1st Hunting-Seeking - Knobblies Galore!

My first hunting-seeking survey in 2010 was a splendid one with lots of Knobbly Sea Star appearances (for once!). After the past few lonesome hunting-seeking surveys, I grew not to take any partners for granted! This time round, I teamed up with a great partner and thanks to her, the survey was quite smooth sailing.

We spotted quite a few crabs, and heres a juvenile Swimming Crab (Thalamita sp.)Flower Crab (Portunus pelagicus. Swimming crabs are easily identified from their last pair of legs that are paddle-liked, while the rest of its legs are pointed, which enables it to swim very well. Their speed and agility, coupled with their long pincer, helps it to catch fish and other fast moving prey.

It seems that we have 'invaded the privacy' of these 2 Dog Whelks (Nassarius pullus). One was intially on top of the other, but soon both went on their separate ways after we stared at it for some seconds. These snails have long siphons which they use to detect dead matter. Without these important scavengers, dead animals will not be dispose off quickly, and their rotten body will pollute the environement, eventually affecting us.

We saw a number of Sandfish Sea Cucumbers (Holothuria scabra), albeit in different habitats. This sea cucumber is the species that some human beings deem as a delicacy. However, they must be processed first as it is mildly poisonous. Often burrowing in sand (and thus its name), it uses its tube feet to cling onto surfaces. Unlike us, sea cucumbers circulates water through its body to transfer nutrients and can get very stressed out when they are out of water. Thus, we should always leave these animals in their natural habitat, or if we really have to, not remove them from water for too long.

An Orange Fan Worm, which probably got its name from its feather-like tentacles, was also recorded. We always take extra care by approaching this segmented worm slowly as it is very sensitive to movements, and retreats into its home (a flexible tube) in lightning speed once they sense danger. A role model of the 3Rs (reuse, reduce, recycle), the Fan Worm personalises its home by building it with sand and its own mucus. A very green and inexpensive way, isnt it? Apart from its purpose as a hiding place, the tube also keeps the worm moist if they are exposed at low tide.

Perhaps starting the trend of using black coloured lipstick, Black Lipped Conch (Strombus urceus) almost escaped my not-so-keen eyes due to its excellent camouflaging, with algae & particles covering its shell. Like other conches, it has a strong operculum that helps it skip around.

A few Gigantic Anemone (Stichodactyla gigantea) were also spotted. With sticky and stinging tentacles, Anemones trap and entangle animals that carelessly bump into them. While the toxin from the stingers generally affects smaller animals, it may leave welts on sensitive skin, so, better not touch them! In one of the anemones, a clownfish was darting around underneath it. Clownfish has a layer of mucus over its body which protects it from the stinging tentacles and thus enjoys a cordial symbiotic relationship with the Anemone. The clownfish gets shelter from the anemone, and in turn protects it from predators.

I chanced upon a pair of twins and decided to take their portrait even though we were not required to record Corals. The Sunflower Mushroom Coral (Heliofungia actiniformis) is often mistaken with the Anemone due to its long tentacles. It has a stalk when it is juvenile, resembling that of a mushroom, thus its name. As it grows older, this stalk breaks off, and they end up free living (长大了, 翅膀硬了,会'走'了). This hard coral is like a bungalow as it is a single polyp/ animal, unlike other hard corals which are like HDB/ Condo as they contain many polyps living together.

We saw 2 Polka Dot Nudibranchs (Jorunna funebris) side by side, looking quite jovial and carefree. Nudibranch, translated in latin, means 'naked gills' and refers to the exposed feather-like rhinophores on its back. A type of sea slug, Nudibranchs are born with shells but loses them as they become adults. Thus, to replace the protective shell, species like the Polka Dot Nudibranch acquire poisons from the blue sponge it feeds on; others develop bad tasting glands to repel predators. Most of the nudibranches are clad in bright colours to warn predators of its poisonous or bad tasting nature.

Good things seem to come in pairs. Near the reef edge, 2 Red Swimming Crabs (Thalamita spinimana) were motionless amongst the coral, quite unlike its usual agile self when it senses movement/ danger. One of them was feeding on what looks like a prawn for dinner, perhaps too contented to notice our presence.

I was hoping to show my partner the Octopus (Order Octopoda) as its her first time exploring the shores of Semakau. This kind fellow seem to have heard my wish, and appeared right in front of me. One of the smartest invertebrate, Octopuses are known to be capable of learning and is able to remember its tracks and even open jars. Without a skeleton, it is more flexible than an olympic gymnast and can move into the tiniest crevices. A fierce predator, it uses its tentacles with powerful suckers to catch its prey, before paralysing the prey with a bite. With special cells, the Octopus can change its colour instantly for the best camouflage.

On our way back, a Blue bordered flatworm ,seeking refuge on a blade of seagrass, caught my attention. Apparent from its name, Flatworms are very flat and can hide into any crevices. Being very flat, it does not have a respiratory or circulation system. Instead, oxygen diffuses through its body. Another fierce predator although of small animals, it kills by injecting digestive juices into the prey and sucked up the end product of a liquified meal.

I wonder whether it is my partner whom brought me the luck, we recorded a total of 18 Knobbly Sea Stars (Protoreaster nodosus)! Drawing its name from the knobs on its body, this is one of the largest Sea Star on our shores. Unfortunately, due to overcollection in the aquarium trade and rapid destruction of habitat, the Knobbly Sea Star is a threatened species in local waters. It is heartening to see so many of them, which proves that our shores are healthy enough as a place for them to identify as home.

A treat to the stunning scenary of Semakau usually awaits us at the end of evening surveys. The peaceful and serene shoreline is a good reminder of the purpose of our continuous effort in Project Semakau. Hopefully, it will all pay off and this piece of land that is rich with biodiversity will be conserve, and not end up like....

this contrasting island by its side.....