Sea Life

Are Horseshoe Crabs Dangerous to Humans?

Having round-shaped heads which resemble a shoe on the horse’s foot, the Horseshoe crabs are marine arthropods belonging to the order Xiphosura. They have quite a similar appearance to rays but they are close relatives of spiders and scorpions. Their unique and weird appearance does raise the question if they are dangerous to humans or not. Let’s find out.

Are Horseshoe Crabs Dangerous To Humans?

No. Horseshoe crabs are not dangerous to humans but it’s the opposite. The blood of the horseshoe crabs is of great importance to humans. It is a source of Limulus amebocyte lysate (LAL), which is used by the pharmaceutical industry to develop drugs that can detect endotoxins released by harmful bacteria in the human body. You can read more about the horseshoe crab’s blood here.

Can A Horseshoe Crab Kill Humans?

No. The horseshoe crabs do not pose any threat to humans because they neither attack nor kill humans. If you give a look at their physical appearance, you’ll see they have special tails, called telsons. Some people presume that these tails are poisonous. However, that’s not the case. Their tails are not venomous but they only use their tails to steer themselves and keep their backs clean.

Are Horseshoe Crabs Friendly?

Yes. Horseshoe crabs are of friendly nature as they do not bother the presence of humans and keep swimming on their own. They even prefer to avoid noisy places contaminated by humans. That’s why, any human taking a swim near them does not have to fear, as they neither bite nor sting.

Can Humans Eat Horseshoe Crabs?

Yes, horseshoe crabs are edible and are consumed by people in Japan and Taiwan. Technically, people do not eat the adult crab, but the eggs (roe) of these horseshoe crabs. There is no nutritional importance associated with horseshoe crabs consumption but people usually prefer to consume it because of superstitions. Horseshoe crabs do not have much flesh, but it does contain some toxins which can be removed upon proper washing and cooking.

Are Horseshoe Crabs Poisonous?

No. Horseshoe crabs are not poisonous. People often mistake them for stingrays because of their physical appearance and outward projecting tails. However, their bodies do not contain any poison or toxins. Only a few toxins are present which humans should get rid of before consumption.

Are Horseshoe Crabs Endangered?

Yes, horseshoe crabs are listed as Vulnerable in the red list of the IUCN due to the constant decrease in their number. Humans have been the major cause behind the decline in their population because:

  • Increased human activities have made horseshoe crabs lose their habitat
  • Horseshoe crabs are harvested by humans to produce drugs
  • Humans use horseshoe crabs as a bait
  • Horseshoe crabs are caught for dietary purposes
  • They are collected for the aquarium trade as well
  • Bycatching of horseshoe crabs is happening at large
  • Water pollution has increased
  • Climate change is also affecting the number of horseshoe crabs

Humans have been harvesting horseshoe crabs for medicinal purposes and even though companies claim that once they take their blood, they place horseshoe crabs back in the ocean. It has been observed that most horseshoe crabs die after this process.

The Bottom Line

Horseshoe crabs are not dangerous to humans. They neither bite due to lack of teeth nor sting due to lack of poison but humans do pose threat to their population. The blood of horseshoe crabs is used by pharmaceutical companies to produce drugs, which is why they are harvested at large and the decrease in their number has placed them as vulnerable in the IUCN red list. They need to be conserved to balance the ecosystem.

About the author

Yumna Ahmad

An experienced content writer, photographer, and avid reader amazed by the sea world and its creatures. I am lettin people become fascinated with the ocean planet through my writings.