Horseshoe crab: Family: Limulidae Phylum: Arthropoda Class: Merostomata (legs attached to mouth) Species: Limulus polyphemus. Status: Four very similar species endemic to Eastern Americas and the Indo-pacific. Two species vulnerable to extinction in 2016.
450 million years ago horseshoe crabs were almost identical to horseshoe crabs living today. They pre-date the emergence of the woody plants that formed coal beds. Their closest modern relatives are spiders and scorpions. They have 10 legs, blue copper-based blood and 10 sets of eyes – including 2 photoreceptors in their tail.
Harvested for fertiliser, fishing bait, and for biomedical bleeding.
For years, HC were unprotected, shovelled up by the dump-truck load, crushed, and spread to fertilise fields in Delaware US. They are now protected in New Jersey, so after 10-year maturation in the Atlantic off Delaware Bay horseshoe crabs return to the beaches to mate.
Their only defence is their strong shell. The stingless tail is used for navigation and balance, their eggs and hatchlings are essential food for migrating Red knots, another endangered species.
Horseshoe crab blood contains proteins that react to the presence of bacteria forming a protective gel. Most people will have benefited from horseshoe crabs because their blood is used by the biomedical industry to detect positive gram bacterial contamination in vaccines and IV drugs. One litre of blue blood was worth about $16000 USD in 2020, “one of the most expensive resources in the world”
A synthetic alternative has been available for many years but it is even more expensive than the crab blood because of the high profits available and a patent protecting intellectual property.
This Double Dagger lino and woodblock print was made by Joanna Bradley in collaboration with Tom Kristensen who carved the coloured background wood blocks and helped research.
This print is about how human greed and disregard can drive the most resilient and biologically perfect creatures to the brink.
Horseshoe crab blood harvest
By Tom Kristensen and Jo Bradley 4 shina woodblocks hand carved and 1 lino block hand carved. Hand printed on Japanese washi paper using a baren
A$100.00
