Global warming is being blamed for coral bleaching along the Cobourg Peninsula in the Northern Territory.
Water temperatures have risen more than 4 degrees and Ms Adele Pedder from the Australian Marine Conservation Society says further reef devastation is expected due to climate change.
Entire ecosystems are dependant on the reef and are threatened by coral bleaching.
The Northern Territory and Federal governments are being called on to improve coastal management to reduce to reduce stress on the reef.