Sea Cucumber

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There are over 1,200 known species of Sea Cucumber, invertebrate echinoderms of the class Holothroidea. All species are ocean-dwellers, living in waters throughout the world, including the frigid waters near the North and South Pole. They come in a variety of sizes and colors, with the largest (the appropriately named Giant Sea Cucumber) measuring up to several feet in length. Because of their soft bodies, Sea Cucumbers have not fossilized well, but we do have examples dating back around 400 million years to the Silurian.

Sea Cucumbers are scavengers, feeding off of plankton and debris that floats through the water. They draw meals in using tentacle-like appendages around their mouth, and then digest and expel the waste back into the water, where it becomes food for bacteria. Most Sea Cucumber species have very tiny tube-like feet that help them to move slowly.

One of the most interesting (and probably disgusting) habits of Sea Cucumbers is their ability to ward offthreats. Many species will dispel their internal organs out of their anus, distracting the predators and making themselves smaller. They are then able to regrow those organs. Sea Cucumbers also have an an additional tactic up their proverbial sleeves. They can shoot out a sticky mucus that ensnares attackers.

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Sea Cucumbers reproduce both sexually and asexually, depending on the species. Sexual reproduction happens externally, with the sperm and egg intermingling in open water.

Some species of Sea Cucumber are harvested as delicacies in a fishing process known as Trepanging.