A familiar sea creature once vital to medicine faces threats from overharvesting for its unique blue blood. The article details how horseshoe crab blood enables 40+ years of reliable medication testing by detecting endotoxins, yet the species' population has plummeted along the East Coast. Approximately 200,000 crabs are caught annually in Massachusetts for biomedical purposes.

Eli Lilly and Company has pioneered a lab-made alternative since 2016, reducing reliance on real crabs to 80%. Conservation measures in the state include a 2023 harvest cap and a 2024 ban on April 15–June 7 to protect spawning females. Scientists like Mark Faherty from Mass Audubon note positive trends, with 71% of survey sites showing increased populations over 15 years.