Marine heat waves:Coral reefs in Sri Lankan waters risk die-offs

• If the temperature fluctuates between 27-28 degrees Celsius, it will be conducive for coral health. However, if the current high temperature persists for another one month or so, coral deaths can be expected

By Kelum Bandara  
Coral reefs in the sea around Sri Lanka risk die-offs if the current marine heat level persists for another one month or so, a top scientist said yesterday.  
The Indian media reported that an alarming situation of severe coral bleaching had been reported in the Lakshadweep Sea and the Gulf of Mannar.   

Asked for a comment in this regard, newly appointed Director General of the National Aquatic Resources Research and Development Agency (NARA) Dr. K.Arulananthan told Daily Mirror the heat level had increased to 31 degrees Celsius and remained for two weeks.  
He said NARA did not carry out any inspection on the status of coral reefs in the island waters but bleaching could not be ruled out.  
“If the heat level fluctuates between 27-28 degrees Celsius, it will be alright for coral health. However, if the current high level persists for another one month or so, coral deaths can be expected,” he said.   
Marine heat waves are rare extreme weather events that involve prolonged periods of abnormally high ocean temperatures.  
Coral bleaching occurs when the temperature of the water rises above normal levels. Under such conditions, corals expel the microscopic algae living in their tissues, which are responsible for providing them with nutrients. Dozens of types of algae live inside corals in a mutually beneficial relationship that gives the corals colour, nutrition and slight changes in water composition that help make its limestone skeleton.