07 July 2024

Mass coral bleaching and oil spill impact at East Coast coral garden and seagrass meadows

Heartbreak as we survey the reef that has settled at a seawall on the other side of Tanah Merah Ferry Terminal next to the East Coast PCN. We estimate 90% of the corals here are bleaching or highly stressed, and about 50% already have dying/dead portions. 
Mass coral bleaching 2024 check at East Coast Park (PCN), 7 Jul 2024
One of our nicest seagrass patches is growing at the mouth of a canal here and fortunately, they seem alright for now. Oil is still very present on this shore which is not cleaned as it is not a recreational beach. We also had a quick look at the shore opposite NSRCC, which is being cleaned.

As usual, the rest of the team find lots of marine life in the seagrasses and coral reefs at this East Coast Park canal where the oil is not cleaned as it is not a recreational beach. On the artificial seawall, there are still the usual large crabs, large cowries and common snails - some laying eggs on the rock. On the sandy areas there were live burrowing animals like snapping shrimps, sea anemones, clams, sand dollars, sea cucumbers. Among the seagrasses there were hermit crabs and small fishes of various kinds. The soft ground made it hard to get to the reef edge beyond the montipora patch but the team managed a shot in the dark of the mass coral bleaching going there.
Collage of photos by the team.
Links to their albums below.
Our shores are currently being impacted by mass coral bleaching. So it was not surprising to see this happening on the corals that have settled naturally on this artificial shore. I do not know how to distinguish whether bleaching is due to the stress of higher water temperature or impact of the 400tonne Pasir Panjang oil spill on 14 Jun 2024. The huge patch of Branching montipora corals (about 5m x 5m) is bleaching. Seems that mostly only the tips are dead, hopefully it can recover soon.
Most of the boulder shaped corals were bleaching white, or had dying tissues (bluish grey that smells very bad) or dead portions. Many of the plate forming corals were also pale or bleaching white with dying tissues in the middle of the 'cup-shaped' form - perhaps because oil tends to pool here? But we did see a few colonies that were alright. 
I looked at corals that in the past bleached first: Cauliflower corals (I saw only two, both were bleached), Sandpaper corals. There was a small cluster of Anemone corals it was bleaching. A few corals were alright. The situation is very different from what we saw on our last survey on Aug 2023.
Other cnidarians can also bleach. I saw three Giant carpet anemones, two with Clown anemonefishes. Two were pale and stressed, one (top photo) was outright bleaching and seemed to be dying as it was no longer attached to a hard surface. If this anemone dies, the fish will probably also die as it is highly unlikely to survive without its anemone home.
One of the nicest patch of seagrasses in Singapore is at the mouth of this canal. Almost all the seagrass species for Singapore can be found here. As in the past and 2 weeks ago, today, the seagrasses were lush and healthy, green and fresh without much epiphytes, leaves long and not cropped. I didn't see any bleaching seagrasses and there was no sign of oil at the mouth of the canal. There were still Tape seagrass with long leaves. Nasry spotted a Tape seagrass fruit that had just released the seeds! 
Stuff washed up on the shore often suggest damage going on in deeper water. There was broken off bits of all kinds of seagrasses, some broken at the base of the leaves. Nasry pointed out a pile of dead Jania red seaweeds. And I saw sections of 'bleached' Halimeda seaweed as I did 2 weeks ago here. I also saw a patch of red 'furry' stuff growing on seaweeds, may be cyanobacteria.
Inside the canal, there are still small slicks of oil along the water line. Footprints higher up in the canal had black oil (suggesting oil has seeped into the sand here), but at the mouth of the canal, footprints were clear. Smell alerted me to spots of oil on the seawall, some on the northern side of the canal, and another near the field of Branching montipora on the southern side of the bay. After crossing the canal, I saw the lower branches of shrub on the high shore heavily covered in oil, it was clearly dipped into some floating oil at high tide. 
The stain along the southern wall of the canal is still there. Seems to be two bands in some areas. There are still lots of live animals! On the heavily stained portion there were surprisingly large crabs. The smaller crabs were seen outside the stain. Maybe they are eating the oysters - white inner shell suggest upper shell was pried open after the stain? There were also lots of little Periwinkle snails on the stained area and above. There were even limpets with oil on their shells which clearly had been eating their surroundings, clear of oil! There were also small Jeweled chitons and Onch slugs. My high res photos of the survey of the PCN shores on wildsingapore flickr.
Just in front of NSRCC East Coast, there are living sandy shores and lush seagrasses in front of the canal there. These have all taken root naturally, without any human planting. We had a quick look before the tide turned. The boom across the canal is still there, with some signs on of oil on the sand. I couldn't see oil stains on the canal walls though. There were small pancakes and clumps of oil on the shoreline, with a slick of oil on the water's edge. There was some smell of oil, but it was not overpowering. The seawall don't appear to be badly oiled.
Although there is oil sheen in the water, the remains dense growths of seagrasses on the shore. But I didn't come across any animals in the seagrass, unlike our last survey in Aug 2023.
Although the sandy shores here appear bare, a careful look at signs on the sand surface suggest the life beneath. Compared to our last survey in Aug 2023, I saw fewer animals. But there were still many coils of 'processed sand' created by buried Acorn worms. Also some small to tiny Cake sand dollars, small patches of living Button snails which leave typical dots on the sand surface. I saw a few Weasel olive snails, some Moon snails and their Sand collar egg mass. There was one Bonnet snail, unfortunately oiled at the top of its shell. Richard spotted a tiny Knobbly sea star, and I saw a cerianthid. There were many burrows of crabs small to large on the higher shore. My high res photos of the survey of the NSRCC shores on wildsingapore flickr.
We will continue to check up on these shores.

Where did corals at East Coast Park come from?

The babies of these corals are from Singapore reefs! This chart shared in the Long-Term Plan Review shows coral larvae (babies) dispersal in our waters from mass coral spawning. This highlights the importance of protecting our 'mother reefs' so that they can continue to produce babies that settle all along our shoreline.
The same currents that brought the oil spill to East Coast Park from Pasir Panjang also bring coral babies to this shore!
Map by Channel NewsAsia 19 Jun 2024.

What is the fate of these shores?

These shores lie west of Tanah Merah Ferry Terminal and are slated for massive reclamation outlined recently in the Long-Term Plan Review.
Technical studies for 'Long Island' 800ha reclamation off the East Coast were recently announced to begin.
Natural regeneration on Singapore's artificial shores and structures is already happening now. Unintentionally, with zero replanting. Can we plan coastal works to allow reefs, mangroves and seagrasses to naturally regenerate? Naturalise canals leading to the sea for a continuum of freshwater wetlands to mangroves? Imagine what's possible! Reefs and natural marine ecosystems at our doorstep, for all in the City to enjoy. More about this idea in my feedback to the Draft Master Plan 2013.

The Singapore Blue Plan 2018

Check out the Sinapore Blue Plan 2018 which outlines community recommendations for all these shores. DOWNLOAD the Plan, SUPPORT the Plan! More on the Singapore Blue Plan 2018 site.

See these and other East Coast shores for yourself!

It's fun and easy to explore these shores. After the shores are reopened when oil spill cleanup is completed, you can explore them for yourself. More details in East Coast Park - Surprising intertidal adventures for the family.

Photos by others on this survey

Richard Kuah

Rachael Goh

Muhd Nasry

Tommy Tan


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