Edible sea urchin
The edible sea urchin, a member of the echinoderm family, is known for its spherical, spiny exterior and its culinary value. Typically found in rocky coastal regions from Norway and Iceland down to Portugal, these creatures have a diameter of 6 to 7 inches (15 to 17.5 cm) and resemble hedgehogs due to their sharp spines. Humans consume certain internal organs, particularly the gonads, known as uni (testicles or ovaries) and roe (eggs), which are considered delicacies in various cuisines. Edible sea urchins primarily feed on marine algae and can travel considerable distances in search of food, utilizing a set of five teeth to grind their prey. They reproduce through external fertilization, releasing millions of eggs and sperm into the water, though only a few larvae survive to maturity. Their life expectancy ranges from five to ten years. This unique marine creature not only plays a role in its ecosystem but also holds cultural significance in culinary traditions around the world.
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Edible sea urchin
The edible sea urchin is a close relative of starfish, sea lilies, brittle stars, sand dollars, and many other echinoderms, or spiny-skinned creatures. The edible sea urchin was given the name edible because some of its internal organs, such as its sexual organs and eggs, are eaten by humans. The two major dishes that come from the sea urchin are uni, made from the ovaries or testicles, and roe, which is the eggs of the urchin.
Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea
Order: Temnopleuroida
Family: Echinidae
Genus: Echinus
Species: Esculentus
The edible sea urchin may be found along the seabeds below the low tide level on the rocky coasts of northwestern Europe from Norway and Iceland south to Portugal. The edible sea urchin was given its name for its edible body parts, its habitat, and its resemblance to the hedgehog. The word urchin is taken from the French word for hedgehog. The edible sea urchin is like the hedgehog with its many spines.
With a round test, or hard, shell-like body, and many sharp, pointed spines, the edible sea urchin typically has a diameter between six and seven inches (15 to 17 1/2 centimeters). A diameter is the measurement of a round object from one side to the other. As an echinoderm, or spiny-skinned, creature, the edible sea urchin is related to starfish, sea lilies, brittle stars, sand dollars, and sea cucumbers.
Inside the edible sea urchin's test are all of its internal organs. The round test has a small, expandable opening on either end. The opening that is visible on the top of the edible sea urchin works to adjust the amount of water within this creature. It helps to regulate the many tube-feet, or tube-like tentacles, around the edible sea urchin's body. The tube-feet sit in between the many spines on the edible sea urchin's body. They are hollow and help to grasp rocks for movement and to catch food. The edible sea urchin controls its feet by the level of water in its body. The opening on the bottom of the edible sea urchin is its mouth. From here the edible sea urchin clings to rocks and feeds on algae.
The edible sea urchin moves along the seabed in search of food. It feeds on marine, or ocean-living, algae, plants, and animals, especially sea mats and sea firs that live on underwater rocks. Unlike some echinoderms, which suck in their food through their stomach, the edible sea urchin has a set of five teeth which it uses to grind its prey. An edible sea urchin may travel several miles (kilometers) in search of food, or it may spend its entire life in one area which has plenty of food.
Male and female edible sea urchins mate in the spring when the water is warm. Both release their eggs and sperm into the water for fertilization. This system of external fertilization is known as spawning. Although millions of eggs are released into the water during spawning, many are swept away by the water currents. The ones that are fertilized begin developing into microscopic edible sea urchin larvae. At this stage in the development the larval urchins are carried through the surface levels of the water. Many are eaten by predators during this stage, but those that survive settle to the seabed and mature.
The edible sea urchin has a lifespan of five to 10 years.
Bibliography
“Edible Sea Urchin (Echinus Esculentus).” The Marine Life Information Network, www.marlin.ac.uk/species/detail/1311. Accessed 24 Apr. 2024.
“Edible Sea Urchin.” The Wildlife Trusts, www.wildlifetrusts.org/wildlife-explorer/marine/starfish-and-sea-urchins/edible-sea-urchin. Accessed 24 Apr. 2024.
“Sea Urchin.” FoodPrint, 7 Jan. 2019, foodprint.org/real-food/seaurchin/. Accessed 24 Apr. 2024.