Learning about, helping N.J.'s horseshoe crabs

LOWER TOWNSHIP, N.J. - They look like tiny coriander seeds.

And 6,000 of them can easily fit into the bottom of a half-dozen buckets filled with seawater.

But the young horseshoe crabs released into the Cape May Canal on Friday, as part of the 26th anniversary of National Estuaries Day, are the essentials of a grow-and-release program at the Rutgers Aquaculture Innovation Center here.

The project, called the Horseshoe Crab Enhancement Initiative, helps boost the population of the 450-million-year-old species in the Delaware Bay - an East Coast hot spot for horseshoe crabs - and provides a baseline for further study of the ecologically critical and commercially key marine arthropods.

"They're important to us because they play such a vital role in the health of the bay and provide myriad benefits to the local fishing industry, migratory shorebirds population, and the state's biomedical industry," said Michael P. De Luca, senior associate director of Rutgers Institute Marine and Coastal Sciences, which operates the center.

The center invited the public, as well as representatives from environmental groups, to participate in the release of the young crabs, called hatchlings. About two dozen people, including children and their parents who were interested in the event, toured the 22,000-square-foot facility, which is filled with bubbling tanks and research rooms, then watched as the buckets were poured into the canal, one by one.

The Atlantic horseshoe crab (Limulus polyphemus) - not actually a crustacean but a subcategory called a chelicerata that is more closely related to arachnids - is a key species in the Delaware Estuary ecosystem, and is harvested by medical researchers for its blood and used by the commercial fishing industry as bait.

The energy-rich eggs of the crab are eaten by migratory shorebirds as they make the long journey between the North and South Poles annually.

The population of horseshoe crabs in the Delaware Bay - one of the largest spawning populations of the species in the world - has been the focus of heightened conservation efforts designed to protect and preserve the valuable resource, an estimated $50-million-a-year industry.

And the aquaculture programs at the center - which also include similar projects for oysters, surf clams, hard clams, minnows, and several species of finfish - are designed to enhance and accelerate conservation of the species.

The ancient crab species has not been without modern-day controversies. In 2008, the state imposed a moratorium on its harvest after the Atlantic States Marine Fisheries Commission imposed its own limits on the East Coast harvest as populations began dwindling. The moratorium has helped stabilize the population in the Delaware Bay, officials said.

The batch of hatchlings released Friday, which will take seven to 10 years to reach maturity and grow into the brown-shelled, helmet-shape creatures that crawl on bay beaches and float in the surf, were hatched from eggs in the center's laboratory. More than 250,000 crab hatchlings have been cultured and released from the center as part of the project, funded by the DuPont Clear Into the Future program.

It is unclear how many of those released will make it to maturity, De Luca said.

"This is cool," said Zach Reynolds, 8, of Cape May, whose grandmother brought him to the event, where he watched another child help pour the bucket containing the hatchlings into the water.

And the young child's reaction, during an event that took less than 10 minutes to complete, was precisely what the university had in mind when it created the program, De Luca said.

"We really want to raise public awareness and engagement of the public in community restoration efforts as well as stock enhancement of the species in the Delaware Bay," De Luca said.

Eleanor Bochenek, director of the Fisheries Cooperative Center at the Haskin Shellfish Research Laboratory, said that while many research projects are geared only toward "industrial targets," programs like the Horseshoe Crab Enhancement Initiative allow the public to get involved.

"Education outreach is so important for programs like this to succeed," Bochenek said. "This program provides vital research information but also creates an entry level where people can learn about the Delaware Estuary through the study of species like the horseshoe crab."