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Fun Facts

  • A female Horseshoe Crab can lay as many as 90,000 eggs each season, usually in clusters of 4,000 – 5,000 at at time. However, only about 10 of those individual embryos will ever become adults. Before they get a chance to hatch, fish, sea turtles, and birds feed on the eggs.
  • Horseshoe Crabs are actually not crabs. They are more closely related to spiders.
  • Horseshoe Crabs have been around for 450 million years, predating the dinosaurs by more than 200 million years.
  • Horseshoe crabs have blue blood because it is copper rather than iron based.
  • The blood of Horseshoe Crabs contains a protein that will clot upon exposure with bacterial endotoxin. In this way, preparations such as insulin or antibiotics can be tested for contamination before being used in people.
  • If you find a Horseshoe Crab upside down on the beach, pick them up like a bowl and turn them over. Never pick them up by their tails.
  • Horseshoe crab eggs are an important food source for migratory birds such as the Red Knot.

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