Friday, February 6, 2009

Exploring Pulau Ubin and Chek Jawa 010209

Mention 'Pulau Ubin' and descriptions like 'popular place to cycle' and 'well-known offshore island' automatically pop into mind. Well, those phrases used to pop into my mind, anyway! Haha.. Since the 1st of February 2009, I have seen Pulau Ubin with new eyes. Before that, I'd only gone there to cycle with friends..and I never knew that I was missing out on so much. Like what Luan Keng said, you really can't see anything much if you cycle; it's just a blur of green interspersed with other colours, and gray, from the track.

Here's a short excerpt from Singapore's Biophysical Environment by Lu Xi Xi, Wong Poh Poh and Chou Loke Ming about quarrying, of which granite quarrying was an integral part of Ubin's past:

"Three major groups of rocks were of economic importance to Singapore in the past. A series of granite quarries were located along the western flank of Bukit Timah and on Pulau Ubin. In 1970, there were 25 granite quarries employing about 1,200 workers. The first quarry on Pulau Ubin opened in the early 19th century and the last quarry closed in 1999. Clays were obtained from the Jurong Formation for brickworks. The Old Alluvium was quarried and the clays were washed in ponds to produced sand. This left behind a landscape of ponds and badly eroded surfaces."

Today, P. Ubin still bears the marks of its past. There are a couple of disused quarries on the island, which are very deep and filled with rainwater. They are dangerous, for obvious reasons, and thus have fences around their perimeter to keep visitors out.

The island is a great for a brief respite from the hustle and bustle of city life. Be a responsible visitor though (by that I mean DON'T poach, litter and create a din)! And if cycling is not your cup of tea, walking around the island is a great alternative...which is exactly what we did :)

At around 8am, the group of us met at Changi Village Ferry Terminal. To get to Pulau Ubin, one has to purchase a one-way ride on a bumboat for $2.50.
Though sunrise was a couple of hours before, it seemed that the last traces of dawn had spilled over into the early morning.

Ahh...

We had our first bird-sighting right at the start of our walk. Eggciting! Haha...

Found out from LK that these are Dollarbirds (Eurystomus orientalis), so called because they have one round white patch under each wings. Like a dollar coin!

If my memory serves me, it was July who pointed out that these two butterflies were mating. Does anyone know the ID of the butterflies?


'Bird-stalking'! It's getting to be one of my fave past-times (you'll see why in a later post). Haha. This is an Asian Glossy Starling (Aplonis panayensis)! Like their name suggests, they have a glossy plumage which shines in the sunlight.

It's not too clear, but the red eye of this Asian Glossy Starling can just be made out.

Further out on the water were two Grey Herons (Ardea cinerea) [Edit] keeping very still. Herons and egrets may resemble each other, but they belong to different genera. They are, however, from the same family of Ardeidae.
A "nappy" tree o.o Missed out on Ron's further explanation on why it has such a nickname. However, according to Wen Qing's blog entry, it's because the leaves are supposedly soft enough to be used as diapers. Au naturel :P Nickname aside, it is better known by its three common names - Lampin Budak, Laping Budak, Jarak Kayu - and its scientific name of Claoxylon indicum.

Lampin - napkin; diaper
Budak - child
Laping - ?
Jarak - distance
Kayu - wood

(Translations obtained from Bhanot's Malay-English Cyber-Dictionary)

A large Common Red-stem Fig (Ficus variegata) tree. Fig plants exhibit a wide variety of growth forms which include trees, climbers, shrubs, bushes, epiphytes and tree-stranglers. Those bunches on the tree may appear to be fruits, but they are actually syconium - a structure in which the tiny flowers of the plant grow. Most, if not all, of the species of fig plants share a mutualistic relationship with fig wasps (family Agaonidae). The wasps pollinate the flowers, while the syconia provide a safe place for the female wasps to lay her eggs in.

This plant was swarming with ants, possibly attracted by a sugary substance secreted by scale insects which the ants consume. Scale insects are white in colour and have no legs when they reach maturity. They are considered to be garden pests as they suck plant sap. Ants are known to transport the scale insects, offering them protection too. A movable living food source, if you like! Another mutualistic relationship :)

Thanks to Siyang for the info (hope I didn't note down anything wrongly)!

The leaves of yet another fig plant. This time its a Common Yellow Stem Fig (Ficus fistulosa).

Red pipe-clearners hanging from a tree! That's what I thought of upon seeing this tree. It's not a tree, but a shrub though. Common names: Chenille Plant, Red Hot Cat's Tail, Red Cattail, Ekur Kuching, Buntut Kucing, Cat's Tail. Scientific name: Acalypha hispida.

Fig plant number 3! If I'm not wrong, this is a Climbing Fig (Ficus pumila). Its other common names are Creeping Fig, Creeping Ficus, Creeping Rubberplant and Ara Jalar.

No prizes for guessing what this is. The large fruit of the Jackfruit tree (Artocarpus heterophyllus) , ready for the picking (that's just a FIGure of speech). Haha..pun intended. Anyway, both the Fig and Jackfruit are from the same family of Moraceae!

Keeping one's volume down is an unspoken rule in the forest, for loud noises tend to scare animals away. Seems like we were quiet and lucky enough to be able to see this rare bird - a White-rumped Shama (Copsychus malabaricus) which is a popular songster. Due to high demand for activities such as the caged bird trade, the shama has become endangered.

References: Singapore Science Centre: ResourcesEducational ResourcesEndangered Vertebrates of Singapore - http://www.science.edu.sg/ssc/detailed.jsp?artid=3890&type=4&root=140&parent=140&cat=249 and White-rumped Shama - http://www.arowana.com.sg/shama/shama.html

I'm aware that the second link is to a webpage on the caged bird trade. Though I'm not for the trade, the webpage does contain interesting information on the shama.

There were many Golden Orb Web Spiders (Nephila maculata) around that day. This is the underside of one such spider.

Though dissimilar in appearance, the arachnid above is also a Golden Orb Web Spider. As you can see from the second pic, its web is huge.

Thanks to Glenda for holding up a leaf of the White-leafed Fig (Ficus grossularioides) so that I could take a pic of its underside! It's evident where this fig plant gets its name from :)

Depending on growth form and where they grow, fig plants may harm other plants. For instance, if a fig plant (such as a creeper?) grows on a tree, it has the tendency to grow downwards, strangling the host.

Another plant where looking at the underside of its leaves reveals the 'mystery' behind its common name. No, it's not another species of fig, but a Silver Back (Rhodamnia cinerea). This plant is a native tree that lives in open, well-lighted places. The 3-veined, directly opposite leaves with the silvery back is a distinctive feature of this species. It hails from the Myrtaceae family (also called the jambu family). [Edit]

A coastal plant, the Fan Palm (Licuala ferruginea) is often grown in homes for its ornamental value.

A Tapioca plant (Manihot esculenta).

One of the first few flowers I learned the name of in primary school was the Hibiscus (Hibiscus sp.) as there were a couple of prominent Hibiscus plants in the just outside the canteen :)

A plant of the Macaranga genus. There are over 200 species in this genus.

The leaf stalk of the Macaranga starts somewhere near the edge of the leaf blade, in the leaf blade itself. The plants are sun-loving and grow where they can get maximum sunlight exposure.

More Golden Orb Web Spiders!

On the right: a tiny male spider (well, compared to the female, it is tiny) on top of the female spider. Males are typically a tenth of the female's size. If not careful, they may get eaten by their mates. Sometimes, a small spider, known as the kleptoparasite, which is around the male's size may be found on the web. The parasites steal food from the 'owner' of the web. Being so much smaller makes them more agile and they can thus out-manoeurvre the big female.

Check out http://en.wikipedia.org/wiki/Kleptoparasitism for more info on kleptoparasitism.

Fondly called the Bird Shit Caterpillar, these are actually the larvae of Common Lime Butterfly (Papilio demoleus).

These orange knob-like protrusions, known as lenticels, on the trunk distinguish this mangrove, Berus Mata Buaya (Bruguiera hainesii), from other species. Edit (LK): The lenticels are found on ALL Bruguiera species, not just B. hainesii. B. hainesii is called Berus Mata Buaya, meaning crocodiles’ eyes because the lenticels are very large.

The Sea Hibiscus (Talipariti hibiscus) [Edit] is a common coastal plant.

Cotton Stainer Bugs (Dysdercus decussatus)! The larvae [Edit] feed solely on the seeds of the Sea Hibiscus. Notice how these bugs have a red head. A very close relative of theirs has a black head instead (scroll down).

These belong to the Beauty Leaf (Calophyllum inophyllum), so called because of the smooth appearance of each leaf. One species is purported to have anti-aids properties. Research is currently underway.

Two species of mangrove ferns are in this pic. The leaves with the rounded tips belong to the Leather Fern (Acrostichum aureum) while those which have are reddish and have a pointed tip belong to Acrostichum speciosum. The spores of the plants in this genus are not kept in sori.

This is NOT a Cotton Stainer Bug, but a Thespesia Firebug (Dysdercus simon). The easiest way to tell apart the two is by the colour of their head. The former has a red head, while the latter has a black head. The Thespesia Firebugs, which are endangered, reside on Portia Trees (Thespesia populnea).

Though not obvious from this photo, this beetle really does have long horns which grow to roughly the length of its body. No wonder it is called the Longhorn Beetle (family Cerambycidae).

This is Chengam (Scyphiphora hydrophyllacea), a mangrove shrub. The leaves are rounded and opposite. Their glossy covering serves to protect them against sea and land breezes as it allows the accumulated salt to be blown away. Comment from LK: I am not sure if Scyphiphora secrete salt like Avicennia does. Nothing is said about salt excretion of Scyphiphora in the literature. The glossiness is probably to prevent water loss.

These are the young leaves of the Chengam. It's not too clear, but there are two leaves sort of pressed together (the vague edge of the leaf behind is just visible).

More mangrove plants! Here are the leaves of the Teruntum Merah (Lumnitzera littorea). They have a small notch on the leaf tip as one of their distinguishing features. Other features include having a red stem and red flowers.

It was only after I browsed through my photos a few times that I noticed something out of the ordinary... See it? It was right under my nose and I didn't see it. Haha.

This is the Indian Fleabane (Pluchea indica), by the way. It is a mangrove associate (refers to plants which are found in the back mangroves but are NOT mangroves).

Though small, this nymph of a Hopper caught our attention due to its bright orangey-red colouration.

Edit: This should be a Blue Glassy Tiger (Ideopsis vulgaris macrina).

Termites mounds are not uncommon in the forest. They should not be confused with mud lobster mounds though. The former is made up of sand while the latter is constructed from mud (what else!).

One of my favourite sightings of the day - a bagworm! There is actually a caterpillar inside the structure, with its front legs and mouth left uncovered. Bit by bit, this animal will build up its case by pasting bits of material (in this instance, plant matter) onto its body. Cool eh! The one that we saw had just stuck a small bit of a plant stem onto its body (first picture, top left). The type of case built varies from species to species. I think it's amazing how this species is able to make such an elaborate helical case (kind of resembles the structure of DNA, don't you think?).

Saw this dead snail along Noordin Beach. Saw an empty shell of the same species again at Changi Beach yesterday (9th Feb). Can't seem to find the ID of this snail online but I did see this shell in RMBR's collection... Wonder if it might be an apple snail (Pomacea sp.) but such snails live in freshwater... [Refer to Ivan's comment]

The oval-shaped black piece is the snail's operculum which functions as its trapdoor.

This nest of stingless bees (Trigona sp.) [Edit] caught our attention when we were about to walk into Chek Jawa (my first time there!!).

The cozy-looking house on the left is the visitor centre...

..while on the right lies Pulau Sekudu.

Edit: This is Chassalia sp., also known as Grains of Rice/Beras Beras/Beras Hitam.

Saw quite a number of these Mata Ayam (Ardisia elliptica) trees that day. Their common name of 'Mata Ayam' is apt as the fruit does indeed resemble chicken eyes. The leaves have a leathery feel. They are native coastal plants. Edit: This is the fruit of Chassalia sp. NOT Mata Ayam.

Now this is the REAL Mata Ayam. Sorry for the mix up!

Seashore Nutmeg (Knema globularia). Oriental Pied-hornbills (Anthracoceros albirostris) feed on the fruit of this tree.

ID of this, anyone?

A fluffy and white caterpillar! So cute xD
Cuteness aside, caterpillars should not be touched for some species are known to have venomous spines. Better to be safe than to be sorry. Did some research online and found that this caterpillar may belong to the family Megalopygidae, and will probably turn into a moth at a later point in its life.
Here's a video of the fluffy white caterpillar in action. Enjoy!

video

My camera ran out of battery soon after we set foot in Chek Jawa :( So Agnes helped to take the following shots. Thanks!

The Giant Mudskipper (Periophthalmodon schlosseri) is one of the species of mudskippers that can be found in Chek Jawa. The two black stripes running the length of their body is their most distinctive characteristic.

Commonly confused with the Komodo Dragon (Varanus komodoensis), monitor lizards are actually their close relatives and belong in the same genus. This one here is a Malayan Water Monitor Lizard (Varanus salvator). Whenever I see a monitor lizard, I inadvertently recall the time when I was out kayaking with friends last year along the waterways which cut through the mangroves of Pulau Ubin. As we were paddling, we saw a number of dead, bloated monitor lizards which had become entangled in nets left by the bank. The nets looked pretty old and quite a lot of leaves had become snagged too. One word: irresponsible.

I don't want to end this entry on such a sour note so here's a pic of Jarum Jarum (Ixora congesta) to brighten things up! The larvae of the Knight butterfly feed on this plant so no wonder...

...we had the chance to see the adult which has distinctive patterns on its wings. At least three different subspecies can be found in Singapore, with subtle differences in markings. Found an interesting scientific paper on the Knight (Lebadea martha malayana). Read it at http://rmbr.nus.edu.sg/nis/bulletin2008/2008nis183-189.pdf.

Thoughts:

There's so much diversity in Singapore, but it often goes unappreciated. What's more, it's often abused by activities such as poaching. I know this is gonna sound real cliched, but I sincerely believe that if we each do our part, we can make a difference...

Acknowledgements:

Thanks to Luan Keng, Ron, Siyang and July for the info during the walk!

For this post, I referred frequently to ria's free conversion of print to web for conservation, nature info (http://www.naturia.per.sg/), NParks FloraWeb (http://floraweb.nparks.gov.sg/index.jsp) and mangroves of singapore (http://mangrove.nus.edu.sg/).

Thanks to LK for the amendments! :)

Notes:

For more about this adventure, do visit these blogs:

http://tidechaser.blogspot.com/2009/02/exploring-pulau-ubin-with-rmbr.html
http://uforest.blogspot.com/2009/02/exploring-ubin_01.html
http://wherediscoverybegins.blogspot.com/2009/02/discover-ubin-on-2-feb-2009.html
http://midori-no-michi.blogspot.com/2009/02/rmbr-01-pulau-ubin-island-of-granite.html

I'm already looking forward to the next adventure in the wild :)

2 comments:

  1. I believe that those yellow shells are indeed from the apple snail (Pomacea canaliculata), an introduced species. I've found quite a large number of dead specimens along the beach at Changi next to the Ferry Terminal.

    I suspect someone's been using them as fishing bait, or releasing the snails in an act of 'fang sheng'.

    ReplyDelete