Sea Cucumber

Scientific Name: Class Holothuroidea

Sea Cucumber

Description: Sea cucumbers are part of a larger animal group called Echinodermata, which also contains starfish and sea urchins. Their body shape is similar to a cucumber, but they have small tentacle-like tube feet that are used for locomotion and feeding. One way that sea cucumbers can confuse or harm predators is by propelling their own toxic internal organs from their anus in the direction of attack. The organs grow back, and it may save them from being eaten!

Size: Depending on the species, sea cucumbers normally vary in size from less than an inch to over 6 feet.

Diet: Sea cucumbers are scavengers that feed on small food items in the benthic zone (seafloor). Algae, aquatic invertebrates, and waste particles make up their diet. They eat with tube feet surrounding their mouths.

Typical Lifespan: Five to ten years.

Habitat: Some live on the ocean floor and others are planktonic, meaning that they float in the ocean with the currents.

Range: Sea cucumbers are found in virtually all marine environments throughout the world.

Life History and Reproduction: Sea cucumbers exhibit sexual and asexual reproduction. Unlike most terrestrial animals, sea cucumber eggs undergo external fertilization—females release eggs into the water that are fertilized when they come into contact with sperm that males have released. In order for this form of reproduction to be successful, many males and females must be together at the same time.

Fun Fact:

When disturbed, sea cucumbers can expose skeletal, hook-like structures that would make them harder for predators to eat.

Conservation status: Stable. They are regarded as delicacies in some countries.

National Geographic Society:
Tree of Life Web Project
Miami University

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