Pulau Semakau

The day started really early at 3+ in the morning when most of us woke up to get ready for our first ever marine biology field trip to Pulau Semakau. Reaching school before 4.30am, all of us were really excited while waiting for the bus to come and bring us to the pier. Finally the bus came and our journey there was actually pretty noisy with all the excitement.

The weather was quite windy and it was drizzling as well. Being at the pier, the winds were super chilly and cold, with droplets of water splashing on us. Our guide, Mindy brought us to a corner to seek for some shelter while waiting for our boat to arrive. She gave us a brief introduction about herself as well as the landfill island we were about to go to, and also gave us group badges. We were called the 'Sotongs'!

The boat ride was initially very shaky. The currents and winds were rather strong. It was also Ali's first boat ride, which made him quite sea-sick. However, the 5 of us, with some other friends chatted throughout the journey there, which honestly actually prevented some of us from puking all over the place.

Reached the island at around 7.10am? The sun was already rising and we had to walk 2km on the road to get to the entrance of the mangrove leading towards the intertidal area and hence these photos :D These are just a small fraction of the photos though~ haha

Reached the entrance and we all changed to our booties (if we had them) and sprayed insect repellent everywhere....for mainly the girls. Since it was raining before we reached there, there was a tree that fell over and blocked the pathway so we had an obstacle! It was really muddy inside there and it was best to not stay put, since the countless thirsty mosquitoes there were attacking us every second. Some of the guys squished the mosquitoes when they were sucking their blood so the mosquitoes' blood were splattered all over their legs omg.

Reached the intertidal area!

Well what we did after reaching the intertidal area is I guess, pretty much self-explanatory haha we saw so many marine animals and snapped so many photos. Our guide also told us so much about them! The sun was really pretty too, with the nice sceneries :)) This was a first time experience for many of us going for an intertidal walk and the number of marine organisms we saw was overwhelming. This was nothing like going to the zoo or the birdpark as we were up close to the organisms so we could touch and feel them xD There were so many organisms we have never encountered in our lives before namely starfish, nudibranches, hermit  crabs, etc. It was genuinely an enriching and unique 1st time experience for the five of us students.

307! xD

Left the intertidal area and took a shuttle bus to the end of the island to know more about it's history. So many mosquitoes followed us in! We were like trying to kill all of them throughout the ride..

Group photo in the order of the rainbow! :D

After eating some snacks and resting, we went back to the place we all came from and explored the landfill, in the bus of course haaha we did get to sniff the air outside for a few seconds though!

Took the boat back to mainland and bus back to school, concluding the field trip! It was really really fun and enjoyable. It was a really great and interesting experience for us all, going to an island that Singapore owns early in the morning, wearing booties for the first time, seeing so many different marine animals for the first time and so much more!! We really liked this field trip and learnt so much from it. All of us were super tired after it though! Slept a lot after reaching home haha :D

In this field trip we really learnt so much about the island itself as well as Singapore. It's the only landfill island in the world and it belongs to Singapore. Without going there, we'd probably still think that it's a filthy island with all the waste there since it is after all, a landfill. It's really clean there and the weather's nice and cool. It's an island full of purpose and use. Honestly, some of us didn't even know the existence of this island or how it came about. I certainly did not know it existed and that it's actually a combination of more than one island, with artificial land. It's predicted to last until 2045. That's 33 years more. However, with the ever-growing population of Singapore, I doubt it can last that long. Singapore is really, really tiny and the population just keeps increasing.

We have learnt that organisms have interesting habits and modes of reproduction in the wild. Little did we know that hemaphroditism was so common in  the wild and there was such a bizarre reproduction technique called "penis fencing". Two organisms would fight with their penises and the loser whose penis drops off first would become the female and the victor would become the male. Obviously the organisms would want to win and become the male as it is less time and energy consuming. This reproduction trait really intrigued us.

We have also learnt that marine organisms thrive anywhere, not just in the deep blue sea. We thought that most marine organisms could only be found down in the depths of the ocean but we were so wrong. There was a great diversity of organisms in the shoreline too. And its the shoreline of a landfill! After this experience, we cant wait to visit other shorelines like Pulau Hantu and St John's especially, since it is a rocky shore so the diversity of organisms will be quite different from the sandy shorelines of Pulau Semakau and Pulau Hantu.

Desis martensi

Desis martensi (commonly known as Marine Spider)

Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Arachnida
Order:	Araneae
Suborder:	Araneomorphae
Superfamily:	Dictynoidea
Family: Genus:	Desidae Desis

Where seen?
This little spider is commonly seen on many of our shores: on rocky shores, coral rubble areas and reefs. It is more active at night.

Features:
Body to about 1cm. The spider has long furry legs. It is greyish sometimes with a pink tinge. At high tide, it hides in air pockets among crevices of submerged rocks. It emerges at low tide to hunt. It can 'walk' on water, scuttling rapidly over the water. Its hairy feet prevent it from breaking the water surface tension.

What does it eat?

These spiders have been seen with tiny crickets and little shrimps in their jaws.

Status and threats:

The Marine spider is listed as 'Vulnerable' on the Red List of threatened animals of Singapore.
According to the Singapore Red Data Book: "The type specimen was collected at the reefs fringing Sentosa. Loss of the natural intertidal zone in reefs and rocky shores would threaten its survival."

Credit: http://www.wildsingapore.com/wildfacts/arachnida/desis.htm

Macrophthalmus sp.

Macrophthalmus sp. (commonly known as Sentinel crab)

Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Infraorder:	Brachyura
Superfamily:	Ocypodoidea
Family: Genus:	Macrophthalmidae Macrophthalmus

Where seen?
This inconspicous little crab with eyes on super long stalks are sometimes seen on soft silty and muddy shores such as swimming lagoons. It builds distinctive holes which are either rectangular or oval and seldom circular.

Features:
Body width 0.5-1cm. Body is flattened, squarish or somewhat rectangular. The eye stalks are long and in some species can even extend outside the sides of the body. This feature probably gave them their common name. Both pincers of equal size.
Sometimes confused with fiddler crabs (Uca spp.). Sentinel crabs do not have one enlarged pincer like the fiddler crabs. Sentinel crabs are also not colourful, usually drab brown with darker mottling.

What does it eat?
It feeds on detritus and small worms.

Credit: http://www.wildsingapore.com/wildfacts/crustacea/crab/ocypodoidea/macrophthalmus.htm

Synaptid sea cucumbers

Synaptid sea cucumbers

Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Holothuroideaia
Subclass:	Apodacea
Order:	Apodida
Family:	Synaptidae Burmeister, 1837 [1]

Where seen?

These sea cucumbers appear to be seasonally abundant and are found on many of our shores. When in 'season', large numbers of small skinny ones (5-10cm long) may be seen draped around sponges and other encrusting animals. In the seagrass meadows, thicker very long ones (10-12cm, to 30cm long) are entwined among the seagrasses. They might even be seen crawling (slowly) on the sand.

Features:

Synaptids have a thin body wall and are more delicate than other sea cucumbers. Synaptid sea cucumbers don't have tube feet. Instead, they may stick to things with tiny hooked sclerites that poke out of their soft bodies. This is why they stick to our hands if we touch them. They have thin body walls and are fragile, so we should not handle them.

Credit: http://www.wildsingapore.com/wildfacts/echinodermata/holothuroidea/synaptid.htm

Stichodactyla gigantea

Stichodactyla gigantea (commonly known as Giant Carpet Anemone)

Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Anthozoa
Order:	Actiniaria
Family:	Stichodactylidae
Genus:	Stichodactyla
Species:	S. gigantea
Binomial name
Stichodactyla gigantea (Forskål, 1775)[1]

Where seen?

This enormous colourful carpet anemone with short skinny tentacles is commonly seen on our Southern shores, usually on hard surfaces such as coral rubble, near reefs. It is also sometimes seen on coral rubble on our Northern shores.

Features:

Those seen about 40-50cm in diameter when exposed out of water. The oral disk expands when submerged. The large oral disk covered with short tentacles so that it resembles a shaggy carpet. The oral disk is often folded and rarely held flat against the surface, unlike Merten's carpet anemone (Stichodactyla mertensii). The long body column is usually buried or inserted into a crevice and ends in a pedal disk that anchors the animal.

Body column is sometimes colourful (bright pink, orange, yellow). Bumps (verrucae) appear as rows of spots, generally in bright colours (pink, purple). They are non-adhesive and found on the upper part of the body column.

Tentacles short (about 1cm), narrow and uniform in length. Usually brown or purplish with lighter coloured tips. The tentacles are not very tightly packed and when submerged, are usually in constant motion. The tentacles are very sticky. It does not have a fringe of long-short tentacles at the edge of the oral disk like Haddon's carpet anemone (Stichodactyla haddoni).

Carpet food:

Carpet anemones harbour symbiotic single-celled algae (called zooxanthallae). The algae undergo photosynthesis to produce food from sunlight. The food produced is shared with the sea anemone, which in return provides the algae with shelter and minerals. The zooxanthallae are believed to give tentacles their brown or greenish tinge. Carpet anemones may also feed on fine particles that are trapped on their bodies. These anemones have not been observed to eat large animals.

Stinging carpet!

Like other sea anemones, the Carpet anemone has stingers in its tentacles. Generally, these stings do not hurt human beings, but they can leave welts on sensitive skin.

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

Alcyonacea

Order Alcyonacea (commonly known as Soft Corals)

Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Anthozoa
Subclass:	Octocorallia
Order:	Alcyonacea Lamouroux, 1812 [1]

Where seen?
Soft corals are commonly seen on many of our shores. Some resemble flowery bushes, others giant leathery disks. Yet others are tiny and overlooked. They are found growing on boulders and other hard surfaces, as well as among coral rubble and living hard corals on the reef flats.

Features:
Soft corals are colonies of tiny, individual polyps linked to one another. Soft corals can look like branching bushes or trees. They may also be flatter and look like mushrooms. When exposed at low tide, they often flop over and look like a pile of jelly or fried eggs! When submerged, however, they expand into beautiful plant-like forms and some appear 'furry' as the tiny polyps expand.
Soft coral polyps have 8 (or multiple of 8) tentacles that are pinnate (branched or feathery).

Soft support:
Although there are some exceptions, many soft corals don't produce a hard skeleton. Instead in colonial soft corals, the polyps are connected by a shared tissue.

Tiny spikes of calcium carbonate, called sclerites, are embedded in the tissue mass. These sclerites are used to identify soft coral species. In some, the sclerites are far apart resulting in a more floppy soft coral. In others, the sclerites are closer or fused together to form firmer support. The entire tissue mass is covered with a skin and the polyp tentacles emerge through this skin. In some soft corals, the skin can be quite tough and leathery looking, thus these are often called leathery soft corals. Out of water, soft corals may flop over and may look small. But underwater, they expand and spread out to maximise the feeding surface.

What do they eat?
Most soft corals feed on plankton, some also feed on finer particles. Like other cnidarians, soft coral polyps have tentacles with stingers to capture food.

Many soft corals harbour microscopic, single-celled symbiotic algae (zooxanthellae) within their bodies. The algae undergo photosynthesis to produce food from sunlight. The food produced is shared with the host, which in return provides the algae with shelter and minerals.

Role in the habitat:
Some soft corals are homes to tiny animals. Some tiny animals eat soft corals and look just like their much larger prey.

Coral babies:
Soft corals can reproduce asexually: budding of new polyps enlarges the colony. However, they also reproduce sexually. The polyps may produce sperm or eggs. The eggs develop into free-swimming larvae that drift with the plankton before settling down to start a new colonies.

Credit: http://www.wildsingapore.com/wildfacts/cnidaria/coralsoft/coralsoft.htm

Pilumnus vespertilio

Pilumnus vespertilio (commonly known as Hairy Crabs)

Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Infraorder:	Brachyura
Section:	Eubrachyura
Subsection:	Heterotremata
Superfamily: Genus:	Pilumnoidae Samouelle, 1819 Pilumnus

Where seen?

Hairy crabs are commonly seen on rocky and coral rubble areas on many of our shores. The "teddy-bear" of crabs, these hairy little creatures fluff up in the water and look positively cuddlesome. But they are hard to spot and usually well hidden, especially during the day. They are more active at night, but even then, they usually scuttle into the nearest crack or crevice at the first sign of danger.
These little crabs are not the same as the large 'Hairy crabs' that are served in our restaurants as seafood.

Features:

Body width 3-5cm. As its name suggests, the hairy crab is indeed quite hairy. Its body and limbs are covered with long, silky hairs. These trap sediments allowing the crab to blend perfectly with its surroundings. In the water, its hairs 'fluff up' breaking up its body outline. It also moves slowly and thus overlooked as some bit of drifting rubbish. It has large claws, some with thick black fingers.

What do they eat?

The Common hairy crab eats mainly seaweed. It may also eat toxic zoanthids (colonial anemones) and this makes the crab mildly poisonous. Various hairy crabs on our shores have been observed nibbling on hard seaweeds, sponges and even appearing to snack on bristleworms and possibly having a taste of a nudibranch.

Status and threats:

Several of our hairy crabs are listed among the threatened animals of Singapore. Like other creatures of the intertidal zone, they are affected by human activities such as reclamation and pollution. Trampling by careless visitors also have an impact on local populations.

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