As keepers of the environment, we have a responsibility to preserve, protect and live harmoniously with the animals that share our planet. As a source of critical proteins that detect the presence of endotoxins in products and instruments used by humans, the Atlantic horseshoe crab and the many uses of this horseshoe crab’s blood has long been treasured by the biopharmaceutical industry.


For this reason, it is critical that we serve as advocates for the humane treatment of these animals, and strive to achieve balance between our need for this valuable material and the livelihood of the animal that provides it. Charles River is proud to play a role in alleviating pressures on horseshoe crab populations through tireless conservation efforts, active animal welfare campaigns and decades of research and development.



Horseshoe crabs save our lives. What are we doing to help save theirs?

Horseshoe crabs ensure the safety of every vaccine, pacemaker, and biomedical device in the United States with their bacteria-detecting blood. Researchers are now asking what we can do to save them from the increasing needs of the biomedical industry.

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Thanks to the Power of Blue Blood

In partnership with the South Carolina Aquarium’s Holland Lifelong Learning program, Norm Wainwright, Director of R&D at Charles River discussed why we owe our lives to the horseshoe crab and the significant role they play in our ecosystem.

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Night at the Aquarium

Tag teaming with the South Carolina Aquarium to learn more about the horseshoe crab population.

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Conservation Initiatives for an Invaluable Partner

Since endotoxins can be so toxic, any product or device that encounters bodily fluids is screened by Limulus amoebocyte lysate (LAL) reagents. John Dubczak, GM of Charles River Microbial Solutions explains the importance of conserving the source of this valuable reagent.

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From Rabbit to Crab to the Lab

Foster Jordan discusses horseshoe crabs, rFC, and what’s at stake for the pharma industry.

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Heather and the Horseshoe Crabs

What is the connection between living fossils and a living person? Ocean lover Heather Bring of Mystic Aquarium speaks about her work and her knowledge of the horseshoe crabs’ role in her medical care.

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From Horseshoe Crabs to the Depths of Space

A Q&A with Mystic Aquarium Scientist-in-Residence and Charles River Senior Director of R&D Norm Wainwright.

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Horseshoe Crabs Stock Status: Sustainable, Flourishing In Southeast

The biomedical industry and ongoing conservation efforts continue to be a positive attributing factor to horseshoe crab sustainability.

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The Environmental Burden of Plastics & Microplastics

How plastic pollution affects horseshoe crabs, their coastal habitats, and the ocean at large.

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Nature’s First Historian

Herodotus may be the first human historian, but to travel farther back in time we need our fossil friends, the ever-evolving horseshoe crab.

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An Ancient Voice for our Ecosystem

Keeping an eye on the kids. New Jersey Researchers hatch a plan to raise baby horseshoe crabs and then track them in the wild.


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2019 ASMFC Benchmark Assessment and Peer Review Report

An assessment of the horseshoe crab stock status in four regions: Northeast, New York, Delaware Bay, and Southeast.

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South Carolina Marine Resources Act

What are the limitations and restrictions, handling requirements, and penalties when collecting horseshoe crabs in South Carolina?

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The LAL Industry’s Remarkable Stewardship of Horseshoe Crabs

Marine scientists document LAL industry's conservation of the horseshoe crab.


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Mystic Aquarium & Charles River’s Horseshoe Crab Count Walk

With a total of 88 horseshoe crabs counted, this year’s Mystic Aquarium Horseshoe Crab Counting Walk at Napatree Point in Westerly, RI was a huge success.

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New England Aquarium and Charles River Presentation

Living Fossils and Blue Blood: The Story of the Horseshoe Crab and Human Health

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Preserving the role of
an ancient mariner

This podcast discusses some of the earliest work undertaken in South Carolina to conserve horseshoe crabs and how it benefits us all.


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Crab Conservation in
South Carolina

Biomedical manufacturers and conservationists alike have a vested interest in making sure these invertebrates continue to thrive and flourish. Find out how the species is faring.

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The Most Noble Fishing There Is

Eureka guest blogger, Jerry Gault, a longtime South Carolina fisherman, talks about his moral duty and legal responsibility to handle horseshoe crabs with care.

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Adventures of Protecting
the Horseshoe Crab

John Dubczak talks about the importance of endotoxin testing in drug development.

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An Ancient Animal's Blood is a Modern Medical Miracle

At night, during the full and new moon in late May and early June, the sands of East Coast beaches host a dance that is a half-billion years old.

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Remarkable Success Story of the Horseshoe Crab

Learn about the horseshoe crabs’ remarkable story of survival and adaptability.

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Horseshoe Crabs Mate in Massive Beach "Orgy"

Horseshoe crabs live in the ocean year-round, but they make one annual visit to the shoreline to lay eggs in sandy, wet beaches.

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Protecting an Ancient Mariner

The Atlantic horseshoe crab has found allies in the biotech community. Find out why.

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Though they look similar to crustaceans, they actually belong to the subphylum Chelicerata, relating them more closely to spiders and scorpions. Limulus polyphemus is found along the Atlantic and Gulf coasts from northern Maine to the Yucatán Peninsula, with the Delaware Bay as the center of the population. This interesting animal is important, not only for the pivotal role it plays in its ecosystems, but also for its valuable contribution
to biomedical research applications.

The true beauty of this remarkable creature, however, is seen in its primitive immune system. Instead of developing antibodies in response to infection, the immune system releases proteins that can bind and kill bacteria. In addition, other immune proteins clot when exposed to waterborne bacteria, a mechanism which forms the basis of the LAL test.


We are committed to employing only fishermen licensed by the Department of Natural Resources to hand-harvest horseshoe crabs from the coastal waters of South Carolina. Our highly controlled and monitored procedures enable us to collect enough raw material for 24 months of LAL production from a minimum number of donor animals. Once the crabs are brought into our lab, they are carefully inspected by trained employees who determine the animal’s health and maturity. After careful collection of a measured amount of horseshoe crab blood, the crabs are returned unharmed to their natural habitat within the same day, and their blood volume rebounds quickly. These practices have allowed Charles River to achieve an industry-leading survival rate of donor animals.

Government Regulations

Much of the continued survival of the horseshoe crab can be attributed to its inherent adaptability, as well as modern-day government protection. Prior to 1991, there were no laws or regulations in South Carolina dealing with horseshoe crabs. Increased fishing industry demands for Limulus polyphemus made it necessary to develop a state-wide management plan to conserve this resource. In 1992, Dr. James Cooper (a pioneer in the research and development of the LAL assay) wrote draft legislation that called for the management and regulation of horseshoe crab fisheries.1 As a result, the South Carolina state legislature enacted laws to protect the indigenous horseshoe crab population. In South Carolina, horseshoe crabs must be harvested by hand and can only be used for biomedical applications (LAL production) and marine biological research, not as bait for the eel and whelk industries. The addition of six island sanctuaries makes the horseshoe crabs in South Carolina one of the most protected species on the East Coast of the United States.

The State of the Population

In 2019, the Atlantic States Marine Fisheries Commission (ASMFC) Stock Assessments emphasized that the horseshoe crab population in the Southeastern Atlantic Coast has remained in good standing for the last several years.2 Additionally, the Southeast Area Monitoring & Assessment Program (SEAMAP) Coastal Trawl Survey, conducted by the South Carolina Department of Natural Resources, shows a population increase over the last several years.3 Results from a South Carolina tagging study also demonstrated that bled horseshoe crabs are able to return to spawning beaches in subsequent years.



1.   SC Code § 50-5-1330 (2012).

2.   Atlantic States Marine Fisheries Commission Stock Assessments.

3.   South Carolina Department of Natural Resources, Marine Resources Research Institute, “Southeast Area Monitoring & Assessment Program: South Atlantic.”


million years

Limulus polyphemus, known as the Atlantic horseshoe crab,
is an ancient mariner with a lineage that dates back


For more information about our commitment to the Atlantic horseshoe crab
or to request a copy of our conservation poster or brochure.

The biomedical industry’s need for the horseshoe crab and the horseshoe crabs invaluable blood has, in fact, driven the development of laws to protect the animal. Their best security is the biomedical industry’s continued reliance on horseshoe crab blood for LAL. Without the need for LAL, the legal protection for the horseshoe crab is not guaranteed, and they would again fall prey to overfishing and use as bait for eel and whelk. For this reason, it is critical that we serve as advocates for the humane treatment of these animals and strive to achieve balance between our need for this valuable material and the livelihood of the animal that provides it. Thanks to its use in biomedical research, the horseshoe crab maintains its protective status, allowing the population to continue to flourish.

Did you know

that LAL PRotects the atlantic horseshoe crab?

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