Recovery at Sentosa Serapong

One of the best reefs nearer the mainland is found on the undisturbed shore off Serapong Golf Course at Sentosa. We visited at the beginning of last year's mass coral bleaching and estimate about 10% of corals were outright bleaching. Our visit was before the 400tonne Pasir Panjang oil spill on 14 Jun 2024 and the 23 tonne diesel leak opposite Sentosa Serapong on 5 Feb 2025.

I am relieved there was no longer any bleaching. Although there was much coral death, there were also signs of recovery. Thank you SDC and Serapong Golf Course for supporting our annual surveys and for looking after these precious shores!

The rest of the team spot a variety of fishes! The star find was a small seahorse! They also spot the Tomato anemonefish and also many Common anemonefish. Plus an Estuarine moray eel, small grouper, large rabbitfish, many different kinds of butterflyfishes (just glimpses in murky water), and even a shrimp-goby. There were many Blue-spotted fantail rays. 

Photos by the team.
Links to their albums at the end of this post.

Kelvin shared a video of a shark peacefully foraging on the reef edge. We commonly encounter wild sharks on our reefs. They will often hunt for fish in shallow water in the outgoing and incoming tide. If we stay still and quietly observe it can even come close. But as soon as the shark detects us, it will often U-turn and swim away. Sharks will not harm humans if we do not disturb them.

The rest of the team also check up on the Fluted giant clam (nearly 40cm long) and it was fine! They also spot many colourful nudibranchs, including the very large (for a nudi) Ceratosoma nudibranch. They also saw large clusters of Magnificent anemones, as well as for the first time, 2 Haeckel's anemones. There was also Fire anemone, Haddon's carpet anemone and many Giant carpet anemones. The most abundant echinoderm on the shore remains Red feather stars which hang onto corals at the reef edge. The team also spot Black and Brown feather stars among them.

Collage of photos by the team.
Links to their albums below.

The area between the beacon and the sluice gate still has a patch of densely packed leathery soft coral colonies. Pretty much like what I saw when we first started surveying the shore.

There are still some clusters of leathery soft corals all along the shoreline. Towards the Jetty, there were lots of Spiky flowery soft corals and Asparagus flowery soft coral. I also saw 3 Leathery sea fans. All of them seemed alright. 

The enormous leathery soft coral colony that we have been seeing since we first started surveying the shore is still there. Seems a little larger, and is no longer bleachy, as it was last year. It has however, split up into smaller pieces since last year - this animals does it when it is stressed, possibly for better chance of at least some pieces surviving the stress. Much nostalgia looking at the photo of Sheila from Serapong Golf Club (who first facilitated our surveys) and Shao Wei from SDC (who supported our work) nearly ten years ago, with the same leathery soft coral!

I do sense there are much fewer live corals along the shoreline. Most of the corals were common boulder shaped ones.

The big 'Table Coral' Acropora in front of the sluice gate is stone cold dead and mostly covered in blue sponges and other encrusting animals. But small brown healthy Acropora colonies are sprouting from the dead base. In the photo, what the colony looked like over the years. Hopefully, it can recover to its original glory. None of us could find the even larger colony near the Beacon, possibly because the tide was not very low. During our May 2024 survey, the colony was pale but not yet bleaching.

The cluster of Branching montipora in front of the sluice gate is mostly dead, but there are quite a few healthy colonies on the seaward side. There were also sprinkles of this hardy coral growing all along the shoreline. Not forming dense fields, yet?

There were still many large colonies of Anemone corals, some even quite close to the seawall. Some were mostly dead with only about 20 live corals on the outer margins. Others were mostly alive.

There were also a few special corals like Anchor corals. The Ridged monitopora corals near the jetty were mostly still alright and festooned with Red feather stars as usual. There were a few Cauliflower corals and Sandpaper corals, all looking okay. The plate forming corals were also fine, with some huge colonies still looking good.

Some of the team revisit the corals past the jetty towards the causeway bridge at Sentosa, that Kok Sheng saw on our last survey in May 2024. They saw some special corals, including mushroom corals. It seems some of the large colonies are still there.

Collage of photos by the team.
Links to their albums below.

In 2018, we observed mass dying at Serapong, and only at Serapong - cause still unknown. Many corals hard and soft, as well as large sponges were dying. We observed a somewhat full recovery during our last survey in May 2023. Today, it was great to see some medium-sized to large healthy Barrel sponges - these suffered badly during the Big Dying. I also saw a Giant carpet anemone with about 6 'Nemo's! There were also many Diadema sea urchins throughout the reef edge. 

Tammy shared a small patch of Spoon seagrass with large leaves past the jetty. Between the Beacon and the jetty, I only saw a few clumps of Tape seagrass with long leaves, one had female flowers. The small patch of Sickle seagrass near the beacon seems more sparse than before.

Photos by the team on the survey

Kelvin Yong


Che Cheng Neo

Adriane Lee


Tammy Lim


Tommy Tan


Lon Voon Ong


Others on this survey: Muhd Nasry, Isaac.