Hobbies And Interests
Habitat
Sea urchins and kelp inhabit shallow, rocky coastal waters. They are both benthic organisms that live on the hard ocean floor. Kelp and sea urchins are connected because they are both important to the ecosystem of the coastal waters. The kelp attach to the ocean floor and grow upward creating dense kelp forests, which provides both protection and habitat for more than 800 species of marine organisms. The sea urchins are important because they graze on marine algae in the coastal waters and are a food source for animals living in the kelp forests.
Sea Urchins and Kelp Forests
Sea urchins, Stronglyocentrotus species, play an important role in the stability of kelp forest ecosystems as urchins graze on kelp as their primary food source and they inhabit the ocean floor where kelp attaches. Sea urchins are sedentary animals that live on the ocean floor in both tidal and littoral regions where kelp forests form. The urchins move along the ocean floor grazing and destroying kelp forests. Studies were conducted over a ten year period to survey kelp forest density and sea urchin biomass. These studies were conducted on Adak Island. The research found that kelp density decreased by up to 47.5% per day as a result of sea urchin grazing.
Urchin Barrens
Sea urchins can graze on up to 30 feet of kelp per month, creating a barren ocean floor. The sea urchins multiply in number and remain in herds in these barren regions, preventing the kelp forests from re-growing. A decrease in kelp forests results in a decrease in populations of other species of animals that depend on the kelp forest for food and shelter.
Sea Otters
Sea otters have become a key component to kelp forest restoration since sea otters hunt in kelp forests and feed primarily on sea urchins. Sea otters feeding on sea urchins decreases the number of urchins that can graze kelp forests and form urchin barrens. There have been efforts made to specifically relocate sea otters to areas where kelp beds are being destroyed by sea urchins.