Horseshoe Crabs

Auditing the Blue Blood Bank

Horseshoe crabs have been saving our species—are we endangering theirs?

Published June 20, 2017

Humans aren’t the only species that donate their blood for the greater good. The blue blood of horseshoe crabs is used by the biomedical industry to test for toxins in things such as implants, vaccines, and medical implements.

When you give blood, you donate about 10 percent of your blood volume, but horseshoe crabs are drained (without the voluntary donation part) of about 30 percent of theirs. The crab bleeding industry says that bloodletting is not lethal, and that the crabs survive just fine once released, but there’s no doubt that populations are dropping on the Atlantic coast.

In this video, Win Watson and Meghan Owings of the University of New Hampshire explain their research as they try to determine how the current catch, bleed, and release fishery affects the overall health of horseshoe crabs and whether it’s bleeding this “blue blood bank” dry.