Monday, November 29, 2010

Story of Liana


Lianas are woody climbers. They are often known as the 'highway' of the forest. The leaves of the liana are found near the top of the canopy to absorb as much sunlight as possible for photosynthesis. The liana then spreads along a few trees as it grows. This forms the 'highway' at the canopy of the forest, thus the animals like squirrels do not need to climb up and down the trees to get from one tree top to another. If one of the trees twined by the liana is to fall in the forest, it will bring down the other trees too. This allows the pioneer species to grow when there is a sudden gap in the canopy.

Story of Fig Tree and Fig Wasp


This is a White leaf fig (Ficus grossularioides).

Although fig trees are called 无花果 in chinese, (literally means no flower fruit), they do have flowers that are enclosed in the fig.

All figs have 4 prominent features.
1. Sap.
2. Prominent bud.
3. Triangular vein on the underside of the leaf.
4. Scars on the stem of the plant.

Fig trees have a symbiotic relationship with the fig wasps. Fig wasps are the only pollinators of the fig trees. The female fig wasp will drill its way through the fig, passing through the mouth of the fig which is covered with male flowers. Then, she will deposit her eggs in the cavity which is covered with female flowers. While depositing her eggs, she will also deposit some of the pollen that she was carrying. This helps to fertilize the flowers in the figs. However, as the hole is very small, the female wasp will usually lose its wings and die inside the fig after laying her eggs.

As the fig develops, the wasp eggs hatch and develop into larvae. After going through the pupal stage, the mature male will mate with a female, then it will dig its way out of the fig, creating a tunnel for the females to go through. The males usually sacrifice themselves and distract the preys around the figs to ensure that the females can continue the life cycle successfully.

Sunday, November 21, 2010

Story of Macaranga

Haven't blog for a long time! Since exams are over and I promised someone that i'll blog, so here I am. Haha. I've been tasked to tell the 'story' of Macaranga... so here it is!

The Macaranga is also known as the Common Mahang, which has a symbiotic relationship with the ants. The ants will protect the plant by gnawing off any climbers that tries to climb onto the plant.

In return, the plant has stipules (black ring) that supplies the ants with food (lipids). It has hollow stems which serves as nesting place for ants, and also allow the ants to move freely inside the plant, and small holes on the stems to allow ants to move in and out of the plant.

Sunday, August 29, 2010

Semakau Walk on 28 Aug

Haven't blog for a long time! Am quite busy with school etc. Hopefullyyyyy i'll get more time to blog about all the places that i went after this semester ends :D

Anyway, finally went to Semakau today again! :D But instead of guiding, i went as a participant with NUS High to listen to other people guide :D haha. My group was the Seagrass group! (: And our guide today was mindy!

As usual, as it was a morning walk, we had to walk to the intertidal area. The weather today was great! It was quite windy and cooling and i think everyone enjoyed the walk to the forest (:

The best reward from morning walks is the beautiful sunrise (:

Saw this plant beside the road along the rock barn. Never noticed it during the previous trips. Did it just grew recently? Or was i not observant enough? haha. Not sure what this plant is though.

We walked through a patch of secondary forest and reached the intertidal area. To get rid of the irritating mosquitoes, we headed out for the mangroves first.

Here's mindy telling the group about the mangroves! As these plants live under harsh conditions, they have several adaptations which enable them to survive better. For example, the Rhizophora species have prop roots which helps them to stabilize themselves on the soft ground. They also have waxy leaves to reduce water loss due to the high salinity level and the high amounts of sea spray that they get.

And of course, they have special adaptations for reproduction too. Instead of just letting their seeds germinate themselves in the harsh conditions, the seedlings, called propagules, are germinated on the parent tree. When it is more matured and ready to face the real challenge, it will drop down from the parent tree and get carried away by the current, and hopefully it will land somewhere suitable for growing.

When we look down at the mudflat, we often see trails created by these Creeper Snails. The longer the trails, the longer the tide has been out.

As we walked along the side of the forest, we saw this Sea Lime (Ximenia americana). Unfortunately, it wasn't flowering nor fruiting. During the one of the previous trips, i tried eating the fruits of the Mangrove Lime for the first time, and it tasted quite nice! :D

Next, we saw a Sea Hibuscus (Talipariti tiliaceus). This is also a coastal plant, with distinctive heart-shaped leaves. The yellow flower will open in the morning, and as the day gradually passes, the colour of the flower changes to pink, and then wither and dries up when the sun goes down.

On the same plant, there were quite a few juvenile Cotton Stainer Bugs (Dysdercus sp.). Interestingly, these Cotton Stainer Bugs feed on the seeds of this plant and are not able to survive on other plants.

As we headed out, we walked past another mangrove plant (Avicennia alba), which has pencil roots instead of prop roots like the Rhizophora species.

On the rocks, there were many Oysters (Family Ostreidae) growing.Oysters are sessile animals usually encrusted on rocky surfaces and filter feeds to get food from the surrounding water. During low tide, it will close up its shell to prevent water loss and protect itself from its predators.

Near the roots of a Bakau Tree, there were many Fiddler Crabs (Uca annulipes) scrambling around. The ones with a big claw are the male Fiddler Crabs. The big claw helps to attract the attention of the females and ''tells'' the females that 'LOOK! I have a big claw = I very powerful = I can protect you'. So, the bigger the claw, the sexier it is. However, it also handicaps the males as it cannot use the gigantic claw to feed itself and also makes itself more visible to the predators.

In the pools of water, we saw this Blue Striped Hermit Crab (Clibanarius longitarsus) in a telescopium shell! As hermit crabs are not true crabs, they have a soft abdomen which requires them to have extra protection. As the hermit crabs grow bigger, they will need to seek for a bigger shell to stay in. However, if it can't find a larger shell, instead of growing bigger, the hermit crab will shrink! :O Hence, it is important that we should not pick up shells whenever we visit the beach. Quoting Mindy, some people may have the mentality that it's okay to just bring home ONE shell because it is just ONE shell. Imagine everyone in Singapore has the same kind of mindset, then 4 million shells will be gone! And the poor hermit crabs will shrink, or have to walk around the shores naked.. ):

On almost every trip to Semakau, this is quite a common sight. Although this may look like some defecate of some sort of animals, it is actually an Acorn Worm (Family Enteropneusta) cast! The worm is buried underneath the sand, and as it moves deeper into the sand, it swallows the sand and process them, then passing the processed sand out from the other end of its body, to the surface thus forming the cast.

Here's a picture of the Victoria boys near the Seagrass meadow.

And our dearest Hunter-Seekers at work! (:

One of the girls in my group spotted this in one of the pools of water. I thought it was quite cool as it resembles a hand showing 4 fingers, which reminded me of the 4 points that all the guides will stress on before we go for an intertidal walk.
1. Always walk behind the guide as the guide will know which is the safest and best route to walk.
2. Always walk in a single file to minimize the damage done to the living things in the area.
3. Never touch things unless the guide says so, as there are many animals like the anemones with stinging tentacles and may sting quite badly when you touch them.
4. Never remove your shoes at any time during the walk as it is very dangerous to walk barefooted on the shores.

Back to the organisms, this was the first pair of Sand-sifting Sea Stars (Archaster typicus) in the pseudo-copulation position. It is said that these sea stars staying in this position for 3 months before they release their eggs and sperms into the surrounding water will help to increase the chance of external fertilization. It is great to see these sea stars reproducing! (:

As we walked on, we were greeted by a Sponge invasion. Sponges are very simple animals that comes in many different kinds of colours, shapes and sizes. Sponges in real life do not look like SpongeBob at all. In fact, i've never seen a square Sponge before! Hahaha.

The hunter seekers found us a Synaptid Sea Cucumber (Family Synaptidae). Sea Cucumbers have oral tentacles that they will extend to grab food particles into its mouth when it is submerged in water. As this species of Sea Cucumber has very thin walls, we should not touch them as they may be stressed up and disintegrate!

At the same area, we saw not one, but TWO! Dragonfish Sea Cucumber (Stichopus horrens). Unlike us, Sea Cucumbers are invertebrates, thus, when they are out of water, it may look like it's 'melted'. This also enables them to camouflage better in its surroundings.

Then, we headed for the Death Zone! If you look closely, you'll see a walking trail amongst the Seagrass. The Death Zone was formed after numerous trips. To minimize the damage done to the Seagrass meadow, we will always stick to one path, thus stressing the importance of walking in a single file.

At the side of the trail, i saw this very beautiful Stonefish Sea Cucumber (Actinopyga lecanora).

When we reached the sandy area, we saw this Cushion Star (Culcita novaeguineae). Just like other Echinoderms, including sea cucumbers, they have a penta-radial symmetry which can be seen clearly with the 5 rows of tube feet.

We also saw this Sandfish Sea Cucumber (Holothuria scabra). This is the species that we usually eat in the Chinese restaurants. However, it needs to be properly processed before it is edible.

Amongst the Seagrass, we saw this Gigantic Anemone (Stichodactyla gigantea). This is one animal that we shouldn't touch as these anemones have stinging cells in their tentacles that may sting your fingers if you touch them.

As we moved on, we saw this ultra long drift net just beside the seagrass. It feels very depressing to see drift nets on our shores as it causes detrimental effects to the animals like fishes and crabs. 

Many fishes were found trapped and dead in these nets..

The possession of these drift nets is actually illegal in Singapore. Despite many drift nets found and many innocent animals killed, the authorities don't seem to be doing anything about it. Hopefully the drift nets will be removed soon so that animals will not be killed by it anymore.

Moving on, we saw two Noble Volutes (Cymbiola nobilis).  Although they have very pretty shells, they are actually very fierce predators that can wrap their muscular foot around their preys to suffocate them!

Beside the Noble Volutes, we saw this Sand Collar. It is the eggs of the Moon Snails. When the eggs hatch into little Moon Snails, the Sand Collar disintegrates and disappears. Signs of reproduction tells us that the animals are doing well! (:

This looks like a.. hybrid? Haha it doesn't look like the normal Knobbly Sea Stars that we usually see.

The Knobbly Sea Stars (Protoreaster nodosus) are the iconic animals of Semakau. On every visit, I'll hope to see some of the knobblies to make my day. Just learnt from a shrimp expert that some tiny tiny shrimps may live on the knobblies! Shall try to look out for them next time.

We also saw a dead Scallop (Comptopallium radula). The Scallop has a special way of moving which i think is quite cute :D As they are bivalves, they have a two-part shell and to move, they will flap their shells and eject water from their mantle cavity.

As we moved further out, we saw another Stonefish Sea Cucumber (Actinopyga lecanora)..

and 2 more Cushion Stars (Culcita novaeguineae)! Happy to see the yellow one again :D it seems to be doing well and growing bigger everytime we see it! (:

It seems to be a Echinoderms day as we saw 4 different kinds of Sea Cucumbers and 3 different kinds of Sea Stars! (: A group shot of the juniors with our awesome guide :D Hope everyone enjoyed themselves today, and jiayou to the juniors who are supposed to complete their assignment! :P

Sunday, June 6, 2010

Sisters Island Walk on 30 May

We went to Sisters Island for a guided walk last Sunday. It was my first time there and I was glad that I wasn't guiding so that i could have more time to look at the animals there.

Morning trips are always great as we're greeted with the sunrise when we reached the islands.

Just when we entered the lagoon, we turned around and saw this flowering Tembusu Tree (Fagraea fragrans). The flowers give off a fragrant smell. This tree is featured at the back of our $5 note!

On the rocky shore, there were a lot of Barnacles (Class Cirripedia) growing on the rocks. The baby Barnacles are actually like little shrimps and swim freely. When they are more matured, they will glue themselves head down to a hard substrate like a wall or rock and develop a shell around it.

Marcus found this Wandering Cowrie (Cypraea errones) amongst the rocks. Cowries have a beautiful smooth shell as when it is submerged in water, its mantle will usually wrap around its shell and prevent it from abrasion.

The hunter seekers found us 3 Feather Stars (Class Crinoidea)! I thought the green one was rather special as I haven't seen a green one before that. They have arms that are in multiples of 5! However, their arms are very fragile, thus we should not touch them.

As we ventured out, we saw Sea Grapes (Family Caulerpaceae) growing on the rocks too! Some species of Sea Grapes are actually edible and people consume them fresh as salad at some parts of the world.

And here's the small small flatworm (Pseudoceros sp.). It took it a while to relax itself before posing nicely for me to take a picture of it :D

While walking, Yingwei found this Giant Top Shell (Trochus niloticus) between the rocks!

The hunter seekers also found this tiny Brittle Star (Subclass Ophiuroidea). It has very thin and flexible arms. As its name suggests, its arms are also very brittle, thus we shouldn't touch it when we see one.

While walking, we also saw a few Soft Corals that were bleached! Corals are bleached when the symbiotic algae living in them, called the zooxanthellae leaves the coral polyps, probably because the corals are experiencing stress. Other than Sisters Island, Corals on other Southern islands like Semakau were also beached!

Here's a hard coral. Hopefully the corals will recover soon and not continue bleaching! Can't imagine what our reefs will be like without these corals..

I think it is my first time seeing a Leaf Slug (Elysia ornata). These slugs feed on the sap of the algae and are able to retain the chloroplasts from the algae in its body, thus giving it its body colour. Under sunlight, the chloroplasts in the slug's body can photosynthesize and provide nutrients for the slug.

We also saw this SUPER LONG Striped Ribbon Worm (Baseodiscus quinquelineatus). It is probably at least 40 to 50 cm long. It can grow up to more than 1m long!

Here's Marcus talking to his participants about the animals living near the rocky shores?

And when we took a closer look, we saw many Limpets (Class Gastropoda) on the rocks! Unlike the Barnacles that glue itself to the rocks, Limpets can move around. However, its foot grips tightly to the rock so that it won't be swept away by the currents or waves.

I saw a Branched Tentacled Anemone (Phymanthus sp.) near the rocks. Like other anemones, this one has tentacles that can sting too!

Quite happy to see a Red Egg Crab (Atergatis integerrimus) as I haven't seen it for quite a while already. The bright coloured body seems to serve as a warning to others to tell them that it is actually poisonous so we shouldn't eat it.

Not far away, we also found a relative of the Red Egg Crab, which is the Brown Egg Crab (Atergatis floridus). It's brownish body helps it to camouflage itself amongst the rocks so that it will not be spotted by its predators easily.

Octopuses (Order Octopoda) are considered as the smartest invertebrates. They have very good eyesight and also a well-developed brain which allows them to learn things in a fast pace as compared to other animals. It is also able to change its body colour to camouflage better in its surroundings.

 Next, we saw a Phyllid Nudibranch (Phyllidiella pustulosa) with a Tidal Hermit Crab (Diogenes sp.). The Phyllid Nudibranchs usually has a black body with bright colourful patterns on its body. The bright patterns on its body may serve as a warning to its predators to tell them that it is actually very toxic. They are able to secrete toxins that can kill an entire fish tank when they're stressed!

There were also a few Gigantic Anemone (Stichodactyla gigantea) around.

There's also a Moon Snail (Polinices sp.). It may look very elegant but it is actually a very fierce predator! It can wrap its muscular body around its prey like bivalves, and suffocates it. Then, it secretes an acid which can its prey's shell and creates a hole in the shell using its radula.

This is a Black Sea Cucumber (Holothuria leucospilota). Different species of Sea Cucumbers have different types of defense mechanisms. For this species, it is able to eject sticky white threads from its anus when disturbed, and the threads can sometimes entangle the disturber.

A common sight at most of our Southern shores - the Polka Dot Nudibranch (Jorunna funebris). Nudibranch means naked gills in Latin, hence as its name suggests, the feathery naked gills of this Nudibranch can be seen on its back. It also has a pair of rhinophores on its head which helps it to sense its surroundings.

The second Nudibranch of the day - Discodoris boholiensis. This species of Nudibranch is often confused with the Flatworm (below) as their colours may look similar.

However, this Flatworm (Acanthozoon sp.) is much flatter, and does not have naked gills on its body. Instead, the Flatworm breathes through diffusion. As it is very very flat, oxygen diffuses easily into the different parts of its body. Being flat also allows it to go through crevices between rocks to feed on its prey.

Towards the end of the walk, dark clouds suddenly covered the sky and strong wind started to blow as the tide came in really fast.

And here's Sofina trying not to get blown away by the strong wind :P

But after a while, the sky cleared and a rainbow appeared! Many of us were taking pictures of the rainbow. I'm starting to get obsessed with rainbows! Haha. It was a great day and hope everyone enjoyed it (: