Japanese Spider Crab
All about the Japanese Spider Crab
Even people who are accustomed to seeing ocean creatures can be startled when they see a Japanese Spider Crab for the first time. This is anything but a normal size crab. It is the world’s largest known arthropod. Begin with the fact that the Japanese Spider Crab has a body size that can be fifteen inches and weigh up to almost forty-five pounds. Then add to that the fact that the leg span of a Japanese Spider Crab is thirteen feet and you have the makings for a pretty scary, or at very least dramatic-looking creature.
A Japanese Spider Crab is orange with white spots on its legs. The claws on a male can be over three feet wide when fully opened. They have compound eyes on their front with two thorns that protrude between them. They have eight legs and two feeding arms.
Japanese Spider Crabs live on the Pacific side of the Japanese archipelago, and are found at depths of from 150 to 800 meters. They are most apt to be found around 200-300 meters. The crabs are caught with small trawling nets and are sold for food but it is not legal during the spring when the females lay their eggs. There are also conservation efforts to protect them from being over harvested.
These crabs are found around Suruga Bay, as well as Sagami and Tosa bays and the Izu Islands. Sometimes they are caught simply for ornamental reasons. They are not generally taken in any great quantity because of the depth at which they live. Their meat is considered a delicacy in Asia. They are omnivores, meaning they eat both animals and plants. They are known scrape the floor of the ocean for algae and plants, and to act as a scavenger, eating the flesh of dead animals.
The Japanese Spider Crab is so named because with all of their various appendages and long legs they resemble a spider. The crab in its larval stage is very small and transparent, and has a round body with no legs. They drift as plankton on the surface of the ocean so many are eaten by predators in that stage of development. Until the eggs hatch as larvae they are carried attached to the mom’s abdomen.
The adult Japanese Spider Crab has a unique self-protection method. These kinds of crabs will pick up other small animals or pieces of sponge and attach them to the top of their shells as a natural camouflage. This works well to keep them hidden as does the fact that it is very dark and cold where they live on the bottom of the ocean.
The Japanese Spider Crab is considered to be an old species, and if often referred to as a living fossil. They live to be up to a hundred years old. You can view the crab in some major aquariums so if you get the chance, go and take a look. The chances of seeing one in its natural environment is pretty much impossible.