Beaches on Delaware Bay Continue to Undergo Restoration

A continuing story in New Jersey since Hurricane Sandy has been the restoration of the beach area on Delaware Bay that are spawning grounds for horseshoe crabs and feeding areas for shorebirds.

It's a story worth retelling as these important populations of shorebirds and horseshoe crabs need the  protection that comes this year with the restoration of more beaches on New Jersey’s side of Delaware Bay.

Thompson’s Beach, on a remote stretch of the Cumberland County shore, will see the removal of  shattered bulkheads and the replacement of 40,000 cubic yards of sand for the spawning of thousands of horseshoe crabs.

Four more beaches and a marsh are due for restoration over the next two years in a federally funded $5.1 million operation on behalf of the American Littoral Society and the Conserve Wildlife Foundation of New Jersey.

A ban on horseshoe-crab harvesting on New Jersey beaches has shown an increase in the bay’s population of red knots. But the crabs are still taken for medical uses and as bait and are harvested on Maryland and Virginia shores even though they are part of the Delaware Bay population.


The red knot migrates from southern Argentina to Arctic Canada via the Delaware Bay beaches each spring and relies on horseshoe crab eggs for food to fuel that journey. The bird population was at its lowest in the early 2000s and has recently stabilized at about 25,000.

That is encouraging, but it is less than a third of the 80,000 birds that biologists consider sustainable, and well below its peak of about 92,000 in the 1980s. The red knot was recently listed as threatened under the federal Endangered Species Act,.

Other shorebirds that use the bay beaches have also suffered a sharp decline and may be more endangered than the red know. For example, the ruddy turnstone's numbers are down to 14,000 from some 150,000 during the 1980s.

Larry Niles, a consulting biologist who designs and manages the beach-restoration program and who previously headed the endangered species program at New Jersey’s Department of Environmental Protection, estimates that some 500,000 male crabs and 150,000 females are harvested each year for their blood, which contains LAL, an extract used to ensure that medical products such as intravenous drugs and vaccines are free of contamination. The crabs are bled and then returned to the ocean in an operation that may kill as many as half of them, he said.

The medical harvest has cut the number of females to about 4 million from about 12 million in the 1990s, he said. “There’s no evidence of recovery in the crab population,” he said. “We’re not going to increase the bird population until the crab numbers start increasing.”