10 Fruit Trees of Pulau Ubin 200609

Some RMBR volunteers met up on Saturday morning for an outing to Pulau Ubin cum durian feast. More about that in a later blog post! In this entry, ten fruit trees of Pulau Ubin which we saw will be featured. In horticultural usage, 'fruit tree' refers to a tree whose fruit is used for human consumption. So even though all flowering plants bear fruit, not all are called fruit trees. And 'trees' can be a misleading term...

The first fruit tree that we saw, which, at this time of year, is terribly hard to NOT notice was the Rambutan (Nephelium lappaceum). When I was a kid, I used to be unable to tell the difference between Lychee (Litchi chinensis), Longan (more than one species) and Rambutan. Well, there're all from the same family of Sapindaceae! Even now, I keep thinking that Lychee is Rambutan..and Longan is Lychee..you get the idea. Perhaps the following associations will help:

Rambutan - red and hairy (rambutan, derived from the Malay word rambut which means hairs)

Lychee - red and NOT hairy

Longan - brownish-yellow and NOT hairy

Rambutan trees grow in countries with tropical climates. They are evergreen ie. having leaves all year round. Some trees are dioecious while other are hermaphroditic.

The second fruit tree that we came across was that of the Custard Apple (Annona squamosa) (note: the common name refers to all three species in the genus Annona). This variety hails from the family Annonaceae which grows well in warm, humid climates. According to this website, "[t]here is a thick, cream-white layer of custardlike, somewhat granular, flesh beneath the skin surrounding the concolorous moderately juicy segments, in many of which there is a single, hard, dark-brown or black, glossy seed, oblong, smooth, less than 1/2 in (1.25 cm) long.". I remember eating a custard apple a very, very long time ago and thus cannot remember how it tastes like. Probably was not fond of it which explains why I've not eaten it ever since.

What's a durian feast without durians? In Pulau Ubin, a noticeable number of Durio zibethinus trees grow just along the main trail. When not fruiting, this tree, which hails from the family Malvaceae, can be distinguished by its leaves which have a bronze underside. There are 30 recognised Durio species but the one mentioned here is the variety which is available in international markets.

The durian has long been nicknamed 'the king of fruits'. The ripe fruit has a pungent, distinctive smell and comes in multiple segments. The seeds, found in shallow recesses in each segment, are covered in a soft and custard-like flesh, ranging from cream white to yellow and even red, depending on the species. Apart from the smell, the other distinctive feature is, of course, the husk, which is very prickly. Wallace, a famous naturalist, apparently said that for one to appreciate durian, he or she has to eat it three times. I used to love eating durians back when I was a kid but have since assiduously tried to avoid them (though what possessed me to eat some on Saturday is beyond me...).

Contrary to the title of this blog, the banana (Musa spp.) is not a tree but a herb - the world's largest herb, in fact. Basically, herbs are plants which have non-woody stems. The humble banana (family Musaceae) has its origins in Southeast Asia and over time, with the rapid spread of globalisation, it became well-known to the world. Musa comprises both dessert bananas (what we eat in Singapore) and plantains. The former is eaten raw while the latter has to be cooked or processed in other ways. Plantains have lower water content, making them drier and starchier than fruit bananas. They typically form a staple in the diets of people living in places such as Central America, the Caribbean and Peru.

The picture above shows the main stalks of banana plants which grow from rhizomes underground. In due time (if not already), the terminal inflorescence will grow out from the top of the stalk, and bear fruit. Each stalk produces one huge flower cluster and then dies. New stalks then grow from the rhizome. In summary, the growth of one main stalk is as follows:

Rhizome (produces more than one shoot but most are cut back in order to allow energy to be channelled to fruiting of the main stalk) -> new shoot (typically called a sucker) -> large leaves -> terminal inflorescence -> fruiting (bunch o' bananas) -> main stalk dies -> cycles repeats itself (main stalk forms from a new sucker of the same rhizome)

I was really confused about the whole process of propagation until I chanced upon these sites which can be accessed here and here (good diagram showing the parts of a banana plant). This other website details how the popularity of bananas spread and explains an interesting phenomenon - negative geotropism - which banana plants exhibit.

Hope you aren't suffering from banana overload (like I was). Here are a few more interesting things:

i. fibres are obtained from the stalks which can be made into material (for clothes) and other items such as bags. The pic on the right is a close-up shot of a bag made from banana fibres. It was given out by the Filippino restaurant, 7017 Flavours, on their anniversary. The staff there wear uniforms made from the fibre too.

ii. banana hearts (ie. male banana flowers) are used in dishes like rojak. They look like pink curlicues once cleaned off of gravy.

This pretty pink-streaked flower belongs to the Starfruit (Averrhoa carambola) (family Oxalidaceae).

Here, you can see the developing fruits which still have some way to go before ripening. The common name comes from the appearance of the cross-section of the fruit. It closely resembles a star, with both its (yellow) colour and shape.

Often eating with sour plum powder, the guava (Psidium spp.) (family Myrtaceae) is another fruit that is a favourite with locals. Apart from eating it fresh, guavas are also consumed in their preserved form. Personally, I prefer the preserved ones even though they remind me of curled-up pieces of dead skin (haha!).

When crushed, the leaves of this tree give off, what else, but a guava-ish smell.

I was surprised to see Cacao tree (Theobroma cacao) (family Malvaceae) growing in Pulau Ubin. Didn't think that they grow in this part of the world. Theobroma means 'food of the gods' in Greek, and indeed, processed cacao beans are what gives us cocoa from which the much prized chocolate is made. Each cacao pod contains 20 to 60 seeds (usually called beans). These contain a high percentage of cocoa butter, a fatty substance.

You'd think that with cocoa being so prized and all that everything about the plant must be grand. While flowers of many plants are pollinated by butterflies/moths or bees, cacao flowers are pollinated by...flies. Clearly, flies are not to be looked down upon.

While taking a break from writing this blog entry, I munched on some coconut candy - a sweet confection that is made from grated coconut. Coconut trees (Cocos nucifera) hail from the palm family of Arecaceae (Palmae is now considered taxonomically invalid), and are the only species in the said genus. Nearly everything about them is useful, from the nuts to the leaves.

Coconut palms are often seen growing by the coast for they are dispersed by water. The fruit itself has a hollow cavity that is filled with a liquid commonly called coconut water. The air-filled space allows the fruit to float on the surface of water.

I can't help but think of the Coconut Crabs (Birgus latro) upon the mention of Coconut Palms. These crabs have been observed to crack open coconuts whether by using their chelipeds or climbing up a tree and subsequently dropping the fruit to crack it open. Read more about their behaviour here and here.

This plant here is not a tree, but a climbing vine. The luscious (probably unripe) fruit here is a passion fruit (Passiflora spp.). Not sure if this is the kind that is consumed though. When ripe, the fruit is harvested and the juice, along with the pulp-covered seeds, are used in a variety of ways. In Singapore, it is not uncommon to find bubble tea that is passion fruit-flavoured.

Being a climbing vine, the plant has tendrils which it twines around a support structure. When mature, the evergreen leaves are deeply 3-lobed and finely toothed.

I 'expired' rather quickly that day and left out two other fruits which LK pointed out, namely, the Jackfruit and Nutmeg. After rooting around, I realised that I did have the resources to finish this entry (with a number 11 even), after all :D

Here we go...

Another fruit with a pungent smell is the Jackfruit (Artocarpus heterophyllus). It is the largest tree borne fruit in the world. The leaves are oblong, oval, or elliptic in form, 4 to 6 inches in length, leathery, glossy, and deep green in color. Juvenile leaves are lobed. This tree is commonly planted in and around housing estates. It is closely related to the Cempedak (Artocarpus champeden). Currently, I am not able to differentiate the two... Both hail from the family Moraceae.

Photo taken from nunukphotos.com

I'm not sure which species of nutmeg (family Myristicaceae) the ones found at Pulau Ubin belong to, but if I needed to hazard a guess, it would be Myristica fragrans, which is a commercially viable species.

The seeds are dispersed by big birds (which have bigger beaks and able to swallow larger fruits) like Imperial Pigeons and hornbills. For germination to occur, the seed has to swallowed and passed through the gut of the bird. Only then can the astringent mace (lace-like covering) around the seed be removed. With the dwindling numbers of big birds in Singapore, the nutmeg is suffering.

Nutmeg is used in cooking and baking as a flavouring. The powdered form available in supermarkets is obtained from grating the seeds. The mace is also used. Both impart a similar flavour.

Quite a few of the fruits featured are heaty, such as the Rambutan, Durian, Jackfruit and Cacao. Starfruit is cooling.

To recap, here is a list of the 10 fruits featured:

1. Rambutan (Nephelium lappaceum)
2. Custard Apple (Annona squamosa)
3. Durian (Durio zibethinus)
4. Banana (Musa spp.)
5. Starfruit (Averrhoa carambola)
6. Guava (Psidium spp.)
7. Cacao (Theobroma cacao)
8. Coconut (Cocos nucifera)
9. Passion Fruit (Passiflora spp.)
10. Jackfruit (Artocarpus heterophyllus)
(Additional) 11. Nutmeg (Myristica fragrans)

Reality Check.

I feel heartened every time I read or hear about people doing their bit for nature. It's great that ordinary folk spend time educating the public and channelling their energies into conservation work. Then there are those who don't care and these people really get my goat.

After Pedal Ubin, we were in high spirits as we headed toward the jetty to take a bumboat back to the mainland. As it was low tide, the mudflats were exposed and we spent some time looking down for signs of life from our position on the walkway. Walking slightly ahead, I suddenly stopped short at the sight of people crouching down on the mudflats. Okay, no reason to get alarmed yet. When I got closer, the sight that lay before my eyes (and for anyone who bothered to look) confirmed my earlier suspicion.

A group of five (a mix of both males and females), with at least one wielding a long stick and a plastic bag, were nonchalantly trampling on the mudflats and destroying the burrows made by the crabs. Destroying the mudflats by trampling? Hardly. With their long stick, they proceeded to insert the end into burrow after burrow. As they pulled the stick back up each time, a lot of mud was dislodged intentionally. Disgruntled that no crabs were getting caught, they repeated the process again. One of them even took out his camera to take his friends in action.

The above happened in a matter of seconds, and by that time, the others (some guides and participants who were heading back to Changi Village) had gathered and they started calling verbal deterrents to the group below. Mindy and I informed the NParks guy at the information kiosk, who grudgingly roused himself from his nap to entertain us. As we told him what we saw, he pointed to the map of Pulau Ubin laid out and said that only Chek Jawa is a restricted zone..here we (meaning NParks) have no power..can only stop them if they're damaging or killing things (I specifically remember him giving seahorses as an example). In short, he made it sound as if people are free to do what they like in the areas that are not protected.

Clearly those people were causing damage!

We finally got him to follow us after some time (didn't seem willing to leave his post), but by then, we only saw the backs of the intrepid hunters who had finally decided to leave.

Okay, so NParks has no power to stop people from damaging areas that are not protected. Seems reasonable enough, for not ALL areas can be protected. What if endangered animals happen to live on shores/in areas that have no protection? Can poachers poach all they want?

Where do we draw the line?

The NParks staff have the option of telling people to cease their detrimental activities, but otherwise, nothing else can be done. I just called the NParks management office to ask for their take on this matter. Much of what was told to me I already heard from his fellow colleague, except that he put it across in a much nicer way. Something new to me was that the area in question falls under the jurisdiction of the LTA and even HSBC.

I asked the guy what NParks is doing about areas with no protection. His answer was that they are trying to get something done but there are politics involved. Not that word again, please.

What can we do to help?

The matter with red-tape aside, I can see why education is imperative in spreading the message of conservation. Ignorance can be attributed to the harm humans inflict and this can be reduced through education. Don't wait around for authorities to implement some policy or kick off some campaign to 'save the Earth'. It can start on the individual level, if you let it.

Did you ever collect sea shells when you were a kid? For many people, myself included, I thought that it was a harmless activity. On the day that I found out shell collection had negative effects (depriving hermit crabs of their homes, etc), I opened my mouth to start a reply but closed it when I realised that all I had to say started with either "I didn't know" or "I didn't think".

Pedal Ubin! 070309

Moments after we set foot onto Pulau Ubin, a steady drizzle started which threatened to dampen our mood. Luckily, the rain abated quickly and we soon embarked on our first Pedal Ubin experience :D

Dark clouds were starting to obscure the sun...(played with my photo-editing programme).

Saw quite a lot of these birds wheeling overhead. They are Pacific Swallows (Hirundo tahitica) and are resident birds.* I've not been able to get a close look at them yet...

Before the Toddycats! guides brought us out, we were asked to test out our bikes (by playing with the gears, etc). Each group had around 13 participants and set off in intervals.

While waiting outside the Pulau Ubin Volunteer Hub, I turned my attention to the occasional bird in the vicinity. Blurry pic (argh!) of what looks like a Yellow-vented Bulbul (Pycnonotus goiaivier).

In no time, we were off and peddling hard to get to our destination (the destination of each Pedal Ubin trip varies) - Chek Jawa (CJ)! Upon reaching the CJ gates, we dismounted and parked our bikes in the bicycle stands provided, proceeding to advance on foot.

On our way in, we saw a couple of these mushrooms. If conditions are moist and humid, expect fungi! Based on their morphology, these mushrooms here are probably basidiomycetes (mushroom or club fungi). (ID?)

While exploring round the back of House No. 1 (CJ's visitor centre), Ze Lin spotted this pair of mating bugs. Are those droppings as pointed out by Samson Tan? (ID?)

ZL (with his sharp eyes) alerted us to this very well-camouflaged caterpillar. It was huge: around 8 cm long and 2 fingers wide o.O I remember there being comments like, "What kind of butterfly will it turn into?". I'm wondering too!

Identity revealed by Ron. It's the caterpillar of an Atlas Moth (Attacus atlas).* The moth is indeed big, with a wingspan of around 25 to 30 cm. Wow!

Just a stone's throw away was this much smaller white caterpillar with 'spikes'. (ID?)

At the front of House No. 1, there is a huge tank which houses marine animals that need rehabilitation. Currently, the tank is not in use as it's undergoing 'upgrading'. However, many terrestial bugs have fallen in and subsequently died, like this Scarab Beetle (Family Scarabaeidae).*

If memory serves me, those leaf-like 'pouches' are actually the modified petals enclosing the seed. Wrong info!

Those aren't modified petals, but modified leaves called bracts and belong to Flemingia strobilifera.* According to Dictionary.com, a bract is a modified leaf growing just below a flower or flower stalk. Bracts are generally small and inconspicuous, but some are showy and petallike, as the brightly colored bracts of bougainvillaea or the white or pink bracts of flowering dogwoods.

I believe this is a weaver ants' nest.. (ID?)

The view from the top of the Jejawi Tower in Chek Jawa.

As we were making our way down from the tower, this bird caught my eye. (ID?)

Curious indeed! This spider web was strung near the supporting pillars on the tower (forgot which storey). What are those lumps? Hmm..bundled up prey?

Mindy noticed the spider eating one of the lumps! (ID?)

Mud Lobster mounds can be found on both sides of the Chek Jawa Boardwalk. Though the mounds are common, the Mud Lobsters (Thalassina anomala) themselves hardly ever make an appearance.

The Nipah Palm (Nypa fruticans) is the only true mangrove palm. Its immature fruits are used extensively in desserts like Ice Kacang, and are commonly known to us as attap chee. Apart from satisfying one's sweet tooth for attap chee, this plant is commercially important as its parts - such as the fronds and sap - are used widely.

Mindy spotted this strange-looking spider. Got a clue from Samson Tan about its identity. Following it, I think this spider may be a Big-bellied Tylorida (Tylorida ventralis), a species which is falls under the Big-jawed Spiders family of Tetragnathidae.

The inflorescence of a Nipah Palm.*

The shape of their web give tent spiders (Cyrtophora spp.) their name.

Pausing for a rest on a Mud Lobster mound was this Dusky-gilled Mudskipper (Periophthalmus novemradiatus).

For more info about mudskippers in general (Family Gobiidae), check out http://mangrove.nus.edu.sg/guidebooks/text/2106.htm.

Scuttling about were the tree-climbing crabs (Episesarma spp.). One of the our guides, Tina, I think, mentioned how it's weird that she doesn't ever see the crabs climb the trees at CJ though they can be caught in action at Pasir Ris/Sungei Buloh.

Ron says: "You will see the tree-climbing crabs climbing trees when it's high tide. The crabs climb trees to escape from predatory fishes.".

A couple of leaves of the Sea Hibiscus (Hibiscus tiliaceus) were covered with a moving mass of Cotton Stainer Bug (Dysdercus decussatus). They are said to group together for the purpose of finding mates.

As we continued walking along the boardwalk, ZL gestured for Wanwei and I to come over. Our approach caused this crab to take cover, but luckily it emerged a few seconds later.

Later on, at NUS, I showed Ron the pic and found out more about them. Prof Peter Ng said that they look like Uca triangularis (Uca is the name of the fiddler crab genus) while Ron and LK provided the following info: the burrows (seen above with a crab guarding it) are known as chimneys and are built by the females. As female fiddler crabs do not have an enlarged pincer like the males, they are able to eat twice as fast. With meal times ending quickly, females have more time to build the chimneys which they use to protect themselves (no enlarged claw to fight with).

The chimney-building habit is specific to a few Uca species only. Uca triangularis and Uca paradussumieri juveniles are two such examples.*

Initally, I thought that the two Uca triangularis I caught on camera were females...but upon closer inspection, doesn't the right claw of the crab in the photo above look rather odd? Could it be a male?

This one here, though, is definitely a female.

This looks like the Blue-spotted Mudskipper (Boleophthalmus boddarti).

Looking like a mini ice cream cone was this Creeper Telescope Shell (Telescopium telescopium) lying on the mudflats.

This bug (spotted by Mindy) looks as if it has a smiley face painted on its abdomen :) (ID?)

Saw Mindy squatting by the side of the boardwalk and found out later that she was looking at this mudskipper here! It has red pelvic fins, something which I've never seen before. (ID?)

Is this an ant? Nope! It's a juvenile praying mantis (no evidence of wings). 2 pairs of its legs are on the leaf while its forelegs are held just below the head.* In some species, the nymphs rely on ant mimicry to aid them in their survival. Well, it certainly fooled me!

3 Cotton Stainer Bugs and 1..?!? (ID?)

The underside of a female Golden Orb Web Spider (Nephila maculata).

The species name has been updated to pilipes.*

The tide going out (~0.6 m), and exposing the mudflats...where many male fiddler crabs (Uca spp.) were out.

A closer look at them.

This Common Tailorbird (Orthotomus sutorius) would perch on a branch, twitter a few notes of a song, and then quickly dart to another tree. It hardly kept still!

A second after I took this pic, this Greenish Grass-dart (Ocybadistes walkeri) took off. Thought it was a moth but it's actually a Skipper butterfly like Ron said.

How do you tell a butterfly and a moth apart? For one, butterflies have club-shaped antennae. Find out more info about these creatures here and here.

As Pedal Ubin was coming to an end, we departed from CJ and cycled back to the volunteer hub. On the way back, there was still lots to see!

Can you see me? Twined loosely around a branch of similar colour was this snake. (ID?)

We made a stop at the headman's house where this Blue Glassy Tiger (Ideopsis vulgaris macrina) was flitting about in the garden of sorts.

Translucent wings.

Juvenile rambutan fruits? Far from it, as I just found out from Ron. These are the fruits of the White Mulberry (Morus alba).*

The best description I can think of is 'bright pink furry flower'! This is Cockscomb (Celosia Cristata).*

The young blooms of the same flower.

Pedal Ubin was an enjoyable experience and I do hope to participate in it again! The next one is coming up in June :)

Acknowledgements:

Credits to Mindy for the pics of the two unknown spiders, insect with smiley face on its abdomen and mudskipper with red pelvic fins.

*Thanks to Ron for the IDs and info!

Notes:

I've been using the terms 'insects' and 'bug' interchangeably but there is a difference! Thanks to Mindy for pointing it out!

Got this off Wen Qing's blog: "True bugs belong to the Order Hemiptera (hemi = half + ptera = wing) because of its forewings which are hardened near the base, but membranous at the ends. Its defining feature is its possession of mouthparts which have evolved into a proboscis and forms a "beak" of sorts which is capable of piercing tissues (usually plant tissues) and sucking out the liquids, usually sap.". So..there are bugs, and then there are insects :)