Sunday, February 24, 2008

Semakau Inter-Tidal Walk on 23 Feb 2008

Forty Ninth Discovery Posting:

A familiar sight at a familiar place (picture below).
This is Semakau (picture above). Singapore's first offshore land fill and now the last land fill. And on the shores of this island is where RMBR with its volunteers conduct guided Inter-Tidal walks.

Just yesterday, I was out on Semakau for the first guided Inter-Tidal walk for visitors. For this walk, i was leading a group of students from the ITE Green Club and two of their teachers and my group was called the puffer fish, one of the five new group names we have for 2008.

So here's some of the things we saw, first 'discovery', a hairy crab! As i said, not the same crabs we get from Sri Lanka =P (picture below)
Discovery Note:
1. The hairs of the hairy crab traps sediment so it blends 'almost' perfectly with its surroundings.
2. We also call this crab the ‘teddy bear crab’. =)
3. The hairy crab eats seaweeds and poisonous zoanthids, which makes the crab mildly poisonous too!


Second 'discovery' is this very beautiful heart cockle which one of our hunter seekers, ST, found (picture below).
Discovery Note:
1. The cockle lives in sand and mud in shallow water.
2. All cockles are hermaphroditic, which means they possess both the male and female sex organs.
3. Show your love by not taking them away from their homes as they are a rare find on our shores. =)


And amongst one of the pool around the zone, we saw this fan worm (picture below), third 'discovery'!
Discovery Note:
1. They get their common name from the appearance and structure of their modified tentacles on their head.
2. These modified tentacles are used for feeding. By the way, they do filter feeding.
3. They retract almost instantly into their tubes at the sense of any movement, shadow or danger near them.


And as we walked further nearer to the reef edge, there were these mushroom corals (picture below) which our sharp-eyed hunter seekers spotted. Fourth 'discovery'.
Discovery Note:
1. Most mushroom corals do not form colonies like most other corals and most mushroom coral is usually a single polyp.
2. Unlike most corals, most mushroom corals are attached to the reef only when they are small.
3. As larger individuals, they will detach themselves from the reef (if they had attached themselves to the reef) and live loose on the seafloor.

Our hunter seekers for this trip were really had "two brushes"
(which means really good). They managed to find this hardly seen nudibranch, fifth 'discovery', which i only seen one on Feb 2007 on Semakau (picture below). It was too bad i didn't had the time to take a better photo but hopefully i will see it soon again. =) Discovery Note:
1. Nudibranchs are essentially snails without shells, and their name literally means "naked gills".
2. In most species, the gills are prominently displayed on their dorsal (upper) surface.
3. They have a pair of tentacles (called rhinophores) located on top of their heads, which biologists believe are used as sensory organs to assist in finding food and seeking a mate.
4. This nudibranch (picture above) might be the
Ceratosoma sinuata.

Lastly but not the least, the star of the walk and i mean it. The knobby sea star! Sixth 'discovery'! Here's a traditional group shot of the star with my really cool group (picture below).
Discovery Note:
1. They get their name from the knobs they have.
2. Although most of them are mostly red or orange in colour, beige or brown coloured knobbly sea stars have been spotted before also.
3. Can you believe that a knobbly seastar might be larger than your face? It’s about 30cm across! (look at the picture above to get an idea)
.

Finally, would like to thank all the puffer fishes for being such a great audience and the positive comments. I hope you enjoyed this trip like i did! =)

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