Sea urchin

General, Facts, Project, Fertilization, Development, Recipe, Suppliers, Product, Farming, Consultancy, Reports, MSDS, Study

Primary Information Services

Home. Ordering Information. Contact



Information @ a Glance

  • The sea urchin is a spiny and hard-shelled sea animal which lives on the rocky seafloor, from shallow waters to great depths. These globular marine invertebrates move very slowly along the seabed. There are about 700 different species of sea urchins worldwide.
  • Two common species of sea urchins are the red (Strongylocentrotus franciscanus) and purple
    (S. purpuratus), in shallow waters of California. Both species have been implicated in the decline of kelp beds.
  • In Japan, sea urchins are protected rather than destroyed. Many sea urchins have venomous spines. The biggest sea urchin is the red sea urchin (Strongylocentratus franciscanus); having a test about 7 inches (18 cm) in diameter.
  • Sea urchins eat plant and animal matter, including kelp, decaying matter, algae, dead fish, sponges, mussels, and barnacles.Sea urchins are eaten by snails, sea otters, crabs, sunflower stars, some birds, fish (including wolf eels), and people.
  • Fertilization of sea urchin is external. Female Sea Urchins release several million tiny, jelly-coated eggs at a time. Eggs or sperm are released through five gonophores. As they develop, the tiny larvae (called the pluteus, which have bi-lateral symmetry) swim in the sea and are a component of zooplankton.
  • It takes several months for juvenile sea urchins to form. The time from fertilization to a reproductive adult is from 2 to 5 years.
  • Sea urchins are creatures that live in oceans all over the world. Similar to sea stars, sea urchins have a water vascular system. Their spherical shape is typically small, ranging from about 3 cm to 10 cm in diameter, and their body is covered with a spiny shell.
  •  A common place to find a sea urchin is in coral reefs. Examples of where sea urchins are very commonly found are on the reefs of Hawaii, of the Caribbean and of Australia. Sea urchins have also been reported to cause erosion of reefs in places such as the eastern Pacific, Kenya and the Red sea.
  • So although sea urchins are important to the survival of an ecosystem, they can also become dangerous in great numbers. Other family members include the sea cucumber, sea star and sand dollar.
  • Unfertilized egg, Fertilized egg, Two cell stage, Four cell stage , Eight cell stage, Sixteen cell stage, Thirty two cell stage, Morula stage, Blastula stage, Gastrula stage, Pluteus larval stage are the stages of Fertilization of Sea urchin.
  • Urchins are prized for their edible gonads, known as uni in Japan. High quality uni can be worth as much as $80 or more per pound. The fishery in Maine peaked in 1993 at around 40 million lbs. and employed over 1,800 people; by 2009 less than 5 million lbs. were harvested.
  • 2010 Dock prices for whole urchins exceeded $5/lb. during peak demand. Farming methods include sea ranching, cage systems, and land based tank farms. Urchin gonad bulking, holding for harvest on demand, and value added processing are all ways to optimize a limited resource.
  • The harmful effects of sea urchins to the marine communities called for a reduction in their numbers.

Entrepreneur who want the information such as "General, Facts, Project, Fertilisation, Development, Recipe, Suppliers, Product, Farming, Consultancy, Reports, MSDS, Study" about Sea urchin can email us to,

Primary Information Services
 21 Murugappan St, SwamyNagar Ext2, 
Ullagaram, Chennai - 600091, India.
 Phone: 91 44 22421080 
Email :,
Mobile numbers:9940043898, 9444008898  Fax : 91 44 22423753