Horseshoe Crab

Biography of a Survivor
by Anthony D. Fredericks

Horseshoe crabs have been crawling in and out of the oceans since before the time of dinosaurs. Their straightforward way of life and tough armored carapace have been a success story for this arthropod.  But when humans came on the scene, their numbers began declining, which also spelled trouble for numerous shorebirds that depended on them as food source during migration. Horseshoe crabs were once used by fishermen as bait, and faced habitat loss. Nowadays they are protected, especially because they are key to human health, a point I never really understood before reading this book. The crabs' blood is super sensitive to bacterial contamination, so it is used to make a liquid for testing any number of things for sterility- bandages, IV fluids, surgical instruments, parts for joint replacements, etc etc. They are enormously important to the medical field. The horseshoe crabs are bled in sterile conditions and released into the ocean again with a marking that ensures the same crab won't donate its blood twice in a year.

This book is about far more than the blue blood of the crabs though. It's about their curious anatomy (did you know they have ten eyes?) and habits- what little we know of them, most human observation of horseshoe crabs occurring when they come ashore to breed. It's about various organizations that have arisen to protect the horseshoe crab, to study it, and to educate the public (most people find them unattractive which doesn't help their case). Amusingly, the author makes all this material approachable by inserting popular culture references- in this case B-grade 1950's horror movies!

Interesting article on the medical use of horseshoe crabs, and synthetic alternatives that are being developed (before the possibilities of horseshoe crab blood was discovered, rabbits were used- and they gave their lives).

Borrowed from the public library.

Rating: 3/5                    256 pages, 2012