Mass coral bleaching expected in Mar-May 2027

Mass coral bleaching is likely in Singapore in Mar-May 2027. NParks will be monitoring.

Mass coral bleaching at Kusu Island, Jun 2024

Karenne Tun, group director of NParks’ National Biodiversity Centre said that while recent studies show that repeated bleaching in Singapore has caused relatively low immediate coral death – usually under 10%, and about 5% in the 2024 bleaching event – the reefs are changing and have “flattened” over time. Repeated bleaching and shifts to simpler reefs may affect coral spawning, limiting the  reefs’ long-term resilience even if they appear to recover.

Marine biologist Huang Danwei, deputy head of NUS’ Lee Kong Chian Natural History Museum noted that increased frequency of coral bleaching events means reefs have less time to recover between them. When corals do not recover, the flora and fauna that depend on reef habitats also decline in abundance and diversity.

According to third World Ocean Assessment: “The reefs of today will not be the reefs of tomorrow, and shifting baselines need to be considered when setting objectives, with respect to conservation, restoration and regeneration".

Current efforts include NParks’ 100k Corals Initiative, launched in December 2024 to plant 100,000 corals in Singapore over the next decade and beyond. It is the most extensive coral restoration effort in Singapore to date. Jani Tanzil, facility director of the St John’s Island National Marine Laboratory, noted that in Singapore’s case, where only about 10 sq km of reefs remain, there is no choice but to turn to this last resort of reef restoration to combat their decline.

Long Island: NParks to study fish on reclaimed shores

As preparatory works for the Long Island start in end-2026, NParks announced a study of fish on reclaimed shores. Initiated in 2025, expected to span 3 years, official start date not revealed. 

HDB said “Given the mobility of fish and the availability of habitats outside of the work areas (of the Long Island preparatory works), the impact on fish is assessed to be temporary and localised.”

Lee Kong Chian Natural History Museum's senior collection manager of fishes Tan Heok Hui said there will not be enough time for the NParks study to document comprehensively the existing biodiversity at Bedok Jetty. He noted no proper baseline surveys currently exist for the East Coast area. And existing impact assessments often overlook less mobile, bottom-dwelling or burrowing organisms. Because the entire East Coast is already on reclaimed land, it is technically considered of lower ecological importance compared with pristine marine habitats. 

Four anglers in their 20s formed a fish interest group to document the species at fishing hot spot Bedok Jetty before works start. Student Lin Jiayuan, 24, and three of his friends founded the Ichthyological Society of Singapore on July 6. The group, which has grown to more than 80 members, aims to document the biodiversity that remains along the Republic’s rapidly developing coastlines.

Sentosa Tg Rimau: EIA on slope stabilisation works

Work will begin in 2027 across a 400m stretch of Sentosa Tanjong Rimau. This include "a few hundred XblocPlus blocks, each weighing about a tonne, to be placed at three sites". The EIA found that more than 12 per cent of seagrass meadows may be lost. Soft, sandy and seagrass habitats are likely to transform into artificial hard, rocky habitats at the locations of the XblocPlus.

Muhammad Nasry Abdul Nasir, executive director of Singapore Youth Voices for Biodiversity said: “If you’re protecting an existing seawall or a reclaimed shoreline with little ecological value, (adding XblocPlus) for habitat complexity is a no brainer. But Rimau is not a blank canvas; there’s a lot of life there. Are there alternatives we can consider that are less drastic in terms of reshaping the shore, that can still provide the coastal resilience we are looking for?”

“While stabilising the slopes is necessary to prevent progressive collapse (of the cliff), the approach should minimise impacts to Tanjong Rimau’s biodiversity,” said Lester Tan, chairman of Nature Society Singapore’s Marine Conservation Group. “I’m always in favour of not changing one habitat to another. There could be a loss of connectivity,”

Read the full EIA on the Sentosa website.

Send your feedback here https://form.gov.sg/6a20d00d14f841cbd5b20469

Related blog post: Sentosa Tg. Rimau: Interlocking 1-tonne blocks to be deployed

Terumbu Semakau next to massive worksite

A large team surveys this large submerged reef next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom. There is currently a large worksite near it for repairs to the pipeline carrying crude oil to Pulau Bukom.

We still find rich reefs at the edge facing the Landfill, but elsewhere, less corals. The water seems a bit more murky that usual and sand seems to have built up on some parts of the shore. But two Giant clams are found, and the rest of the team make special finds which I will update later.

Terumbu Hantu in the face of Sudong reclamation

Despite being next to petrochemical plants on Pulau Bukom and surrounded by heavy vessel parking, this little gem with rich reefs is one of our favourite sites.

Today we survey within sight of the ongoing massive reclamation on Pulau Sudong. We are relieved to see the corals are still doing well. The rest of the team make all the special finds, I will update later.

Kusu Island still reefy, with Giant clams!

This rich reefs of Kusu Island lies just opposite the Central Business District, less than half an hour away by fast boat. A small team surveys the rich reefs that are now part of Singapore's second national Marine Park at Lazarus South-Kusu Reef. 

The corals are slowly recovering from the 2024 mass coral bleaching and we feel haven't quite returned to their former glory. This is quite worrying as we are expecting another round of mass coral bleaching next year. We also saw 3 giant clams and other fascinating finds. I will compile the rest of the team's finds later.