The aquatic life on the Great Barrier Reef is a complex system of plants, bacteria and animals. It is the diversity of life forms which construct their own habitat and provide the food supply for all the reef community.

As such each of these life forms is active in the development and regeneration of their environment thus enabling the system to become self sufficient like an enormous, natural 'perpetual motion machine'.

The astounding variety in colour, form and behaviour of fish on the reef seems at first glance to be just there for us to enjoy but, of course, there is a good reason for all this magnificence. Colours are used by some to warn off predators while others use colour for camouflage. Form is often used for camouflage, too, and many fish have adopted behavioural patterns which allow them to be safe in an otherwise dangerous environment.

Master builders of the Great Barrier Reef

The builders of this enormous construction are in fact the tiniest of animals. These creatures are called coral polyps which build skeletons of limestone and create the living structure called coral colonies. These colonies provide the framework in which a vast variety of marine life abounds. Out of about 400 species of corals, 350 are ‘hard’ corals and are responsible for the building of the Reef while the remainder are ‘soft’ corals which are mostly non-skeleton builders.

Layers of limestone are laid down by colonies of hard coral with polyps moving up to the new layer. The rate of growth varies amongst the species between 1 centimetre and 10 centimetres per year. Therefore, any damage done to the reef by either nature or human would take untold years to repair.

How does a Coral Reef grow • Description of Reefs and Islands • Aquatic Life • Back to the Bunker Group