PETALING JAYA - Coral reefs in Malaysia’s Island Marine Parks, mainly off the peninsula, are starting to see the onset of bleaching, a consequence of the intense heat and the rapidly warming ocean as El Nino looms.

The Malaysian government said it has been monitoring its coral reefs and if the sea surface temperatures remain high in the next few weeks, they will start to bleach.

“We have noticed that the US National Oceanic and Atmospheric Administration (NOAA) Coral Watch Programme has issued a ‘Bleaching Watch’ alert for Island Marine Park Malaysia in May 2023,” Fisheries Department director-general Adnan Hussain said in a reply to queries from The Star newspaper.

“This notification indicates that sea surface temperatures around Malaysia are above normal temperature of 28 deg C – 29 deg C, and that coral bleaching is a possibility if conditions do not return to normal within a few weeks.”

Datuk Adnan said Malaysia had set up the Malaysian Coral Reef Bleaching Advisory Panel and the Coral Reef Bleaching Response Committee following a mass coral bleaching event in 2010. It also published the Coral Reef Bleaching Response Plan to respond to future bleaching events.

“The Bleaching Response Committee has begun surveys of coral reefs since March 2023 to monitor the situation in the country, and track the onset of any bleaching. The current data showed that reefs in Payar Island Marine Park, Kedah; Redang Island, Terengganu; Tioman Island Marine Park, Pahang; and the Aur Island Marine Park, Johor are under thermal stress with sea surface temperature reading of 28 deg C to 29 deg C,” he said.

“A few dive sites in Tioman Island Marine Park has shown early signs of bleaching. Action plans to respond to such an event have already been prepared.”

Parts of South-east Asia, including Malaysia, have been gripped by a heatwave, with countries charting record high temperatures like Vietnam at 44.1 deg C, Singapore at 37 deg C, and Thailand at 41 deg C.

On May 13, MetMalaysia issued level 1 heat wave warnings for 31 districts in the country. It was reported in April that preliminary data from the NOAA showed the average temperature at the ocean’s surface has been at 21.1 deg C since the start of April – beating the previous high of 21 deg C set in 2016.

Mr Adnan said the Committee will provide further information as it becomes available, and will communicate accordingly to ensure that all stakeholders are kept fully informed of the changing situation.

The Advisory Panel, which is responsible for supervising the overall implementation of the Coral Bleaching Response Plan, is represented by various relevant federal agencies, state agencies, NGOs and Local Universities.

The Bleaching Response Committee, which acts as a working committee to implement the response plan, is represented by the Fisheries Department, Sabah Parks, Sarawak Forestry Corporation, Reef Check Malaysia and Universiti Kebangsaan Malaysia (UKM).

“The Advisory Panel and the Response Committee are monitoring the situation and consulting with stakeholders to develop appropriate management responses, in order to protect Malaysia’s valuable coral reefs,” he said.

Coral bleaching, Mr Adnan said, posed a major threat to the health of coral reefs and deserved serious attention due to the implications for marine biodiversity, coral reef fisheries and tourism in Malaysia.

Bleaching is a natural response of corals that are under stress, he said, adding that a sustained rise in seawater temperature is one of the most common reasons for mass coral bleaching.

“The term ‘mass bleaching’ describes the large-scale phenomenon of many species of corals bleaching simultaneously over a significant spatial scale. The previous record of mass bleaching in Malaysia was in 2010 at the Marine Park Malaysia,” he said. “Our reefs suffered between 5 per cent and 10 per cent of damage during the bleaching event.”

He said reefs in Malaysian waters had begun to recuperate to its healthy status before the 2010 bleaching event through various conservation efforts by agencies, local island communities, NGOs and corporate organisations.

As at May 15, the stations in Malacca Strait, Terengganu, Johor and Pahang, Sabah and Northern Borneo were all showing the orange bleaching warning on the NOAA website. The station in southern Borneo is showing the red Bleaching Alert Level 1. Also showing warning for bleaching are the stations near to Malaysia, such as those in Singapore Strait, South-western Thailand, and the waters off Brunei and Southern Philippines.

The NOAA’s Coral Reef Watch Programme publishes satellite data on sea surface temperatures, providing an indication of current reef environmental conditions to quickly identify areas at risk of coral bleaching. Reef Check Malaysia general manager Julian Hyde said they were starting to see the onset of bleaching.

“The first signs are apparent now – corals are paler than normal. This is the early stages of bleaching and if water temperature remains high (it is already 30-32 deg C, which is above the usual 28-29 deg C), then full bleaching could happen, possibly on a wide scale,” he said in an interview.

When corals are stressed by changes in conditions such as warmer water temperatures, they expel the symbiotic algae living in their tissues, causing them to turn completely white. Prolonged bleaching can cause corals to die from starvation. Besides being an attraction for divers, coral reefs act as a habitat for many marine species.

“If the corals die, the reef will slowly degrade and all those habitats will disappear, and the population of those other species will also decline” said Mr Hyde.

He said its own staff were monitoring the situation closely, and it was also asking other divers to report if they see anything. “Right now, all we can do is monitor how quickly bleaching happens, and then how long it lasts, and eventually whether any corals die.”

He said in reality, bleaching cannot be stopped once it has started .“We can’t do anything about the warm water. About all we can do is reduce other threats as much as possible to give coral the best chance to recover,” he said. “This might include closing key reef areas to diving and snorkelling to reduce physical impacts.”

Other measures are improving waste management to reduce physical impacts from rubbish, ensuring enforcement to prevent fishing in reef areas, and controlling coral predators.

Mr Adnan said continuous monitoring of sea surface temperature at global scales provides researchers and stakeholders with tools to understand and better manage the complex interactions leading to coral bleaching.

“When bleaching conditions occur, these tools can be used to trigger bleaching response plans and support appropriate management decisions,” he said. THE STAR/ASIA NEWS NETWORK