Climate change is the biggest threat to the Great Barrier Reef, officials said yesterday on the heels of a report that also found some of Australia's other unique flora and fauna are being negatively affected by the changing environment.

The independent government-commissioned report found shearwater seabirds are reproducing less because of higher sea temperatures; the population of the mountain pygmy possum is vulnerable to drought and new predators as its snow cover melts away earlier in the year; and eucalyptus trees in Tasmania are dying off because of a continuing lack of rain.

The findings were worrying because Australia is one of world's most biologically diverse countries. Up to 80 percent of its plants and animals are found nowhere else.

"This report reinforces what we already know - that our birds and animals and their native habitat is threatened by climate change and the rate of extinction is likely to increase unless we take action," Environment Minister Peter Garrett said at an ecology conference in Brisbane.

Great Barrier Reef Marine Park Authority Chairman Russell Reichelt said officials were launching a new plan to raise awareness of the impact of weather and humans on the famous marine habitat. The study found mass coral bleaching events continue.

Coral bleaching is caused by warmer waters, which cause the stressed organisms to expel colorful algae living in their tissues, leaving a whitish color. Coral bleaching that lasts more than a week can kill the organisms.