Thursday, January 29, 2009

Sungei Buloh on 29 Jan 2009

Today I was back at Sungei Buloh for another guided walk. The students were late and thus I didn't really have much spare time to take photos. But fortunately, we still managed to cover most of the interesting aspects of the reserve, with in fact quite a few nice surprises too!

Berembang (Sonneratia caseolaris)
The berembang (Sonneratia caseolaris) was blooming! Previously, it was believed that this plant only flowers at night, but recent researches have shown that it blooms both at night and during the day, and of course, now I am seeing it with my own eyes. It was also observed that more pollinators, in terms of both diversity and frequency, visit the flower during the day, probably due to the higher volume and energy value of nectar in the morning.

Tiger moth
We spotted this very pretty tiger moth (Family Arctiidae) resting on the main bridge just before the students arrived. Most species of tiger moths tend to be more active during the day rather than at night.

Malayan water monitor lizard (Varanus salvator)
As we reached the freshwater pond, there was this huge Malayan water monitor lizard (Varanus salvator) slowly crawling underneath the boardwalk, and the students were really excited about seeing this huge animal so up close!

Brownlowia tersa
And course, Sungei buloh has a rich variety of mangrove plants. Today, I decided to take a photo of this Brownlowia tersa. This mangrove plant is quite rare on the whole, but in Sungei Buloh there are quite a few patches. Locals used to use this plant for fencing or as firewood.

Giant mudskipper (Periophthalmodon schlosseri)
The giant mudskipper (Periophthalmodon schlosseri) is the biggest mudskipper in Singapore. As the tide is rather high, the mudskipper looked very clean and free of mud compared with the ones we saw during our last trip here.

Tree-climbing crabs (Episesarma sp.)
And also because of the high tide, we saw lots of tree-climbing crabs (Episesarma spp.) on the trees, getting away from the predatory fishes that came in with the rising tide! These crabs are able to climb up trees with their pointed legs.

Smooth otter (Lutrogale perspicillata)
The highlight of the day must be this smooth otter (Lutrogale perspicillata)! The earlier group actually saw 3 of them playing in the freshwater pond. Another group saw 2 of them just underneath the boardwalk! I didn't managed to get a good photo as it was moving really fast.

And here's a short video clip of the otter.

And at the main hide, there were lots of migratory birds in the pond. Certainly a great way to end the day's exploration!

Wednesday, January 28, 2009

Sentosa on 27 Jan 2009

It's been a while since I last visit the shores of Sentosa, and so on Lunar New Year Day 2, LK, ST and I decided to visit this little island. Tide wasn't really very low, and so I didn't really expect to see many things. But guess I was wrong :)

Sentosa cliff
One of the things that kept drawing me back to Sentosa are the beautiful coastal landforms - spectacular cliffs, pretty arches, mysterious caves... You can find all of these at the rocky shore.

Rocky shore
Signs of erosion at the shore, where the softer rocks were eroded and swept away by the waves, and the remaining harder rocks forming parallel ridges.

The last time I was here, there was a landslide on this slope. Some kind of reinforcement concrete has been built since then to ensure the slope will not slide down again.

Sand-sifting sea star (Archaster typicus)
On the sandy shore, I found a little sand-sifting sea star (Archaster typicus). This is a rather common sea star, and we have seen it on many of our southern islands, sometimes in the hundreds.

Carpet anemones (Stichodactyla haddoni)
There were several huge carpet anemones (Stichodactyla haddoni). These are animals with lots of sticky tentacles to capture their prey, such as little fishes or crabs.

Sponges were a common sight here too. These are also animals, and they feed by filtering for tiny food particles in the water sucked in through little pores on their body. The sponge above is Pseudoceratina purpurea.

Some sponges may look like seaweeds or even hard corals, like the Lamellodysidea herbacea sponge above. You can tell them apart from the pores and that they usually do not have a hard skeleton.

Montipora branching coral
And here are the real corals - the branching Montipora hard corals, growing among colonies of green ascidians.

Turbinaria coral
Hard corals come in various growth form, and some may look like somewhat plate-like or flower-like, like the Turbinaria coral above.

Porites coral
Others, like the Porites coral, may look like a rock.

Coral poylps
But if you look closer, you will realised that they all have little holes on them, and that's where all the coral animals, called polyps, live. The coral is basically like a HDB flat with lots of little occupants! Sometimes, corals may also fluoresce. This is due to their colour pigment, which supposedly helps prevent them from getting dun-burned.

Boomerang mushroom coral (Herpolitha limax)
While most corals are attached to the substrate, there are some, like the boomerang mushroom coral (Herpolitha limax), which are free-living.

Lobophyton soft coral
Not all corals are hard - we have soft corals too! Sentosa is also a good place to find huge colonies of soft corals. The above is a Lobophyton sp.

Tape seagrass (Enhalus acoroides)
While the corals are often mistaken for plants, here are the real plants - tape seagrass (Enhalus acoroides). Note that I'm refering to the long ribbon-like ones, not the hairy ones. Those are Bryopsis green algae.

Halymenia red algae
It appears that there is a Bryopsis algal bloom, and we can see them every where. But among the green patches, there were a few red patches of red Halymenia algae too. Kind of an auspicious colour for the Lunar New Year :P

Giant reef worm (Eunice aphroditois)
This giant reef worm (Eunice aphroditois) gave me a surprise when it suddenly appeared next to my feet. And of course, I immediately turned my camera towards it. Unfortunately, its head was hidden under the algae though.

Nudibranch (Dendrodoris denisoni)
Other interesting animals I spotted and remembered to take a photo include this little dendrodoris nudibranch (Dendrodoris denisoni). It was sliding over the sandy substrate when I spotted it.

Funeral nudibranch (Jorunna funebris)
There were quite a few funeral nudibranchs (Jorunna funebris) among the seaweed too.

Giant top shell (Trochus niloticus)
At the rocky area, I found this giant top shell (Trochus niloticus). This huge snail feeds on algae.

All too soon, the tide was rising and we had to leave the intertidal area. On the whole, it was quite a relief to find the intertidal area still doing fairly well despite the development work been carried out in the surrounding areas. Will probably visit this shore again during a lower tide.

Saturday, January 24, 2009

Woodlands Mangrove

At a little corner of Woodlands, there is this little patch of mangrove seldom visited by nature lovers. Today, however, I decided to pay it a visit on my own. My main objective was to find the wild berembang trees (Sonneratia caseolaris), a rare mangrove plant in Singapore. According to the "A Guide to Mangroves of Singapore", a few of these trees can be found here. This tree can be commonly found in the other countries in the region though.

I started at the back mangrove, which like most other back mangroves in Singapore, comprised mainly of the sea hibiscus (Talipariti tiliaceum).

Some of the sea hibiscus were fruiting, which attracted the cotton stainer bugs (Dysdercus decussatus) that feed on the seeds.

A stream ran through the mangrove, and I spotted several damselflies (Pseudagrion microcephalum) nearby.

I saw quite a few of moths too. Not sure of the ID though.

This common mangrove climber, Caesalpinia crista, was rather abundant here, climbing over the sea hibiscus trees.

And finally, I reached the true mangrove area. It was a fairly small, but charming patch. The stream was in a jade-like green, and most part of the ground was covered with a layer of moss and algae. I didn't venture too deep into the forest though, since I was alone and wasn't wearing booties. Kind of chicken out. Haha :)

Still, I managed to find several common mangrove species.

The dominating true mangrove tree appeared to be the api-api putih (Avicennia alba) shown above, and there were quite a number of very mature trees. There were a few api-api ludat (Avicennia officinalis) as well.

Bakau putih (Bruguiera cylindrica) was also quite common, and a few trees were flowering and fruiting.

A little higher up on the shore, a few blind-your-eyes (Excoecaria agallocha) can be found. The sap of this plant can cause blindness.

Both species of mangrove ferns, Acrostichum aureum (see above) and A. speciosum, were also found here.

After a short exploration, I suddenly see some cone-shaped pneumatophores sticking out of the ground. It's a Sonneratia! But was it what I was looking for? The tree was huge - the trunk was about 1 metre wide, and the tree was so tall that I could hardly see the leaves clearly. It has a very ancient feel to it though, being so huge and tall. I wondered how old it was. Somehow it felt rather magical when I was standing under this old tree.

After searching around the tree, I found some small branches with a few leaves near the base of the tree. From the shape of the leaves, it seemed to me that this is indeed a berembang (Sonneratia caseolaris)!

Below the tree, I also managed to find a few fruits. I looked around to see if I can find more of these trees.

But unfortunately, the only one nearby with cone-shaped pneumatophores was this dead tree. Since I didn't have my booties and couldn't explore too far, I decided to walk along the edge of the mangrove forest to see if I can spot any berembang leaves among the canopy. It appeared that there were at least 2 other Sonneratia trees, but since I couldn't venture into the softer areas without my booties, I couldn't check out the species.

On my way out, I saw this cute little plantain squirrel (Callosciurus notatus) with some kind of nut in its mouth among the bushes. What a nice way to end my trip there :)

The next time I'm here, I'm certainly going to get a few more friends with me to properly explore this little mangrove. It's really a wonder that despite all the development around the area, this little pocket of nature still managed to survive so well! Certainly hope that it will stay this way for years to come.

Thursday, January 22, 2009

Sungei Buloh on 22 Jan 2009

I was back at Sungei Buloh Wetland Reserve today to conduct a guided walk. We reached rather early, and so I had a bit of time to look around while waiting for the students to arrive.

The Sonneratia caseolaris tree has a few flower buds. Seems like it may bloom any day.

At the main bridge, SY, KS and I saw a smooth otter (Lutrogale perspicillata) jumping into the river and swam towards the sea. Unfortunately it was quite a distance away from us, and by the time I took out my camera, it was already too far away to take a clear photo.

While waiting for the students to arrive near the visitors' counter, I saw some movements among the nearby foliage. Taking a closer look, we saw that it was a very pretty green crested lizard (Bronchocela cristatella).

The students soon arrived, and here's my group at the main bridge.

There were lots of Malayan water monitor lizards (Varanus salvator) under the bridge. With a muscular body, strong tail and the ability to swim, this lizard is one of the top predators in the reserve, feeding on all kinds of little animals, such as fishes, crabs, birds, snakes... basically anything that can fit into its mouth, dead or alive.

The stork-billed kingfisher (Halcyon capensis) at the main bridge area was also out hunting for fishes. We saw it swooping down towards the water, and in a quick flash, it's back up on its perch with a fish in its beak.

Since it's still the migratory season, there were lots of migratory birds too. The egrets (Egretta spp.) were the most obvious ones, since they gathered in such a large number and their white feathers stood out really well among the greenish water. Interesting, we noticed whole flocks of them flying over the river, dipping their claws into the water, and sometimes, their beaks too.

So far this was only the second time that I've seen such a behaviour. Were they hunting for fishes?

We also took a walk around the mangrove boardwalk, and one of the first animal we saw there was this pretty dragonfly - Rhyothemis phyllis.

At the back mangrove, we saw lots of plants such as the sea hibiscus, the sea poison, and mata ayam. Didn't took any photos of them though. This is always a problem when I'm guiding, when it can be quite hard to juggle between guiding and taking photo. Managed to take a photo of this Bird's Nest Fern (Asplenium nidus) though.

We went one round around the mangrove boardwalk, and eventually get to the mangrove area, where we saw some of the true mangrove species, such as the bakau, api-api and blind-your-eyes.

We also saw the nipah palm (Nypa fruticans) with a huge fruit made up of many smaller seeds. Also known as the attap palm locally, this is where you get your attap chee for your ice kachang!

Somehow, we did not see many giant mudskippers (Periophthalmodon schlosseri) today. Those few we saw are either soaking themselves in puddles of water, or hiding in the shade. Was it because it's too hot today?

As we were heading back, I saw this sea holly (Acanthus sp.) with lots of white specks on its leaf surfaces. Those white specks are actually salt crystals. Sea holly have adapted to survive in salt water by being a salt secretor - it's able to secrete the salt it has absorbed from the sea water.

And near the sea holly, several tree-climbing crabs (Episesarma spp.) were spotted. During hide tide, they will climb up the trees to stay away from the predatory fishes that come in with the tide. They are able to climb trees as their legs are very pointed and allow them to easily hook and climb up the rough bark of the mangrove trees.

After the walk, we went for a short video show to learn more about the reserve. Here's a group photo taken after the video show.

On our way back out of the reserve, we spotted this huge spider that has a black body without any patterns. Heard from LK that its a golden web spider (Nephila sp.), and the experts suspect it could be a variation of the usual golden web spider (Nephila pilipes). I've never notice this spider before. Guess I was so used to seeing golden web spiders around Sungei Buloh, that I did not pay enough attention to them these days.

Anyway, it was an interesting trip. Sure looking forward to more of these guided walks in the coming weeks.