Horseshoe Crabs.pdf

Horseshoe crabs have been on the planet for 470 million years, playing a crucial role in human health and ecological balance. Their blood contains a unique compound that can detect bacterial endotoxins, making it essential for testing the purity of pharmaceuticals and medical equipment. The discovery of this property in 1953 led to the development of the Limulus amebocyte lysate (LAL) test, which is used to ensure the safety of vaccines, injectable drugs, and implantable devices.

Each year, hundreds of thousands of horseshoe crabs migrate to the Delaware Bay to spawn, with females depositing up to 80,000 eggs in the sand. However, only about 10% of these eggs hatch and reach adulthood. The crabs' eggs are a vital food source for migratory birds, including the endangered red knot, as well as other shorebirds and sea turtles.

Despite their importance, horseshoe crabs face threats such as overharvesting for bait and the pharmaceutical industry. Conservation efforts, including the "Just flip 'em!" program, aim to protect the crabs and their habitats. Volunteers count the crabs during their annual migration, providing critical data for the Atlantic States Marine Fisheries Commission's Horseshoe Crab Management Board.

Key statistics:

470 million years: the age of horseshoe crabs on the planet
80,000: the number of eggs a female horseshoe crab can deposit in the sand
10%: the percentage of eggs that hatch and reach adulthood
500,000: the overall harvest limit for male horseshoe crabs set by the Horseshoe Crab Management Board for the 2018 season
* 10-15%: the estimated mortality rate for bled crabs returned to the water.