Tuesday, April 27, 2010

Pulau Tioman with Canadian International School Singapore

When I told my brother that I was going to Pulau Tioman for 8 days, his response was, "Are there that many things to see on the island?"

But of course, I was not there for a sight-seeing or leisure trip. We were conducting a field study camp for Canadian International School Singapore!

While we will be staying on the island for 8 days (17-24 April 2010), the students would only spend 4 days on the island. That's because we were running 2 camps consecutively for 2 different batches of students. There were about 40 students per batch.

We met around 5 plus in the morning at the school, and took a chartered bus to Tanjung Gemok to be transferred to a ferry to Pulau Tioman.

We were rather lucky that the ferry left on time, and we reached the island around 1 plus in the afternoon. After lunch, we had our first activity - an orientation walk around Paya Beach Resort. This walk also introduced some of the coastal and mangrove vegetation to the students.

Many coastal plants have thick leaves to retain water, since the coastal environment is very dry due to the sea and land breeze which increase the rate of evaporation. This is a hoya plant (Hoya sp.), and even its flowers have thick petals! The leaves often have very smooth surfaces to ensure that any salt from salt sprays will be easily swept away by the wind.

Near the hoya was a stingless bee (Tribe Meliponini) hive. These bees have highly reduced stings that cannot be used for defense.

We spotted this centipede (Class Chilopoda) on a sea apple tree (Syzygium grandis) for the first batch of students. It was feeding on a caterpillar!

There was also this poor bee that was attacked by red weaver ants (Oecophylla smaragdina). These ants are very aggressive and give painful bites.

Apart from the organisms above, the students also saw other plants like the casuarina, cashew, lemon grass, mistletoe, nipah palm, sea lettuce, sea morning glory, bakau, etc. Other animals we saw include many different types of butterflies, grasshoppers, fiddler crabs, mudskippers, spiders, etc.

On the second day, the students started off with an intertidal walk in the morning. Paya Beach Resort has a very nice intertidal area with huge colonies of corals.

While we did not see the cryptic rock stars (Cryptasterina sp.) for the first batch of students, we saw quite a few of them for the second batch! These sea stars were quite small, and camouflaged very well with the surrounding rocks.

We also found a few juvenile cushion stars (Culcita novaeguineae). This was a rather special one with 6 arms!

We also found a mature cushion star, and it certainly looked quite different from the juveniles, appearing more like a huge cushion. These sea stars feed on corals.

There were lots of sea cucumbers here, and this was just one of them - a lollyfish [Holothuria (Halodeima) atra]. They feed on tiny organic matter on the sand, picking them up with oral tentacles.

One of the groups found this cluster of eggs under a rock! They looked like octopus eggs to me. For the first batch of students, we saw a few octopuses too, but unfortunately I forgot to take photos.

One of the groups found this pretty file clam (Limaria sp.) under a rock. It had lots of tentacles, which could break upon contact with predators to distract the latter. It could swim by flapping its two halves of its shell too.

There were a few cone snails (Family Conidae) too. These snails are venomous, and one should never handle them with bare hands. Some cone snails stings can even be fatal!

There was also a spider conch (Lambis lambis), which got its name from the many spines extending from its shell.

Other organisms we saw include lots of seaweeds, a few seagrasses, brittle stars, nudibranchs, sap-sucking slugs, various types of crabs, shrimps, cowries, giant clams, oysters, etc.

In the afternoon, we did a stream study to check out the organisms living inside. We saw many freshwater crabs, shrimps, snails and insect larvae. Did not take many photos except the two below though.

This is probably a dragonfly larva. They feed on other small animals in the stream.

This should be a Bucccinid snail (Family Buccinidae). It had a long proboscis for sniffing out its food. Not sure what it feeds on though.

Interestingly, we found a dog-faced water snake (Cerberus rynchops) here! This snake can be commonly found in the mangrove, but this was the first time I saw it in a freshwater stream, quite a distance from the mangrove! Could it have swam upstream from the river mouth?

We saw more of these snakes during our night walk on the same evening, when we walk into the mangroves.

But the main attraction of the mangrove, at least for me, was this mud lobster (Thalassina anomala). This animals is hardly seen above ground, as it spends most of its time in its burrow. Mud lobsters are very important in the mangrove ecosystem, as they feed on organic matter in the mud, and as they feed and dig, they bring fresh mud nutrients to the surface, forming huge mounds. Many plants (ferns, coastal plants etc) and animals (crabs, insects, snakes etc) grow/live on mud lobster mounds, due to the availability of nutrients, and the tall mounds allow these organisms to stay out of the reach of sea water.

During the night walk, we also ventured into the secondary forest, and saw a few night animals like this terrestrial flatworm.

The highlight of the walk in the forest would be the numerous Horsfield's flying squirrels (Iomys horsfieldi) we saw high up on the sea apple trees. And they were feeding on the sea apples! These small mammals have a flap of skin on each side of its body, between the front and back legs. They can glide from tree to tree by spreading their limbs as they jump, hence extending the flap like a kite.

We also saw many bats, a few fireflies and several huge spiders.

On the third day of the camp, we went snorkeling!

The first snorkelling site we went was Renggis Island. It's a natural reef with lots and lots of hard corals!

There were lots of fishes too! The above were mostly sergeant damselfishes (Abudefduf spp.)

There were many black long-spined sea urchins (Diadema setosum). These animals have venomous spines which give painful stings.

Another animal with venomous spines was this crown-of-thorns sea star (Acanthaster planci). This sea star feeds on corals.

There were many huge sea anemones here too. The above are magnificent sea anemones (Heteractis magnifica). Can you find the clownfish among the tentacles?

Here's a closer look at the clownfish - an ocellaris clownfish (Amphiprion ocellaris). The clownfish has a layer of mucus on its body, preventing it from being stung by the sea anemone. It is protected from predators among the stinging tentacles, and in return, it chases away fishes that feed on the tentacles of the anemone.

We spotted a few stinging hydroids, but fortunately, not one was stung by them. They appeared like little, feathery trees, but could give painful stings when contact.

There were lots of giant clams (Tridacna spp.) too. The above should be a fluted giant clam (Tridacna squamosa).

The next stop was an artificial reef.

There were lots of man-made concrete structures on the seabed, but very few corals were growing on them.

There were lots of fishes though, and the students thoroughly enjoyed snorkeling among them.

We saw many silver moonies (Monodactylus argenteus).

These are orange-spotted rabbitfish (Siganus guttatus). They have venomous spines that can give painful stings.

Closely related are these double-barred rabbitfish (Siganus virgatus).

The trevallies (Family Carangidae) were a common sight here, and we saw huge schools of them.

So were the scissortail sergeanst (Abudefduf sexfasciatus).

The most colourful fish we saw must be the parrotfish (Family Scaridae). They possess parrot-like beaks which allow them to rasp algae from corals and rocks.

Interestingly, I found this anemonefish, which I thought looked like a black variety of Clark's clownfish (Amphiprion clarkii), swimming up and down the water column. A closer look revealed that it was picking up crumbs of bread thrown down by tourists, and bringing them back to its host sea anemone! Studies have shown that anemonefish feeds its host anemone with food that they found, but never did I expect to see it happening with my own eyes in the wild!

Soon, it was time to go. I was rather happy that I managed to get a photo which captured both the above and under water scene! :P

In the afternoon, the students were given a group project, and finally we instructors got to rest for a while. It drizzled a little during the project discussion for the first batch, and we were greeted by a beautiful rainbow when we went to the restaurant for dinner!

On the whole, it was a great trip, with 2 batches of very lively students! Hope the students enjoyed the field study camp as much as we do! :)

More photos of the trip at:


Chris said...

Great photos as usual. Just one comment. The tridacna clam photoed above is t.maxima not t.squamosa.

koksheng said...

I like the part where the clownfish feeding the anemone! Very cool, though a bit not natural since bread is not their diet. Haha.

Lovely six arm juvenile cushion too!

tHE tiDE cHAsER said...

Hi Chris, I still think it should be a squamosa actually, since the scutes are way too protruding. There are variations, and so the only sure way to tell between the two is to look at the hinge, at least that's what my malacologist friend told me.

Hi KS, yah, not too natural, but at least they are doing it in the wild, not in a tank. They will probably scavenge for other food particles in a natural setting too.