Coral reefs provide food, fishing income, and protection of the land from large storm waves. As most of Fiji’s tourism is based on the coast and around the coral reefs, for many Fijian people the reef is also a source of employment. If the reefs are dead or in poor health, there are fewer fish, fewer jobs, and more coastal erosion.
Coral Reefs are the oldest, most complex ecosystems on earth. They are home to more kinds of life than any other ocean environment, and rival the tropical rainforests on land. They have existed for well over 50 million years.
Corals are small animals (polyps) that are closely related to sea anemones and jellyfish. Most corals create colonies, by growing a large rocky skeleton that we see as a solid coral rock. The soft bodied polyps live in the outer edge of this skeleton, on top of the empty skeletons of previous generations. Only the outer layer of a coral boulder is alive.
Hard corals come in a variety of shapes, sizes and colours. The most common are Branching, Boulder, Leafy, Finger, Mushroom, Encrusting and Table. As a basic rule of thumb if coral is coloured it is alive. Dead coral is white or grey.
Water Quality
Corals need clear, clean, nutrient-free waters and temperatures between 21 and 32oC to live in.
The two main nutrients which cause problems for the reef are called Nitrate and Phosphate. These are found in spray fertilisers, waste from human toilet systems, pig farms, and detergents used in kitchens and laundries.
If the sea water has too many of these nutrients, corals cannot make their hard rocky skeletons, and seaweeds (algae) grow faster than corals and block out the sunlight, so that the corals die.
In areas with polluted water, the reef changes from a colourful, coral-rich area supporting many fish and other animals, to a flat, brown plain covered in seaweeds, where there are very few fish and animals. Also, such areas do not protect the shore during large storms, and so these areas can suffer coastal erosion and loss of beach and land.
How can Fiji’s people help keep Fiji’s water clean?
Make sure that all toilets go into proper septic or other treatment systems
Do not build piggeries directly over streams that run into the sea
Reduce use of spray fertilisers and weed-killers on fields and plantations
Use biodegradable low phosphate or phosphate-free detergents
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