The following message gives some specifics regarding the shorebird and
horseshoe crab problem in New Jersey, USA and is submitted by:

     Joan Walsh, Director of Research, 
     Cape May Bird Observatory.  
     
I can be reached at CMBOJOAN@ALGORITHMS.COM or 609-861-0700.  
This message summarizes information from several sources - and much of 
the work is ongoing.  Errors in the summary are mine.  

The e-mail tree is working well to inform people about the shorebird and
horseshoe crab problem in Delaware Bay, New Jersey, USA.  Several people
have asked us for  a synopsis of the problem, and it goes like this.

*Delaware Bay hosts the second largest concentration of migratory shorebirds in
North America.  There has been a significant decline in the number of
sanderlings and semipalmated sandpipers counted in Delaware Bay since 1986,
and in 1996 the count of red knots was the lowest ever.  During the 1997 most
(73% of the peak week count) shorebirds were found on the Delaware Side of the
bay (source:  NJ Non-game and Endangered Species Program).  Delaware has a
moratorium on the harvest of crabs, and most crabs too were in Delaware.

*The shorebirds using Delaware Bay feed on Horseshoe Crab eggs and
invertebrates.  Horseshoe crab deposit eggs in masses about 15cm below the
surface.  Females depositing eggs may dig up a previous female's nest if
the density of nests is high.  Research by Bob Loveland of Rutgers Univ.and
Mark Botton of Fordham Univ. indicates eggs on the surface have dropped 10 fold
in 6 years. (pers comm Botton & Loveland, ongoing work).  Work on the shorebirds
has indicated they arrive in NJ below their fat free weight, and that Red Knots
must gain 3g. daily (for 20 days straight) to be ready for their departure in
late May ( Clive Minton & Alan Baker pers comm).  Without a high density of
horseshoe crabs the eggs are not available to the shorebirds.

*Horseshoe Crabs take 9 - 11 years to become sexually mature and breed
several times each year and for several years.  They have some site fidelity to
breeding beaches, but also will breed on new beaches. Horseshoe crabs have been
heavily harvested from Delaware Bay to be used as bait for catching American Eel. 
The baywide and nearshore take is reported at 780,000 crabs/year, but reporting
of this fishery is notoriously low so the number is probably over 1,000,000
crabs per year.  Until 1995 harvesters were allowed to take spawning crabs off
their breeding beaches.  This resulted in entire beaches being cleaned off three
night per week during the crabs breeding season.  Changes in the regulations in
1996 eliminated the take off the beaches but still allowed it, without a bag
limit, two days per week in the salt marshes along Delaware Bay.  They are also
harvested during the winter on their wintering grounds in the Atlantic
Ocean. This take occurs in New Jersey, Delaware and Federal waters.

*Trawl surveys designed to estimate the stock of commercially harvested
fishes are conducted by Delaware and New Jersey.  The gear used does not target
for crabs, but the methods are consistent.  Delaware's trawl estimated a
steadily declining Horseshoe Crab stock, New Jersey's trawls (conducted in the
Atlantic, the wintering grounds of the crabs, not in Delaware Bay) did not show a
significant decline.

*A volunteer census estimating the number of horseshoe crabs along the
shores of Delaware Bay  has been active since 1990.  Their data indicate the
population is about 1/3 of what it was in 1990.  The decline in the horseshoe crab 
census data covaries with the decline in the Delaware trawl data.  

We feel the evidence supports the following scenario: Horseshoe crabs have
been depleted to the point where the density of crabs is not great enough to
provide food for the shorebirds. This is having a sub-lethal effect on most birds
while they are here, but may lead to a more significant problem when the birds
arrive at their breeding grounds underweight. This will take us years to detect,
and the current state of affairs should cause us to act prudently.  The harvest
of horseshoe crabs, the most significant and controllable source of mortality
for the horseshoe crabs, must be stopped until a sustainable plan is developed
which supports the crabs, the birds and the commercial fishery.  For those of you
interested in commenting by e-mail on the horseshoe crab and shorebird
debacle that has occurred in New Jersey and Delaware, visit the New Jersey homepage
and leave a message on the Governors page.  The address is
http://www.state.nj.us/  From there you are prompted into the Governors page, 
and can leave a message. The Governor's office can be phoned ar 609-292-6000, 
and comments left at that number.