The American horseshoe
crab, Limulus polyphemus, occupies a critical niche
in both the ecology of the Delaware Bay and in human pharmacology. Each
spring as the crab comes ashore to spawn, its eggs provide food for
hundreds
of thousands of shorebirds flying north from South America to breeding
grounds in the Arctic. In human medicine, the crab is bled, with no
apparent
harmful effects, to procure a compound that is used by the pharmaceutical
industry to test intravenous drugs for dangerous bacteria. Yet despite
the
horseshoe crab's importance, no one knew much about its population status
until recently.
In 1990, Delaware
Sea Grant organized the first census of breeding horseshoe
crabs in Delaware Bay. Now, every spring on several peak spawning days,
volunteers donate their time to count crabs on key beaches in Delaware
and New Jersey.
Requirements: Volunteers under age 18 must be accompanied by an adult.
Participation in a training workshop is required to distinguish between
male and female horseshoe crabs and to learn proper data recording procedures.
Time Commitment: The crab census is conducted in May and June.