Conserving Biodiversity on Coral Reefs

Points covered:

• Where are coral reefs most diverse?
• What is the importance of biodiversity in the conservation of coral reefs?
• What is the importance of conserving reef habitats?

Coral reefs are among the most diverse ecosystems on earth. However, coral reefs in different parts of the world support different levels of biodiversity. The greatest coral reef diversity is found in the region where the Indian and Pacific Oceans meet. The number of most coral reef plant and animal species declines as the reefs get further from this spot. For example, there are more than 400 species of hard corals in the Philippines, about 350 in the northern Great Barrier Reef, about 250 in Fiji and less than 50 species in Hawaii. The Caribbean boasts the highest coral reef diversity in the Atlantic Ocean, but this is only equivalent to the least diverse regions of the Indo-Pacific.

As with other environments, the key to conserving biodiversity on coral reefs is conserving the habitat. In the coral reef environment, the most important habitat feature is good water quality. If this can be maintained, conservation of many other important habitat features will follow. Our developing knowledge of the larval behaviour of reef fishes may, one day, allow for the re-seeding of reefs depleted by overfishing. However, unless those reefs have good water quality and provide the shelter and food needed by fish species at all stages of their life cycle, re-seeding will not be successful. Coral reefs, and the enormous number of species that live on and in them, need warm, unpolluted seawater and plenty of light.

On the Great Barrier Reef, as on most coral reefs, scientists are continually discovering new species of fish, corals, worms and other living things. Many of these organisms play important roles in the overall health and functioning of reef ecosystems. Scientific research into the biodiversity of coral reefs contributes greatly to the future conservation of this reef.

As well as being the largest coral reef system in the world, the Great Barrier Reef is also the best managed. As a result, it has the best chance of maintaining its biodiversity in the next century. Many reef systems around the world are being degraded at an alarming rate, so conserving the Great Barrier Reef is a worthwhile challenge.

Anne Hoggett
Lizard Island Research Station