The Giant Japanese Spider Crab: Massive Undersea Crab

In the cold, dark depths of the Pacific Ocean off the coast of Japan lurks a creature almost mythical in proportion—the giant Japanese spider crab. Reaching astonishing sizes with leg spans over 12 feet and weighing up to 42 pounds, these gentle giants inhabit waters from 160 feet to nearly 2,000 feet deep.

Despite their terrifying appearance, giant Japanese spider crabs are docile creatures unless provoked. Their large claws can certainly inflict injury but attacks on divers are extremely rare. Instead, they spend their days scavenging the seafloor, feasting on dead animals and plants. Some have even been observed forcibly opening shellfish to expose the meat within!

The Japanese have prized these massive crustaceans as a delicacy for centuries. Fishermen bravely venture into the crab’s domain to harvest them, taking care not to catch them during mating season from January through April. This protects the population, as females can lay up to 1.5 million eggs annually. Still, due to overfishing, strict conservation efforts are now in place, including a ban on capturing crabs smaller than 13 inches across.

One of the ocean’s longest-lived species, giant Japanese spider crabs can survive for a century. Throughout their life, they will molt repeatedly, shedding their shell to make room for growth. They have even been known to regrow lost limbs after molting! The current record-holder for size earned the nickname “Crabzilla”, boasting an incredible 12 foot leg span when captured in 2009.

Camouflaging themselves by adorning their shells with sponges and other sea life, these crabs perplexed early researchers. How could such a massive creature elude detection in the ocean depths? We now know that their lifespans and size stem from evolutionary adaptations to the extreme habitat they call home. Still this monstrous crustacean remains one of the sea’s greatest mysteries in its personality clashes of being both gentle giant and zany-eyed predator. While possibly not a crab you’d like to have for dinner, the giant Japanese spider crab is an awe-inspiring example of nature’s ability to produce some of the most bizarre beasts on our planet and beyond our imaginations!