113th Discovery Posting:
The evening low tides for us to visit the shores have come and past. From now till September, it is time for us inter tidal goers to wake up at sometimes insanely early hours just to catch the tide. And over the last long weekend, I woke up from 4am to 5am for three straight days of inter tidal walk. Here's the first of them,
On Good Friday (2nd April 2010), RMBR conducted its first guided inter tidal walk on Pulau Hantu for public participants and I was the guide for the group, nudibranch.
One of the few animals that captivated my group was the fiddler crabs. Here's one of them,
first 'discovery' (picture below).
The fiddler crab you see above is a male fiddler crab. We tell the males apart for their one large pincer that is almost to the same size as their bodies. Females, on the other hand, have two small pincers and they are used for feeding. For the males, because they cannot use their large pincer to feed themselves, they depend on their one and only small pincer for them to feed themselves. However, this is not to say that their big pincer is entirely useless. Their big pincer, in fact is used to attract female fiddler crabs and to intimidate other males.
Moving on, our
second 'discovery' was this jellyfish found by our hunter seekers (picture below).
Some jelly fishes or jellies (since they are not related to fishes =P) are seasonally abundant. According to our observation, this (above) is one of them which you can find in numbers especially in the first few months of the year. By the way, jellies have stings, and some can cause bad reactions (if you are unlucky, maybe death), so never handle a jelly with your bare hands.
Our
third 'discovery' '
was this really little brittle star which I held in my hand for a little while (picture below).
As their name suggests, they are really brittle, they can break their arms if they feel danger. They are also not often seen as they hide either under rocks, within sponges or on other animals. Oh, they are also related to sea stars. To be more specific, they belong to the echinoderm phylum like the sea stars and they are the largest group of creatures within this phylum.
Belonging to the group of nudibranch would mean that seeing one of them would make the trip even more interesting for the group. And boy were we lucky, we saw a total of 4 different species of nudis (pictures below).
Fourth 'discovery'.
Here's the lined chromodoris nudibranch (picture below)
phylid nudibranch (picture below)
Polka-dot nudibranch (picture below)
Black-margined glossodoris nudibranch (picture below)
If you are wondering, nudibranchs are sea slugs and they belong to the phylum of molluscs (a familiar animal found in this group would be snails). Now you might be asking, where's the shell for a nudibranch if they are related to snails? Actually, they do have shells. But it is only when they are young. When they are older, they lose their shells, one kind of defence, to get another form of defence, venom or stings depending on the species of nudibranch. So never handle a nudibranch for your own safety. =D
The last,
fifth 'discovery' is the feather star (picture below). It looks much better than this if it's submerged in deeper water.
As their name suggests, their arms are a little like feathers, handle with care as they may break easily. I have seen them in many different colours besides red. They include black, yellow, white, etc. They are also related to the sea stars being in the same echinoderm phylum.
Finally, here's a group photo of all the nudibranch (picture below).
Before I end, it's thanks to all who came and Kimberly who was my OJT and helped a lot during this trip =D
Extra:a) Read RY's entry for this trip:
http://tidechaser.blogspot.com/2010/04/first-intertidal-walk-at-pulau-hantu-on.html
Cowries have a really beautiful shell and in the past, Polynesians have used them as some cowries as a form of currency. Till today, some people still collect them, not to use as money, but to sell them for money.
Fourth and Fifth 'discoveries' would be the cushion and knobbly sea star which my group, herons (if I remembered correctly) took a picture with (pictures below)
Do apologize to all Herons, students from Jurongville Secondary, for such a late posting. Nevertheless, I had a great time with you all despite it being a rainy morning. =D
