Saturday, August 29, 2009

Birds in the Neighbourhood

Crows? Oh, definitely. Mynas? You bet. Ah! Sparrows too.

Most, if not all of us, have definitely seen or heard these birds; their calls punctuating the rhythm of our daily lives. While walking to school, it’s a one hundred percent guarantee that I surely will encounter Rock Pigeons (Columba livia). Whether perched on top of a lamp post or gathered in flocks (sometimes in the middle of a walkway when food has been thrown out), upon seeing them, my brain inadvertently screams ‘Avoid, avoid!’ for fear that I will be on the receiving end of their dive-bombing activity (read: pooping).

Birds, well, are birds, and they are just doing what they do best – being birds – albeit in the city. I have lived in the same neighbourhood for close to two decades, and until recently, my knowledge of birds was limited to crows, mynas, sparrows, pigeon and that unknown yellow bird (Black-naped Oriole). Airborne birds were relegated to the category of ‘those little black splotches flying high above’. It’s amazing to find that there are so many different kinds of birds living alongside us, after all. Most are shy and prefer to maintain their distance from people, so they may be heard (eg. Collared Kingfishers, Asian Koels, Gerygones), but not often seen unless one seeks them out. Of course, there are also chance encounters with our feathered friends…

…I was rushing for time; the bus was on its way. As I rounded a corner, something darted into the foliage of a Chiku tree (Manilkara zapota) with a lot of rustling. My curiosity got the better of me and I just had to look. To my utter surprise, I saw a *female Pink-necked Green Pigeon (Treron vernans) perched on a branch and eating the fruit. Wow! I was about a metre away and thus had a really good look. I’ve frequently encountered them in Kent Ridge but that was my very first time seeing it in my neighbourhood (after nearly twenty years…sigh). While fervently hoping that it wouldn’t fly away so quickly, I hurriedly got out my camera and managed to catch a few shots.

Perched on a branch, blending in almost perfectly with the leaves (indeed, I got a few weird looks from passers-by), the bird rapidly tucked into its meal. It would scoop up the soft flesh with its beak, going almost vertically to do so (as in the picture), and then right itself, throwing back its head slightly to swallow the bit of fruit.

The PNGP with the bit of fruit in its beak :)


Down it went again...

The pigeon continued to feed in such a manner for quite some time. It was a delight to watch :) though I can only hope that I wasn't disturbing its meal (the encounter occurred at around 4 I guess you can say that it was tea-time?). Too bad I didn't get a shot of the bitten fruit... I did walk around the tree to look at it though and saw that a quarter or more of it had been eaten. (In case you were wondering, I did catch the bus in the end but had to do a mad dash for it. Hehe.)

So what else can one spot in the neighbourhood? A short stroll around a park in the evening recently led to sightings of a Yellow-vented Bulbul (Picnonotus goiavier) and a tailorbird (probably a Common Tailorbird - Orthotomus sutorius). Check out gopalarathnam_v's photostream on flickr, as well as Ingo Waschkies gallery on PBase for amazing shots of the Common Tailorbird.

Here's a list of the birds that one can commonly see/hear in urbanised areas in Singapore:
1. House Crow (Corvus splendens) - not to be confused with the Large-billed Crow (C. macrorhynchus) which is native to Singapore
2. Javan Myna, also known as the White-vented Myna (Acridotheres javanicus) - another introduced species
3. Common Myna (A. tristis) - these are less abundant than their introduced counterparts, having faced competition for resources from them. These mynas have a reddish-brown body, unlike the largely black plumage of their relatives
4. Eurasian Tree Sparrow (Passer montanus)
5. Rock Pigeon, also known as the Feral Pigeon (Columba livia)
6. Black-naped Oriole (Oriolus chinensis) - I always think of the song that goes "...yel-low bird, high up in the ba-na-na tree..." when I see them
7. Collared Kingfisher (Todirhamphus chloris) - look out for a streak of blue whizzing by!
8. Asian Koel (Eudynamys scolopacea)
9. Golden-bellied Gerygone (Gerygone sulphurea) - thanks LK for the ID! For many years I have listened to its wheezing call and never knew its source. See Paul Huang's photos of this shy bird.
10. Oriental Magpie Robin (Copsychus saularis)

Birds in the photos above (from top to bottom): Javan Myna, Little Tern (Sterna albifrons) and Pink-necked Green Pigeon.

*Unlike their more commonly sighted counterparts, the Rock Pigeons, which feed on a wide range of food, Pink-necked Green Pigeons are frugivores. They also exhibit dimorphism, with different colouration between the sexes. Males are more colourful than females. Most noticeable would be their pink-purple neck and upper breast, as well as an orange lower breast. Females, as shown in the pictures, mainly have green plumage.

Sunday, June 21, 2009

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 get the idea. Perhaps the following associations will help:

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

- 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

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)

Thursday, May 14, 2009

Braving the Rain at Pasir Ris 140509

Even before the trip started, KS informed us of the impending storm that was blowing over from Sumatra. We could see dark clouds gathering, but decided to start exploring anyway.

Very happy that there were quite a number of 'firsts' for me today again :) Starting them off was this peanut worm (Phylum Sipuncula). They are called peanut worms as their skin, when contracted, resembles the texture of a peanut shell. More on different kinds of worms soon. Haha.

As I walked on, I decided to take a look at one of the many tidal pools. Though there didn't seem to be anything interesting at first glance, movement soon caught my eye. A piece of shell was moving when it had no obvious reason to (there was no water current in the pool). I was pretty sure that a Leaf Porter Crab (Neodorippe callida) was the cause, and yeah, the little crustacean indeed had taken refuge under the shell.

When I flipped the shell over, the Leaf Porter Crab kept really still (playing dead, perhaps?) while lying wrong side up. After several moments, with its legs twitching into action, it righted itself and proceeded to scurry under the shell.

I remember that during the biodiversity practical we had in school, we caught a Leaf Porter Crab - a large specimen it was too! It was carrying a small rock around, a most peculiar sight.

In the same pool, there was a lone Striped Bead Anemone.

Even broken shells are useful! Making this broken shell its home was a small hermit crab.

Further up the shore, I saw many Black Sea Urchins (Temnopleurus toreumaticus). Many were tangled in the seaweed. Tried to rescue a few that were stranded..but there were just too many. Like KS says, we should let nature run its course..

The two pictures at the top show a test - its skeleton - of a Black Sea Urchin. The bottom two pictures are of a live sea urchin. As always, there is a banded worm curled around the mouth of the echinoderm. When flipped over, the beak-like structure of its mouth is visible. It is called the Aristotle's lantern after Aristotle (a famous Greek philosopher) who first described it.

More echinoderms, this time a ball sea cucumber (Phyllophorus sp.). Found it among the seaweed and brought it down into the water. Got a bit of a shock when I turned it over and saw a small crab scuttling over the sea cucumber (pic on the left).

This Mini Carpet Anemone (Stichodactyla tapetum) was the only one that I came across. Wonder if this anemone has any mutualistic relationship with shrimp or nemos. In the picture on the left, a prickly ball sponge can be seen. Both organisms may look harmless, but they should not be handled. Anemones have stinging cells and sponges have spicules which can easily get embedded in one's skin.

Just beside the carpet anemone was a large rock. In one of the recesses of the rock, water had collected. Though the surface of the water was calm, some current was being generated within. Intrigued, I squatted beside the rock for some time and caught the following sequence of pics.

It's a strange feeling when a Thunder Crab (Myomenippe hardwickii), stares at you with one red-lined green eye. It would inch slightly out of the hole, raise its left pincer out of the water and retreat quickly. At one point, it even stuck its eye out of the water. The water was rather murky, but I could see some feathery extensions from its mouth which were waving about in the water as the crab generated a current. What could these extensions be? I would have liked a clearer look, but did not want to disturb the crab (further).

These yellow egg cases are rather commonly seen on rocks along the shore. They belong to a mother Spiral Melongena (Pugilina cochlidium), a mollusc which is encountered rather frequently.

Okay, it's time for the worms! As you can see, I was rather fascinated by these worms. They were writhing about the area just behind the Spiral Melongena eggs.

At first, they appeared to be connected. Note their light blue and black colouration.

Subsequently, they moved apart. Hmm..were they mating?

Here's a close-up shot of one of them...

...and another of the worm on the right. Can't find their ID =X

When while along, I glanced at a patch of seaweed and noticed this small crab with long eye stalks. It's probably a sentinel crab (Macrophthalmus sp.).

This bivalve shell is really pretty with its different band of colurs. Wonder what mollusc it belongs to.

More molluscs! This time gastropods. These are Tiger Moon Snails (Natica tigrina) which secrete sand collars to lay their eggs. As you can see, the two moon snails on the left were engaging in some strange (maybe it is just strange to humans) behaviour. One was enveloping the other with its muscular foot.

Ah! The highlight of the day has to be the two octopuses (Family Octopodidae) which sharp-eyed ZL spotted. This small smooth headed octopus was pulling itself along the spoon seagrass. We later brought it down to the water.

It bunched itself up.

Octopuses are able to change colour and this one did! It was purplish-gray when among the seagrass and changed colour to match its new surroundings.

ZL spotted the second smooth headed octopus as well. It was noticeably bigger than the first. One of its tentacles was shorter than the rest, probably as a result of injury.

This purple sea cucumber (is it a purple under-a-stone sea cucumber?) was firmly stuck to a rock.

Back to worms. Haha. Might this be a bristleworm?

This really small snapping shrimp (note the enlarged pincer) was keeping very still when we chanced upon it.

This prickly sponge had anchored itself to the side of a rock.

At the strand line, a lot of seaweed had washed up along with these blob-like creatures. Can't say for sure what they are, but they might be ascidians. Within them, petaloid patterns were evident.

Ria found this test of a heart urchin (Order Spantangoida) just as we were about to leave. Unlike other sea urchins, heart urchins lack the Aristotle's lantern structure.

For more on today's trip, check out Ria and KS' entries at and respectively.

Note to self:
Put spare clothes in a waterproof case next time. As I'm actively cutting down on plastic bag usage, I decided to just stuff my clothes in my bag. Not the best idea coz that set got wet as well. Prolly I should reconsider changing my stance on plastic bag usage to 'use when necessary'.