Why Reefs Matter

Last Updated: 24 July 2008

A hawkfish explores branching coral. [Supplied, Chuck Savall]

A hawkfish explores branching coral. [Supplied, Chuck Savall]

The beautiful underwater landscape of a healthy coral reef is an unforgettable sight. The colourful gardens of delicate fronds, ridged boulders and broad dinner plates are home to thousands of fish, crabs and other marine life, many of them just as brilliantly coloured.

But as the earth's climate changes, the oceans are warming up and becoming more acidic. Cities and towns pump sewage and industrial pollution into the seas, and soil from land-clearing and erosion is also going into the ocean. As a result, the world's reefs are slowly dying, with huge implications for the estimated 400 million people worldwide who rely on coral reefs for their food, income, and homes.

Every four years, the latest reef research is presented at the International Coral Reef Symposium. At this year's meeting in Florida, nearly 3,000 scientists and conservationists met to look at what's happening to the world's reefs, and how they might be saved from extinction. Radio Australia's Corinne Podger was there.

Hundreds of coral species face extinction

A landmark global survey of coral reefs released this month found a third of all coral species are at risk of extinction.

Carried out by an international team of scientists, the survey was published in the prestigious journal, Science and announced at the recent International Coral Reef Symposium in Florida.

As Corinne Podger reports, the findings mean that coral reefs have joined the unenviable ranks of life forms most likely to vanish permanently from the earth.

Can corals adapt to global warming?

The latest research on the effects of climate change on coral reefs suggests rising temperatures and changes in ocean chemistry could kill off many of the world's reefs within 50 years.

In a series of presentations at the recent International Coral Reef Symposium in the United States, scientists from Australia and the US rejected previous reports that reef systems might adapt to the amount of carbon dioxide being absorbed by the world's oceans.

They say CO2 levels are rapidly approaching a critical limit, beyond which reef systems simply won't survive, as Corinne Podger reports.

Caught on film - the best approaches to saving reefs

Participants at the recent International Coral Reef Symposium agreed that a major challenge for reef conservationists is the sharing of effective techniques and practices.

If any reefs are to survive the impact of climate change, the symposium heard, they need as few other forms of stress as possible.

That means cutting back pollution from soil run-off and sewage, and for local communities to move away from destructive fishing methods like trawl nets, dynamite and poison.

Corinne Podger spoke to representatives from Pacific island NGOs, who're using video to share good ideas on reef management between countries separated by thousands of kilometres of ocean.

Hidden overfishing threatens Pacific food security

A new study by the Canadian research organisation, The Sea Around Us, has found fish catches from Pacific island nations are vastly under-reported. The research was presented at the recent International Coral Reef Symposium in Florida, and covers half a century of fishing - from 1950 to 2004 - in 20 island nations.

The researchers say that in some cases, unreported catches by local fishing communities are nearly 20 times higher than the official statistics collected by governments and handed to the Food and Agricultural Organisation.

They say the findings have worrying implications for regional food security, as Corinne Podger reports.