virginia has not developed its own
reef shell supply and receives only a small percentage
of the "house" shells from the packing and processing
industry. The number of seed areas have decreased due to
disease and have not improved. Additionally, the
repletion department does not have the necessary storage
areas, manpower or equipment to accommodate a large
volume of "house" shells. Virginia also faces a shortage
of disease-free seed growing areas for planting shells.
The problem is compounded because seed can no longer
be transplanted in historical grow-out areas in the
Potomac tributaries, lower Rappahannock River or
Pocomoke Sound because of disease intensity. The
repletion program must incur increased cost to
incorporate other less accessible grow-out areas.
The repletion program lacks adequate monitoring
equipment and manpower to quantitatively analyze
(stock assessment) the results of shell planting
and seed transplanting activities.
Strategy-Repletion Program: Planting dredged or fresh shell and seed
oysters will be the mainstay of the repletion program to supplement
natural oyster reproduction.
PROBLEM 8.1
The repletion program is adversely affected by low natural
spatfall, shortage of cultch, disease problems and cost of
transporting seed and shell.
STRATEGY 8.1
There will be a Baywide effort to distribute oyster shell
and seed to reflect the best biological information
available.
ACTION 8.1.1
Maryland will review the existing statutory
authority which dictates the distribution of
seed and shell.
IMPLEMENTATION 8.1.1
1991
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ACTION 8.1.2
Maryland will consider increasing the tax on
exported oysters to compensate for the loss of shell
and increase revenue for oyster propagation.
IMPLEMENTATION 8.1.2
1991
ACTION 8.1.3
Maryland and Virginia will evaluate their repletion
programs by monitoring production in the planted and
seeded areas.
IMPLEMENTATION 8.1.3
Currently being implemented.
ACTION 8.1.4
Maryland and Virginia will utilize alternative
sources of cultch.
IMPLEMENTATION 8.1.4
1989
ACTION 8.1.5
Maryland will continue to protect and expand
specific areas of oyster production by establishing
oyster sanctuaries for seed and research purposes.
IMPLEMENTATION 8.1.5
1991
ACTION 8.1.6
Virginia will enhance its seed oyster program in the
Great Wicomico, Piankatank, and James Rivers to
contribute to the rebuilding of the oyster fishery
in Virginia. Seed will be used to plant prime
disease-free growing areas.
IMPLEMENTATION 8.1.6
Currently being implemented
ACTION 8.1.7
Virginia will establish a special repletion program
for the Seaside of Eastern Shore.
IMPLEMENTATION 8.1.7
1989
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