Sunday, February 10, 2008

Discovery @ Semakau on 8 Feb 2008

Forty Seventh Discovery Posting

In preparation of the first public Semakau Inter-tidal walk on 23 Feb 2008, a whole batch of current Semakau Guides and new trainees were out at Semakau today (8 Feb 2008).

Here's part of the group just crossing the 'starting point' of the forest trail to reach the Inter-Tidal area on Semakau (picture below).
And while the rest of the gang were out exploring, Ron lead a group of trainees for their practical session and I was kinda of arrowed to do hunter seeking.

Here's first 'discovery', the common sea star, Archaster typicus (picture below).

Discovery Note (Warning: Sex Content):
1. This is a 'mating' position for the sand star.
2. The 'mating' position for the common sea star works like this: the male will be on top of the female, their arms in a formation as in the picture.
3. But they do external fertilization, which means their sexual organs don’t come into contact and the closeness is to increase the chance of fertilization, when they release the eggs and sperms into the water.
4. This 'mating' position is consider unusual in the world of sea stars, as only the common sea star and one other related species is known to “mate” in this way.

I think second 'discovery' looks like some egg capsule (picture below). But still not sure at this point. Can anyone enlighten me?
Yesterday at Hantu, i saw a Spiral melongena laying eggs on Pulau Hantu. This time, it was a volute laying eggs (picture below)! Third 'discovery'.
Discovery Note:
1. Volutes are carnivorous.
2. They prey on bivalves, enveloping the victim completely with their foot forcing the bivalve to finally open from exhaustion and lack of oxygen.
3. They can grow to more than 20cm and used to be common but now threaten due to 'harvesting' from humans and habitat lost.

Here's the trainee group in action and with Ron showing them something (picture below), i can't remember what it is though... haha =P
Anyway, as i continue to walk on to look for interesting things, an octopus moved past my legs. And before it could hide itself under a rock, i quickly took a shot of it (picture below). Fourth 'discovery'.
Discovery Note:
1. Octopuses are characterized by their eight arms (not tentacles), usually bearing suction cups.
2. They have a relative short life span, and some specials live for as little as six months.
3. They have three hearts! Two pump blood through each of their two gills, while the third pumps blood through the body.
4. They are also highly intelligent, probably more intelligent than any other order of invertebrates (any animal without a spinal column).
5. They are also able to change their body colour to camouflage themselves.

View a video about these colour-shifting abilities of sea creatures here.
Do watch it as it amazed me. =)

Anyway, as i walked on. I came across the fifth 'discovery', the sandfish sea cucumber (picture below).Discovery Note:
1. The popular Chinese name for sea cucumber is haishen, which means, roughly, ginseng of the sea.

2. Being related to the sea stars, sea cucumbers have a soft, wormlike body and range from a few centimeters to 90 centimeters in length.
3. Unlike the sea star, however, they have no arms but use a cluster of tube-like feet around their mouth to gather food.
4. To repel predators or when stressed, a sea cucumber might expel their innards or ‘vomit’. And if too much of their innards are expelled, they might die off as a result.
5. The sandfish sea cucumber is the species of sea cucumber which people consume. But they contain toxins, so it must be properly prepared before consumption.

Sixth 'discovery' looks like a peacock anemone (picture below).
Discovery Note:
1. They are named peacock anemones because of the many colours and patterns we can find.
2. They are cnidarians like sea anemones and jelly fishes, which means you shouldn't touch them with your hands as they may be stung by the peacock anemone.

As the night came, lots of crabs started to appear, here's one of them, the red egg crab (picture below) and this is the seventh 'discovery'.
Discovery Note:
1. Egg crabs are highly poisonous and contain toxins which are not destroyed by cooking.
2. Since other animals don't particularly want to eat this crab as it is poisonous, it is slow moving and doesn't really bother to hide.

Another crab we saw, eighth 'discovery', is something i don't know its ID (picture below). Can anyone help me?
Finally, as we walked back to the shoreline, we found a clown fish aka Nemo just next to a gigantic carpet anemone (picture below)! Ninth 'discovery'!Discovery Note:
1. The clownfish have a symbiotic relationship with sea anemone.
2. They have a mucus covering that protects them from the sting of the sea anemone's tentacles.
3. This mucus prevents them from being harmed, and allows clownfish to live in sea anemone.
4. Clownfish are hermaphrodites (they develop as males first and mature as breeding females or ‘change’ into a female if there are no females).
5. More information? Click here.

Would like to thank CH, JH, HW, Ed, CK who were exploring around, for making my job easier as a hunter seeker by telling me where to look for things they found, Luan Keng for organising this trip and all others!

Oh, would also like to thank Andy for giving a few of us a ride which saved us lots of time in getting home. =)

a) Tidechaser's blog entry on other interesting things on Semakau.
b) Manta's blog entry on two nemos at two different locations on Semakau.

Another group of shore lovers were out on Kusu, and check out what they saw on
a) Wildfilms blog
b) NatureScouter's blog.

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