Horseshoe crabs have been around since the age of the dinosaurs. But several factors could threaten their survival. A lawsuit was filed Monday in U.S. District Court in Washington, D.C. to protect this ancient species.
The lawsuit claims that horseshoe crab populations have crashed by as much as 70% in the past few decades. Much of that is from loss of habitat and overharvesting for their medicinal properties.
According to the Florida Fish and Wildlife Conservation Commission, horseshoe crabs' "unique, copper-based blue blood" has a substance known as Limulus Amebocyte Lysate or "LAL".
This compound clumps up in the presence of small amounts of bacterial toxins. That's why their blue-colored blood is prized for testing new drugs and the sterility of medical equipment.
"Anyone who has had an injection, vaccination, or surgery has benefited from horseshoe crabs," the FWC wrote on its website. "Additionally, research on the amazing and complex compound eyes of horseshoe crabs has led to a better understanding of human vision."
The lawsuit from the Center for Biological Diversity says the federal government has failed to protect the crabs, as harvesting for biomedical research has doubled in the past seven years. Conservationists say synthetic compounds are increasingly being used as a replacement for crab blood.
The Center petitioned the federal EPA to add them to the Endangered Species Act in 2024. They say their failure to act prompted the lawsuit.
"Horseshoe crabs have saved so many people, and now it's up to us to pay back that debt and save them," said Will Harlan, a scientist at the Center. "We could lose these living fossils forever if they don't get Endangered Species Act protections soon. It's reckless to delay their obvious need for protection, so we're going to court to force the government to do its job."
Horseshoe crabs are called "living fossils," going back more than 450 million years, predating the dinosaurs and surviving multiple mass extinctions.
The center's lawsuit says that as horseshoe crabs have declined, so have other species like endangered sea turtles, fish and birds. The rufa red knot, a shorebird species that feeds on horseshoe crab eggs during its 19,000-mile migration from South America to the Arctic, was listed as threatened under the Endangered Species Act in 2015. The listing decision cited horseshoe crab overharvesting as one of the contributing factors to the red knot's decline.
In December, the state of New York passed the Horseshoe Crab Protection Act, banning commercial taking for three years, following similar actions in other East Coast states like Delaware, Maryland and South Carolina.
You can learn more about the horseshoe crabs and their medicinal abilities on the FWC's website.
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