Where Discovery Begins: Semakau Inter-Tidal Walk on 08 Feb 2009

Eighty Sixth Discovery Posting:

Banded together with a group of 'turtles', we (including myself) were out at Semakau for its first public guided walk in 2009. Here's a group photo of everyone and Diana, my 'lovely' assistant of the day (picture below).

Due to personal time restrictions, I have chosen some of more interesting things seen on the day by my group. And if you are interested to discover what other things other visitors saw on this trip, I have include a extra section with links to blog entries on this very same trip.

Anyway, down to this posting, our first 'discovery' of the day is this extraordinary sea hare (picture below).

Discovery Note:
1. From what I know, they are herbivores. This means they eat sea grass or maybe even sea weed.
2. They have the ability to eject purple ink when in danger or stressed.
3. There is an interesting account by ST on how he found this sea hare. If you are interested, you may visit http://mantamola.blogspot.com/2009/02/attack-of-hairy-pincer.html.

And our second 'discovery' are a number of sea stars. Here's one of them covered in partial shade (picture below).

Discovery Note:
1. Their tube feet are interesting as they are used for walking, handle food as well as breathing, and probably to catch prey as well, talk about multi purpose!
2. Sea stars get stressed when out of water, this is because while we have blood circulating our bodies, they have sea water circulating their bodies.
3. They are not as common as their name suggests. This is due to past over-collection and habitat lost past and present. So don't take them away from their homes when you see them. =)
4. Some sea stars are predators that prey on worms, crustaceans and bivalves while some are known to eat decayed plant matters.
5. Many sea stars eat with their stomach outside their body. When doing this, their tube feet will pull the two shells of a bivalve apart. And while still attached to their prey’s body, they extend their stomach out through their mouths into the bivalve shell.
6. You can read more about them @ http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/archaster.htm.

Our third 'discovery' of the day is a relative of the sea stars, a sand fish sea cucumber! (picture below)

Discovery Note:
1. The popular Chinese name for sea cucumber is haishen, which means, roughly, ginseng of the sea.

2. They have a soft, wormlike body and can range from a few centimeters to even 90 centimeters in length!
3. 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.

4. Read more about this sea cucumber @ http://www.wildsingapore.com/wildfacts/echinodermata/holothuroidea/scabra.htm.

And presenting our fourth 'discovery', which is a creature we haven't seen for quite a while on Semakau (drum rolls...). May I present to you, the heart cockle (picture below)!

Discovery Note:
1. If you take a closer look, you will notice that the opening of the valves 'cuts' through the center of the heart.
2. Some turtles were saying that the heart cockle is in a state of 'heart-brokeness' when its valves are opened...hahaha...
3. Anyway, you can read more about it @ http://www.wildsingapore.com/wildfacts/mollusca/bivalvia/cardiidae/cardissa.htm.

We were also really lucky to spot the yet-to-be identified sea star again. Fifth 'discovery' (picture below).

Guided walks have always been made easier due to the hard work from our hunter seekers. And we have to give them great appaulse for finding this tigertail sea horse (picture below). Sixth 'discovery'.Discovery Note:
1. They are hard to find as they are well-camouflaged.
2. Do you know that a seahorse is actually a fish? Yes, it is, but instead of having scales, they have an inflexible armour of overlapping bony plates.
3. A seahorse cannot swim faster because it doesn't have tail fin and pelvic fins like other fishes, thus it is well-camouflaged. But they can make a short burst of speed if in danger.
4. They may look harmless, but they are actually quite voracious predators. It sits in wait and ambushes on any tiny animals that drifts or wander by.
5. They have a very simple digestive system (no stomach) thus they need to eat almost constantly. Baby sea horses are known to eat thousands of tiny shrimps in a day!
6. And of course, the most well-known fact of the sea horse is that the male can get 'pregnant', this is because the female seahorses lay eggs in the pouch of a male seahorse and it is in their where the eggs will be fertilized and then the male seahorse will carry them till the eggs hatch.

Seventh 'discovery' is a flat worm... (picture below)

Discovery Note:
1. Flatworms are hermaphrodite, which means a flatworm has both the male and female sex organs.
2. And certain species of flatworms engage in penis fencing, in which two individuals fight, trying to pierce the skin of the other with their penises; the first to succeed inseminates the other, which must then carry and nourish the eggs.

And the last but not least eighth 'discovery', I decided on eight as it was still during the Chinese New Year on the day of the walk, is a polka-dot nudibranch or called as cookies and cream by one of the turtles...hahaha (picture below).

Discovery Note:
1. 'Nudibranch' means 'naked gills'. The name comes from the flower-like gills found on the back of many nudibranchs. These nudibranchs use the gills to breathe.
2. Nudibranchs are related to snails. Little baby nudibranchs are born with shells, but they lose them when they become adults.
3. Most nudibranchs are carnivores, they eat immobile or small, slow-moving prey. Examples are sponges, ascidians, hard corals, soft corals, sea anemones etc.

4. To protect themselves, some produce distasteful substances, toxins and even acids. They advertise this with bright warning colours. Others are camouflaged to match their surroundings. Those that eat colourful creatures such as sponges or corals, may themselves be colourful to match their prey. Being small and flat, they can also easily hide in narrow places.
5. Read more about them @ http://www.wildsingapore.com/wildfacts/mollusca/nudibranchia.htm.

Lastly, here's a group photo of everyone with the knobbly sea star (picture below). Thanks to R for helping us to take this photo. =D