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 Semakau after a storm - still okay!

Plunging headlong into a Sumatras storm, a small team emerges on the other side of the storm front to survey this special submerged reef. It lies right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom, less than an hour away from the Central Business District. 

Photo by Liz Lim

It was a relief to see that the reefs seem to have pulled through the Fourth Global mass coral bleaching event last year. We were last here in Aug 2024 when we estimate about 10% of hard and soft corals were bleaching. Today, there were no widespread signs of bleaching.

Mass coral bleaching at Terumbu Semakau

A small team returns to this submerged reef lies right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom, and less than an hour away from the Central Business District.

We return to check on the impact of mass coral bleaching here. We estimate only about 10% of hard and soft corals were bleaching. The big anemones and other cnidarians were fine. The seagrass situation seems unchanged, and the rest of the team saw two Giant clams and a snake! 

Still magnificent at Terumbu Semakau

A small team divert to this shore at the last minute. This submerged reef lies right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom, and less than an hour away from the Central Business District.

Despite the drizzle and short working window in the dark, we find happy corals and many Magnificent anemones. The seagrass situation seems unchanged and we continue to hope for the best.

Terumbu Semakau still spectacular

This morning, a small team surveys this submerged reef right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom, and less than an hour away from the Central Business District.

The corals seem to be doing very well! The seagrass situation seems unchanged.

Terumbu Semakau still doing well

On a scorching morning, a small team surveys this submerged reef right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom (producing emissions that resembles clouds).

The corals are doing well, we see common reef life and the seagrass situation seems to be very slowly improving.

Terumbu Semakau alive and well

This submerged reef right next to Singapore's only landfill and near the petrochemical plants on Pulau Bukom is very much alive! Large clusters of Magnificent anemones are common here, looking a little deflated at low tide.

Our last survey at Terumbu Semakau was in Jul 2020, just after lockdown was lifted, and when we got the alert that signs of mass coral bleaching were noted during the lockdown. Today, I saw lots of healthy corals, interesting marine life and more signs of a return of seagrasses. 

Terumbu Semakau with mass coral bleaching

Dr Jani Tanzil alerted us that mass coral bleaching may have started on our shores since the second week of June. So we are on the look out for this as we check up on Terumbu Semakau.

Today, I estimate about 5% of the hard corals that I saw are bleaching, with an additional 20% showing stress (paler than usual or with bleaching portions) or with recently dead patches. I didn't see many leathery soft corals. About 5% of these were outright bleaching (white), while about 30% were more yellow than usual. This is not as bad as what I saw during mass coral bleaching here in 2016.

Terumbu Semakau still alive

There are reefs and seagrasses on Terumbu Semakau that lies next to the landfill and near Pulau Bukom.

I was worried to see a few corals that were bleaching, but most of the corals seemed alright. The seagrass situation seems to be slowly improving. The rest of the team saw lots of interesting animals including a seahorse!

Next to the landfill, amazing living reefs at Terumbu Semakau!

Right next to the Landfill, there are rich living reefs on Terumbu Semakau!

Teeming with corals, fishes and other special creatures. Today we saw seahorses, clown anemonefishes, giant clams, tiger cowrie and more!

Terumbu Semakau with large fish traps

We survey Terumbu Semakau at dawn and sadly find several large fish traps on the living reef edge.

But it was good to see healthy corals and marine life. Jonathan spotted a sea turtle, and we all saw dolphins on the way home!

Terumbu Semakau still alive

One of the nicest submerged reefs in Singapore, Terumbu Semakau seemed rather quiet today. We sense fewer live corals, and we still saw some corals with bleached portions.

Our last survey here was at the height of mass coral bleaching in Jul 2016. When we estimate about 50% of the hard corals and 50% of the leathery soft corals are bleaching, and about 20% of the corals have died recently.

But we still saw some interesting marine life including healthy giant clams, lots of lively fishes and more.

Mass coral bleaching at Terumbu Semakau

Mass coral bleaching is happening at Terumbu Semakau.

We estimate about 50% of the hard corals and 50% of the leathery soft corals are bleaching. We estimate 20% of the corals have died recently.

Terumbu Semakau: no coral bleaching

A gorgeous sunset over the city as we explored Terumbu Semakau, a submerged reef just off the Semakau Landfill.

I was relieved to see no signs of coral bleaching, but sad that the seagrasses have not returned to the Terumbu.

Checking up on Terumbu Semakau

Next to Singapore's only Landfill is a submerged reef called Terumbu Semakau. It has living reefs with fascinating marine life. Like this cluster of healthy Acropora corals.

We saw giant clams, seahorse, rare snails and an explosion of Magnificent anemones. But we couldn't find many anemonefish and there were still large fish traps on the shore.

Terumbu Semakau: still no seagrass recovery

Are corals at Terumbu Semakau bleaching? How are the seagrasses doing?

How delightful to see False clown anemonefish in the many colourful Magnificent anemones, lots of healthy corals. But sadly, signs of a massive fish trapping system, and no recovery in seagrasses.

Southern shores in the Draft Master Plan 2013

The main changes to the Southern Island in the Plan include plans to build create a freshwater reservoir next to Pulau Brani and a new waterfront park at Keppel Island.

The original natural part of Pulau Semakau is now marked green in the Parks and Waterbodies Plan 2013 overlay. Otherwise, there doesn't seem to be much changes in the status of the Southern Islands and Western Islands.

Terumbu Semakau on Day 5.5 of the Southern Expedition

We gather at 3.30am for our first official predawn trip of the Southern Expedition.

We had a great trip with lots of special finds as well as good representatives of our commonly encountered marine life.

Sharky Terumbu Semakau

Another predawn arrival on a submerged reef in high water! Knee-high water is perfect for sharks and rays which hunt smaller fish in the shallow water.

So we are careful as we land in the clear waters of Terumbu Semakau.

Dredging off Cyrene Reef and other Southern coastal works

There'll be dredging next to Cyrene until April. As well as dredging and other massive works next to Pulau Jong and Terumbu Semakau for works on the Shell pipeline for crude oil to Pulau Bukom.

Dredging next to Cyrene in Jul 2011.

Meanwhile, huge on-going reclamation continues: next to Labrador for the new Pasir Panjang Container Terminal continues, with more dredging; and at Tuas.