027. Pulau Semakau 2nd Hunt – It’s a whole new world down there~~

With the sunlight piercing through marshmallow clouds up in the heavens and the water swirling cool between my knees, I must say I was tempted to stay rooted and start snapping away. And with my camera safely ensconced within a Dicapac underwater casing, I couldn’t resist dunking my camera every once 2 seconds just to get some sea and sky shots. Though the corners of the images snapped seem to be hindered by the grey outlines of the casing’s edge, it’s all just a matter of cropping it and voila, it’s as good as a real underwater snapshot. ;)

 

 
Amongst the seagrass and algae were sponges with one housing the Hairy Crab (Pilumnus vespertilio) above. Also known as the ‘teddy bear’ crab, the fluffed-up (when submerged underwater) creature triggers a ‘hug me’ reflex in some. >_< The fluffed-up feature (besides eliciting the aww-so-cute-I-wanna-cuddle-it reaction) also serves to break up the body outline, easily passing off as floating debris before the roving eyes of a hungry predator. On terra, their long, silky hairs (sounds like something off a hair shampoo advert.. lol) traps sediment, and thus blending them perfectly with their surroundings [1]!

(top left): In the stream that gently snaked towards the reef, TC found a patch of egg casings hooked atop a blade of tape seagrass.

(top right): Also, burrowed in the sandy bed of the stream was an inconspicuous Sandfish sea cucumber (Holothuria scabra). And just as its common name suggests, the sea cucumber lives in sand and comes out to from its hidey-hole once night falls and the stars twinkle. Did you know that the sandfish sea cucumber is known to harbour symbiotic Pea crabs (Pinnotheres sp.) in its rear ends?  -.-

(bottom left): On Semakau Island, tape seagrass (Enhalus acoroides) covers kilometres of the shoreline. And just like the Sunflower Mushroom Hard Coral, the tape seagrass (so far) is the only species for the genus Enhalus!

(bottom right): Restricted to Malaysian and Singapore in particular (based on the Singapore Red Data Book), the survival of the Noble volute (Cymbiola nobilis) is threatened by its own beauty. Cloaked in orange/yellow/beige with reddish-beige/brown zigzags, the shell is seen somewhat as an attractive accessory. Perfect, more clutter for dust to settle upon.. oh wait, most collectors are usually rich enough to hire servants to do the dirty work. =.= Anyway, it’s unadvisable to collect empty shells from the beach as they are potential homes for hermit crabs that have grown too big for their old homes [2].

(top left): Can’t remember the exact reason, but it’s not right to say male or female flowers (need to flip through my biodiversity notes). Hence, the flower bearing the female sexual organs is large and held on a long stalk. When flooded by the tide, the petals of an unpollinated ‘zips up’ and unzips back when the tide ebbs. It spreads apart to allow easy access to incoming flowers bearing pollen.

(bottom left): While the flowers bearing the female gametes are big, the situation is otherwise for flowers bearing pollen. Looking just like small pieces of white polystyrene or styrofoam, these flowers are produced from a cup-shaped inflorescence that forms at the base of the tape seagrass. With one end water repellent and the other attracted to water, the flower is able 'stand' upright on the water surface (a wet finger-tip too)! This way, the pearly blooms tend to form 'rafts' with all ends facing the same direction. =)

And my find for the day at our transect was the Black Phyllid Nudibranch (Phyllidiella nigra). This black nudibranch with its distinctive pink bumps can often be seen on the southern shores of Singapore, near coral rubble and reef. Indeed, this was where I spotted this lil’ pink one, right at the tip of Semakau reef. This time round, there was no need to worry about avoiding shadows cast by the sun overhead. All I need to do was dunk and snap. I have not felt this excited about taking pictures for quite some time now [3]. :)

And the star of the day, I present to you….

… the Blue-lined flatworm (Pseudoceros sp.) of china porcelain colouration. Gorgeous isn’t it? I was practically leaping with excitement when my eyes caught hold of this tiny gem on the sponge along the sandy shores. It all happened when I was walking back towards the meeting point, and a tiny fleck of blue and white caught my attention.

Usually, this small white flatworm with blue lines is seen on coral rubble near living reefs. Made up of folded edges of the body at the front, is a pair of erect pseudotentacles (as shown in the picture) [4]. As it swept gently across the sandy substrate, my camera followed its every move like the provincial chick (and I mean the one that goes cluck, cluck). Every peer and glance, dip and dive was faithfully embedded onto the digital memory of my A720IS. And with this to commemorate my first acquaintance with DICAPAC WP-510, I can’t wait for my next trip down to Semakau Island!

おねえーさんわ大好き!!  The picture above is dedicated to you, thank you for the lovely gift \(￣ー￣)/

Reference:
1. http://www.wildsingapore.com/wildfacts/crustacea/crab/pilumnidae/pilumnidae.htm

2. http://www.wildsingapore.com/wildfacts/mollusca/gastropoda/volutidae/nobilis.htm

3. http://www.wildsingapore.com/wildfacts/mollusca/slugs/nudibranchia/nigra.htm

4. http://www.wildsingapore.com/wildfacts/worm/polycladida/blueline.htm

026. Pulau Semakau 1st Hunt – Stop & smell the roses! (25th July 2009)

Edited.

Well, metaphorically at least. But that’s not to say that the shores are devoid of flowers. Within the mangroves, sea hibiscus provides a cheery-sunny view with its red yellow flowers. Amongst the seagrass lagoon, when it’s within season, tiny pearl-white beads of the tape seagrass pollen can be seen floating en masse towards its female counterpart (more of it in the 2nd hunt).

Another flower, an even prettier sight to behold when embraced within the lapping waves of the sea, is the anemone. However, these are far from the floral ones that grace the terrestrial fields. Many have said they share a resemblance to each other, appearance-wise. But that’s where all similarity ends. One attracts bees while the other can sting like one. >_< I must say, the fella who was responsible for bequeathing the marine creature its common name must had fancy plants quite a bit. Even with the images below, it takes quite a bit of an imagination to be able to see where the similarity overlaps.

Once equipped, it’s towards the shores we made our way as the sun slowly rose from its mauve folds of comforters. This time round to Semakau Island involves putting on our “hunting caps” and keep a sharp eye for any lurking creature, whether its beneath sandy terrain of soggy sponge. Once found, the creature (or its species) is kept tabs on via keeping a survey sheet. These data would then be used as a baseline for monitoring purposes besides contributing to public use via the Project Semakau website. All this serves to enhance the island’s value as an education-cum-conservation site.

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Some of the first few creatures that made it to the data sheet my group partner, Tiong Chin and I was in charge of was these nerites molluscs. To the untrained eye, a glance of the top may reveal few but once flipped to its bottom, the markings and bumpy edges tell a different story for each species. However, to a conchologist (mollusc and shell expert), the shape or the texture are a big enough giveaway of their identity.
Edit-
(left): Previously thought to be a nerite turned out to be a Toothed Top Shell Snail. Translated literally as the ‘One-toothed lip’, the Monodonta labio indeed has a single, tooth-like protrusion at the lip of its opening. And unlike the thick trap-door which the nerite on the right possesses, the M. labio has a thinner trap-door (aka operculum) that is made of corneous or horny material. Flexibility-wise, this allows the snail to withdraw deeper into the dark corner inside its cone-like but asymmetrical shell – not from the curious glances of a piqued audience, but from the voracious prying of shore-inhabiting crabs.

(right): Compared to the snail in the left picture, nerites like this Nerita chamaeleon has a thicker trap-door. In fact, the variable hues in which a operculum can  come in plays an important part in nerite ID. However, the Nerita chamaeleon or the Chameleon nerite earned its namesake for showing great variation in shell markings and colouration. Thicker in operculum relative to the Toothed Top Shell, the shape of the nerite is also different as in it sports a semi-marble figure. This unique semi-globular probably helps by extending its lifeline a little. Forget about eating, what use is lunch if it keeps slipping from one’s crab-by grasp? >_<

During the low tide, these nerites lead an ‘idle’ life and creep about slowly (if any at all) on the rocks garnished with lichen. In fact, their favourite low-tide spot would be one where the food source is readily available. Also, this must also include areas above tide line as no nerite in their right mind would enjoy being the next dish for quicksilver gobies etc [1].

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Next up on the introduction list, we have members of the Family Cnidaria. Never mind their tendency to be slow-moving (sessile for some), they can still ensure their survival on the reefs. Thank you very much. On the left – from Order Actinaria – the Banded bead anemone looked fairly similar to the coffee sweets I used to suck when I was a kid. When the tide ebbs, the tentacles of this true anemone are tucked into its body column, making it look like either blobs of glassy, spat-out coffee candy or beads of jelly. :) Although they can often be found in clusters, the banded bead is a lone wolf, a solitary polyp to be precise [2].

(right): Also Order Actinaria, the Giant carpet anemone (Stichodactyla gigantea) was next to be seen. With its capability to span about 40-50cm in diameter, the giant carpet anemone rivals the Haddon’s carpet anemone (Stichodactyla haddoni) in size. Covered in short tentacles so that it looks like an unkempt carpet, the giant carpet anemone has a folded oral disk (as can be clearly seen in the picture). Although it resembles the Haddon’s somewhat, it differs by lacking the fringe of long-short tentacles which the Haddon’s possess at its edge [3].

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Another characteristic that separates the Giant carpet anemone (Stichodactyla gigantea)  from Stichodactyla haddoni is that the thin-tentacled giant carpet has a flashy underside compared to the plain one of the former. From shocking pink to royal velvet, rows of verrucae make eye-catching patterns on what can be termed as a splashy background [3]. Verruca, for your information, is a small, flattish, wartlike prominence –usually found growing at the bottom of the foot – and not the tantrum-throwing, greedy kid from ‘Charlie & the Chocolate Factory’ (though her existence could be likened to one).In fact, according to wiki, Dahl claimed that "Veruca Salt" was the name of a wart medication he once had in his medicine cabinet. Wicked sense of humour, he has (always had a fondness for his books)!

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(left): Found stuffed between a rock and a hard place was the Branched tentacle anemone (Phymanthus sp.) (Order Actinaria). In fact, that’s where they are mostly seen, wedged between crevices! :)

(right): Characteristic to these sea anemones are the fine branching located on their tentacles. As can be seen from the image, the slaty-grey body column has longitudinal rows of verrucae (just like the Giant carpet anemone, but less flamboyant) in white. When disturbed, it tucks its tentacles into the body column like so (the picture shows it’s half way there) [4].

Another household similar, an untidy mop this time round which we crossed paths with was the Swimming anemone (Order Actinaria). Though it has a pedal disk (the structure which attaches the anemone to the ground), it isn’t very sticky and the anemone can still swim by undulating its numerous manners in a coordinated manner. At low tides like this time, the anemones can be seen lying freely on the ground or attached loosely to the seagrass/algae. They don’t really swim all the much. When threatened, its been said that the anemones will lose its tentacle on purpose as distraction. Now attracted to the wriggling tentacle, the swimming anemone would make its escape (possibly by retracting its tentacles) while its predator’s attention is still elsewhere. Since its generally a slow-moving being, the anemones rely on their harboured photosynthesizing zooxanthellae (a type of algae) for food [5].

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Zooxanthellae-wise, the same can also be said for the Bubble tip anemone (Entacmaea quadricolor) (Order Actinaria). And just like the Branched tentacle anemone, the Bubble tip anemone is generally found nestled amongst hard walls (corals especially). However, the tip does not always appear bulbous but can be inflated at will. If bulbous, the band of white near the tentacle tip would be located somewhat near its “equator”. Not quite sure what triggers the inflation/deflation, though it has been related to the presence of anemonefish [6].

Let’s play a game of “Spot the Sunflower Mushroom hard coral”. How many can you find? =)
Clue: Yotsuba! ヽ(´▽`)/

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Though it has bulbous tentacles not unlike the Bubble tip anemone, the Sunflower Mushroom hard coral (Heliofungia actiniformis) is not a sea anemone but a hard coral of the Order Scleractinia. Free-living in its adult stage, the coral is commonly seen on Pulau Hantu and here at Pulau Semakau ^^v. Uniquely, it’s the only species in its genus Heliofungia and is considered to be the largest of polyp among hard corals. Yes, you guessed it. The entire mass is a single animal!

Besides being mistaken for sea anemones, the Sunflower Mushroom has also been mistaken for the Fungia Mushroom hard coral. However, telling apart these two can be seen using the picture on the left. The Sunflower Mushroom has large, rounded teeth on the skeleton walls (the rounded forms at the top in the middle) while this feature is lacking in the Fungia Mushroom Hard Coral.

 
That’s Tiong Chin there, my co-partner during yesterday’s hunting-seeking session, as he trudged through verdant beds of algae and seagrass as the hunt continued... 

Reference:
1. http://www.wildsingapore.com/wildfacts/mollusca/gastropoda/neritidae/neritidae.htm

2. http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/beadbanded.htm

3. http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/gigantea.htm

4. http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/phymanthus.htm

5. http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/boloceroididae.htm

6. http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/entacmaea.htm

7. http://www.wildsingapore.com/wildfacts/cnidaria/coralhard/fungiidae/heliofungia.htm

Credits: Thank you, Song Kiat for identity rectification :)

025. 7’s Haven for High-fliers (sequel)

Oh my god, I can’t believe that the aftermath of the glimpse I caught yesterday is still sending my tummy-inhabiting butterflies into a frenzy. Okay, so it might not be such big a deal to some, afterall it’s only a myna. ┐('～`；)┌ But mind you, this glossy, black being is not just any canteen-hopping avian. Numerous times, the resounding calls of the Hill Myna (Gracula religiosa) has accompanied me –  just before the mauve skies reflect the first fiery shafts of the sun, and my friends start awakening from their deep-night slumber. Seeing the elusive creature, never mind that it may be 2-300m from me, was the next must-do on my list! Not any clip from the web (doesn’t matter if the resolution is crystal clear and shows even the eyelash), I will not settle for anything less but the real thing. Picky, I know. =)

But before I start gushing on and on about it, I would like to illustrate a bit on the other feathered friends which frequent (some only once in a blue moon, or maybe that’s just me) the verdant settings King Edward 7 Hall and its surroundings have to offer (besides the one that I wrote about previously).

Psittacidae (Family):

Seen on my way to class one day was a couple of Long-tailed Parakeets (Psittacula longicauda). These guys resemble a parrot somewhat, except that parakeets generally have long tail feathers (it’s not just this species as its common name might infer). :) Unlike the female (right), the male (left) has longer tail-streamers. It’s my first seeing this bird after all, and I might just have identified it wrongly. But the Long-tailed Parakeet was my best bet, not only because of its evident red beak…

… the sides of the parakeet’s head is also a reddish-pink hue! And whaddaya know, these birds are also endemic to Peninsular Malaysia and Singapore. Yes sirree, these birds weren’t introduced but instead call the two neighbouring countries their home (besides the regions of Andaman islands, Nicobar islands, Sumatra and Borneo). And interestingly, they usually form groups of up to 20 birds, although it’s also known that at times up to 800 parakeets can congregate, particularly at coastal roost sites [1]. I guess seeing just 2 would either mean that these pair wanted some private time (for chrissake, doing it with 20 pairs of eyes around you could be a lil’ unnerving, but that’s just me, heh) or …. it could mean that the population status of these birds are not looking up.

Picidae (Family):

Other than the Banded Woodpecker (Picus miniaceus), this woodpecker (I am torn between the Laced Woodpecker, the Streak-breasted Woodpecker and the Streak-throated Woodpecker) is the first I have seen at Kent Ridge near my hall. But chances are that this might be a Laced Woodpecker (Picus vittatus) since in an observation, some had been observed in the vicinity of Kent Ridge Park, but then again that was back in 1998. Actually, I have seen another woodpecker but then the pictures were just a blot of blur movements that direct identification from them would drive an ornithologist cuckoo. =)

Pycnonotidae (Family):

And just in case you might have wondered what birds do when it’s raining cats and dogs, this is an example what happens. Compared to its sunny-day slim physique, the drenched Yellow-vented Bulbul (Pycnonotus goiavier) seemed to have put on more weight! By the way, the Yellow-vented Bulbul is called so because its vent (or butt) is a distinctive yellow hue(left).

Kawaii (or adorable) as it might seem at the moment, the Yellow-vented Bulbul (Pycnonotus goiavier) becomes more ball-like as the feathers are puffed-up to keep the little fella warm. While watching it trying to keep out of the rain (though failing rather miserably), I noticed that the Yellow-vented flew back and forth for a 2-3 times back and forth another tree. Not sure about the reason though..

Here’s a video of the Yellow-vented Bulbul (Pycnonotus goiavier) and its calls during that faithful day. Unlike the nasal quality of the Long-tailed Parakeets, the calls of the yellow-vented is a rapid, bubbling chic-chic-chic… and sharp harsh chwich-chwich.    

Oriolini (Tribe):

Though Oriolus chinensis (above) would win hands down in terms of sporting a bright, yellow coat, it’s common name is the Black-naped Oriole. Of course,  in its juvenile state, the back of its head (or nape) is still a sulphuric yellow. Talk about being misleading. :) Anyway, this was another bird that kicked me into a frenzy. I still remembered catching sight of it initially at the top of the Macarthur Palm’s (read as Mac-Arthur) as it was in the process of picking and swallowing the ripe fruits.

Skittish by a sudden human presence, it immediately flew down to a drain below. By this time, I was tingling with excitement as I was pretty certain I have never seen the likes of this bird in my life (the truth wasn’t revealed till I showed the picture to LK). By then I was straining to either stay in the spot to observe the bird or go back into my friend’s room and grab my camera, I decided on the latter whilst cursing (blast it, of all times my camera wasn’t there when I needed it) and hoping fervently it stay puts till I return.

And thank goodness, when I returned it was hopping by the drain before I caught a glimpse of it flying to the staircase at the end of the block. Stalking it, I went 3 floors down before I was approximately 50cm away from it. But just as I was ready to capture a shot of it drinking water, my battery decided to breathe its last breath. Internally I was cringing and going “Arggggghhhh!!!! Bloody hell, of all times, why, WHY?!!” Berating myself for my negligence, I ran all the way back to one end and then back again to see that (thankfully) the bird was perched atop another palm. And with the the batteries’ juice running to the fullest, my eyes and my lenses never left the oriole.

 
Splendid in manoeuvre, the Black-naped Oriole sweeps and circles to pick the fruits in style.

 
Caught in the act! One of my favourite pictures of the Black-naped Oriole during its feeding session. As if it knew that it had me entranced, it turned back and continued to pick the fruits while perching nonchalantly on the stem.

 
Shrouded in a juicy trove of glowing citrine and shimmering green tourmaline, the Black-naped feasted till its little heart’s content before taking off towards the evening skies.

Sturnini (Tribe):

And last but not least, the bird that I have been raving about since the beginning - Hill Myna (Gracula religiosa). From the picture on the left, you can see that its nape and the feathers covering its ears are a bright mango yellow while the right snapshot shows a decent shot of its deep orange bill (albeit small).

 
From where I was standing, I would have not noticed 2 blotches of black amongst the dark, verdant foliage of the towering tree beside King Edward 7 Hall if not loud, piercing ti-ung that reverberated through the cool evening air.

It regularly perches in exposed tops of tall trees but I seriously hope this would not be the first and last time I see it. Next on my agenda would be to catch a crystal-clear shot of this avian. Yeah, it’s either I sprout wings… or churn up a DSLR with zoom lens, so unless I have latent powers of Angel, the latter it is then! Matte ne!

Reference:
1. http://www.avianweb.com/longtailedparakeets.html

024. Pulau Sekudu Mini Series (End) – Don’t even be thinking of chilli crabs…

… if you value your fingers! But then again, not all the crabs that you see below aren’t suitable to be sold on the shiny silver platters for your 8-meal course. Those that come from mangrove areas are usually the ones caught, though the blue swimmer crab has been eaten as such delicacy.

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(Left): Thunder Crab (Myomenippe hardwickii) – so called because of the belief that only by the clap of a thunder, the crab will free you from its pinch – that is if your fingers get in between its pincers in the first place. It’s pretty common but prefer the shelter under rocks. At low tide, it will either crawl into a burrow or peer its way out from beneath a rock. With green eyes rimmed a crimson red, it hunts for clams and snails during the high tide before rendering them to tasty chow with its large, powerful pincers. What’s terrifying to the molluscs is nothing but delicious cuisine for us humans. We eat them – with the pincers particularly favoured!

(Right): Spoon-pincer crab (Leptodius sp.), with its spoon-tipped pincers (not obvious in the picture) are commonly seen on the shores and islands southern of Singapore, whether it’s amongst coral rubble or near the living reefs. Instead of sharp, pointy tips, the black pincers have white, spoon-shaped tips, which are presumably used to scrape off their meal (algae and detritus) encrusted on rocks. Imagine trying to eat pudding with chopsticks in place of the usual dessert spoon. =)

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(Left): Here we have a Sponge crab (Family Dromiidae) that’s on a sponge – an upside-down position compared to its usual form. Using its pincers, the Sponge crab will snip out a bit of a living sponge (sometimes ascidians) that’s just right for its body. Then using its last pair of slender legs that’s bent over its back, it holds the sponge atop – with a firmer grip provided by the leg’s sharp, little claws. As the living sponge continues to grow, the crab will continue to trim it to a suitable size. So unless it moves (and slowly too!), it really takes a trained eye to spot this well-camouflaged decapod. Besides providing an invisibility cloak of sorts, the sponge is also a good deterrent for potential sponge crab diners. Taking a bite of the crab (or the sponge in this case) will usually make the predator swear off sponge crabs – unless desperation takes the upper hand. :)

(Right): Flower crab (Portunus pelagicus) – all-time favourite seafood (or just one of them anyway) is another common crab, but difficult to spot as you can see (from the picture) that it tends to bury itself beneath sand and mud.

Males (like this one) are more beautifully-patterned and usually have bright blue legs and claws. On the other hand, females tend to sport colours like dull green and brown. Also, the boys have longer pincers – twice or three times longer than the width of their body. While the males possess a more pointed triangular shaped abdomen, the females are broader as it’s used to carry eggs.

Being a predator, the pincers are armed with sharp spines to snag swimming creatures. Never mind that the prey are motile and quicksilver in water, this crab that’s fully aquatic in nature is just as limber. Reason being that its last pair of legs are paddle-shaped and can rotate like propellers. And that’s why the Flower crab is also known as the Swimming crab.

In a pose that seems to say “Hug me!”, this body of the bulky-built Thunder Crab’s (Myomenippe hardwickii) was found amongst a bed of lush seaweed, an appropriate final resting place – till the tide washes in, that is.

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What looked like it might have been a young Spider conch (Lambis lambis) is actually a different mollusc altogether. It’s thought to be the juvenile of the Lambis lambis (Class Gastropoda)because it lacked the spines of the a typical adult conch.

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(Left): Another gastropod that we bumped into besides the supposed Spider Conch is the Blue-spotted nudibranch (Dendrodoris denisoni). But unlike the usual gastropods, nudibranchs lack the external protective shell common to snails and slugs. But compared to most nudibranchs (from the Greek “naked gills”), the Blue-spotted lacks the special set of minute jagged teeth (radula) that acts like a saw for breaking up food in typical sponge-eating nudibranchs. Instead, it releases digestive liquid, dissolves the sponge to soup-like texture before sucking it all up.

(Right): Another gastropod found was this small, air-breathing onchs (Family Onchididae). Onchs, unlike nudibranchs, have simple lungs or modified gills, allowing them to survive on terra. Sea slugs like the nudibranchs are limited to aquatic environment as they respire via gills. At high tide, they crawl away from their favourite spot on the rocks at shore to burrow into sand and mud; breathing from the air bubble trapped under the folds of their mantle. As the tide ebbs, these shell-less creatures crawl back onto the rocks and start grazing off the algae and lichen. To reduce water loss when out in the sun, they rely on their tough skin to do the work.

And my first time seeing an octopus, alive and kicking, on the shores of Singapore! Other times were limited to either a glimpse of one of its limbs or a dead body lying limply on a sun-baked shore. Octopi are also molluscs (or soft-bodied creatures) (Family Cephalopoda). Though these intelligent creatures have no internal nor external skeleton, they have a beak (similar to a parrot’s beak) held at its mouth to kill and decimate prey. It’s also used crack shells and inject poisons and digestive fluids into shellfish and other prey. Each of its arms have double rows of suction cups, each of which consist of ‘taste sensors’ to identify food.

Though they have good eyesight, octopi are deaf (not that it will be useful underwater or above it). Here are some of the ways which octopi use for locomotion purposes. There’s the slow crawling method, followed by ‘walking’ (2 alternating arms behave in a rolling gait while the remaining arms are utilized for camouflage). Then, there’s the usual swimming motion and the faster jet-propulsion technique. And last but not least, octopi have been known to also ‘fly’. I kid you not. Though not a usual travelling method, octopi have been observed to blast themselves out of water completely to escape predators [3]! How cool is that. :)

To my delight, another gem which Pulau Sekudu yielded was the gorgeous Blue Dragon (Pteraeolidia ianthina). Another first! An aeolid nudibranch, the Blue dragon has evolved a method of capturing and ‘farming’ its own fresh batch of zooxanthellae (golden-brown algae), which proliferate and convert the sun’s energy into sugars before passing a portion to the nudibranch [1]. An aeolid nudibranch is a type of nudibranch in which the mantle is extended into long finger-like projections (ceratas), rather than a feather-like external gill on the dorsal (or top) surface.

Also, aeolid nudibranchs have developed an amazing strategy to protect themselves from predators. They extract nematocysts from the coelenterates (comb jellies etc) on which they feed and store them in the special sacs at the tips of their ceratas. The nematocysts are used by coelenterates as stinging weapons to catch food and for defence. Aeolids ‘steal’ these weapons and discharge them when needed in their own defence [4].

Some other creatures which can rival the beauty of the nudibranchs are marine flatworms (Family Pseudocerotidae) such as the one above. Okay, so this example might not be a jaw-dropping beauty, but it does come from a family which consists of bella donnas like these. Unsegmented, flatworms are extremely flat (usually less than 1mm thick). Of course being flat, respiration is a cinch as oxygen can diffuse easily from any part of its body. Nutrients can also diffuse rapidly from the central gut to the entire body.

Marine flatworms are hermaphrodites, that is they both possess male and female reproductive organs. In some cases when two flatworms meet, they exchange sperm by simply insert their needle-like penis anywhere in the body of the partner. But in other species, each flatworm refuses to be the ‘girl’ and tries to impregnate the other without getting impregnated as producing eggs require more energy. In short, they need to eat more! This results in a bout of 'penis-fencing' when such flatworms meet! I have yet to come across such an interesting display but one can only hope. =)

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And speaking of eggs, the white casings in the left picture belong to the Spiral melongena (Pugilina cochlidium) while on the right are eggs bore by the squid.

All in all, it was once again a smashing trip down the Southern shores of Singapore. A big thanks to Ron and LK also for providing me an eye-opening opportunity like this. My gratitude to Ron, July and KS also for their blog entries as all three provided some information pertaining to the identification of the critters above (and the 3 entries before). :)

References:
1. http://www.seaslugforum.net/factsheet.cfm?base=pteriant

2. http://www.wildsingapore.com/chekjawa/text/c311.htm

3. http://www.octopus.com/

4. http://www.sergeyphoto.com/underwater/nudibranchs.html