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The Blue Bloods of the Sea

They are not very pretty, they have nothing to do with horses and in fact, they are not even crabs, but rather they are relatives of the scorpions, spiders and mites that first evolved some 480 million years ago. During the time known as the Ordovician period, life in the oceans was rapidly diversifying while animals were yet to even make it onto land. The horseshoe crab’s scientific name is Limulus Polyphemus.
You might think because they are not particularly attractive, they sort of look like ancient samurai helmets, they are something to be careful not to step on at the beach. When they are lying on the back, they are downright ugly, and they look dangerous. The fact is the horse crab much prefers to avoid any contact at all with humans. The horseshoe crab will avoid the surf, but sometimes can get caught up in it and be tossed around until it lands on its back. It is difficult, sometimes impossible for a horseshoe crab to flip itself over. In fact, there is a whole movement of good-minded people who campaign to “Just flip ‘em!”. Because it is the right thing to do.

Unlike a stingray, the tail won’t kill, but they are sharp and are to be avoided. They may look ominous, but the tail of a horse crab is not poisonous. It can be sharp, but the tail on a horseshoe crab is an ineffective tool for righting the crab when it gets tossed on the beach by the surf and lands on its back.
You might ask well what good is a horseshoe crab? You can’t eat them, would not want to play with them and maybe their tail could hurt you. The fact is that every one of us should be grateful for the horseshoe crab. The horseshoe crab provides medical science with their blue blood that turns green when extracted. Horseshoe crabs are harvested to be bled for that blood and then put back into the sea to eventually be recaught and rebled. Unfortunately, not all survive being bled. The going price for horse crab blood is $15,000 quart. The blood quickly turns green. Unlike human blood, which contains iron- hemoglobin, the horseshoe crab blood is a hemocyanin that contains copper. Scientists use it to maintain the purity of drugs because it is capable of detecting toxins in medical applications. Reporting on “WBUR cognoscenti” William Sergeant wrote, “The LAL test is the only commonly used medical procedure that is based on a single species of wild animal and that animal is declining up and down the East Coast. The crabs are collected in the wild and their brilliant blue blood is extracted to produce LAL. Then the crabs are returned to the waters from which they came. But according to the National Oceanographic and Atmospheric Administration, 10% to 15% of the crabs die in the process. That, in turn, has led to a decline in red knots, endangered shorebirds that depend on the eggs of horseshoe crabs to fuel their migrations from Tierra del Fuego, at the southern tip of South America, to the Arctic Circle.”
The National Wildlife Federation has expressed concern. With the headline, “National Wildlife Federation calls for increased horseshoe crab protections,” Meshal DeSanti wrote on July 22, 2021, RESTON, Va. –“The National Wildlife Federation and its 53 state and territorial affiliates called for increased protection for horseshoe crab along with a transition to a synthetic alternative to horseshoe crab blood for medical testing. The resolution underscores how horseshoe crabs are critical to coastal ecosystems in the Atlantic Ocean and the Gulf of Mexico, where they support threatened and endangered shorebird and fish species. In recent years, horseshoe crab populations have plummeted due to fishing for bait and the use of horseshoe crab blood for biomedical testing and manufacturing.
“Almost every person who has gone to the beach on the East and Gulf Coasts has a fantastic memory of horseshoe crabs — this amazing creature that dates back to the age of dinosaurs — but those experiences are in jeopardy due to overharvesting and climate change,” said Curtis Fisher, regional executive director for the National Wildlife Federation’s Northeast Regional Center. “With this resolution, the National Wildlife Federation and 53 allied wildlife and environmental organizations made clear that we will fight to save horseshoe crabs. Saving these ancient creatures will also help protect the coastal ecosystem, and endangered and threatened species that depend upon the horseshoe eggs as a critical food source.”
The resolution calls on the Atlantic States Marine Fisheries Commission to put into place additional protections for the species including a coast-wide male-only harvest of horseshoe crabs and to put quotas and best management practices into place to reduce mortality impacts from biomedical harvest, along with the adoption of the synthetic alternative.
“Horseshoe crabs fuel entire ecosystems along the Atlantic coast, with long-distance migratory shorebirds and other coastal species dependent on the animal for survival,’ said David Mizrahi, vice president of research and monitoring at New Jersey Audubon, the National Wildlife Federation’s New Jersey affiliate that introduced the resolution. ‘Management practices that protect this species will protect ecosystems, along with reducing the impact of biomedical research. We look forward to working with state agencies to ensure that this species that has protected humans can be protected in turn.”
A component of horseshoe crab blood is used to test for bacterial toxins during the production of vaccines and other intravenous drugs and treatments, severely depleting populations in coastal ecosystems. However, a synthetic alternative to horseshoe crab blood has already been deemed safe and equivalent by the European Directorate for Quality of Medicines and has been used in the development of various pharmaceutical products and processes, and by pharmaceutical company Eli Lilly in the approval of three widely marketed drugs and a Covid-19 antibody test.
‘With the horseshoe crab now under threat of extinction, the development of a safe and sustainable synthetic chemical provides an alternative that allows for medical innovation while protecting this iconic species.’ added Fisher.”
Perhaps the next time you are strolling along the beach and see a stranded horseshoe crab, you might stop for a moment and consider the history of the horseshoe crab. If you see a child torturing an upended crab you might intervene. And you might want to give it more respect, knowing how helpful the strange-looking creature is to humans and wildlife in general. You might want to just flip it back over so it can crawl into the water, if even just out of respect for an old-timer in trouble.