Saturday, February 14, 2009

OJT1 at Changi Beach Park 090209

Had my first on job training (Mindy's second) on Monday, 9th Feb. The guides who went down that day were Luan Keng, Ron, Siyang, Robert and Kok Sheng. As we were early, we had some time to ourselves before the girls from MGS arrived. As it turned out, we had our first 'sighting' soon after sitting down...

...a very cute and tiny orangey-brown ladybug! It is known as Harmonia sedecimnotata (thanks Anonymous!).

Soon after, Robert headed to us carrying two tests (internal skeletons) of sea urchins. Above is the underside of a test of a White Sea Urchin (Salmacis sp.). There's a pic of a live White Sea Urchin below.

Different species of sea urchins have tests of different size and colour. On the right is the test of a Black Sea Urchin (Temnopleurus toreumaticus).
Always remember to put back the organisms - dead or alive - where you found them!
Soon, the girls from MGS arrived and each guide went to meet their group. I was attached to KS's group while Mindy went to join Robert's. At the supralittoral zone, the girls had their first 'discovery', which was none other than the small balls of sand that dotted the beach in clusters...
...made by what else, but the Sand Bubbler Crab (Scopimera sp.). The best way to see this crab is to keep still and not make any sudden movements. It will come out of its burrow soon enough.

In this photo: Robert's group. Mindy is hidden behind.
Many of the girls were fascinated by the colourful 'kites' flying in the distance, which belonged to the people who were out kitesurfing. Seems real cool!

This Razor Clam (Family Solenidae) aka Bamboo Clam caused quite a lot of excitement. We got to see it 'live' in action and quite a show it was too! The clam shocked everyone by 'torpedo-ing' itself forward, using water sucked in and out of its siphon (look at the part of the clam at the far left of the pic, the other end is its foot) to do so. It moved so fast that I had no time to get a video of it in action. It even squirted a stream of water at one girl, causing her to squeal.

There was a sea cucumber (classification unknown) nearby too, and the razor clam torpedoed itself over. Lol.

It soon settled down at one spot and used it muscular foot to burrow quickly into the wet sand, leaving its siphon sticking out so that it could breathe and feed.

Another shot of the unknown sea cucumber.

Growing on some debris (I think) was this sponge (the protruding branching knob-like structures).

Camouflaged against the substrate was this Plain Sand Star (Astropecten sp.).

Remember the test of the White Sea Urchin earlier? Well, this is how that species of sea urchin looks like when it is alive.

What I mistook for a Thorny Sea Cucumber (Colochirus quadrangularis) was actually a Warty Sea Cucumber (Cercodemas anceps). It's easy to get confused between the two as both are colourful, and largely pink, at that.

Have been wanting to see a Noble Volute (Cymbiola nobilis) for quite some time and I finally got my chance to that day! These amazing creatures have a magnificent shell that has markings which resemble mountain ranges. If I'm not wrong, each shell has their own unique markings, so two shells are never the same.

Their muscular body is spotted with orange dots of varying sizes, making them even more outstanding. Sadly, these creatures are fast dwindling in numbers in Singapore due to over-collection for their beautiful shell and over-hunting (even though they're edible, it doesn't mean that one has to eat them).

There were a lot of Cake Sand Dollars (Arachnoides placenta) on the beach that day. This is the underside of one. To the undiscerning visitor, they are difficult to spot as they look like raised circular lumps of sand (they usually burrow into the sand).

As the original pic isn't very clear, I took the liberty of enhancing it.

The topside of the another Cake Sand Dollar.

The underside of it. Wonder why it differs so much from that of the first sand dollar? Might that have been a juvenile?

Enhanced image.

First noticed this in the sand when one of the girls asked me what it was.

Well, it turned out to be a Ball Sea Cucumber (Phyllophorus spiculata) that was largely buried in the sand. Their body fluids have medicinal properties.

Just a short distance behind KS, I spotted this very unusual and pretty snail moving across the sand. I couldn't help but go over to take a better look. It reminds me of a strawberry somehow. Haha. It's actually a helmet shell (scientific name: Semicassis bisulcatum). KS gave me a questioning look when he realised I had slipped away from the group to get a better look at this snail. Oops.

Wandering about with its long siphon out.

I had many 'firsts' during this trip, including my first encounter with a sea hare! This is a Hairy Sea Hare (Bursatella leachii). When in season, these creatures can come in the thousands.

A dead Horseshoe Crab.

Yup, another 'first' for me! During the guided walk, we encountered a couple of Spotted Moon Crabs (Ashtoret lunaris). All of their legs are paddle-shaped as they are burrowers.

Humans rarely appear in this blog, but I thought it'd have a change for this entry. That's Mindy on the left, and me on the right. Thanks to SY who took this photo :)

For this entry, I referred frequently to Wild Fact Sheets of marine life on Singapore shores (, as well as KS ( and Ron's ( related blog entries.

Upon joining KS's group, I suddenly felt a bit apprehensive but that soon passed as the guided walk progressed. KS even gave me a chance to do some impromptu guiding. Haha. It was great to see the girls getting excited over their discoveries during the course of the walk. Overall, it was a good experience! And if anything, the more I know, the less I seem to. The only way to combat that, I feel, is to know as much as I can by exploring, observing and reading. Will work on improving my photography skills too!


  1. Hi, nice pic of the ladybird you got there. But anyway, that is no Epilachna indica. That is Harmonia sedecimnotata.

  2. Hi. Thanks for pointing it out! Realised that Epilachna indica has 5 spots on each side whereas Harmonia sedecimnotata has 8. Are you working on ladybugs by any chance?

  3. yeah, epilachna indica has 6 spots (standard but u will find some variations)on each side of the elytra... yeah, but im just a ladybug amateur.. been studying them for almost 3 years now...