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Horseshoe Crabs Return To NJ Beaches For Mating

Each May and June, horseshoe crabs flock to Delaware Bay beaches to lay hundreds of thousands of eggs.

DELAWARE BAY, NJ — It's the time of year where thousands of horseshoe crabs crawl up to Cape May County bay beaches for their 400 million year old mating ritual.

The world's largest concentration of these crabs (not really a crab but an ancient cousin of the scorpion) can be found on the Delaware Bay, according to the New Jersey State Park Service.

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Every year during May and June, these "living fossils" return to the shore where each female horseshoe crab lays up to 100,000 eggs. This happens primarily during new moon and full moon cycles.

At the same time, shorebirds migrate to the Arctic from South America. To fuel up during this long journey, the birds stop and feast on horseshoe crab eggs, according to reTURN the Favor, a group dedicated to saving stranded horseshoe crabs.

Because of this, only a very small amount of eggs will survive to hatch, and then even fewer will grow to adulthood, the group said.

And because the shorebirds need them, New Jersey doesn't allow the harvesting of horseshoe crabs, according to the Department of Environmental Protection - except for one purpose.

Their blood is used in the biomedical industry to detect contaminants in medications and injectable drugs.

About one-third of their blood is taken, and then the crabs are returned to the water.

To see the horseshoe crab spawning for yourself or engage in horseshoe crab events in New Jersey, visit reTURN the Favor here.

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