NEW YORK (CBSNewYork) — There is a new layer of protection for New York’s horseshoe crabs. Environmental groups said it’s needed to preserve a threatened marine species, but commercial fisherman are opposed — they’ve called the legislation ‘overkill.’

Inside of a breeding laboratory run by Molloy College in Suffolk County, the next generation of marine biologists is learning about the long history of horseshoe crabs.

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“They’ve been on this planet for 445-million years,” Dr. John Tanacredi explained.

Dr. Tanacredi warns the ancient lineage is now threatened by over-development and over-harvesting.

“There is about an 8 percent decrease in the number of sites supporting horseshoe crabs,” he said.

Dr. Tanacredi and his young research staff said the loss of horseshoe crab habitats would mean much less food for birds who depend on the millions of eggs deposited each year in Long Island’s coastal waters.

There is also a unique quality to horseshoe crabs’ blood that protects humans from infection during medical procedures.

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“They have bacteria in their blood that is used to sterilize and to test medical equipment,” research assistant Fina Castellano said.

Researchers are happy there will be more state oversight to ensure they’re not over-fished — it’s a threat commercial fisherman say is overblown.

“I know that they’re not over-fished. We don’t fish them at all, it’s just people who go for eel, that’s all,” Frank Squeo said.

Sqeuo said horseshoe crabs are only used as bait to capture eel, a relatively small industry. A spokeswoman for one fishing group went further telling CBS2, “this legislation is unnecessary and reflects the environmental lobby’s power,” while labeling it, “another attempt to eliminate the commercial fishing industry.”

Researchers like Tanacredi said the new legislation will keep the fishing industry honest while protecting one of the planet’s oldest living creatures.

New York State is also voluntarily agreeing to meet a federal recommendation to reduce the commercial harvesting of horseshoe crabs by 50 percent.

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