903R94021
CBP/TRS 122/94
 December 1994
            Chesapeake Bay
           and Atlantic Coast
            Horseshoe Crab
      Fishery Management Plan
TD
225
.C54
H673
                              U.S. Environmental Protection Agency
                              Fujon III !r formation Resource
                              Center (JPM52)
                              ?M Chestnut St-cet
                              Phcociobiiio, PA 19107
          Agreement Commitment Report 1994
          Chesapeake Bay Program
  Printed on
Recycled Paper

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Regional Center foi  Environmental Information
            US EPA Region III
               11,50 Arch St.
           Philadelphia, PA 19103

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Chesapeake Bay and Atlantic Coast
             Horseshoe Crab
      Fishery Management Plan
          Agreement Commitment Report
                                   U S. Eiwisoamental Protection Agency
                                   Region HI Information Resource
                                   Certsr (3PM52)
                                   841 Chestnut Street
                                   Philadelphia, PA 19107
                  October 1994
             Edited By Nancy H. Butowski
 Printed by the U.S. Environmental Protection Agency for the Chesapeake Bay Program

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                             Adoption Statement
       We, the undersigned, adopt the 1994 Chesapeake Bay and Atlantic Coast Horseshoe
Crab Fishery Management Plan, as a continuing effort to fulfill the Living Resources
Commitment of the 1987 Chesapeake Bay Agreement.

       We agree to accept the Horseshoe Crab Plan as a guide to protecting the resource in the
Chesapeake Bay and Atlantic Coast, insuring its continued role in the ecology of coastal
ecosystems, and providing for its commercial, recreational and medical usage over time  We
further agree to work together to implement, by the dates set forth in the Plan, the management
actions recommended to address its ecological value, stock status, the fishery, and habitat
considerations.

       We recognize the need for long-term, stable financial support and human resources for the
task of enhancing the horseshoe crab resource. In addition, we direct the Living Resources
Subcommittee to review and update the Horseshoe Crab Plan  yearly and to prepare an annual
report addressing the progress made in achieving the Plan's management recommendations
Signatures
For the Commonwealth of Virginia
For the State of Maryland
For the Commonwealth of Pennsylvania
For the United Slates of America
For the District of Columbia
For the Chesapeake Bay Commission

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                        TABLE OF CONTENTS



LIST OF TABLES AND FIGURES	   i

ACKNOWLEDGEMENTS 	  ii

EXECUTIVE SUMMARY	'	iii

THE FISHERY MANAGEMENT PLAN PROCESS 	  iv

SECTION 1. BIOLOGICAL BACKGROUND 	   1
     Biological Profile	   4
     The Fishery	   5
     Habitat Issues 	  11
     Stock Status	  12
     Current Laws and Regulations	  12
     References	  14

SECTION 2. HORSESHOE CRAB MANAGEMENT  	  16
     Goal and Objectives	  16
     Ecological Value 	  16
     Stock Status	  18
     The Fishery	  18
     The Habitat	  19
     Implementation Matrix  	  21
                         LIST OF FIGURES
1. Horseshoe crab landings from the NE Atlantic region,
   1962-1992 	   7
2. Dockside value of horseshoe crabs from the NE region,
   1962-1992 	   8
3. Maryland commercial horseshoe crab landings and dockside
   value 	   9
4. Virginia commercial horseshoe crab landings and dockside
   value 	  10

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                         ACKNOWLEDGEMENTS

     The Chesapeake Bay  and Atlantic Coast Horseshoe Crab  Fishery
Management Plan was developed under the direction of the Fisheries
Management Plan  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).  Thanks are due to
members of the Living Resources Subcommittee, the Virginia  Finfish
Subcommittee, and to the public who reviewed and commented on the
plan.


Members of the Fisheries Management Workgroup were:

Mr. K.A. Carpenter, Potomac River Fisheries Commission
Mr. James O. Drummond, Maryland citizen representative
Mr. William Goldsborough, Chesapeake Bay Foundation
Dr. Edward Houde, UMCEES/Chesapeake Biological Laboratory
Mr. W.  Pete Jensen, Chair, Maryland Department of  Natural Resources
Dr. R. Jesien, Horn Point Environmental Lab
Dr. Ron Klauda, MDNR, Chesapeake Bay Research and Monitoring
Ms. Anne Lange, NOAA Chesapeake Bay Office
Mr. Richard Novotny, Maryland Saltwater Sportfishermen's Assoc.
Mr. Ed O'Brien, Maryland Charter Boat Association
Mr. Ira Palmer,  D.C.  Department of Consumer and Regulatory  Affairs
Dr. Carl N.  Shuster, Jr., Virginia Institute of  Marine Science
Mr. Larry Simns, Maryland Watermen's Association
Ms. Benjie Lynn Swan, Limuli Laboratories
Mr. Jack Travelstead, Virginia Marine Resources  Commission
Ms. Mary Roe Walkup, Citizen's Advisory Committee
Col. Franklin I. Wood, MDNR Natural Resources Police


Staff to the Fisheries Management Workgroup were:

Ms. Nancy Butowski, MDNR
Mr. James Casey, MDNR
Ms. Sonya Davis, VMRC
Mr. Lewis Gillingham, VMRC
Mr. Roy Insley,  VMRC
Mr. Thomas O'Connell, MDNR
Ms. Ellen Smoller, VMRC
Mr. Harley Speir, MDNR
Mr. Alan Weishe, MDNR

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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. The  original FMP  development schedule was amended to
include  horseshoe  crabs  with a  completion  date  of   1994.  The
Horseshoe Crab   FMP  was  drafted  by  staff  from  the  Maryland
Department  of  Natural  Resources  (MDNR)  with  support from  the
Virginia  Marine Resources  Commission (VMRC) staff. A FMP workgroup
consisting  of  members   from  government agencies,  the  academic
community, the fishing industry and public interest groups reviewed
and commented on  the  plan. The management plan contains a summary
of the  fishery  under consideration,  a discussion  of problems and
issues that have  arisen,  and recommended management actions.

Goal and  Objectives

The goal  of the Horseshoe Crab Fishery Management Plan is:

     Protect the horseshoe crab resource in the Chesapeake Bay and Atlantic Coast to insure
     its continued role in the ecology of coastal ecosystems, while providing the opportunity
     for commercial,  recreational and medical usage over time.

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

Areas of  Concern  and  Management Strategies

Ecological Value: Horseshoe crabs  play an  important ecological role
in the food web.  Adult horseshoe crabs are a major item in the diet
of juvenile loggerhead turtles. Several  shorebird  species rely on
horseshoe crab eggs to replenish  their fat supply  on their way to
Canadian  breeding  grounds.   Horseshoe   crab eggs   are  also  a
seasonally preferred food item of several  finfish species.  The
jurisdictions will protect the ecological role of  horseshoe crabs
by protecting horseshoe  crab  spawning areas and monitoring harvest.
The  hand  collection  of  horseshoe crabs from  beaches,  and  the
trawling,  scraping and dredging of crabs  from the Bay and within 1
mile of  the  coast,  will  be prohibited  in  Maryland  from  May  1
through June  7.  Virginia will prohibit the  hand collection  of
horseshoe crabs during the same time period and continue their ban
on trawling in state waters.
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Stock Status: The  present status of the horseshoe  crab stock is
unclear. The  stock was relatively stable between  1975  and 1983.
Neither  commercial exploitation nor  medical usage  have changed
significantly  over  the  last  9  years.  Recent  spawning  stock
estimates and fishery independent trawl data  from Delaware indicate
a drop in the number of horseshoe crabs. There is a need to obtain
better  information  on  horseshoe crab  population  dynamics.  The
jurisdictions will coordinate with Delaware  and develop a spawning
stock census in the Chesapeake Bay region which will serve as the
basis for determining management recommendations as appropriate.

The  Fishery:  Current   levels  of  commercial harvest  along  the
northeastern Atlantic coast are approximately 1.0 million pounds.
Horseshoe crabs are commercially harvested for use as eel, conch,
and catfish bait. Crabs are also used for medical research and bled
to  obtain  Limulus  amoebocyte  lysate,  a  clotting agent  used to
detect human pathogens  in drugs. Horseshoe crabs are vulnerable to
overfishing because of their  late  maturity  (9-11  years),  their
dependence  on coastal  and  bay  spawning  beaches,  the  selective
nature  of  the bait fishery for  egg-bearing females,  and  their
seasonally   abundant,    inshore   spawning   aggregations.    The
jurisdictions will  monitor the  commercial and medical harvest of
horseshoe crabs and  improve the quality of data obtained from the
commercial fishery.

The Habitat: Horseshoe  crabs  are generalists and  not as severely
restricted  by environmental  conditions  as  many other  aquatic
species. Protected beach areas are essential habitat for horseshoe
crab spawning. Activities which impact spawning areas will have a
negative impact on  the horseshoe crab population. The jurisdictions
will define and protect horseshoe cr.ab spawning areas, and work to
define water quality requirements.
                                IV

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THE FISHERY MANAGEMENT PLAN PROCESS

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,
management strategies, recommended actions, and an implementation
date.

     A fishery management plan is not an endpoint in the management
of a fishery but part of  a  dynamic, changing 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 the concerns
of  a  fishery,  identifying potential solutions,  and  choosing
appropriate management strategies. Once specific goals have been
defined, it is  important to measure  progress  towards  meeting the
goals, establish accountability and engage the general public.
Plans must be adaptive and flexible to meet the changing needs of
a particular resource. They are  annually  reviewed and updated in
order to respond to the most current information on the fishery.

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 developed  a series  of fishery management plans
for  commercially,   recreationally,   and   selected  ecologically
valuable species. A comprehensive and coordinated approach by the
various local,  state and  federal groups  in  the  Chesapeake Bay
watershed is  necessary  for 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  (MAFMC)  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.

     A Fisheries Management  Workgroup, under the auspices  of the
Chesapeake Bay Program's  Living Resources Subcommittee, was formed
to  develop  baywide  fishery  management  plans.  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


                                v

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that are unique to the Chesapeake Bay. They also serve as the basis
for implementing regulations in the Bay jurisdictions.

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.  Comments  are  incorporated  into   a  final draft of  the
management plan. It is  endorsed by  the Chesapeake Bay Program's
Living Resources Subcommittee (LRSC), the Implementation Committee
(1C) ,  and the Principal Staff Committee (PSC).  Finally,  the plan is
sent to the Executive Council (EC)  for adoption.

     Upon adoption by the EC, the appropriate management agencies
implement the plan. In 1990,  the  Maryland  legislature  approved
Section 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.

     The first group of fishery management plans was  completed in
1989.  Additional plans have been completed each year  encompassing
16 finfish and shellfish species. With time and  changes, it became
apparent that a substantive review of each  FMP at regular intervals
would be necessary.  The FMP workgroup developed a review schedule
to  upgrade  each plan  (Table 1) .  The  revised  FMP  must  be  sent
through the  regular Chesapeake Bay  Program's  fishery  management
planning  and  adoption  process.  Since  the major  review  schedule
extends over a 5-year period, important minor changes are addressed
through  an   amendment  procedure.   This   entails developing  a
description of the proposed changes and sending  it through the FMP
workgroup for endorsement.  The  amendment  must be published for
public  comment and reviewed  by the  LRSC and  the  1C for  their
comment and approval. The PSC has been given authority by the EC to
approve amendment changes.
                               VI

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Table 1. Schedule for reviewing fishery management plans
SPECIES
Shad/Herring
Blue Crab
Oysters
Striped Bass
Weakf ish/ Seatrout
Bluef ish
Croaker /Spot
American Eel
Summer Flounder
Black Drum
Red Drum
Catfish
Mackerel
Black Sea Bass
Tautog
Horseshoe Crabs
ADOPTION
DATE
1989
1989
1989
1989
1990
1990
1991
1991
1991
1993
1993
July 1995
1994
July 1995
December
1995
1994
REVIEW DATE
June 1995
1994
1994
August 1995
March 1996
June 1995
1996.
1996
March 1996
1997
2000
1998
2000
2000
1999
                               Vll

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Section 1. Biological Background

     Horseshoe crabs,  Limulus  polyphemus.  are benthic or bottom-
dwelling  organisms  that utilize  both estuarine  and continental
shelf habitats. The horseshoe crab belongs  to  the  largest group of
all  living  animals,  the phylum  known as  arthropods.  This group
includes  insects,  spiders,  scorpions  and  crabs.  Although  it is
called a  "crab,"  it  is not a true crab. Crabs  have two pairs of
antennae, a  pair  of mandibles or jaws,  and  five pairs of legs.
Horseshoe crabs lack  antennae and mandibles and have  seven pairs of
legs   (chelicera,   5  pairs  of  ambulatory/gustatory  legs,  and
chilaria). The presence of  chelicera  and book gills, and lack of
jaws and antennae  make horseshoe  crabs more similar  to spiders and
scorpions than to  "true"  crabs.  There are three  genera and four
species  which  comprise  the  living  members  of  the  subclass
Xiphosura. Of  these  living species,  Limulus  is  the only member
common to the northwestern Atlantic'coast and Gulf  of Mexico. All
the  other   members   (Tachypleus  tridentatus,   T.  gigas,  and
Carcinoscorpius rotundicauda)  are found along  the Asian coast from
Japan  and Korea  south through the East Indies  and Philippines.
Serological data from  three of the four  extant species indicates
they  are con-generic  (Shuster  1962).  Horseshoe  crabs are  the
closest   living  relatives  of   trilobites  and  their  external
appearance has  remained relatively unchanged over  the  last 360
million years.

     Limulus ranges from the Yucatan peninsula to northern Maine.
Each major estuary along the coast is believed to have a discrete
horseshoe crab population (Shuster 1979). These populations  can be
distinguished from one another by adult size,  carapace color, and
eye  pigmentation.  They  can  also  be  distinguished  by  their
serological responses  and through protein  electrophoresis  (Cohen
1979). Along the Atlantic coast, horseshoe  crabs are most abundant
between Virginia and  New Jersey with Delaware  Bay at the center of
the  species  distribution.   Within  Delaware  Bay,   the  largest
concentration of horseshoe  crabs  is found along the  Cape May shore
of New Jersey (Shuster and Botton 1985).  Although populations are
believed to be discrete from estuary to estuary, gene flow between
Delaware  Bay  and  Chesapeake Bay  populations  is  probable.  Adult
horseshoe crabs have been found as far as 56 kilometers offshore.
This distribution  pattern would allow an overlap between Delaware
and Chesapeake individuals.

     Horseshoe crabs  are well known for their highly  visible mating
activities.  Migrating adults move inshore from deep bay and coastal
waters in  late  spring to spawn.  Inshore movement  appears  to be
related to lengthening daylight hours. Spawning in the Chesapeake
and Delaware areas usually  begins during the latter part  of May
when large numbers of horseshoe crabs move onto beaches to mate and
lay eggs. The peak in spawning activity usually coincides with the
full moon and evening  spring  tides.  Adults  prefer beach  areas

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within bays and coves which are protected from surf. Spawning areas
are limited by the availability of sandy beach habitat. Wave height
also affects  spawning activity with  rough  water (waves over 12")
preventing spawning.  Eggs are laid in clusters or nest sites along
the beach,  usually between the tide marks. In a Delaware study, the
average number of eggs per  cluster was 3,650 (Shuster and Botton
1985). Several nests  are made during  one  beach trip  and females
will return on successive tides  to lay more eggs.  Fecundity, the
total number of eggs per female per year, is approximately 88,000
(Shuster  1982).  Egg  development  is  dependent on  temperature,
moisture  and  oxygen  and usually takes  a month  or  more.  Upon
hatching, the larvae  are motile and spend  about a week swimming
around until they settle to  the bottom  and molt. Although there is
the possibility of wide dispersion during the free-swimming period,
most larvae settle in shallow,  intertidal  areas near  the beaches
where they  were  spawned.  There is some  evidence from a Maryland
geological core survey that small horseshoe crabs  bury themselves
in intermittently submergent  shoal areas in the coastal bays (J.
Casey, pers. comm.). Juvenile horseshoe crabs generally spend their
first and  second  summer on the  intertidal  flats  (Shuster 1982).
Only 1 juvenile  (horseshoe crabs  between 1"  and  5" carapace width)
has been caught  in Maryland's coastal bay area in over 20 years of
trawling and  seining.  Juvenile  crabs  have been observed  in the
Chesapeake Bay but more information-is needed on this life stage.
Older crabs move out of  intertidal  areas and  are  found several
kilometers offshore except during breeding migrations (Botton and
Ropes 1987a).

     Limited data on the  distribution  and abundance of horseshoe
crabs in  the  Chesapeake  Bay  exist but  are  largely unpublished.
Horseshoe crabs are present year-round near the mouth of the Bay
and  have  been documented  in the  Rappahannock  River,  the Miles
River, Eastern Bay, the Chester and Choptank rivers. Horseshoe crab
exoskeletons are a common occurrence on Bay beaches north of the
Bay  bridges.  Spawning has been observed around the mouth of the
Patuxent River (H.  Hornick,  MDNR,  pers.  comm.) and probably occurs
in other areas throughout the Bay. Spawning areas  in the Bay have
not been well  documented because  spawning does not occur in easily
observed,  large concentrations   and  prime  spawning  habitat  is
scattered throughout the Bay  (Shuster  1985). Horseshoe crabs have
been observed spawning in the coastal bay areas in early June (J.
Casey, MDNR, pers. comm.). Horseshoe crab eggs and developing young
have been found subtidally,  in the sandy substrate in the Isle of
Wight Bay during May and June (A. Wesche, MDNR,  pers.  comm.).

     In order to  grow,  the horseshge  crab  must molt  or shed its
chitinous  exoskeleton.  Molting  occurs several  times  during the
first two to three years.  As the  horseshoe  crab  grows  larger there
is more and more time between molts.  It usually takes at least 16
to 17  molts to reach sexual  maturity  over  a  period  of  9  to 12
years. Males develop specialized clasping claws  during their final
molt  for  holding the female  during reproduction.  Females reach

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maturity one year later than males  and consequently, go through an
additional  molting  stage.  Once  sexual  maturity  is  reached,
horseshoe crabs no longer molt and  can live an average of 14 to 18
years in the northern  part of their  range.  Adult horseshoe crabs
feed mainly on  marine worms and shellfish including razor clams and
soft-shell  clams  (Shuster 1950,  Botton  1984).  Because  they lack
jaws, horseshoe crabs  crush  and  grind their  food items using the
spiny bases of their legs then push the small food particles into
their  mouths.   Horseshoe  crabs  can  tolerate  a  wide  range  of
temperatures and have special physiological processes that enable
them to survive low oxygen environments.  Adult horseshoe crabs have
been found  burrowed  into anoxic muds on  intertidal  flats  at low
tide but spawning adults will avoid  anaerobic  sediments in beach
areas (Botton et al.  1988). They can move out of the water during
spawning and survive extended periods of time out of the water if
their book gills are  kept moist.  Effects  of temperature on Limulus
were reported by Shuster  (1978) from Mayer (1914). Mayer observed
differences in  thermal  response  between specimens collected from
northern  and  southern  locations.   Limulus  from  Florida  could
tolerate   warmer  temperatures    (46.3°C)    than  Limulus   from
Massachusetts  (41°C) .  Maximum activity  was  reported  at 41°C for
Florida individuals and  38°C for  Massachusetts individuals.

     Horseshoe crabs play an important ecological role in the food
web  for migrating  shorebirds and  juvenile Atlantic  loggerhead
turtles  (Botton  1983,  Keinath et al. 1987). Delaware  Bay  is the
principal breeding location  for  horseshoe crabs and  is  also the
second  largest staging  area  for  shorebirds  in  North  America.
Migratory shorebirds arrive in Delaware Bay and Maryland's Atlantic
coast at the peak of horseshoe crab mating in mid-May and June and
typically spend two  weeks  in the  area.  At  least 20  species  of
migratory birds rely on horseshoe crab eggs to replenish their fat
supply  during  their  trip to Canadian breeding  grounds.  The food
supply  provided by  the  eggs has been  estimated  at  320  tons
(Delaware Dept. of Nat.  Res.  1987) . The  importance  of this feeding
area  has  been  recognized  by  Delaware  and  New  Jersey  and,
consequently, twenty-five miles of shoreline have been set aside as
a reserve for  shorebirds and horseshoe  crabs. The reserve  is the
first in a proposed International Shorebird Reserve System.  Eleven
sites have  been identified  as  critical stop-over areas used  by
shorebirds during their  flights  between southern wintering sites
and northern breeding grounds. Beca'use  these areas are regularly
used by large numbers  of shorebirds at specific  times of the year,
they are particularly vulnerable to disruption.  The collection of
horseshoe crabs by hand from spawning beaches disturbs the feeding
of shorebirds. A decrease  in the number of  horseshoe crabs would
leave a large portion of migrating shorebirds without the necessary
food resources to complete their trip to the breeding grounds.

     Adult horseshoe crabs also form a significant part of the diet
of juvenile Atlantic loggerhead turtle,  a threatened species that

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utilizes the Chesapeake Bay as a  summer  nursery area (Keinath et
al.  1987,  Lutcavage and  Musick   1985).  Horseshoe crab  eggs  and
larvae are also a seasonally preferred food item of invertebrates
and  finfish. All  crab species and .several  gastropods,  including
whelks, feed on horseshoe crabs.  In the Delaware River  from May
through August, striped  bass  and white perch  eat horseshoe crab
eggs. Eggs and larvae are also eaten by American eels, killifish,
silver perch, weakfish, kingfish,  silversides,  summer flounder and
winter flounder (Shuster 1982).

Biological Profile

Spawning and Larval Development
Spawning season:
Spawning area:




Location:


Juveniles

Location:
Salinity:


Temperature:



Dissolved oxygen:
Varies latitudinally but in the Delaware
Bay area,  generally peaks in  late May-
June during the high tide and full moon.
Have  been  observed   spawning  in  the
Maryland coastal bay areas in early June.

Center of  abundance is in Delaware Bay
with adults occurring as far north as
Maine and as far south as the Gulf coast
of Florida and the Yucatan peninsula.
Protected  sandy  beaches  between
marks within bays and coves.
tide
Inhabit  intertidal  and  shallow  waters
associated  with  tidal marshes,  usually
near breeding beaches. They move further
and   further   from  the   beaches  with
increasing age.

Can   tolerate   lower  salinities  than
adults, 5 ppt to 32 ppt.  (Shuster 1982).

Can   withstand    a    wide   range   of
temperatures,  probably similar to adults,
15-40°C (Shuster  1982) .

Specific  oxygen  requirements have  not
been cited in  the literature.  The rate of
oxygen consumption is  inversely related
to body weight, thus  smaller animals have
a greater oxygen consumption than larger
ones  (Shuster  1982).

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Adults

Location:



Fecundity:

Age at maturity:

Longevity:

Age Estimate:
Temperature:

Salinity:



Dissolved oxygen:
Fishery
In the Chesapeake  Bay,  coastal bays and
several kilometers  offshore except during
breeding migrations.

88,000 eggs per female

9 to 12 years

14 to 18 years

Since adults do not molt, the appearance
of the carapace is  a general indicator of
age.   With   increasing   age,   carapace
abrasion from sand-abrasive environments
and  abundance  of  epibionts  changes.
Epibionts are  organisms that  attach to
the   shell   and   include   crustaceans
(barnacles), coelenterates  (jellyfish),
mollusks,  and  algae.   Based  on  this
information, the following age estimates
can be made:
9-10 years old—clean, lustrous carapace;
10-15  years  old—moderate  erosion  of
carapace usually with epibionts;
15+  years—carapace  nearly or entirely
blackened; with epibionts (These darkened
individuals  are preferred  as bait  by
watermen).

15-40°C with  an optimum  between 25-30°C

Usual  range  is from  11  to  31 ppt but
encounter salinities up to 35 ppt on the
continental shelf.

Specific  oxygen requirements have not
been cited in  the  literature. Given the
horseshoe crabs physiology, it is assumed
they can survive low oxygen environments.
Spawning   adults   will  avoid   anoxic
sediments.
       Historical records (Bureau of Commercial Fisheries) from the
Delaware Bay indicate that commercial horseshoe crab landings were
over 4.0 million crabs in the 1800's. By the  1920's the harvest had
dropped to 1.8 million and continued to decline. During the 1940's
and 1950's,  horseshoe crab stocks were exhausted and brought a low

-------
dockside value. Historically, horseshoe  crabs  were harvested for
fertilizers and poultry and  livestock  food.  Currently,  horseshoe
crabs are commercially harvested for use as eel, conch, and catfish
bait along the Atlantic  coast. The bait eel fishery prefers female
horseshoe crabs with eggs. Commercial harvest  from the northeastern
Atlantic coast has ranged between 10,000 pounds and  2.0 million
pounds  over  the  last  thirty  years   (Figure  1).  Since  1988,
commercial landings have  averaged 950,000 pounds.  The commercial
statistics are based on an average weight of 4 pounds per horseshoe
crab. Reported dockside  value from the northeastern Atlantic coast
has  ranged  between $300  (1967)  and $132,000  (1989)  (Figure 2).
Fishery statistics probably  underestimate the  catch of  horseshoe
crabs because the sale of  crabs for bait  is often arranged between
private individuals rather than through centralized dealers (Botton
and Ropes 1987b).

     Maryland has been responsible for harvesting between 23% and
78%  of  the total  commercial catch  of  horseshoe  crabs  from the
northeastern Atlantic coast  since 1980  (Figure 1) .  The Maryland
harvest comes from a small directed ocean fishery and bycatch from
the clam fishery.  Between  1978 and 1992,  the commercial harvest of
horseshoe crabs has ranged between 50,000 pounds (1984) and 746,000
pounds (1989)  with a 10 year average  of  357,000 pounds. Preliminary
1993  landings indicate  Maryland harvest has  increased to  1.0
million pounds. Reported dockside value  has  ranged between $1000
(1977) and $121,000 (1993) (Figure 3).  In the last 10 years, over
half  of  the  commercial catch was   reported  between August  and
October when adult horseshoe crabs are migrating offshore. Over 33%
of the catch was  reported  between April and May as horseshoe crabs
are moving into beach areas to spawn.  Historically, horseshoe crabs
have been caught by clam dredges,  otter trawls and hand clam rakes.
In Maryland, most of the horseshoe crab harvest is taken by otter
trawls. Currently, trawling  is  banned in the  Chesapeake Bay and
within 1 mile  of  the  Maryland coast. In Virginia,  the commercial
harvest of horseshoe crabs averaged 190,000 pounds between 1980 and
1988. Since the  ban  on  trawling within  state  waters  (to 3 miles
offshore) was  implemented in 1989,-  horseshoe  crab landings have
decreased  considerably  with landings  averaging  22,000  pounds   .
Reported dockside value  has ranged between $200 (1976) and $26,000
(1987) (Figure 4). To date,  Virginia has limited  their  conch pot
fishery to 20  permits which  limits  the amount  of  horseshoe crabs
used for baiting pots.

     Horseshoe crabs  have been an  important animal  for medical
research.  Scientists  have used  horseshoe crabs in eye  research,
surgical sutures and wound dressing development,  and detection of
bacteria  in  drugs. The discovery  of  Limulus amoebocyte  lysate
(LAL) , a clotting agent  in horseshoe crab blood,  has made  it
possible  to  detect human pathogens like spinal  meningitis  and
gonorrhea  in  patients  and  in  drugs.   Any  drug  produced by  a
pharmaceutical company must  pass an  LAL  test.  In  order  to obtain
LAL, manufacturing companies  catch large horseshoe crabs  and bleed

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them.  The  extracted   blood   is   centrifuged  to  separate  the
amoebocytes from the blood plasma, freeze-dried and processed for
pharmaceutical uses.  In 1989, the U.S. Food and Drug Administration
(FDA) reported 130,000  horseshoe crabs were bled for the production
of LAL. Although the exact number of horseshoe crabs bled by each
company  is  considered  confidential  information,   the  current
estimate of medical  usage  is  200,000 horseshoe  crabs  (B.  Swan,
pers. comm.).  There is a mandated conservation measure by the FDA
requiring the return of  bled horseshoe crabs to the environment.
Although the adults are released alive, they have approximately a
10% greater mortality  than  unbled horseshoe crabs (Rudloe 1983).
Horseshoe  crabs  caught  for medical  use  comprise an  additional
source of mortality and  are not  included  in the commercial catch
statistics.

Habitat Issues

     Since  horseshoe   crabs   undertake   inshore  and  offshore
migrations,  they  are  potentially   affected  by  environmental
degradations in  both  estuarine and  oceanic habitats.  Activities
which alter protected sandy beaches will ultimately have a negative
impact on the  horseshoe crab population since these areas are used
for spawning.  Many of  the sites utilized  by horseshoe  crabs and
shorebirds are  also  utilized by  man.  The rate at which coastal
wetlands and  beach areas  are lost  is directly  related to  the
density of human population (Gosselink and Baumann 1980). Coastal
land development and beach  erosion 'practices such as bulkheading
and  placing rip-rap,  alter beach topography  and  make  beaches
unsuitable for spawning. Beach replenishment activities  may also
have an  effect  on horseshoe crab habitat. Tidal flat  areas are
extremely  important   to  newly-hatched  larvae.   Landfills  and
revetment activities turn  tidal  flats  into  pebble  beaches  which
larvae cannot use. Channel  dredging  and overboard spoil disposal
could also  have unknown effects. In Japan,  extensive diking, polder
(an area of low-lying  land that has been reclaimed from a body of
water and is protected by dikes)  construction and pollution have
reduced  the  Japanese   horseshoe   crab,  Tachypleus  tridentatus.
population to the  status of endangered species  (Itow  1993) .  The
Japanese horseshoe crab  is  ecologically similar  to  the American
horseshoe crab.

     Water quality requirements for horseshoe crabs have not been
well defined. There is  little information on the  effects of toxics,
contaminants,  and inorganic compounds on horseshoe crabs. Limulus
is relatively  tolerant  to petroleum hydrocarbons but the tolerance
decreases with  increasing temperature. Horseshoe crab  eggs  and
juveniles exhibited delayed molting and elevated oxygen consumption
after exposure to oil  and chlorinated hydrocarbons  (Laughlin and
Neff 1977).  A high  incidence of deformities  in horseshoe crab eggs
and larvae  was noted in the Seto Island Sea,  Japan, and related to
                                11

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elevated levels of arsenic, chromium, cadmium, lead, and mercury.
Horseshoe crabs are physiologically adapted to tolerate low oxygen
levels and can probably withstand short-term,  anoxic conditions.

Stock Status

     Data from the Northeast Fisheries Center (NEFC) bottom trawl
and ocean clam surveys  (Georges Bank to Cape Fear, North Carolina),
indicate  that horseshoe  crab  abundance was relatively  stable
between 1975 and 1983.  During this  time period, the horseshoe crab
population was estimated between 2.3  and 4.5  million individuals
and  the  commercial  fishery  harvested  an  average  of  176,000
individuals  (approximately 700,000   pounds).  Medical  companies
utilized about 160,000 individuals  which  contributed an additional
10%  mortality   or  16,000  individuals  to  the   total  annual
exploitation. Current fishery statistics  suggest that exploitation
has not increased over the last 9 years (1984-1992) with commercial
exploitation  averaging 184,000  individuals  or  737,000  pounds.
Medical  usage has  increased  slightly  to approximately  200,000
individuals or an additional mortality of 20,000 individuals. Mean
number of horseshoe crabs per tow from the NEFC bottom trawl survey
was greatest north and south of Delaware Bay and off the Maryland
coast  (Botton and  Ropes  1987b).  Seasonal  surveys  suggest that
horseshoe crabs  found  between Virginia and New  Jersey consist of
Chesapeake and Delaware Bay individuals.

     The  spawning  horseshoe  crab  population  in  Delaware  is
currently being  monitored  by an annual  census which  started in
1990.  Recent population  estimates  from Delaware  beach  surveys
indicate a  drop  in horseshoe  crabs from 1.2  million  in 1990 and
1991 to  less than 400,000  in 1992 and 1993  (Swan  et  al.  1991).
Spawning  population estimates,  however, are not  statistically
robust. Trawl  surveys  were  conducted by  the  Delaware Division of
Fish and Wildlife in Delaware Bay during April to December, 1990-
1993. The Delaware trawl survey indicated a decrease in catch per
unit of effort  (CPUE)  from  18.6  in 1990  to  3.71  in 1992. "How the
migration of adults between estuaries and the  continental shelf
affect  the  trawl catch  is unknown.  Approximately  90%   of  the
standing stock of horseshoe crabs is  located between Virginia and
New Jersey  (Botton and Ropes 1987a).

Current Laws and Regulations

Virginia

There are no specific laws or regulations that  pertain to horseshoe
crabs. There is  a ban on  trawling within state waters  (up to 3
miles  offshore). Most  horseshoe  crabs  are  taken  by  dredge as
incidental  catch but  some  are  taken directly  for use  as bait.
Special scientific collection permits have been issued to trawlers
to catch horseshoe crabs for medical  purposes.


                                12

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Maryland

There are no specific laws or regulations that pertain to horseshoe
crabs. There  is  a  ban on trawling within the  Chesapeake Bay and
coastal bays, up to 1 mile off the Maryland Atlantic coast. There
is some directed trawling for horseshoe  crabs for bait and for use
in medical research.

Delaware

Horseshoe crab regulations were adopted in January 1992 and include
the  following restrictions:  prohibition  on  the  collection  or
dredging of  horseshoe  crabs  between May 1 and June 7  unless one
holds a valid scientific permit; prohibition  on dredging horseshoe
crabs from leasable shellfish grounds unless  it is your own leased
ground; prohibition  on the possession  of more than  6  horseshoe
crabs  for  persons  under  the  age of 16 unless accompanied  by  a
person who  has been issued a valid permit;  a limitation  on the
number  of  persons  who  may  assist  the holder  of a  commercial
collecting permit to three; prohibition on the possession of more
than 6 horseshoe crabs unless  that person has a valid receipt from
a person who holds a valid horseshoe crab commercial permit; and an
exemption for commercial eel licensees  from horseshoe crab limits
so long as  an annual report on horseshoe crab  catch is submitted to
the Department of Natural Resources and Environmental Control and
the crabs are only used for bait.

New Jersey

Horseshoe  crab  regulations  were  implemented  in  May   1993  and
include: requirement of  a free horseshoe crab  permit  in order to
harvest  crabs by  hand  or by  any  lawful  gear;  collection  of
horseshoe  crabs  for scientific  purposes is legal  so long  as  a
scientific collection permit is obtained; prohibition on the taking
of crabs from the Cape May Canal to Stow  Creek in Cumberland County
(the  area  considered  to be  the most  important  horseshoe  crab
spawning areas)  from  May 1  through June   7  except  on Monday,
Wednesday and  Friday from one hour  after sunset until  one  hour
before sunrise; and a requirement for horseshoe crab harvesters to
provide monthly reports on the size of harvest, area of collection,
gear  usage,  and  any  other  information  the  Department  deems
necessary.
                               13

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References

Botton, M.L.  and J.W. Ropes.   1987a.   Populations  of horseshoe
     crabs,  Limulus  Polyphemus,   on  the  northwestern  Atlantic
     continental shelf. Fish. Bull. 85(4):805-812.

Botton, M.L. and J.W.  Ropes.   1987b.  The  horseshoe crab, Limulus
     polyphemus,  fishery  and  resource   in  the  United  States.
     Mar.Fish. Rev. 49(3):57-61.

Botton, Mark  L.   1984.   Diet and food preferences  of the adult
     horseshoe  crab,   Limulus polyphemus  in  Delaware Bay,  New
     Jersey, USA. Marine Biology 81:199-207.

Botton, M.L.,  R.E. Loveland and  T.R.  Jacobsen.   1988.   Beach
     erosion and geochemical factors: influence on spawning success
     of horseshoe crabs (Limulus polvphemus) in Delaware Bay.  Mar.
     Bio.  99: 325-332.

Cohen, E.  (ed.).  1979.  Biomedical Applications of the Horseshoe
     Crab (Limulidae).  Alan R. Liss,  Inc., New York.  688 p.

Delaware Department of Natural Resources and Environmental Control.
     1987.  Shorebirds and the Delaware Bay.  Office of Ocean and
     Coastal Resource Management, Dover,  Delaware.

Gosselink,  J.G.  and   R.H.  Baumann.  1980.  Wetland  inventories:
     Wetland loss along the Unite States coast.  Z. Geomorphol. N.F.
     Suppl. 34:173-187.

Itow, Tomio.  1993. Crisis in the  Seto Inland  Sea: The decimation
     of the horseshoe  crab.  EMECS Newsletter No. 3:10-11.

Keinath, John A., J.A. Musick, and R.A. Byles.  1987.  Aspects of
     the biology of Virginia's sea  turtles: 1979-1986.  VA J. Sci.
     38(4):329-336.

Laughlin,   R.B.  and J.M.  Neff.   1977.   Interactive  effects  of
     temperature, salinity shock and chronic exposure to No. 2 fuel
     oil  on survival,  development rate  and  respiration  of the
     horseshoe crab,  Limulus polyphemus.  In D.A. Wolff  (ed), Fate
     and effects of petroleum hydrocarbons in marine organisms and
     ecosystems, p. 182-194. Pergammon, Oxford.

Lutcavage, M. and  J.A. Musick.   1985.  Aspects of  the biology of
     sea turtles in Virginia.  Copeia (2):449-456.

Mayer, A.G.   1914.    I. The  effects of temperature upon tropical
     marine  animals.    Papers Tortugas Lab  Carnegie  Inst.  Pub.
     183(6):l-24.


                                14

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Rudloe, A.   1983.  The effect of heavy bleeding on mortality of the
     horseshoe   crab,   Lixnulus   polyphemus.   in   the   natural
     environment. J. Invert. Pathol. 42:167-176.

Shuster, C.N.,Jr.   1950.   Observations  on the natural history of
     the American horseshoe crab, Limulus polyphemus.   3rd Rept.,
     Investigations of Methods of Improving the Shellfish Resources
     of Massachusetts, Woods Hole Oceanographic Institution, Contr.
     No. 564:18-23.

Shuster,  C.N.,Jr.    1962.    Serological  correspondence  among
     horseshoe "crabs"  (Limululidae).  Zoologica 47(1):1-8.

Shuster, C.N.,Jr.  1979.  Session I:  Biology of Limulus polyphemus.
     In: Elias Cohen et al. (editors), Biomedical Applications of
     the Horseshoe Crab (Limulidae).  Alan Liss, Inc.   (NY):l-26.

Shuster, C.N.,Jr.  1982.  A pictorial review of the natural history
     and ecology of the horseshoe crab,  Limulus polyphemus.  with
     reference to other Limulidae. In:  (eds)  J. Bonaventura et al.
     Physiology and biology of horseshoe crabs: Studies on normal
     and environmentally stressed animals, p.1-52.   Alan R. Liss,
     Inc. New York

Shuster, C.N.,Jr.  1985.  Introductory remarks  on the distribution
     and  abundance  of  the  American  horseshoe  crab,   Limulus
     polyphemus,  spawning in the Chesapeake Bay area.  In: Valerie
     Chase (editor), The Chesapeake: Prologue to the Future, Proc.
     Chesapeake   Bay   Symposium,   National   Marine   Educators
     Conference:  34-38.

Shuster, C.N.,Jr. and M.L. Botton.  • 1985.  A contribution to the
     population  biology  of horseshoe  crabs,  Limulus  polyphemus
     (L.),  in Delaware  Bay. Estuaries 8(4):363-372.

Swan, B.L., W.R. Hall,  Jr.  and C.N. Shuster  Jr.  1991.   Limulus
     spawning  activity  on Delaware  Bay shores  25  May  1991.
     University of Delaware, Sea Grant Program, Lewes, Delaware.
                               15

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Section 2. Horseshoe Crab Management

     There is currently no coastal management  plan for horseshoe
crabs. The source documents for the development of the Chesapeake
Bay and Atlantic Ocean Fishery Management Plan for Horseshoe Crabs
were definitive works by C. N.  Shuster,  Jr.,  M.L.  Botton and J.W.
Ropes, and A. Rudloe. The following management strategies have been
developed  and  serve as the  basis for  identifying the goal  and
objectives.

A. GOAL AND OBJECTIVES

The goal of this plan is to:

     Protect the horseshoe crab  resource in the Chesapeake Bay and
     Atlantic Coast to insure its  continued role in the ecology of
     coastal  ecosystems,   while  providing   the  opportunity  for
     commercial, recreational and medical usage over time.

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

1) Promote harvesting practices which minimize waste and maximize
the  biological  and  economic   return   from  the  horseshoe  crab
resource.

2) Promote studies  to improve  the understanding  of  life  history
aspects and population dynamics of horseshoe crabs.

3) Determine  the optimum spawning stock biomass  for horseshoe crabs
that can support harvest practices, medical research, and migratory
shorebird populations.

4)  Improve collection  of catch  and effort statistics for  the
commercial horseshoe crab fishery.

5)  Make Chesapeake  Bay  and Atlantic  coast management  actions
compatible where possible with Delaware and New Jersey actions.

6) Develop guidelines for identifying and protecting horseshoe crab
spawning, juvenile and adult habitat.
B. HORSESHOE CRAB MANAGEMENT STRATEGIES

1) Ecological Value: Horseshoe crabs play an important ecological
role in the food web of migrating shorebirds. At least 20 species
of migratory birds rely on horseshoe crab eggs to replenish their
fat supply  on  their way to Canadian  breeding  grounds.  Migratory
shorebirds are present in the Delaware/Chesapeake Bay region from
mid-May through June. During this time, horseshoe crabs leave the
water to deposit their eggs  on certain  spawning beaches. Horseshoe


                                16

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crabs are vulnerable to human disturbances when they are out of the
water. Shorebirds are also affected by human disturbances when they
are feeding on the beaches. A decrease in the number of horseshoe
crabs would leave a large portion of migrating shorebirds without
the  necessary food resources.  Horseshoe crab eggs  are also  a
seasonally preferred food item of several finfish species. In the
Chesapeake Bay, adult  horseshoe  crabs are a major item in the diet
of juvenile loggerhead turtles, a threatened species. Both Delaware
and New Jersey have implemented regulations  to protect migratory
shorebirds  and  horseshoe  crabs.  Their  regulations  include:  a
prohibition on  taking  horseshoe crabs  between May 1 and  June  7
during the peak in shorebird migration and horseshoe crab spawning;
a recreational possession limit; and a commercial permit. Limits on
horseshoe crab harvest in  Delaware  and  New Jersey  could increase
fishing pressure  in Maryland  due to market  demand.  The offshore
distribution  of  horseshoe  crabs suggests that  there may  be some
gene flow between Delaware Bay and Chesapeake Bay populations.

     Strategy 1.1
     Maryland  and  Virginia will protect the  ecological  role of
     horseshoe crabs by protecting  horseshoe crab  spawning areas
     and monitoring harvest.

          Action 1.1
          Maryland and Virginia will prohibit the hand collection
          of horseshoe crabs from beaches during the peak time of
          shorebird migration, May 1 through  June 7.

               Implementation 1.1
               1995

          Action 1.2
          a)  Maryland  will prohibit the scraping,  trawling or
          dredging of horseshoe crabs between May 1 and  June  7
          within the Chesapeake  Bay,  coastal  bay areas, and 1 mile
          of the Atlantic coast.
          b)  Virginia will continue  its ban  on trawling within
          state waters (up to 3  miles offshore).

               Implementation 1.2
               a) 1995   b) Continue

          Action 1.3
          Virginia will prohibit a directed horseshoe crab fishery
          between May 1 and June 7,  continue mandatory reporting in
          the  conch  dredge fishery  and  monitor  the bycatch of
          horseshoe crabs.
               Implementation 1.3
               1995
                               17

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2)  Stock  Status:  Data  from  trawl  and clam  surveys  indicate
horseshoe  crab  abundance  was relatively stable between  1975 and
1983. During the same time period, an  average of 700,000 pounds of
horseshoe crabs was harvested from the  northeastern Atlantic coast.
Commercial exploitation has not significantly changed over the last
9 years  (1984-1992)  and  landings  have averaged 736,000  pounds.
Medical usage has slightly increased  from  160,000  individuals to
approximately 200,000 individuals. There is about a 10% mortality
associated with  bleeding  crabs.  Most horseshoe crabs  are caught
during the spring and summer,  the time  when they are reproductively
active. Egg-bearing females are targeted for the eel  and conch bait
fisheries. Recent spawning stock  estimates and fishery independent
trawl data from Delaware indicate a drop in the number of horseshoe
crabs. There is a need to improve the spawning stock survey so it
is statistically robust.  There is  also  a  need to  obtain better
information on horseshoe crab population dynamics, especially from
the Chesapeake Bay area.

     Strategy 2.1
     Maryland and Virginia will coordinate with Delaware and begin
     to develop a spawning stock  census  of  horseshoe  crabs which
     will  serve   as  the  basis  for  determining   management
     recommendations as appropriate.

          Action 2.1
          Maryland and Virginia  will  coordinate and  implement a
          horseshoe  crab spawning stock  census  in  the Chesapeake
          Bay, coastal bays and along the Atlantic coast.

               Implementation 2.1
               1995

          Action 2.2
          Maryland and Virginia will promote and encourage research
          on horseshoe crab estimates  of population abundance, age
          and size composition, mortality estimates,  and migration.

               Implementation 2.2
               Open

3) The Fishery:  Since 1987,  the commercial  harvest of horseshoe
crabs  along  the  northeastern   Atlantic   coast   has  gradually
increased. Current levels  (1989-1992)  of harvest are approximately
1.0  million   pounds.  Commercial  horseshoe  crab  statistics  are
incomplete, especially in Maryland.  Preliminary data indicate the
Maryland  harvest increased  to  1.0 million pounds during  1993.
Increased  landings may be  the result  of  better  reporting methods
but information on fishing effort is  needed in  order  to evaluate
commercial landings  statistics.  Horseshoe  crabs  are commercially
harvested for use as  eel,  conch,  and catfish bait. Horseshoe crabs
are also  important laboratory animals for  medical  research. They
are captured and bled to obtain Limulus amoebocyte lysate  (LAL), a

                               18

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clotting agent used  to  detect  human pathogens in drugs. Although
the crabs are released alive, they experience a greater mortality
than  unbled horseshoe crabs.   Horseshoe crabs  are particularly
vulnerable to being overfished because of their late maturity  (9-11
years), their dependence on coastal and  bay spawning beaches which
are being lost as a result of the development  of coastal areas, the
selective nature of the bait fishery for egg-bearing females, and
their  seasonally  abundant,  easily  harvested,  inshore  spawning
aggregations. The  evidence  for  overharvest of a year-class would
not  be  apparent  for  at  least  9  or 10  years.  Under  these
circumstances, prudent management recommendations are warranted.

     Strategy 3.1
     Maryland and Virginia will monitor  the commercial and medical
     harvest of  horseshoe crabs and improve the  quality of data
     obtained from the commercial fishery.

          Action 3.1
          a) Maryland  will require horseshoe  crab  harvesters to
          provide monthly reports on the size of harvest, area of
          collection,  gear  usage  and  any  other  information the
          Department deems necessary.
          b) Maryland will determine if a special  permit to harvest
          horseshoe  crabs  is necessary after  evaluating the new
          federal reporting system and the results of the monthly
          reports.

               Implementation 3.1
               1995

          Action 3.2
          Virginia   will   continue  their   mandatory   reporting
          procedures implemented in January,  1993.

               Implementation 3.2
               Continue

          Action 3.3
          Maryland and Virginia will survey American eel harvesters
          and their use of horseshoe crabs  by sex for bait.


               Implementation 3.3
               1995


4) The  Habitat:  Limulus is  a  generalist  and is  not as severely
restricted  by environmental  conditions as  many other  aquatic
species. Protected beach areas are  essential habitat for horseshoe
crab spawning.  Beach  stabilization  practices such as the placement
of "clean fill," i.e., bricks,  cinderblocks and coarse  gravel, in
the  intertidal   zone  may  seriously affect  egg-laying  habitat.

                                19

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Activities which impact spawning areas will have a negative impact
on the horseshoe crab population. Habitat destruction has seriously
reduced the horseshoe crab population in Japan.

     Strategy 4.1.1
     The  jurisdictions will  define  and  protect horseshoe  crab
     spawning  areas   and  areas  that  are   used  by  migrating
     shorebirds.

          Action 4.1
          Maryland and Virginia will  initiate a study to delineate
          the geographic distribution of  horseshoe  crab spawning
          habitat in the Chesapeake Bay and coastal bays if funding
          is available.

               Implementation 4.1
               Dependent on funding

          Action 4.2
          The jurisdictions  will  promote  research to  define the
          water quality requirements for horseshoe crabs.

               Implementation 4.2
               Open

          Action 4.3
          The  jurisdictions  will  continue  to  work  with  the
          Chesapeake Bay Program,  the Coastal Bay Initiative and
          water quality improvement goals for the Bay and coastal
          areas.

               Implementation 4.3
               Continue
                                20

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1 . 1 MD & VA will prohibit the hand collection of horseshoe crabs from beaches duri
the peak time of shorebird migration, May 1-June 7.











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1 .2 a) MD will prohibit the scraping, trawling or dredging of horseshoe crabs betwee
May 1 and June 7 within the Chesapeake Bay, coastal bay areas and within 1 mile of
Atlantic coast.
b) VA will continue its ban on trawling within state waters.














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1 .3 VA will prohibit a directed horseshoe crab fishery between May and June 7, cont
mandatory reporting in the conch dredge fishery and monitor bycatch.
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2.1 MD & VA will coordinate and implement a horseshoe crab spawning stock censu
the Chesapeake Bay, coastal bays and along the Atlantic coast.














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2.2 MD & VA will promote and encourage research on horseshoe crab estimates of
population abundance, age and size composition, mortality estimates and migration.

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3.1 a) MD will require horseshoe crab harvesters to provide monthly reports on the si
of harvest, area of collection, gear usage and any other information the Department di
necessary.
b) MD will determine if a special permit to harvest horseshoe crabs is necessary after
evaluatinng the new federal reporting system and the results of the monthly reports.


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3.2 VA will continue their mandatory reporting procedures.














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3.3 MD & VA will survey American eel harvesters and their use of horseshoe crabs 1
sex for bait.

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4. 1 MD & VA will initiate a study to delineate the geographic distribution of horsesh
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4.2 The jurisdictions will promote research to define the water quality requirements ft
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