Horseshoe crabs are harvested for their blood for biomedical use and as bait, raising welfare and conservation concerns.
Horseshoe crab bleeding for biomedical use causes demonstrable welfare harm — bleeding captures and procedures cause stress, and a significant percentage of bled animals die. The cascade effects extend to migratory shorebirds like red knots that time their migration to coincide with horseshoe crab spawning and depend on crab eggs as an essential refueling resource. Recombinant alternatives to horseshoe crab LAL are available and approved in some jurisdictions, eliminating the need for bleeding entirely. Transition to synthetic alternatives is both a welfare solution and a conservation benefit for shorebird species dependent on horseshoe crab spawning.