Chesapeake Executive Council
                           903R91007
                     Chesapeake Bay
                     Atlantic Croaker
                     and Spot Fishery
                    Management Plan
                  greement Commitment Report
                                   1991
CB 00533
Chesapeake Bay Program
                                   i Printed on recycled paper

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                   Chesapeake Executive Council
           Chesapeake Bay
           Atlantic Croaker
           and Spot Fishery
         Management Plan
      Agreement Commitment Report
                        1991
Chesapeake Bay Program
                        i Printed on recycled paper

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                   Chesapeake Executive Council
           Chesapeake Bay
           Atlantic Croaker
           and Spot Fishery
         Management Plan
      Agreement Commitment Report
                        1991
Chesapeake Bay Program
                        i Printed an recycled paper

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                   Chesapeake Executive Council
           Chesapeake Bay
           Atlantic Croaker
           and Spot Fishery
         Management Plan
      Agreement Commitment Report
                         1991
Chesapeake Bay Program
                        I Printed on recycled paper

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        Chesapeake Bay
        Atlantic Croaker
        and Spot Fishery
       Management Plan
           Chesapeake Bay Program
     Agreement Commitment Report 1991
    Produced under contract to the U.S. Environmental Protection Agency
             Contract No. 68-WO-0043
Printed by the U.S. Environmental Protection Agency for the Chesapeake Bay Program

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                          ADOPTION STATEMENT
       We, the undersigned, adopt the Chesapeake Bay Atlantic Croaker and Spot Fishery Manage-
 ment Plan in partial fulfillment of Living Resources Commitment Number 4 of the 1987 Chesapeake
 Bay Agreement:

            ".   .   .  by July to develop, adopt, and begin to implement a Bay-
           wide management plan of oysters, blue crabs, and American Shad.
           Plans for the other major commercially, recreationally and ecologi-
           cally valuable species should be initiated by 1990."

       The Atlantic Croaker and Spot were designated valuable species in the Schedule for Developing
 Bay wide Resource Management Strategies. In 1991, the Atlantic Croaker and Spot plan was completed.

       We agree to accept the plan as a guide to managing the Atlantic Croaker and Spot stock in the
 Chesapeake Bay and its tributaries for optimum ecological, social and economic benefits. We further
 agree to work together to implement, by the dates set forth in the plan, management actions recommended
 to monitor the status of the stocks, obtain catch and effort information from the bait fishery, address
 research and monitoring needs, and develop the habitat and water quality criteria necessary for healthy
 Atlantic Croaker and Spot populations.

       We recognize the need to commit long-term, stable, financial support and human resources to the
 task of managing the Atlantic Croaker and Spot stock.  In addition, we direct the Living Resources
 Subcommittee to periodically review and update the plan and report on progress made in achieving the
 plan's management recommendations.
                                      Date  	December 18,1992

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 	  iii

EXECUTIVE SUMMARY 	   iv

INTRODUCTION	  vii

SECTION 1. Biological Background	    1
     Life History - Atlantic Croaker	    1
     Biological Profile - Atlantic Croaker	    2
     Life History - Spot	    3
     Biological Profile - Spot	    4
     The Fishery - Atlantic Croaker	    5
     Fishery Parameters - Atlantic Croaker	   10
     The Fishery - Spot	   10
     Fishery Parmeters - Spot	   13
     Economic Perspective	   13
     Habitat Issues	   17
     FMP Status and Management Unit	   17
     Resource Status - Atlantic Croaker	   18
     Resource Status - Spot	   18
     Laws and Regulations	   18
     Status of Traditional Fishery Management Approaches....   20
     Data and Analytical Needs	   23
     References	   23

SECTION 2. Atlantic Croaker and Spot Management	   27
     A. Goal and Objectives	   27
     B. Problem Areas and Management Strategies	   28
          1. Stock Status	   28
          2. Harvest of small Croaker and Spot	   29
          3 . Research and Monitoring Needs	   30
          4. Habitat and Water Quality Issues	   31


APPENDIX: Atlantic Croaker and Spot Implementation Matrix...   33


                             Figures

1.   Croaker commercial landings from the Atlantic coast....    6
2a.  Commercial landings for Atlantic Croaker from the
     Chesapeake Bay	    7
2b.  Maryland commercial landings for Atlantic Croaker	    7
2c.  Virginia commercial landings for Atlantic Croaker	    7
3.   Atlantic Croaker caught by recreational anglers,
     Mid-Atlantic	    9
4.   Spot commercial landings from the Atlantic Coast	   11
5a.  Commercial landings for spot from the Chesapeake Bay...   12
5b.  Maryland commercial landings for Spot	   12

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5c.   Virginia commercial landings for Spot	   12
6.   Spot caught by recreational anglers, Mid-Atlantic
     region	   14
7.   Spot caught by the commercial fishery,  Mid-Atlantic
     region	   14
8.   Maryland dockside value for croaker	   15
9.   Maryland dockside value for spot	   15
10.   Virginia dockside value for Atlantic croaker	   16
11.   Virginia dockside value for spot	   16
                                11

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                         ACKNOWLEDGEMENTS


     The Chesapeake Bay Atlantic Croaker and Spot Management Plan
was  developed under  the direction  of the  Fisheries Management
Workgroup.  Staff from the Maryland Department of Natural Resources
(MDNR),   Tidewater   Administration,   Fisheries   Division  were
responsible for  writing  the plan and  addressing  comments on the
draft versions.   Support was  provided  by staff from the Virginia
Marine Resources Commission (VMRC),  Fisheries Management Division.
Contributing MDNR staff  included Nancy Butowski and Harley Speir.
VMRC staff included David Boyd, Roy Insley, Sonya Knur, and Ellen
Smoller.  Thanks are due  to Verna Harrison  and Ed Christoffers for
guiding  the  plan through  the development and  adoption process.
Carin Bisland, from EPA's Chesapeake Bay Liaison Office, assisted
with production of title pages and fact sheets, and with printing
and  distribution.   Finally,  we  express gratitude to members of
other Chesapeake Bay  Program committees and workgroups and to the
public who commented  on the plan.


Members of the Fisheries Management Workgroup were:

Mr. Mark Bundy, STAC  Economic Advisory Group
Mr. K.A. Carpenter, Potomac River Fisheries Commission
Mr. Jeffrey S. Eutsler, Maryland Waterman
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
Ms. Linda Hurley, USFWS Bay Program
Mr. W. Pete Jensen, Chair,  MD Department of Natural Resources
Dr. Roman Jesien, Horn Point Environmental Lab
Mr. J. Claiborne Jones, Chesapeake Bay Commission
Dr. Ron Klauda, MDNR, Cheapeake Bay Research and Monitoring
Dr. Robert Lippson, NOAA/National Marine Fisheries Service
Dr. Charles F. Lovell, Jr., M.D., Virginia
Mr. Richard Novotny, Maryland Saltwater Sportfishermen's Assoc.
Mr. Ed O'Brien, MD Charter Boat Association
Mr. Ira Palmer, D.C.  Department of Consumer & Regulatory Affairs
Mr. James W. Sheffield, Atlantic Coast Conservation Assoc. of Va.
Mr. Larry Simns, MD Watermen's Association
Mr. Jack Travelstead, Virginia Marine Resources Commission
Ms. Mary Roe Walkup, Citizen's Advisory Committee
                               111

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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  baywide; fishery  management plans  (FMPs)  for
commercially,  recreationally, and  selected  ecologically valuable
species.  The  FMPs  are to be implemented by  the  Commonwealth of
Pennsylvania,   Commonwealth of  Virginia, District  of  Columbia,
Potomac  River Fisheries  Commission, and  State  of Maryland  as
appropriate.  Under a timetable adopted for completing management
plans for several  important species,  the Atlantic Croaker and Spot
FMP was scheduled for completion in December 1991.

     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.
The Chesapeake Bay Program's Living Resources Subcommittee formed
a Fisheries Management Workgroup to address the commitment in the
Bay Agreement for  comprehensive, baywide  fishery management plans.
The workgroup is composed of members  from government agencies, the
academic  community,  the  fishing   industry,  and  public  interest
groups   representing   the   District   of   Columbia,   Maryland,
Pennsylvania,  Virginia, and the federal government.


Development of Fishery Management Plans

     An FMP prepared under the 1987 Chesapeake Bay Agreement serves
as a framework for conserving and wisely using a fishery resource
of the Bay.  Each management plan contains a  summary  of the fishery
under consideration, a discussion  of  problems  and  issues that have
arisen, and recommended management actions.   An implementation plan
is included at the end of the FMP to  provide additional details on
the  actions that  participating jurisdictions will  take  and the
mechanisms  for taking these actions.

     Development of a fishery management plan is a dynamic process.
The  process starts  with  initial input by the Fishery Management
Workgroup,  is followed  by public and  scientific  review  of the
management  proposals,  and then  by  endorsement by the appropriate
Chesapeake  Bay  Program committees. A management  plan  is adopted
when  it  is signed  by  the Chesapeake  Bay  Program's  Executive
Committee.  In  some  cases, regulatory and legislative action will
have  to be initiated,  while in  others, additional  funding and
staffing may  be required to fully  implement a management action.
A periodic  review of each FMP is  conducted  under the auspices of
the Bay Program's  Living Resources Subcommittee, to incorporate new
information and to update management strategies as needed.
                                IV

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Goal of the Atlantic Croaker and Spot Management Plan

     The  goal  of  the  Chesapeake Bay  Atlantic Croaker  and Spot
Management Plan is to protect the croaker and spot resource  in the
Chesapeake  Bay,   its  tributaries,   and  coastal  waters,  while
providing the greatest long-term ecological, economic, and  social
benefits from their usage over time.

     In order to  meet  this goal, a number  of  objectives must be
met. These objectives are incorporated into the problem areas and
management strategies discussed below.


Problem Areas and Management Strategies

Problem 1: Stock  Status.   Recent commercial landings of Atlantic
croaker have been approximately  half  of  the historical landings.
Although effort data is lacking,  the decline in catch most  likely
represents a real  decrease  in  abundance.  Spot  landings have been
highly variable from year-to-year. Fluctuations in croaker and spot
landings  may be  related  to environmental  factors,  changes  in
fishing effort,  and the degradation  of estuarine habitats. Fishing
is generally directed at one year class and yield per recruit has
not been maximized.

Strategy  1:  Stock  Status.   The  jurisdictions will  continue  to
monitor the Atlantic croaker and  spot  populations  in the Bay and
cooperate with the Atlantic States Marine Fisheries Commission to
manage stocks along the coast.  Increases  in  yield per recruit will
be promoted.

Problem 2: Harvest of Small Croaker  and Spot. The magnitude  of the
scrap  catch,  incidental bycatch  and  discard mortality  of small
croaker and spot has not been determined  in  the Chesapeake Bay but
may significantly impact croaker and spot stocks.

Strategy 2: Harvest of Small Croaker and Spot.   The jurisdictions
will reduce the harvest of small croaker and spot in the directed
and non-directed fisheries by promoting bycatch reduction devices
(BRDs)  in  the  southern  shrimp  fishery  and   the   use  of fish
separators in the finfish trawl fishery. Each  jurisdiction will
continue its minimum mesh size restrictions for gill netting as a
means of reducing bycatch.

Problem 3: Research and Monitoring Needs:   There is a  lack of stock
assessment data  and socioeconomic information for both the Atlantic
croaker and  spot  stocks  in the Chesapeake  Bay  and along  the
Atlantic  coast.  Information  on  recruitment,  age,  size,  sex
composition,  and  migratory  patterns along  the  coast is  lacking.
Improved catch and effort data are needed  from the recreational and
commercial fisheries to assess the impact of fishing activities.

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Strategy 3: Research and Monitoring Needs. The jurisdictions will
promote research  on the biology  and socioeconomic  factors that
affect croaker and spot stocks in the Chesapeake Bay.

Problem 4: Habitat and Water Quality Issues. Atlantic croaker and
spot  are  dependent on  the Chesapeake  Bay for  nursery  grounds.
Habitat alterations within  the Bay affect  croaker and spot stocks.
Low dissolved oxygen limits their distribution through behavioral
avoidance  of  areas with stressful oxygen concentrations  and by
limiting their prey distribution.

Strategy  4 Habitat and Water Quality Issues:   The jurisdictions
will  continue  their efforts to improve water  quality  and define
habitat requirements  for  living  resources  in the  Bay.  Efforts
include identifying and controlling nutrients,  toxic  materials,
conventional  pollutants,   and  atmospheric  inputs;  protecting
wetlands and submerged aquatic vegetation;  and managing population
growth.
                                VI

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                           INTRODUCTION

MANAGEMENT PLAN BACKGROUND

     As part of the 1987 Chesapeake Bay Agreement's commitment to
protect and manage the natural resources of the Chesapeake Bay, the
Bay jurisdictions  are  developing a series  of fishery management
plans   covering   commercially,   recreationally,   and  selected
ecologically valuable species.   Under  the  agreement's Schedule for
Developing  Bayvide  Resource Management  Strategies,  a list  of
priority species was formulated,  with a timetable for completing
fishery management plans as  follows:

0  oysters,  blue crabs  and American  shad by July 1989;
°  striped  bass,  bluefish,  weakfish  and spotted seatrout by 1990;
0  croaker,  spot,  summer flounder and  American eel by 1991;
0  red and  black drum by 1992;  and
0  Spanish and king mackerel, tautog, black sea bass and freshwater
   catfish by 1993.

     A comprehensive and coordinated approach by the various local,
state and federal groups in the Chesapeake  Bay watershed is  central
to successful fishery management. Bay fisheries are traditionally
managed  separately  by  Pennsylvania,  Maryland,  Virginia,  the
District of Columbia, and the Potomac River Fisheries Commission.
There  is also a  federal Mid-Atlantic  Fishery Management Council,
which  has  management jurisdiction  for  offshore fisheries  (3-200
miles), and a coastwide organization,  the Atlantic States Marine
Fisheries Commission (ASMFC), which coordinates the management of
migratory  species  in state  waters  (internal  waters to 3 miles
offshore) from Maine to Florida. The state/federal Chesapeake Bay
Stock Assessment Committee (CBSAC) is  responsible for developing a
Baywide  Stock  Assessment Plan,  which includes  collection  and
analysis  of  fisheries   information,  but  does  not  include  the
development of fishery management plans.

     Consequently,  a Fisheries  Management Workgroup,  under  the
auspices  of  the   Chesapeake   Bay   Program's  Living  Resources
Subcommittee, was  formed  to address  the  commitment in the  Bay
Agreement  for baywide  fishery management  plans. The Fisheries
Management  Workgroup   is   responsible  for  developing   fishery
management plans with a broad-based  view.  The workgroup's members
represent  fishery  management  agencies  from  the  District  of
Columbia,  Maryland,  Pennsylvania,  the Potomac  River  Fisheries
Commission, Virginia, and the  federal government;   the Bay area
academic community; the fishing industry;  conservation groups; and
interested citizens. Establishing Chesapeake Bay FMPs, in addition
to coastal FMPs, creates a forum to specifically address problems
that are unique  to  the Chesapeake Bay.  They also serve as the basis
for implementing regulations in the Bay jurisdictions.
                               VII

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WHAT IS A FISHERY MANAGEMENT PLAN?

     A Chesapeake Bay fishery management plan provides a framework
for  the  Bay   jurisdictions  to   take  compatible,   coordinated
management measures to conserve and utilize a fishery resource.  A
management plan  includes  pertinent background  information, lists
management  actions  that  need  to  be taken,  the  jurisdictions
responsible for implementation, and an implementation timetable.

     A fishery management  plan is not an endpoint  in the management
of a  fishery;  rather, it is part of  a dynamic,  ongoing process
consisting of several steps. The first step consists of analyzing
the complex biological, economic and social aspects of a particular
finfish or shellfish fishery. The second step includes defining a
fishery's problems, identifying potential solutions,  and choosing
appropriate management strategies.  Next,  the chosen  management
strategies are put into action or implemented. Finally, a plan must
be regularly reviewed and updated in order to respond to the most
current information on the fishery; this requires  that a management
plan be adaptive and flexible.

GOALS AND OBJECTIVES FOR FISHERY MANAGEMENT PLANS

     The  goal   of  fisheries   management  is   to   protect  the
reproductive capability of  the resource while providing for its
optimal use by man. Fisheries management must include biological,
economic and social considerations in order to be effective. Three
simply stated objectives  to  achieve this goal are:

0    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

°    adjust  resource  use and   other  factors  affecting  resource
     status, as needed, through management efforts.

     These general objectives are incorporated with information on
a particular resource and  the current status of  management for that
resource, into specific objectives  for a fishery management plan.

MANAGEMENT PLAN FORMAT

     The background section  of this management plan summarizes:

0 life history and biological profile for each  species;

0 Atlantic croaker and spot  fisheries and fishery parameters;

°economic perspective;
                               Vlll

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° resource status;

°habitat issues;

° FMP status and management unit;

0 Current laws and  regulations in  the Chesapeake Bay;  and

0 data and analytical  needs.

     The  background  information  is  partially  derived  from the
document  entitled,  Chesapeake Bay  Fisheries;  Status.  Trends.
Priorities and Data Needs and is supplemented with additional data.
Inclusion of 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,  which   follows  the
background, defines:

°the goal and objectives  for management  of the  species;

°problem areas;

°management strategies to  address each problem  area;  and

° action items,  with a schedule for implementation,  by the
  appropriate management agency.

THE CHESAPEAKE BAY PROGRAM'S FISHERY MANAGEMENT PLANNING PROCESS

     The  planning  process  starts  with  initial  input  by  the
Fisheries Management  Workgroup and development  of a  draft plan.
This  is  followed by a review of  the  management proposals by Bay
Program committees, other scientists and resource managers, and the
public. After a revised draft management  plan is prepared, it must
be  endorsed  by  the  Chesapeake  Bay  Program's   Living Resources
Subcommittee  and Implementation and  Principal  Staff  committees.
The plan is then sent to the Executive Committee for adoption.

     Upon  adoption by  the  Executive Committee, the  appropriate
management  agencies implement  the plan.  In 1990,  the  Maryland
legislature approved §4-215 of the Natural  Resource Article giving
the Maryland Department of  Natural Resources  authority to regulate
a fishery once a FMP has been adopted by regulation.  In Virginia,
FMP recommendations are pursued either by  legislative changes or
through a public regulatory process conducted by the Commission. A
periodic  review  of  each   FMP is  conducted by  the  Fisheries
Management Workgroup to incorporate new information and to update
management strategies as needed.
                                IX

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                 Section l.  Biological Background

     The  Atlantic  croaker  (Micropoaonias  undulatus)   and  spot
 (Leiostomus  xanthurus)   belong  to  the  family  of  fishes called
Sciaenidae. Members  of  this family comprise an important inshore
bottom  fishery  resource along  the  Atlantic  coast  (Cowan  and
Birdsong 1985). The  croakers and drums characteristically produce
a  drumming sound  by vibrating their swim  bladder  with special
muscles.


Life History - Atlantic  Croaker

     The Atlantic  croaker can be  found along the coast  from Cape
Cod,  Massachusetts  to  Campeche  Bank,  Mexico  (Welsh  and Breder
1923) .  It is  one  of the  most  abundant  inshore  fish species,
especially in  the  southeast Atlantic and northern Gulf  of Mexico
 (Chittenden and  McEachran  1976).  Croaker  are also  known by the
common name, hardhead.  Differences in life history patterns have
been noted between croaker populations  found north  and south of
Cape  Hatteras, North  Carolina.  Generally,  northern populations
spawn earlier  in the season,  reach maturity later,  are  larger in
size,  and  live  longer  than  southern  populations   (White  and
Chittenden 1977) .  The differences between  populations have been
attributed to dissimilar temperature conditions  and not  to genetic
origin.

     Adult  croaker  generally  spend  the  spring  and  summer  in
estuaries and move offshore and south along the Atlantic coast in
the fall. In the Chesapeake Bay,  croaker migrate up-river and up-
bay in the spring,  randomly  move around during the summer, and then
swim  down-river  and down-bay in  the  fall  (Haven  1957).  Adult
croaker can be found in  the Bay  from March to October,  with peak
abundance  from May  through  August (Stagg  1986).  Mature croaker
spawn over shelf  waters during an extended fall-winter spawning
season. Fecundity, number of eggs per female, ranges from 100,800
to 1,742,000  eggs/female for fish 196 to 390 mm TL (7.7-15.4 inches
TL)  (Morse 1980) .  Size and  age  at  maturity vary  according  to
location.  Female  croaker   from  Chesapeake  Bay generally  reach
maturity at age III while 45% of male croaker reach maturity at age
II (Wallace 1940). Length at which 50% of the fish are mature has
been calculated by Morse (1980) and ranges from 185 mm TL to 233 mm
TL (7.3-9.2 inches TL).

     The  fall-winter  spawning   period  can begin  as   early  as
September and  continue  through  December. It occurs  over a broad
area and  includes  the mouth of the  Chesapeake  Bay  (Haven 1957).
Young-of-the-year croaker have been collected in coastal  estuaries
off the Virginia coast from October to February (Cowan and Birdsong
1985). They are known to move into  the York River in May  (Chao and
Musick 1977).  Juvenile  croaker  prefer low  salinity  habitats and

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open-water rather than submerged vegetation areas. Immature croaker
stay in  the Bay until  the water  temperature decreases  in  late
summer and fall, then migrate to coastal areas.

     Atlantic croaker are opportunistic bottom-feeders that consume
a variety of invertebrates and occasionally fish. They prefer muddy
bottoms and  generally  inhabit depths  less  than 120 m.  They are
considered a euryhaline species and have been collected coastwide
in salinities between  0  and 75 o/oo.  Adults  have  been collected
from water temperatures between  10°C  and 34°C (50-93°F). Maximum
life span  reported  for  croaker is 8  years.  Predators  of croaker
include striped bass, flounder, shark, spotted seatrout, croaker,
bluefish, and weakfish (Mercer 1987a).


Biological Profile - Atlantic Croaker

Natural mortality rate;       Estimates range from 39-63% a year.

Fecundity:                    100,800  to 1,742,000 eggs/fish  at
                              sizes  ranging  from  196-390 mm  TL
                               (7.7 -15.4" TL).

Longevity:                    7-8 years.

Age/size at maturity:         2-3 years;  males at  140-220  mm TL
                               (5.5-8.7"), females at 185-233 mm TL
                               (7.1-9.1" TL).

Spawning and Larval Development

Spawning season:              August  -  December  (north  of  Cape
                              Hatteras);  peak spawning occurs in
                              October.

Spawning area:                Cape  May,  New Jersey  to  Gulf  of
                              Mexico,  includes the mouth  of the
                              Chesapeake  Bay.

Location:                     25 to 265  feet  deep.

Salinity:                     30 ppt.

Dissolved  oxygen:             At least 5.0  ppm.


Young-of-Year

Location:                     Post-larvae  move  into   estuarine
                              waters  in late summer and early fall
                              where they  develop into  juveniles.

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Salinity:

Temperature:


Dissolved oxygen:

Subadults and Adults

Location:



Salinity:


Temperature:


Dissolved oxygen:
0-30 ppt.

Collected at 0-24°C (32-75°F) in the
upper Chesapeake Bay.

At least 5.0 ppm.
Shallow coastal and estuarine waters
in summer; deep, offshore waters in
fall.

Euryhaline, most frequently found in
5-30 ppt.

8-34°C  (46-93°F) on  the  Atlantic
Coast.

At least 5.0 ppm.
Life History - Spot

     Spot can be found along the coast and in estuarine waters from
the Gulf  of Maine to the Bay of  Campeche, Mexico. The  area of
greatest  abundance occurs from Chesapeake  Bay  to South Carolina
(Bigelow  and  Schroeder  1953) .  They have  been  collected from the
mainstem and all tributaries of the Chesapeake Bay and have one of
the most  extensive  distributions  of  any  marine-estuarine  fish
species in the Bay. Spot are considered one of the  major regulators
of benthic invertebrate communities in  the muddy,  shallow  (<10m or
32.5') zones  of the  Bay  (Homer  and Mihursky 1991). They are an
important  food source  for  other  species  in the  Bay.  Predators
include striped bass,  bluefish,   weakfish,  shark,  and flounder
(Mercer 1987b).

     Adult spot migrate into estuarine  areas in  the spring but are
not as widely distributed as young spot. They are generally found
in  the Chesapeake   Bay   from  April through October.  Spot  are
euryhaline and  salinity does not  appear  to affect distribution.
They are  tolerant of a wide range  of  temperatures and  have been
collected in waters from  1.2°C to 36.7°C  (34-98°F). Although they
can tolerate low temperatures, extended periods  of  low temperatures
can result in mortality.  They are relatively short-lived, with age
V fish a rarity. Ages 0 to II dominate the catch from populations
along the Atlantic coast (as cited by  Mercer  1987b) .  Spot reach
sexual maturity at age II and III.  Minimum size  at maturity ranges
from  186   to   214  mm  TL  (7.3-8.4")   (Mercer   1987b) .  Fecundity
estimates are available from a  small sample (n=2,  Dawson 1958) and
it is not known if they are representative of fully ripe fish.

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     When the water  temperature  starts to decrease  in  the fall,
adult spot move offshore to spawn. The spawning season extends from
late fall to early spring.  Spawning  occurs  over  a broad area and
data indicate that they use  areas further offshore and  in deeper
waters  than other  sciaenids  (Mercer 1987b).   Larvae move  into
estuarine areas as early as December. In the Chesapeake Bay,  spot
larvae have been collected during January and February (Welsh and
Breder 1923).  Low salinity areas  of bays and tidal creeks comprise
the primary nursery habitat for spot.  They are also associated with
eelgrass communities (Orth and Heck 1980).

     Young-of-the-year spot  generally reside in  tidal creeks and
shallow,  estuarine  areas  during the  summer.   When  the  water
temperature begins to  decrease  in the fall they move  to deeper
estuarine waters or the ocean. There is some  evidence that juvenile
spot overwinter  in Chesapeake Bay in deep  water (Mercer 1987b).
Juvenile spot are similar to adults in their ability to tolerate a
wide range of salinities and temperatures.

     Like croaker, spot are opportunistic bottom  feeders that eat
polychaetes,  crustaceans,  mollusks,  and detritus  (as  cited  by
Mercer 1987) .  Although both spot  and  croaker have similar diet and
habitat, a life history study in the  York River  Estuary, Virginia
concluded that they are able to coexist without directly competing
with one another because of spatial and temporal  differences  (Chao
and Musick 1977).
Biological Profile - Spot

Natural mortality rate:

Fecundity;
Longevity;

Age/size at maturity;
Currently unknown.

Only limited  data available (n=2).
Mature  females  produce  at  least
70,000 - 90,000 eggs.

4-5 years.

On the Atlantic  Coast,  spot mature
at the end  of their second year or
early in their third year at 186-214
mm TL (7.3-8.4") .
Spawning and Larval Development
Spawning season:


Spawning area:

Spawning location:
Spawning off  Chesapeake Bay occurs
from late fall to early spring.

Offshore coastal areas.

Spawning    occurs    more   heavily
offshore (78-384')  than inshore  (44-
60') .

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Salinity:

Dissolved oxygen:

Youna-of-the-year

Location:
Salinity:

Temperature:

Dissolved oxygen:

Subadults and Adults

Location:


Salinity:

Temperature:




Dissolved oxygen:
At least 20 ppt.

> 2.0 ppm.
Low  salinity  Bay waters  and tidal
marsh creeks with mud and detrital
bottoms; young-of-the-year are also
associated  with eelgrass beds  in
Chesapeake Bay.

0-30 ppt.

1.2- 358C  (34-95°F).

> 2.0 ppm.
Mud  and sandy  bottoms  in  inshore
waters; offshore to at least 40'.

0-30 ppt.

1.2- 35°C (34-95°F). Mortalities due
to prolonged cold  spells have been
observed in the Maryland portion of
the Chesapeake Bay.

> 2.0 ppm.
The Fishery - Atlantic Croaker

     Commercial  landings  of Atlantic  croaker from  the Atlantic
coast show a period of record high landings during the 1940's of 65
million pounds  (Figure  1) . By  the early  1950's,  the commercial
catch had decreased to less than 10 million pounds but was followed
by a moderate increase.  A  record low commercial catch of 1 million
pounds was recorded in 1970. There was a moderate peak in 1978 of
30 million pounds but over the last 10 years, croaker  landings have
declined to approximately  10 million pounds. The 1990  landings were
6.7 million pounds with the majority of  the catch from the South
Atlantic, particularly North Carolina.

     Commercial  landings   for  croaker  from  the Chesapeake  Bay
declined dramatically from almost 60 million pounds  in the 1940's
to  approximately 2 million pounds  in  the  1980's  (Figure  2a) .
Historically, the Chesapeake region accounted for the majority of
Atlantic Coast commercial croaker landings. Maryland landings
reached a high of 6 million pounds in 1942 but have ranged from

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1.06 million pounds  (1976) to 500 pounds over the last twenty years
(Figure 2b). Virginia landings have been as high as 55 million
pounds (1937) but in the last  few years have averaged 2.38 million
pounds  (Figure  2c) .  In  1990,  the  Chesapeake region  harvested
196,000 pounds.  Without  effort  information from  fisheries within
the  Bay,  it  is  difficult  to determine  how changes  in  fishing
practices and  market  demands  have  influenced commercial landings
and, therefore, abundance trends.  Despite the lack of effort data
from the Bay fisheries, the decline in catch most likely represents
a real  decrease  in abundance.  Catch-per-unit-effort  (CPUE)  data
from the North Carolina  winter  trawl surveys indicate decreasing
trends in catch.  The North Carolina fisheries have also observed an
increase in the proportion of small unmarketable fish (<225 mm or
9")  in the last  few years.

     Since  croaker  are  considered  a southern species,  landings
north of Chesapeake  Bay occur only when the population abundance is
high or under particularly favorable environmental conditions. It
has been  suggested  that periods  of high  landings  and northward
range  extension  are associated  with  warming trends  and  mild
winters;  cold winters reduce  recruitment  (Norcross 1983). Croaker
are caught  by a variety  of gear  types usually in  mixed species
fisheries. The average size caught differs by gear type. Generally,
fish are smaller in trawl catches  (less than  or equal to 200 mm TL
or 7.9") and larger from pound nets  (greater than or equal to 210
mm TL  or  8.3")  (Chittenden et al.  1990).  In the  Chesapeake Bay,
croaker are  caught  from spring (early April)  through early fall
(mid-October) primarily by pound nets.

     Croaker are considered an  important  recreational species in
the Chesapeake Bay.  They usually rank within  the  top 10 species
caught.  Maryland recreational  catches   in  1979   and  1980  were
estimated at  1.07 million  pounds  and 18,150 pounds, respectively
(Williams et al.  1984, Williams  et al 1983). Virginia recreational
catches  in  1985 and 1986 were  5.5  and  3.06  million  pounds,
respectively.  Recreational  landings from  the mid-Atlantic region
estimated by the Marine Recreational Fisheries Statistical Survey
(MRFSS) peaked in 1986 but have been declining (Figure 3) .  In 1990,
the downward trend  in recreational  catch  continued.

     In addition to  the commercial and recreational catch of market
size  croaker,  small croaker are  regularly  caught  in  several
commercial fisheries. As an example, croaker with a mean weight of
0.144 kg  (0.32 Ibs  or 5 oz.)  comprised 41.5% by weight and 34% by
number of the total  marketable fish  in the North Carolina long haul
seine catches  during  the 1989 season. Croaker of similar  size and
weight  are  caught by flynets. Scrap  fish (part of  the catch not
marketed for human  consumption but  sold for bait, industrial use,
or  discarded), comprised between  2% and 53% (average-28%) of the
North  Carolina flynet catch between October 1985  and April 1988.
Scrap catch also occurs in the pound net and trawl fisheries. There

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is a sizeable bycatch and discard mortality of small croaker from
the southern  shrimp fishery.  Scrap  catch,  bycatch,  and discard
mortality  significantly impact  the  croaker  population  (Mercer
1987a).   The magnitude  of  these  impacts on  the  Chesapeake  Bay
population has not been fully investigated.

Fishery Parameters - Atlantic Croaker

Status of exploitation:       Unknown, but likely near capacity.

Long term potential catch:     Currently unknown.

Importance of recreational    Significant in Virginia, currently
fishery:                      of variable importance in Maryland.

Importance of commercial      Historically significant.
fishery:

Total annual mortality:       Estimated at 68% a year based on an
                              analysis of the northern stock.


The Fishery - Spot

     Commercial landings for spot from both the Atlantic coast and
the  Chesapeake  Bay exhibit  year-to-year  fluctuations  with  no
apparent long-term trends (Figures 4 and 5a).  Yearly fluctuations
in harvest  can be  attributed to  the  general life history of spot
and  annual  environmental  differences  on  the   spawning  grounds
(Joseph 1972). Spot is a short-lived  species and  in most years the
commercial  catch  consists  of a single year class. Other factors
such  as   fishing   effort,   habitat   degradation,   and  economic
conditions also contribute to the annual fluctuations in commercial
landings  (Mercer 1987b). Before  1960,  the Chesapeake  and South
Atlantic  regions harvested  almost equal amounts  of spot.  South
Atlantic landings currently account for the  largest portion of the
total Atlantic  coast harvest. For  1990,  a total  of 6.4 million
pounds were landed from the Atlantic  coast with 4.6 million pounds
coming  from the  South  Atlantic,  1.7  million from the Chesapeake,
and the remainder  from  other mid-Atlantic areas.

     Within  the  Chesapeake  Bay,  the commercial harvest  of spot
usually begins during April or May and continues  until September or
October.  The  largest commercial  catches are reported during fall
when spot are migrating out of the Bay and most spot  are landed as
bycatch  from  the pound net  fishery  in the lower  Bay (Homer and
Mihursky  1991). In Maryland,  commercial catches have been as large
as 590,000  pounds  (late 1950s) but in recent years have been less
than  100,000  pounds   (Figure  5b).   Landings   in  Virginia  have
historically  been  an  order  of  magnitude  higher  than  those  in
Maryland. Spot catches  in Virginia have been as  high as 8 million
pounds  (1949) and  have  generally declined since  then  (Figure 5c).

                                10

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     The recreational catch from the Atlantic coast has fluctuated
between  12.5  million  fish and  31.4  million  fish   (5.0  to 13.3
million pounds)  since  1979.  For 1990,  the  recreational  catch of
spot  was 18.9  million  fish  (15.6 million came  from  the mid-
Atlantic). Of the 18.9 million caught,  11.3 million  fish were
harvested.  The  recreational  catch of  spot from the Chesapeake
region (in pounds)  has  exceeded  the commercial  catch  from the same
area except for  1989  (Figure 6 and 7).  In Maryland, spot are  one of
the species most frequently caught  by  recreational fishermen. Spot
ranked  third in a  1980  recreational  fishing  survey  with  an
estimated catch of more  than  1.3 million fish. In Virginia, spot
are generally larger, more abundant, and targeted by recreational
anglers.  Spot ranked first in  pounds landed  in  1985  (3 million
pounds)  and  fifth   in   1986  (1.6  million pounds).  In  numbers
harvested, spot  ranked  first  in 1985  (11 million)  and  second in
1986  (8.3 million).

     Similar to  croaker,  small  spot are caught  for  scrap in the
pound  net,  trawl,  and  long  haul  seine fisheries.  There  is  a
sizeable  bycatch and discard  mortality of  small spot  from the
southern  shrimp  fishery,  long haul seine and  the  flynet (a high
profile or high-rise  type of trawl)  catch. As an example, about 95%
of spot caught  in the North Carolina  flynet fishery between 1982
and 1988 were less than  marketable size (<  195mm or 7.7"). Scrap
catch, bycatch,  and discard mortality significantly impact the spot
population (Mercer 1987b).

Fishery Parameters - Spot

Status of exploitation:       Currently unknown.

Long term potential catch:    Currently unknown.

Importance of recreational    Highly significant in Maryland and
fishery:                      Virginia

Importance of commercial      Highly significant in Virginia with
fishery:                      landings  at  least   an  order  of
                              magnitude greater than Maryland.

Fishing mortality rates:      Currently unknown.

Economic Perspective - Atlantic Croaker and Spot

     Croaker and spot  are two  of  the  five sciaenid fishes that
account for about 18 percent of the landed value of all food fish
from the mid-Atlantic through the Gulf coast.  In Maryland, trends
in dockside  value  for croaker  and spot have  generally  followed
commercial landings  (Figure 8 and  9).  Despite  the variability in
commercial landings,  the  dockside  values  for croaker and spot in
Virginia have remained steady (Figure 10 and 11) . Since 1980, the
price per pound of croaker and spot in Virginia has increased.

                                13

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     Figure  6.  Spot caught  by Recreational
          Anglers,  Mid-Atlantic Region
    Million Pounds
   1979 1980  1981  1982 1983  1984 1985  1986 1987  1988 1989
                         Year
•1988 and 1989 numbers are preliminary


           Figure  7.  Spot caught  by the
     Commercial  fishery, Mid-Atlantic  Region
  3000


  2500


  2000


  1500


  1000


   500
      Thousand Pounds
    1979  1980 1981 1982  1983  1984 1985 1986  1987 1988 1989
                          Year
                       14

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    Figure 8. Maryland Dockside  Value for
                       Croaker
    Thousand pounds
                        Thousand $$
   1980  1981 1982  1983  1984 1985  1986 1987  1988  1989 1990
                          Year
                 Croaker $$
            Com. Landings
•1990 preliminary
    Figure 9.  Maryland Dockside  Value for
                         Spot
  140
     Thousand Pounds
                       Thousand $$
                                140
    1980 1981  1982 1983  1984 1985  1986 1987 1988  1989 1990
                          Year
•1990 preliminary
Spot $$   —G~ Com. Landings


       15

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    Figure  10. Virginia Dockside Value
             for Atlantic  Croaker
  Million pounds
                                 Million $$
 2
 0
 1960
1965
1990
           Commercial Landings
                      Dockside Value
     Figure 11. Virginia  Dockside  Value
                    for Spot
 Million pounds
                                 Million $$
1960
           Commercial Landings
                      Dockside Value
                                       1990
                        16

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     A socio-economic profile on croaker was completed in 1978 by
Austin et al. At this time the following conclusions were made: 1)
small croaker were a low value/high volume product and an expanded
market  could place  severe  pressure on  the  stocks unless  the
incidental catch of  croaker  were  reduced;  2)  food croaker  (large
croaker) are  of minor  importance  to fish  houses and there is a
substantial incidental  catch of small croaker that is discarded;
3) there is  a very  large  incidental  catch  of croaker associated
with the commercial shrimp fishery, estimated  at twice the size of
the total commercial catch of croaker, and 4) recreational fishing
will continue to expand.  Since  current information  is  lacking,
these areas of socio-economic importance need to be reevaluated.

     The value  of  spot  from the northeast region  (ME to VA)  has
been approximately 1 million dollars over the last few years.  The
1989 value was  $1,113,000  and  the   preliminary  1990 value  was
$878,000. Although the recreational catch of spot is significant,
its economic value along the coast and from the Chesapeake Bay has
not been estimated.

Habitat Issues - Atlantic Croaker and Spot

     Both croaker and spot utilize estuarine  and coastal oceanic
waters  at  various  life history  stages  and  times  of the  year.
Habitat alterations within estuarine  areas affect croaker and spot
stocks because they use these areas as nursery grounds.  Most
estuarine  areas  of the United States have been altered  to some
degree by such activities as agriculture drainage,  flood control,
development,  filling  of  shallow  water  habitat,  dredging  of
navigation channels,  and pollution. Federal and state programs have
been initiated to protect both coastal and estuarine waters.

     In addition to problems  caused by habitat  alteration, spot are
particularly sensitive to both chlorinated sewage effluent and to
residual chlorine in seawater.   In the 1970's, massive fish kills
estimated  at  5  -  10 million individuals  (spot, bluefish,  white
perch,  weakfish  and  menhaden)  were observed  in  the  James River,
Virginia adjacent  to two sewage treatment plants.  Low  dissolved
oxygen can affect croaker and spot distribution by limiting their
prey distribution. It can also limit their distribution by direct
avoidance of areas with stressful dissolved oxygen concentrations.

FMP Status and Management Units

     Atlantic croaker and  spot management plans were prepared under
the  Atlantic  States  Marine  Fisheries   Commission's   (ASMFC)
Interstate Fisheries Management Program  and completed  in October
1987. Management measures  for both species were reevaluated in 1990
by the ASMFC  scientific and  statistical  committee.  The  committee
emphasized the need to:  promote the development and use of bycatch
reduction devices (BRDs) through demonstration and application in
trawl fisheries; promote increases in yield per recruit by delaying

                               17

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entry to both the croaker and spot fisheries to ages greater than
one; and, implementation of research and monitoring projects. The
ASMFC plan  recommends a  coastwide  stock assessment  for croaker
within the next two years. The ASMFC's plans serve as the basis for
the Chesapeake Bay Atlantic croaker and spot FMPs.

     The management units are the Atlantic croaker, Micropoaonias
undulatus. and spot,  Leiostomus xanthurus. throughout their range
along  the Atlantic  coast  and  in  the  Chesapeake Bay  and  its
tributaries.

Resource Status- Atlantic Croaker

     Commercial landings  of Atlantic  croaker from the Chesapeake
Bay suggest that there has been a reduction in abundance. The most
recent  increase in  landings  along the  Atlantic  coast can  be
attributed to increases in North Carolina landings. An assessment
of North Carolina's winter trawl fishery indicates that the current
fishery is harvesting much smaller croaker than in previous years
(NCDNR 1990).  Catch-per-unit-of-effort (CPUE) data from the North
Carolina flynet catches cilso indicate a decline in catch from 1985-
86 to 1987-88.

     Based on  CPUE indices for juvenile Atlantic croaker from along
the coast,  annual  recruitment  is  highly variable. Maryland and
Virginia surveys indicate  high juvenile abundance in the mid-1970's
with another peak in  the early  1980's. The most likely explanation
for the  fluctuation  in abundance is  temperature.  Survey results
support  the  premise  that  year  class  strength  is  related  to
temperatures on the  nursery grounds  (Joseph  1972). There is also
strong  evidence to  suggest that  species  interaction,  such  as
predation on  young  croaker by  striped  bass, has  had a  negative
influence on croaker population levels (Dovel 1968).

Resource Status- Spot

     There  are no obvious trends  in abundance  of  spot  in the
Chesapeake  Bay  region  or from the  Atlantic  coast  based  on
commercial landings  data. Abundance estimates  are not available
based  on stock  assessment analysis.  Annual  variations can  be
attributed to variations  in  year class  strength, environmental
conditions, and fishing pressure.

Laws and Regulations

Limited entry;           Maryland's Delay of Application Process,
                         which went into effect September 1, 1989,
                         requires previously unlicensed applicants
                         to wait two years after registering with
                         MDNR before a license to harvest finfish
                         with  commercial fishing  gears will  be
                          issued.

                                18

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                         Virginia    -    Proposed    legislation
                         authorizing the  VMRC to  limit  or delay
                         entry to  fisheries  (House Bill  286)  was
                         introduced to the  1990  Virginia General
                         Assembly.  The   Bill  was   tabled  and
                         assigned  to  a  legislative  subcommittee
                         for further study.

                         Potomac River -  Current moratorium  on any
                         new commercial hook and line or gill net
                         licenses,  only  Maryland  and  Virginia
                         residents allowed to fish commercially.
Minimum size limit;

Atlantic Croaker-


Spot-


Creel limit:


Harvest quotas;


By-catch restrictions;

Season;

Gear - Area restrictions;
Maryland- 10" TL;  Potomac River-10" TL;
Virginia- None.

No   minimum  size   for   any  of   the
jurisdictions.

None in effect for  either  species for any
of the jurisdictions.

None in effect for  either  species for any
of the jurisdictions.

None in effect.

No closed season.
                         Maryland - purse seines, trawls, trammel
                         nets,   and    monof ilament   gill   net
                         prohibited.  (Otter  and beam  trawls are
                         legal on the Atlantic Coast at distances
                         of   one   mile   or   more   offshore).
                         Prohibition on gill  netting in most areas
                         of  Chesapeake  Bay  and  its tributaries,
                         except; (1) attended drift gill nets 2.5
                         to  3.5"  stretch  mesh  may  be  fished
                         outside the striped  bass spawning reaches
                         and; (2) anchor,  stake  and  drift gill net
                         4.0 to 6.0" stretch  mesh can be fished in
                         Chesapeake Bay, excluding the tributaries
                         south  of  Kent Point  from June  15  to
                         September 30, inclusive. Minimum stretch
                         mesh size  restrictions for pound  net -
                         1.5", haul seine - 2.5".

                         Potomac River - Current moratorium on any
                         new gill net or  hook and  line licenses.
                                19

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The use of a spear, gig, purse net, beam
trawl, otter  trawl,  or trammel  net are
prohibited.  Mesh  size  restrictions  on
pound net- 1.5", haul  seine- 1.5", fyke
net- 1.5", fish pot- 2.0", gill net 5.0"
with   a   maximum   of   7.0".   Length
limitations on pound net  (1200'),  stake
gill net  (600'),  anchor gill net (600' X
12'), fyke net (400'),  haul seine  (1200'
or  2400'),  fish  pot  (10').  Seasonal
restrictions:  Pound  net-  February  15
through December  15; Anchor or stake gill
net- June 1  through November  30;  Drift
gill  net-closed;  Haul  seine-January  1
through December  31 except Saturdays June
1  through August  31   and  Fridays  and
Saturdays September 1 through May 31.

Virginia   -    Trawling    prohibited   in
Virginia waters.   It is unlawful to set,
place  or  fish  a  fixed  fishing  device
within 300 yards of the  Chesapeake Bay
Bridge Tunnel.  From April I through May
31  the  spawning  areas  of  the  James,
Pamunkey,  Mattaponi,   and  Rappahannock
Rivers are closed to  stake  and  anchor
gill nets.

Minimum  stretch  mesh  size restrictions:
pound net 2";   gill net  2-7/8" (increased
to 3" in  1992) ;   haul seine 3" (nets over
200  yards long) . No haul seine can be
longer than 1000  yards or deeper than 40
meshes. Any gill  net not assigned a fixed
location,  shall  be  set  in  a  straight
line, have no greater  depth  than  330",
shall  not exceed  1200'  in  length,  and
shall be  fished  no closer than 200 feet
to any other  such gill net. Gill nets are
prohibited in the  Lower Hampton  Roads
area from the  Friday  preceding Memorial
Day  to Labor Day,  both days inclusive,
from 7:00 A.M.  to 5:00 P.M.;  gill nets
are  prohibited  in four  Eastern  Shore
Bayside  creek mouths  (the Gulf,  Hungars
Creek, Nassawadox  Creek and Occohannock
Creek) from June 1 to  October 31.  Also,
Sections  28.1-52  and 28.1-53 of the Code
of  Virginia  outline  placement,  total
length  and  distance  requirements  for
fishing structures.
       20

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Status of Traditional Fishery Management Approaches

The  following  definitions have  been  adapted from  the document,
"Status of the  Fishery Resources Off the Northeastern United States
for  1989"  (NOAA Technical Memorandum  NMFS-F/NEC-72).  For a more
thorough review of  fisheries  terminology,  refer to this document
under the section "Definition of Technical Terms."
Catch-Effort or Catch-Per-Unit-of-Effort;  Defined as the number or
weight of fish caught during  a  specific  unit of fishing time and
considered a basic measure of abundance or stock density.

Atlantic Croaker- Catch and effort  data  from both the commercial
and recreational fisheries in the Chesapeake Bay are insufficient
to  determine the  relationship  between  landings  and  abundance.
Although  trends  in  landings  do  not  necessarily  reflect  actual
abundance,  there  are  indications  that  croaker  abundance  has
declined. The CPUE  from the North Carolina  flynet catch declined
from 5,868 kg/catch in 1985-86 to 1,629 kg in 1987-88.

Spot-  Catch  and  effort  data  from  both  the  commercial  and
recreational fisheries in the Chesapeake  Bay are insufficient to
determine the  relationship  between landings  and abundance.  Spot
CPUE from the North  Carolina sciaenid-bluefish flynet catches have
fluctuated with no apparent trend. Mean seasonal  CPUEs ranged from
369 to  1,391 kg/trip,  with three-season  averages  of  788 kg/trip
(1982-85) and 817 kg/trip (1985-87).


Estimates of mortality: Instantaneous mortality  is defined as the
rate at which fish are removed from a population by death (Z). It
can be  represented  mathematically by the natural  logarithm  of a
ratio of the number of fish alive at the end  of a unit of time, to
the number alive at the beginning of the unit of  time. It can also
be expressed as a percentage of the population.

Atlantic Croaker- Total mortality rates are 37-60% when maximum age
is set between five and ten years, and mortality rates are 55-60%
(Z=1.15) for five or six year  life spans  (Chittenden et al. 1990).
A Z=1.15 is  appropriate for Chesapeake Bay fish which translates to
a 55-60% annual total mortality.

Spot- Mortality rates are unknown.


Yield-per-Recruit:  A mathematical calculation of the theoretical
yield that would be  obtained  from a year  class   (group of fish of
one age) if  they were harvested according to a certain exploitation
pattern over their life span.
                                21

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Atlantic Croaker- If instantaneous natural mortality (M) values are
between 0.5 and 1.0,  then calculated yield per recruit is between
32 and 91 g at an age at first capture of 1.5 years; and, between
25 and  125  g at an age  at  first capture of  3  years (Chittenden
1977) .

Spot- Since current mortality rates  are unknown, yield per recruit
analysis has not been calculated.


Spawning Stock  Biomass  (SSB)- The  total weight of  all  sexually
mature fish in the populcition. This changes depending on the size
of new  year classes,  the growth  rate of young fish, the  age at
sexual maturity, the growth  and  natural  mortality  of older fish,
and the fishing mortality rate:

Atlantic Croaker- Unknown.

Spot- Unknown.


Spawning Stock  Biomass  Per  Recruit  (SSBR)-  The  spawning stock
biomass divided by the  number of fish recruited to the stock at age
2. This number  is  in units of weight and measures  the average or
expected contribution of any one young fish to the spawning stock
biomass over its lifetime:

Atlantic Croaker- Unknown.

Spot- Unknown.


Stock-Recruitment;  The relationship between the adult stock size
and subsequent recruitment (fish that reach a certain size or age
in a specific year):

Atlantic Croaker-  Successful recruitment into the  Chesapeake Bay
and  survival  during  the  juvenile  stage is mainly determined by
environmental  factors.  Warm  winter  water  temperatures  allow
spawning to occur further north and contribute to a  higher survival
rate  of   overwintering  juveniles.  During   times  of  adverse
environmental conditions, the fishery becomes  heavily dependent on
North Carolina breeding stocks.

Spot-   A   first   approximation   of  a   Ricker   spawner-recruit
relationship has been examined by D. Bodolus,  VIMS. No significant
relationship between the two  could be discerned.  However,  from this
study the spawning population appears to  account for  approximately
10% of the variation in recruitment  of spot to the  Chesapeake Bay.
                                22

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Maximum Sustainable Yield;  The number or weight of fish in a stock
that can be taken by fishing without reducing the stock's biomass
or  reproductive  potential  from  year  to  year,  assuming  that
environmental conditions remain the same.

Atlantic Croaker- Unknown.

Spot- Unknown.


Virtual  Population Analysis;   Defined  as an  analysis of  fish
catches from a given year class over its life in the fishery.
Atlantic Croaker- Has not been carried out.

Spot- Has not been carried out.


Data and Analytical Needs- Atlantic Croaker

1.   Collect  information on  the biology and  population dynamics
     including data on growth, age structure, reproductive biology,
     migration patterns, mortality, long-term potential yield, and
     stock structure.

2.   Determine the  relationship between parental stock  size and
     environmental factors on year class strength.

3.   Improve  catch  and effort  data  for both the commercial and
     recreational croaker fisheries.

4.   Determine the  magnitude of incidental by-catch  and discard
     mortality of small croaker in non-directed  fisheries  in the
     Chesapeake Bay.

5.   Determine the  magnitude of the scrap/bait  catch  of croaker
     from the pound net, long haul seine,  and trawl  fisheries.


Data and Analytical Needs- Spot

1.   Determine the coastal  movement of spot and the extent of stock
     mixing.

2.   Collect biological data  including size and age composition of
     harvest, age at maturity, fecundity, and spawning periodicity.

3.   Improve catch and effort data.

4.   Determine  a  measure  of  annual   reproductive  success  and
     information on the relationship between  parental  stock size
     and environmental factors that regulate year class strength.


                                23

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References Cited

Austin, C.B., J.C. Davis, R.D.  Brugger,  and J.A.  Browder.   1978.
     Croaker  Workshop Report  and  Socio-Economic Profile.  NMFS
     Southeast Fisheries Center. Sea Grant Special Report No. 16.

Bigelow, H.B., and W.C. Schroeder.   1953.   Fishes of the Gulf of
     Maine. U.S. Fish. Wild. Serv.,  Fish. Bull. 53:423.

Chao, L.N., and J.A.  Musick.   1977.  Life history, feeding habits,
     and functional morphology of juvenile sciaenid fishes in the
     York River estuary,  Virginia.  Fish. Bull. 75:657-702.

Chittenden, M.E.,Jr., L.R.  Barbieri,  C.M.  Jones,  S.J.  Bobko, and
     D.E.  Kline.    1990.    Initial  information  on  the  Atlantic
     croaker, a final report on "Development of age determination
     methods,  life  history-population dynamics  information,  and
     evaluation  of  growth  overfishing  potential for important
     recreational fishes." Virginia  Institute  of Marine Science,
     Gloucester Point, Virginia.

Chittenden, M.E., Jr., and  J.D. McEachran.   1976.   Composition,
     ecology,  and  dynamics  of  demersal  fish  communities  on the
     northwestern Gulf of Mexico continental shelf, with a similar
     synopsis for the entire Gulf.  Tex.  A & M Univ., TAMU-SG-76-
     208. 104p.

Cowan, J.H.,Jr., and R.S.  Birdsong.   1985.   Seasonal occurrence of
     larval  and juvenile  fishes in  a  Virginia Atlantic  coast
     estuary with emphasis on drums (Family Sciaenidae).  Estuaries
     8(1):48-59.

Dovel,  W.L.    1968.    Predation by  striped bass as  a  possible
     influence on population size of the Atlantic  croaker.  Trans.
     Amer. Fish. Soc. 97:313-319.

Haven,  D.S.    1957.    Distribution,  growth and  availability of
     juvenile croaker, Micropogon undulatus,  in Virginia.  Ecology
     38:88-97.

Hildebrand,  S.F.,   and W.C.  Schroeder.     1928.  The  fishes  of
     Chesapeake Bay.  Bull.  U.S. Bur. Fish. 43(l):388p.

Homer, M.L.,  and  J.A. Mihursky.  1991.  Habitat  requirements for
     Chesapeake Bay living resources: Spot profile. Chesapeake Bay
     Research and Monitoring, 2nd Edition.

Joseph,  E.B.   1972.   The status of  the sciaenid stocks  of the
     middle Atlantic  coast.   Ches. Sci. 13:87-99.
                                24

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Mercer, L.P.  1987a.   Fishery management plan for Atlantic croaker
     (Micropoqonias undulatus).  Fish.  Rept.  No.  10 of the Atlantic
     States Marine Fisheries Commission. 90p.

Mercer, L.P.  1987b.   Fishery management plan for spot  (Leiostomus
     xanthurus).  Fish. Rept. No.  11 of the Atlantic States Marine
     Fisheries Commission. 81p.

Morse,  W.W.   1980.   Maturity, spawning  and fecundity of Atlantic
     croaker,  Micropogonias undulatus  occuring  north  of  Cape
     Hatteras, North  Carolina.  U.S.  Nat.  Mar.  Fish.  Serv. Fish.
     Bull.  (U.S.) 78(1):190-195.

Norcross,  B.L.    1983.    Climate  scale  environmental  factors
     affecting   year-class   fluctuations   of   Atlantic   croaker
     (Micropoqonias undulatus) in  the Chesapeake Bay.  Ph.D. diss.,
     Coll. William & Mary, Williamsburg, 387 p. +append.

North  Carolina  Department  of   Environment,  Health,  and  Natural
     Resources. 1990. Assessment of the North Carolina winter trawl
     fishery, Sept. 1982- Apr. 1985. Special Scientific Report No.
     53. Division of Marine Fisheries, Morehead City, N.C. 94p.

Orth, R.J.,  and  K.A.  Heck,  Jr.    1980.  Structural  components of
     eelgrass  (Zostera marina) meadows in the lower Chesapeake Bay
     fishes. Estuaries  3:278-288.

Stagg,  C.   1986.   An evaluation of  the  information available for
     managing   Chesapeake   Bay  fisheries:   Preliminary   stock
     assessments.  Vol.   II,  Atlantic  Croaker.   University  of
     Maryland, UMCEES[CBL] 85-29,  148p.

Wallace, D.H.  1940.  Sexual development  of  the croaker, Micropogon
     undulatus. and distribtuion of the early stages in Chesapeake
     Bay.  Trans. Am. Fish. Soc.  70:475-482.

Welsh,   W.W.,  and  C.M.  Breder.   1923.    Contributions  to  life
     histories of Sciaenidae of  eastern United States coast.  Bull.
     U.S. Bur. Fish. 39:141-201.

White,  M.L.,  and M.E.  Chittenden, Jr.   1977.   Age determination,
     reproduction and population dynamics of the Atlantic croaker,
     Micropoqonias undulatus.   U.S.  Nat.  Mar.  Fish.  Serv. Fish.
     Bull. 75:109-123.

Williams, J.B., T.P.  Smith,  H.J. Speir,  and S. Early.   1983.  1980
     Maryland  Saltwater Sportfishing  Survey.   Md.  DNR Tidewater
     Admin.  TA-CRD-83-1.

Williams, J.B., H.J.  Speir,  S. Early,  and T.P. Smith.   1982.  1979
     Maryland  Saltwater Sportfishing  Survey.   Md.  DNR Tidewater
     Admin.  TA-CRD-82-1.

                                25

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         Section 2. Atlantic Croaker and Spot Management

     The source  documents  for this plan, Atlantic  States Marine
Fisheries Commission Fishery Management  Plans for Atlantic Croaker
and Spot (Mercer  1987a and 1987b),  White  and Chittenden  (1976), and
Joseph  (1972)  contain current  knowledge  about stock  status and
research needs for Atlantic croaker and  spot in the Chesapeake Bay
and along the Atlantic coast. The following problems and management
strategies have been defined and serve as the basis for identifying
the goal and  objectives. The management strategies and actions will
be implemented by the jurisdictions to protect Atlantic croaker and
spot stocks in the Chesapeake Bay. Existing regulations regarding
the harvest  of these species will continue  to  be  enforced except
where otherwise indicated by the plan.

A. GOAL AND OBJECTIVES

The goal of this plan is to:

     Protect  the  Atlantic  croaker  and  spot  resource  in  the
     Chesapeake  Bay,  its  tributaries, and coastal  waters,  while
     providing the  greatest long term  ecological,  economic,  and
     social benefits from their usage over time.

In order to achieve  the goal, the following objectives must be met:

1)   Follow  the  guidelines  established by  the  Atlantic  States
     Marine Fisheries Commission  (ASMFC) for coastwide management
     of  the  Atlantic  croaker and  spot  stocks  and  make  Bay
     management actions compatible where possible.

2)   Maintain Atlantic croaker and spot  spawning stocks at a size
     which minimizes the  possibility of  recruitment  failure and
     determine the effects of environmental factors on year class
     strength.

3)   Promote harvesting practices which minimize waste and maximize
     the  biological  and  economic  return  from  the  resources
     especially in non-directed fisheries.

4)   Promote  studies to improve  the understanding of economic,
     social,   and   biological   aspects  of  the   commercial  and
     recreational fisheries.

5)   Continue to provide  guidance  for  the development  of  water
     quality  goals  and habitat protection  necessary  to protect
     Atlantic  croaker and  spot populations within  the  Bay  and
     coastal waters.
                                27

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B. PROBLEM AREAS AND MANAGEMENT STRATEGIES

Problem 1 - Stock Status:  The most recent peak in Atlantic croaker
landings occurred in 1977 and 1978  and were only about half of the
historical peaks.  Although effort data is lacking, the decline in
catch  most  likely  represents  a  real   decrease  in  abundance.
Fluctuations in croaker  landings and  decreasing  abundance may be
related  to changes  in  population structure,  the influence  of
environmental factors on the spawning grounds,  changes in fishing
effort, and the degradation of estuarine habitats.

     Spot  landings  have  been highly variable  from year-to-year.
These annual fluctuations have been attributed to spot's short life
span  and climatic  factors  on  the spawning grounds.  Increasing
fishing effort and habitat degradation  could lead to  declines in
spot abundance.

     Currently, croaker  and  spot are not reaching their maximum
potential in size before being harvested by the fishery.  Both are
migratory  species  along  the Atlantic  coast which  necessitates
cooperative  interstate  management  to   insure   that  they  are
adequately protected during all phases of their life history.

Strategy  1  -  Stock Status:   The jurisdictions will  continue to
monitor the Atlantic croaker and spot populations  in the Bay. Since
both  species  are  migratory,   interstate coordination  will  be
emphasized. Increases in yield per recruit will be promoted.

     Problem 1.1
     Annual abundance of  Atlantic croaker and spot  stocks  is highly
     dependent on  environmental conditions  during the  spawning
     season. Fishing generally affects one year  class and  yield per
     recruit has not been maximized in the fisheries.

          Strategy 1.l
          The  Bay  jurisdictions  will  continue   to  monitor  the
          Atlantic croaker and spot stocks and  cooperate with the
          Atlantic States Marine Fisheries Commission to manage the
          stocks through interjurisdictional  management measures.

               Action 1.1
               Maryland,  the  Potomac  River  Fisheries  Commission,
               and  Virginia  will  continue  to  participate  in
               scientific  and  technical meetings for  managing
               Atlantic croaker and spot along  the Atlantic coast
               and in estuarine waters.

                    Implementation 1.1
                    Continue
                                28

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          Strategy 1.2
          The jurisdictions  will  promote increases  in  yield per
          recruit for the Atlantic croaker and spot fisheries.

               Action 1.2.1
               A)  Maryland  and   the   Potomac  River  Fisheries
               Commission will  continue their 10  inch minimum size
               for Atlantic croaker.
               B) Virginia will implement a minimum size limit for
               Atlantic croaker if suggested by length-frequency
               analyses currently being conducted by the Virginia
               Institute of Marine Science (VIMS) and Old Dominion
               University (ODU).

                    Implementation 1.2.1
                    A) Continue  B) 1993

               Action 1.2.2
               The  jurisdictions  will  evaluate  the  need  for
               implementing a minimum size limit for spot.

                    Implementation 1.2.2
                    1992
Problem 2  -  Harvest of  Small  Croaker and Spot:   The incidental
bycatch and  discard  mortality  of small croaker  and  spot in non-
directed fisheries  such as the  southern  shrimp fishery and the
scrap catch  from pound  net, long haul seine,  and trawl  fisheries
are  substantial  and have  the  potential to  significantly impact
croaker and spot stocks.  The magnitude of bycatch in the Chesapeake
Bay  fisheries  and  the  impact   of   Atlantic  coast  bycatch  on
Chesapeake Bay populations have not been determined.

Strategy 2 - Harvest of  Small Croaker and Spot: The jurisdictions
will promote the use of trawl efficiency devices (TEDs) and bycatch
reduction devices (BRDs) and investigate other  means to reduce the
catch  of  small  croaker and  spot in non-directed and  directed
fisheries.

     Problem 2.1
     The magnitude  of  the scrap  catch,  incidental  bycatch and
     discard mortality  of  small  croaker  and  spot  has  not  been
     determined but  may significantly impact  croaker  and  spot
     stocks.

          Strategy 2.1
          The  jurisdictions will  reduce  the  harvest   of  small
          croaker  and  spot in   the  directed  and  non-directed
          fisheries.
                                29

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               Action 2.1.1
               A)  Through  the  ASMFC,  the  jurisdictions  will
               promote the development and use of trawl efficiency
               devices (TEDs) in the  southern  shrimp fishery and
               promote the use of bycatch reduction devices (BRDs)
               in the finfish trawl fishery.
               B)  Virginia  will  continue  its  prohibition  on
               trawling in  State  waters.  Virginia  will  maintain
               its 2-7/8" minimum mesh size for gill nets.
               C)  Maryland  will  continue  its  4-6"  gill  net
               restriction during June 15 through September 30 and
               implement a 3" minimum mesh size along the coast.
               D) The PRFC will continue  its  prohibition on gill
               net fishing during the summer.

                    Implementation 2.1.1
                    A) Continue  B)  Continue C) 1992  D)  Continue

               Action 2.1.2
               The jurisdictions will  investigate the magnitude of
               the  bycatch  problem  and  consider  implementing
               bycatch restrictions for the non-directed fisheries
               in the Bay.

                    Implementation 2.1.2
                    1992
Problem 3 - Research and Monitoring Needs: There is a lack of stock
assessment data for both the Atlantic  croaker and spot stocks in
the Chesapeake Bay. Information on recruitment, age,  size and sex
composition of the stocks  and how  they  vary with time and space is
needed. Assessing the migratory patterns and  the  extent of stock
mixing  for  both  croaker  and  spot  are  integral  factors  in
determining   appropriate   coastal   management  recommendations.
Improved catch and effort data are needed from  the recreational and
commercial fisheries to assess  the impact of fishing activities on
the croaker and spot  stocks. The socioeconomic profile on Atlantic
croaker  should be updated  and a  socioeconomic profile  on spot
should be undertaken.

Strategy 3 - Research and Monitoring Needs:   In order to identify
necessary  management  measures, a program of research  and data
collection will be pursued for Atlantic croaker and spot.

     Problem 3.1
     There  is  a  lack of stock assessment data and socioeconomic
     information for both the Atlantic croaker and spot stocks in
     the Chesapeake Bay and along the Atlantic coast.
                                30

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          Strategy 3.l
          The jurisdictions will promote  research on the biology
          and socioeconomic  factors  that affect  the croaker and
          spot stocks in the Chesapeake Bay. Research topics that
          need  consideration  include:  the effects of  coastal
          fishing on croaker  and spot abundance  in  the  Bay; the
          determination  of  migratory patterns   through  tagging
          studies;  the   monitoring   of  long-term   changes  in
          abundance; the size  and age structure of croaker and spot
          populations  within the  Bay;  and monitoring  juvenile
          abundance to  establish a reliable index  of year-class
          strength.

               Action 3.1
               The  Virginia  Marine Resources  Commission's  stock
               assessment  program  will  continue  to  analyze size
               and  sex  data  from  Atlantic  croaker  and  spot
               collected from the Virginia commercial fisheries.

                    Implementation 3.1
                    Continue

               Action 3.2
               A)  Maryland   and   the  Potomac  River  Fisheries
               Commission will encourage research to collect data
               on croaker  and spot biology, especially estimates
               of   population   abundance,    recruitment,    and
               reproductive biology.
               B)  Virginia  will  continue  to   fund  its  stock
               assessment  research conducted  by  VIMS  and  ODU,
               specifically  designed  to  provide  estimates  of
               population abundance,  recruitment,  and reproductive
               biology.

                    Implementation 3.2
                    A)  Continue      B)  Continue


Problem 4 - Habitat and Water Quality Issues:  Adult spawning and
larval distribution along the continental shelf, and juvenile over-
wintering within  the Chesapeake  Bay have been identified  as key
periods of environmental vulnerability. Habitat alterations within
the Bay  damage  croaker  and  spot  stocks  since they are used  as
nursery grounds. Low dissolved oxygen can affect croaker and spot
distribution by limiting their prey distribution. It also affects
their  distribution through  behavioral  avoidance of areas  with
stressful dissolved oxygen concentrations.


Strategy 4 - Habitat and Water Quality Issues:   The jurisdictions
will continue their efforts  to improve water  quality and  define
habitat requirements for the living resources  in Chesapeake Bay.

                               31

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Problem 4.1
Habitat alteration and water quality impact the distribution
and abundance of finfish species in the Chesapeake Bay.

     Strategy 4.1
     The  District  of  Columbia,  Environmental  Protection
     Agency,  Maryland,  Pennsylvania,   the  Potomac  River
     Fisheries  Commission,  and  Virginia  will continue  to
     promote  the commitments  of  the  1987 Chesapeake  Bay
     Agreement. The achievement  of  the  Bay commitments will
     lead to  improved  water quality and enhanced biological
     production.

          Action 4.1
          The  jurisdictions  will continue to  set  specific
          objectives  for  water quality  goals  and  review
          management  programs  established under  the  1987
          Chesapeake   Bay   Agreement.   The  Agreement  and
          documents developed pursuant to the Agreement call
          for:

          A)   Developing  habitat  requirements  and  water
               quality goals for various finfish species.
          B)   Developing  and  adopting basinwide  nutrient
               reduction strategies.
          C)   Developing and  adopting basinwide plans  for
               the reduction and control of toxic substances.
          D)   Developing and  adopting  basinwide management
               measures for conventional pollutants entering
               the Bay from point and nonpoint sources.
          E)   Quantifying the  impacts and  identifying  the
               sources  of  atmospheric  inputs on  the  Bay
               system.
          F)   Developing management strategies to  protect
               and  restore  wetlands  and  submerged  aquatic
               vegetation.
          G)   Managing population growth to minimize adverse
               impacts to the Bay environment.

               Implementation 4.1
               Continue
                           32

-------
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