Purple Sea Urchin Food

There are many different species of sea urchins. The purple sea urchin's scientific name is Strongylocentrotus purpuratus. It has a spine and spikes that it uses for protection and movement, according to the Tree of Life Web Project. Their feet are tube-shaped to help them move. They play an important role in keeping the algae levels of the ocean under control, according to the Tree of Life Web Project.

  1. Habitat

    • They live in shallow waters along the Alaskan coastline and "down the Pacific Coast to Mexico," according to the Tree of Life Web Project. Sea urchins cannot survive in fresh water areas, according to Stanford. They inhabit areas with strong waves, according to The Tree of Life Web Project. Purple sea urchins live in kelp forests, as one of the main sources of their food is kelp.

    Food

    • Sea urchins eat seaweed, according to Stanford. They also eat meat, which includes eating each other. The purple sea urchin has a mouth with five teeth located underneath its body, which makes it easy for it to eat kelp and other seaweeds. The teeth are known as "Aristotle's lantern," according to Monterey Bay Aquarium. The waste that a purple sea urchin produces goes out the top; the mouth is on its bottom.

    Finding Food

    • Sea urchins are nocturnal. They search for food at night, and stay stationary during the day. One of the strategies that sea urchins use to trap their food is by hanging out in a rock burrow until the seaweed they are after comes to them, according to Stanford. Another strategy they use is to head straight for their prey once they have found it by smelling it.

    Predators

    • Inside the ocean there are sea otters, and starfish that eat urchins, while outside of the water there are humans and seagulls that stalk sea urchins, according to Stanford. Humans are the biggest threat to sea urchins as people in places such as Japan have a large market for them, according to Stanford. Sea urchins protect themselves from their predators by hiding under shells and rocks that they pile on top of themselves.

    Importance

    • The purple sea urchin plays an important role in the ecosystem. The fact that they eat algae means that they maintain healthy algae levels in the areas that they populate, according to the Tree of Life Web Project.