Living reefs at Terumbu Raya

Terumbu Raya at glorious sunrise, the tide is still high! Water as far as we can see, when we first landed.

I have not visited this submerged reef for a long time. My last trip to the reef was in May 10. Today, I hoped to check on how the reefs are doing after the coral bleaching event last year.

Terumbu Raya is a large submerged reef that lies very close to the natural shores of Pulau Semakau. Terumbu Raya has lots of interesting marine life and reefs packed with many interesting and rarely seen corals.
I decided to focus on the reef edge facing Pulau Semakau to see how the corals have survived coral bleaching. My last look at this portion of the reef was in Feb 09 so I didn't really see it during the bleaching event. More about coral bleaching on Bleach Watch Singapore.

Here's another view of the reef with Pulau Semakau on the horizon. The edge plunges away!

Here's a view of the reef with Pulau Bukom and a bit of Pulau Hantu on the horizon. As the tide wasn't super low, I got very wet getting close to the corals here.

Today I spent all the time in deep water trying to photograph the reef with sneaky swimming camera. It was tricky as the water wasn't very clear. Packed together were hard corals, anemones, sponges and lots of fishes that swam away quickly.

Some parts are teeming with different kinds of corals in all kinds of shapes and colours.

There are lots of delicate plate forming corals.

With many large coral colonies!

A lovely pink Anemone coral with an orange fanworm in it.

More fanworms 'bloom' in this colony of Lettuce coral (Pavona sp.).

Terumbu Raya is a great place to see some corals that are not so commonly seen. Such as the elegant Moon corals (Diploastrea heliopora).

There were several large well-formed plate corals that I think are Bracket fungi corals. I don't often see these corals on other shores.

It was nice to come across a Euphyllid corals (Family Euphyllidae), albeit a small one. These corals were badly affected by coral bleaching.

I saw one Ringed plate coral (Pachyseris sp.). So far, I usually see these corals growing in deeper waters near the reef edge.

I saw many beautiful Ridged plate coral (Merulina sp.), forming cups or encrusting the rocks.

There are many Carnation coral (Pectinia sp.) in pretty colours.

I saw one Acropora coral (Acropora sp.) that seemed unbleached.

There are lots of Pebble coral (Astreopora sp.) here. Some have white portions, or are in odd colours of pink and bright green. Most were brown.

Here are some corals that I'm not sure of. Perhaps they are some kind of plate forming Montipora corals (Montipora sp.)?

I saw two small Mole mushroom corals (Polyphyllia sp.). One seemed to be bleached.

Lots of boulder shaped corals in different sizes and colours dotted the reef.

As usual, the most common hard coral on the shore were Favid corals (Family Faviidae).

Here's more Favid corals that I saw. Some were rather pale, but many seemed to be in their usual colours.

I also saw many small colonies of Galaxy coral (Galaxea sp.). All those I saw were not bleached.

There are many Anemone corals (Goniopora sp.) here. Some still showed pale or white portions.

I saw many Brain corals (Family Mussidae), most seemed to be unbleached.

I only saw Cauliflower corals (Pocillopora sp.) in the shallower areas. The few I saw were not bleached.

I saw one Flowery disk coral (Turbinaria sp.) and many Ruffled disk corals (Turbinaria sp.).

There are also many large anemones in this part of the reef.

The most abundant anemone I saw on the reef were Bubble tip anemones (Entacmea quadricolor). Many of them showed signs of bleaching. Even more disturbingly, I didn't see a single Tomato anemonefish (Amphiprion frenatus) in any of them.

Here's a selection of the many Bubble tip anemones that I saw today.

I saw one Pizza anemone (Cryptodendrum adhaesivum).

There were a few Giant sea anemones (Stichodactyla gigantea) and most had only a few very very tiny Clown anemonefish (Amphiprion ocellaris).

Here's an intriguing anemone that I saw. It was much shorter fatter tentacles than the Giant anemone, and a pale body column with bright purple-pink bumps. Could it be Merten's anemone (Stichodactyla mertensii)? There was a small anemonefish in it too.

Terumbu Raya is one place where we have found many Fire anemones (Actinodendron sp.). So it was not surprising to see one in the sandy area just before we left.

There was a small patch of Zoanthids or colonial anemones (Order Zoanthidea) that were very white.

Several large sponges are also seen here. Including several Barrel sponges (Xestospongia testudinaria).

Other sponges include these yellow prickly sponges (Pseudoceratina purpurea). These sponges contain powerful anti-cancer compounds.

We saw a small Red feather star (Class Crinoidea)!

Wow, a Black long-spined sea urchin (Diadema sp.) that I accidentally photographed!

Russel spotted a Burrowing snake eel (Pisodonophis crancrivorous) soon after we landed, while the water was still high. It was quite unafraid of us and allowed us to get quite close to photograph it!

I also accidentally photographed some of the small fishes that were swimming around in the area!

Tang Ling and Wee Hock saw a Tiger-tailed seahorse (Hippocampus comes)! Alas, today Alex and crew did not see any sea turtles or dolphins while waiting for us on the boat.

Brandon shared this awesome video clip of the marine life on Terumbu Raya!


We are glad, however, not to have come across any abandoned nets or fish traps. Although we didn't manage to survey the entire Terumbu.

Thankfully we had another day of clear weather, and a cool cloudy day too. Thanks also to Tang Ling and Wee Hock for contributing to the boat fare!

Tomorrow, it's back early in the morning to Cyrene for TeamSeagrass monitoring!

Other posts about this trip

• Russel on facebook with lovely photos of corals and of the burrowing snake-eel!