Coral bleaching in India-Sri Lanka: Corals on decline in Gulf of Mannar

S M Arun Express News Service 24 Oct 10;

THOOTHUKUDI: Corals in the Gulf of Mannar may soon be a thing of the past if the current die-off trend continues.

A reef research team from the Suganthi Devadason Marine Research Institute (SDMRI) in Thoothukudi recorded coral mortality this October — a first since 2002 — during a meticulous rapid monitoring in the Gulf of Mannar.

The reputable research institution has regularly been monitoring coral reef in the Gulf of Mannar since 2005 after developing a baseline on coral status here during 2003-2005.

According to the director of the institute, Dr J K Patterson Edward, mass bleaching and coral mortality were earlier witnessed in 1998 and 2002.

Explaining the phenomenon of bleaching and mortality, Edward said coral bleaching occurs when the water temperature reaches 31ºC in mid-April every year in the Gulf of Mannar and recovery is usually recorded in June-July, depending on rainfall and winds.

“In 2010, we found that due to the elevated temperature (32.2-33.2ºC), which prolonged for four months (April to July), recovery could not take place,” he said.

He pointed out that due to this six to eight per cent of live coral in the Gulf of Mannar had died and since most are covered with turf algae, chances of recovery were slim.

Interestingly, live coral cover in the Gulf of Mannar increased from 37 per cent in 2005 to 42.85 per cent in 2009, which according to Edward had been due to the proactive measures of the government.

According to the data provided by SDMRI, the average percentage of bleached corals during 2005, 2006, 2007, 2008, 2009 and 2010 was 14.6, 15.6, 12.9, 10.5, 8.93 and 9.01, respectively.

Edward called for eco-friendly fishing and support for protection measures by the park management to save the coral reef. The SDMRI, an acclaimed underwater research institution in India, is one of the five institutions identified by the Government of India for environmental monitoring of the Sethusamudram Shipping Canal Project.