Marine Animals

Horseshoe Crab Biomedical Harvesting Welfare

Horseshoe crabs are harvested by the millions annually for their blue blood used in medical testing, with significant mortality and welfare impacts.

Key Facts

Over 500,000 horseshoe crabs are harvested annually in the US for biomedical use
Up to 30 percent of harvested crabs may die during or after the bleeding process
Their blue blood contains limulus amebocyte lysate used to test for bacterial contamination in medicines
Synthetic alternatives to horseshoe crab blood exist but adoption has been slow

Welfare Considerations

Horseshoe crabs subjected to biomedical harvesting are bled for up to 40 percent of their blood volume before release. Those that survive are returned to the ocean in a weakened state, and mortality rates are disputed but significant. Females often return to spawning beaches with disrupted timing, reducing reproductive success. Synthetic alternatives now fully approved for medical testing could eliminate this welfare impact entirely.

What You Can Do

Support advocacy for transitioning the pharmaceutical industry to synthetic limulus alternatives
Avoid unnecessary use of medicines with unclear supply chains regarding horseshoe crab testing
Advocate for stronger regulation of horseshoe crab harvesting mortality monitoring
Support research organizations working on synthetic LAL alternatives