Sea Cucumbers- Vacuuming up the Ocean Floor

In marine environments such as those found in Belize, many brightly colored and uniquely shaped plants and animals often overshadow other, less ostentatious creatures, such as the sea cucumber. Closely related to the sea star and sea urchin, this generally nondescript creature is found throughout the coral reef environment, as well as along rocky shorelines and sandy coasts. Despite an appearance that would lead most to believe that all the sea cucumber does is occupy space, this creature, in fact, plays more than one important role in the world's oceans.

    Like the sea star, the spiny skinned sea cucumber is equipped with tube feet, located on its underside, that allow it to slowly (3 inches/hour) move along the ocean floor sucking up sand and debris. Incredibly, over the span of a year, this creature can vacuum up to 200 pounds of sand! In addition to ingesting sand, the sea cucumber primarily feeds on sea grass and algae. To grab onto food, the sea cucumber produces mucus, which causes sand and plant debris to stick to its body. At that point, the creature brings its tube feet to its mouth and sucks off the food.

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    It is a good thing that the sea cucumber has evolved such a mechanism because the population of this creature tends to increase very slowly and needs all the help it can get. Sea cucumbers have two sexes that reproduce by broadcast spawning, in which eggs and sperm are released into the surrounding water and fertilized. Consequently, a larva is created, which will eventually grow into an adult species that can range in size from 10 to 30 centimeters.

    In Belize, the sea cucumber currently does not experience any major threats. However, in other parts of the world, the sea cucumber is considered a gourmet delicacy, thus increasing the demand on this creature. During the mid-90s, sea cucumbers of the Galapagos Islands (in South America) experienced a significant population decline due to over-harvesting; currently sea cucumbers are a protected species in that region.

    In addition to the value of sea cucumbers as a food source for humans, these invertebrates also play an important role in filtering sediments and recycling nutrients back into the food web. Likewise, the eggs of sea cucumbers provide nutrients for many marine species. For these and other reasons, the significance of these curious looking creatures cannot be underestimated.

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