S's of Cyrene Reef: Slugs, stars and sharks!

Two weeks ago, we went to Cyrene Reef on a predawn trip and set off from Marina @ Keppel Bay way before sunrise. I was quite excited on this trip because I have not visited this awesome shore since September last year.

This is the sight of the landscape when we arrived near Cyrene Reef. Cyrene is a submerged reef that will only be exposed during low spring tide. At night time, the only prominent visible feature is the lighting of Pulau Bukom where the oil refinery is situated.

As there is no jetty at Cyrene Reef, we need to land amphibiously by transfering to the dinghy. This requires quite a bit of effort and skills and we are thankful to Alex and his crew. From the small boat, I took this photo showing our operation at night.

The trip proved to be fruitful with lots of S's! Slugs are among my favourite marine critters. I usually spot super tiny sea slugs such as this Aeolid nudibranch (probably Cratena sp.) accidentally when I squat down to look at something else.

Stephen's wish for the trip is to find the Blue dragon nudibranch (Pteraeolidia ianthina). And I was glad to fulfill it by finding one among the sand and seagrass.

This is a super tiny slug of less than 1cm in size which I have never seen before. Chay Hoon suggested that this is Flabellina bicolor.

Larger than sea slugs, this Extraordinary sea hare (Aplysia extraordinaria) is another type of gastropods known as sea hare.

Compared to my previous trip last year, I did not come across many China moon snails (Natica onca). My only sighting was quite interesting though. The moon snail was feeding on a clam of about its same size!

Sponges can look harmless from far but this 'Hairy olives' sponge (Stelletta clavosa) is one of those with a framework of spicules (tiny, hard spikes) throughout their body. These spicules are sharp and needle-like so I'm sure you do not want to handle these "softies".

Another organisms with pointy projections will be the Lovenia heart urchin (Lovenia elongata)! The heart urchin has spines that allows for movement.

We have been coming across Swimming anemones (Boloceroides mcmurrichi) with beige tentacles and white stripes. Are these anemones something else all together?

These two tiny crabs are quite pretty! I have not seen them before though and have no idea what they are.

Marcus found a special mantis shrimp! The huge front pincers of this Banded mantis shrimp (Lysiosquilla sp.) resemble those of the Praying mantis insect or the blade of a pocket knife that folds into the handle. Armed with sharp spines, the pincers extend and retract very quickly and the sharp spines impale soft, fast-moving prey like fish and prawns.

This moon snail with white coloration on some parts of the shell resembles the Eggwhite moon snail (Polinices albumen). We are thinking that this could be a juvenile.

The Thorny sea cucumber (Colochirus quadrangularis) is very commonly found on our northern shores but seldom seen in the south.

Marcus found a juvenile version of the rare Brown sea cucumber (Bohadschia vitiensis)! This sea cucumber has only been recorded intertidally from Cyrene Reef and Semakau.

Without saying, there are lots of Knobbly sea stars (Protoreaster nodosus) on Cyrene. This is the second "S" of Cyrene Reef. My focus in this blog post will be on the juvenile knobblies which show that the population on Cyrene is sustainable with new stars still being formed.

Russel found this knobbly sea star snacking on a sea urchin! This is my first time seeing such a feeding behaviour.

I was more than happy and satisfied to see four Pentaceraster sea stars (Pentaceraster mammilatus)! Though this sea star has been sighted at Semakau before, they are more commonly found at Cyrene and no where else.

However, the identity of sea stars may not be that clear cut, especially for the sea star on the right side of the photo. It looks like a combination or hybrid of a knobbly and a pentaceraster.

After the sunrise and the heat kicking it, the huge knobblies start to get "half-baked". They would fold them arms to reduce surface area to the air so as to minimise loss of water.

It's amazing how rich marine life can be found right in front of Pasir Panjang Ferry Terminal with huge containers passing by the waters surrounding Cyrene.

In addition, the shore is also ringed by Pulau Bukom and Jurong Island.

The last "S" of the trip will be the numerous shark encounters! This is a photo taken by Russel. I personally witnessed two swimming in front of me swiftly and the encounters were too fast for me to take a snapshot. Nevertheless, it was exhilarating to spot these majestic creatures.