The Giant Coconut Crab
With the exalted title of the largest land-based arthropod in the world, it’s a wonder that the giant coconut crab doesn’t get more press than it does. These animals are generally nocturnal and live in many coastal and forest regions of Indo-Pacific islands.
They get their name from their ability to climb coconut palm trees, where they clip off the coconuts, return to the ground, peel of the coconut husks, and hammer the fruits open with rocks or their large claws. On some islands, the giant coconut crab is also known as the robber crab or palm thief because of its habit of taking shiny items.
Giant coconut crabs primarily eat nuts, seeds, and fleshy fruits such as coconuts. However, as omnivores, they will consume other items as well.
These large crabs have a body length of about 16 inches and a leg span of three feet. They can weigh up to nine pounds. There are even accounts of them growing to become more than six feet across and weighing up to 30 pounds. They can also live more than 30 years.
These crabs are unusual because they can’t swim. Though they require water to survive, even smaller ones can drown in water. They have an organ called a branchiostegal lung, which can be described as a cross between gills and lungs. This lung allows the crab to take oxygen out of the air but also has to be kept moist to function. Because of the nature of this lung, one of the most likely times to see coconut crabs is during a rainstorm, as the moisture allows them to breathe more easily.
Though an adolescent has many predators, the only danger to a fully grown coconut crab is mankind—the crab is a delicacy as well as an aphrodisiac in Southeast Asia and the Pacific Islands. Female crabs are particularly in high demand if they have eggs that can be harvested.