I think it’s safe to say that now that Massachusetts is now the largest regulatory loophole for horseshoe crabs on the eastern seaboard. It has one of the largest horseshoe crab bait takes, and now two large biomedical companies bleeding horseshoe crabs for LAL, and the largest rent-a-crab program (where crabs are bled and rather than returned to the sea, are sold for bait and killed), and more holding pens (where crabs await bleeding, spawning in the water rather than on beaches) than any other state, and the largest male to female horseshoe crab sex ratios of any state.
—Deborah Cramer
Author of the Narrow Edge
When the Horseshoe Crabs Are Gone, We’ll Be in Trouble.
Deborah Cramer. New York Times. Feb. 16, 2023.
"In the United States, fishermen take some 1.4 million each year, killing almost half for use as bait. Pharmaceutical companies capture and extract blood from the other 700,000 to make the endotoxin test before releasing them to the sea. Up to 30 percent may die as a result. Many others never make it to shore to lay their eggs.
The International Union for the Conservation of Nature considers horseshoe crabs in the United States vulnerable to extinction along much of the East Coast and endangered in New England. Over 20 years of regulation of the horseshoe crab fishery by coastal states has failed to restore these ancient animals to their former abundance."
https://www.nytimes.com/2023/02/16/opinion/drug-safety-horsehoe-crab.html?searchResultPosition=1