Coral reefs are the most biodiverse spots in the sea, hosting up to two million species in their colourful sprawl. Image Credit: Supplied

ABU DHABI: Over 73 per cent of coral reefs in the UAE have been wiped out due to bleaching, according to studies conducted by New York University Abu Dhabi (NYUAD) in collaboration with Emirates Environmental Agency (EEA).

Coral bleaching is a phenomenon where coral reefs turn white due to exposure to high water temperature and other local impacts like sewage, overfishing, sedimentation, dredging and construction. Reefs located in warm, shallow water with low water flow are more prone to bleaching than those with higher water flow.

John Burt, associate professor of biology and head of the marine lab at NYUAD said the worst recorded coral bleaching event in the region took place last year, stretching over 200 kilometres across UAE, Kuwait and Saudi Arabia.

Nearly three fourths of our coral reefs were destroyed. But Kuwait and Saudi Arabia were the worst hit, losing 90 per cent of their reefs.

The Arabian Gulf is ideal for reef-building corals and substantial reefs have formed along the coast of the UAE, particularly along Abu Dhabi due to its shallow, calcium carbonate-rich waters.

 

Causes for bleaching

“Coral bleaching take place because of manmade conditions and global warming. Human activity like dredging, reclamation and overfishing and high water temperatures have negatively impacted our reefs. In the last decade we have seen water temperatures rise almost every year. This is taking a toll on the reefs,” said Burt. He also called for a ban on landfills and reclamations near coral reefs.

 

How the degradation happens

“Corals live in symbiosis with algae which grow inside their tissues. When the water temperature goes up, the algae gets expelled from the coral tissues, burning reefs and turning them white.

Burt said the Gulf waters have seen many bleaching events in the past. “But the worst was last year when we had one of the hottest summers. We had a period of over five weeks with little wind, causing water temperatures to soar. This resulted in massive coral reef destruction.

 

Why are coral reefs important

“Coral reefs provide habitat and shelter for marine organisms. They protect the coastline from erosions due to external environmental factors. So it’s very important to protect them. More than 20 sites in the UAE have already been designated as marine protected areas.

 

Recovery time

“Corals take time to recover after bleaching. A team of experts are monitoring them. We are also trying to reduce the amount of dredging and reclamation in and around UAE coastal areas,” he said ahead of upcoming (November 5-) Gulf 3 International Conference in Al Ain where the study will be presented.