Coral: Rock, Plant, or Animal

     Everyone has heard of coral reefs, but what exactly is a coral? A coral is part animal, part plant, and part rock.
     Coral animals are small polyps that build calcium carbonate skeletons around themselves. This gives the coral it's shape as many polyps join the community and create the rocky calcium structure. Most corals have a plant component in the form of zooxanthellae. The coral and zooxanthellae form a symbiotic relationship, meaning that they both are benefitted by maintaining their bond. The coral receives nutrition from the zooxanthellae and the zooxanthellae is protected by the coral. If the waters become too warm for the zooxanthellae to survive, they leave their coral partners. The coral then dies as a result, a phenomenon called bleaching. Unfortunately, bleaching is occurring at a more rapid rate than expected due to warming ocean temperatures.

    During our dives today, our group saw many different forms of corals, including brain, staghorn, and finger corals. These different forms of corals provide wonderful habitat for many different types of fish, which is why coral reefs are very diverse. Our dive revealed many fish staying close to the corals, such as bluehead wrasse and fairy basslets.This provides them protection from predator species. Some fish even eat the corals directly. Parrotfish are one such fish, using their beak-like mouths to take bites of the hard coal skeleton. In addition, animals that eat coral reef fish congregate near the reefs, such as the nurse shark seen on today's dive.

     The coral reef habitat is extremely important for many populations of animals. However, corals are fragile and slow growing, so damage to the corals can alter the entire environment. Boats  can cause coral damage while anchoring or running aground and human tourists can harm corals by stepping on them or breaking off pieces. In order to combat this damage, some organizations grow corals and place them on the reefs to restore the reef community.
    To learn more about an organization that helpts to restore coral reefs, click here.
    If you're interested in going on a dive to see the corals for yourself, check out Captain Slate's Scuba Adventures.