Indo-Pacific corals more resilient than Caribbean twins
Sydney: Corals of the Great Barrier Reef in Australia and Indo-Pacific region recover faster from stress than their Caribbean counterparts, say marine scientists.
"The main reason for this phenomenon is that Indo-Pacific reefs have less seaweeds than the Caribbean Sea," said George Roff from the ARC Centre of Excellence for Coral Reef Studies, Australia.
The study includes survey data from the Indo-Pacific region and Caribbean reefs from 1965 to 2010, the journal Trends in Ecology and Evolution (TREE), reports.
"Seaweeds and corals are age-old competitors in the battle for space. When seaweed growth rates are lower, such as in the Indo-Pacific region, the reefs recover faster from setbacks," said Roff, according to an ARC Centre statement.
"This provides coral with a competitive advantage over seaweed, and our study suggests that these reefs would have to be heavily degraded for seaweeds to take over," added Roff.
"This doesn't mean that we can be complacent - reefs around the world are still heavily threatened by climate change and human activities," he says.
"What it indicates is that Indo-Pacific reefs will respond better to protection, and steps we take to keep them healthy have a better chance of succeeding," said Roff.
"Many of the doom and gloom stories have emanated from the Caribbean, which has deteriorated rapidly in the last 30 years," said Peter Mumby, professor at the University of Queensland.
"We now appreciate that the Indo-Pacific and Caribbean are far more different than we thought."
The researchers also found that seaweeds in Indo-Pacific region bloom four times more slowly than those in the Caribbean.
"We're not sure why this happens, but a plausible theory is that Caribbean waters are highly enriched in iron," Mumby said.
"For thousands of years, the Caribbean Sea has received dusts that blow across the Atlantic from the Sahara, and the dust contains iron - an essential element for algae to grow, the researcher added.
"This suggests that the difference between the Indo-Pacific and Caribbean oceans and their coral reefs is fundamental, and occurs at a very large scale," Mumby said.
These findings were presented at the 12th International Coral Reef Symposium in Cairns, Australia.