The Sea Cucumber, also known as the Edible Sea Cucumber, was first described by scientists in 1830. It has a long, pink to reddish-brown body, which is usually darker dorsally, often green or black.
Sea cucumbers belong to the group or family called "echinoderms. Their closest relatives are the starfish and sea urchins. There are lots and lots of species of sea cucumber found in oceans throughout the world. About 1260 species are said to be recorded by researchers and only few species lives on top of the sea, but a great number of them lives on the sea bed.
They are used as food delicacy as well as medicine in Asia. Sea cucumbers are being hunt on daily basis, but despite this, they are still available and numerous in the wild. Currently they are not on the list of endangered species of animals.
Structure of the Sea Cleaner
The shape of the sea cucumber is an elongated cylinder. It has a worm like body that lays parallel to the ocean's floor. The external surface of the sea cucumber is very soft because it is an invertebrate (without a spine), it also has five rows of tube feet that are all along the length of their body.
Around the mouth there can be more than ten ambulacral appendages, branched, oral tentacles, and ambulacral feet that can be on all sides. The internal structure of sea cucumbers consists of an alimentary canal, which is a long tube that runs from the mouth of the sea cucumber at the forward end to the anus which is at the posterior end of the sea cucumber.
The internal skeleton is reduced to numerous distinctively shaped, tiny calcareous structures (ossicles) in the skin. Most species have five rows of tube feet extending from mouth to anus.
The anal opening is used for both respiration and discharging wastes. The 10 or more retractile tentacles surrounding the mouth are used for taking food (mud containing nutrients or small aquatic animals) or burrowing. Locomotion is usually sluglike, although some deepwater species can swim.
Many sea cucumbers can expel their internal organs through the anus and grow new ones. This may be a device for escape from a predator, or it may occur for physiological reasons. Sea cucumbers shelter pearlfish (Carapus species) in the anal cavity, with the head of the fish extruding.
The most important feature distinguishing the sea cucumbers is a calcareous ring that encircles the pharynx or throat. This ring serves as an attachment point for muscles operating the oral tentacles and for the anterior ends of other muscles that contract the body longitudinally. Sea cucumbers are also distinct as echinoderms in having a circlet of oral tentacles.
Resourceful Creature of the Sea.
Resourceful Indeed
When threatened, some sea cucumbers discharge sticky threads to ensnare their enemies. Others can mutilate their own bodies as a defense mechanism. They violently contract their muscles and jettison some of their internal organs out of their anus. The missing body parts are quickly regenerated.
However, there exist one other surprise that the sea cucumber always invoke in times of threat, that is a reaction that takes the issue of self defense to a new dimension. As you try to move it, the sea cucumber auto-eviscerates, that is, it literally splits its sides and disembowels itself.
Some species of sea cucumbers produce a toxin known as holothurin. This substances is lethal to many kinds of fish. Though dangerous to the eyes and likely to cause a skin rash. Although it is harmless to humans. Islanders have used this substances in their process of poisoning fish, kill or stupefy fish for the table, and it is effective shark repellent.
Some of the toxins produced by sea cucumbers are used as pharmaceuticals. Research in Asia indicates that toxins produced by sea cucumbers, may have potentials for development as pharmaceuticals in the treatment of cancer and infections.
Extracts from sea cucumbers have been injected and processed into medicine by medical practitioners on various situations. Some are used as supplements and alternative medicine for various illnesses.
For instance, Arthritis and rebuilding cartilage as well as lowering of blood pressure are some of the treatment that are aided by this extract. The animals are also processed to produce vitamins and mineral supplements.
Sea Cucumber: Still in Demand.
Harvesting in Progress
Sea cucumbers feed on tiny particles like algae, minute aquatic animals, or waste materials, which they gather in with 8 to 30 tube feet that look like tentacles surrounding their mouths. The animals break down these particles into even smaller pieces, which become fodder for bacteria, and thus recycle them back into the ocean ecosystem. Earthworms perform a similar function in terrestrial ecosystem.
The Indo-Pacific region overall has experienced enormous fishing pressure, with more than half of the region's sea cucumber stocks depleted or over-harvested, In fact, of the 1,260 species worldwide, 16 in the order Aspidochirotida are at risk of extinction.
It's not surprising to most locals or scientists that several sea cucumber populations are going by the wayside. Indigenous knowledge combined with abundance surveys led by organizations such as Wildlife Conservation Society (WCS) and Secretariat of the Pacific Community (SPC) reach similar conclusions that if the harvest continued without conservation policy, it will spell doom in the near future.
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