Sunday, November 25, 2007

Discovery @ Changi Beach on 24 Nov 2007

Thirty second Discovery posting:

(Entry @ 25 Nov 2007: Got the ID for fifth 'discovery')
(Entry @ 27 Nov 2007: Got the ID for sixth 'discovery')
(Entry @ 28 Dec 2007: Got the ID for third 'discovery', thanks to Ria! and correction of ID for seventh 'discovery', also thanks to Ria => )

While everyone else was out at different places on Saturday, Team Seagrass at Semakau, BWV at Kusu, i decided to make a visit to Changi Beach, since i have not visited there for a few months and wanted to check out what could i find there on a late afternoon low spring tide there.

Upon arrival, i saw quite a number of people at the site (picture below)
There were also people standing way out throwing nets out into the sea, isn't that disallowed... (picture below)And there was one group which really attracted my attention (picture below), they grabbed my attention as 1) they were looking into some containers which seem to contain something, 2) most of them are kids and it seems to be a family group. So to satisfy my curiosity, i slowly walked over to where they were.On the way, i spotted a number of beautiful button shells, so here's first 'discovery' (picture below).
Discovery Note:
1. A button shell usually lies beneath the sand, sticking its eyes and a tentacle above the sand to gather food.
2. They bury themselves with their flexible, leaf like foot. Its smooth, round shells helps them to slide quickly into the sand.
3. It is said that no two button shells look alike.
4. But don't pick them home, even empty ones, as empty sea shells can be homes for Hermit Crabs.

Speaking of hermit crabs, second 'discovery' is a stripped hermit crab which i found not far away (picture below)Plea from Hermit Crabs
" We have hard shell only at our front part but a long soft abdomen. To protect our soft butt, we need to tuck it into an empty snail shell as a home. Without a home, we will be naked and thus vulnerable, making us an easy meal... sob =(. So please don't pick up sea shells."

Third 'discovery' is a kind of anemone which i spotted just next to the hermit crab (picture below). Can anyone help me to ID this anemone, i'm not good at them. Thanks!

Entry @ 28 Dec: This is a peacock anemone!
Discovery Note (General Notes about anemone):
1. They are cnidarians like corals and jellies (jelly fish).
2. Why would you not touch a jelly? Cause they have stinging cells! And anemones also have stinging cells too, so don't touch them with your bare hands please. =)

Upon walking close to the group i was mentioning earlier, i took a look at what were they looking at. It was a sand star.

After a short chat with some of them, i found out that they were actually at Changi Beach to look at marine life and learn more about them. And most importantly, they will release what they found back into the sea before leaving. =)

So with my worries aside, here's the fourth 'discovery', a sand star (picture below).
Discovery Note:
1. The tube feet of sand stars end in points instead of suckers.
2. These pointed tube feet push down powerfully allowing Sand star to ‘race’ rapidly over the sand and burrow quite quickly.

I'm not sure about the ID of fifth 'discovery'. It looks like a moon snail (picture below). C
ould anyone confirm if i am correct or wrong. Thanks!

Entry @ 25 Nov: This should be a headshield slug, a Hydatina amplustre. Thanks to Juan Hui for the ID => )Discovery Note (Entry @ 25 Nov 2007):
1. The front of the head shield is developed into a pair of tentacles on each side.
2. It has a shell with alternating pink and white spiral bands, separated by narrow black lines.

Read more about them here @ sea slug forum and here also (another website).

Sixth 'discovery' is something i'm not sure too (picture below). Looks like i still to learn more plus brush up about Inter-tidal stuff. Can anyone help me? Thanks! =)

Entry@27 Nov 2007: According to Ron, this looks like a fan shell. Thanks!Discovery Note (Entry @ 27 Nov 2007):
1. Usually they should be buried in the sand with only the boarder edge sticking out.
2. According to others and my own sighting, it seems fan shells are being collected by people for food. Fan shells are already threaten due to lost of habitat, won't collection worsen the problem...

As i walked around to explore further, i came across this flatfish which was caught on a stray fishing line, i tried to pull the hook but was unsuccessful, so i decided to ask for help from the family i met just now to check if they had something to cut the line.

Still, this is the seventh 'discovery' (picture below).

Entry @ 28 Dec: The ID for this should be flathead.Discovery Note (Updated):
1. Flatheads are notable for their unusual body shape, upon which their hunting strategy is based.

2. Flatheads are dorsally compressed, meaning their body is wide but flattened and very low in height.

3. Both eyes are on the top of the flattened head, giving excellent binocular vision to attack overhead prey.

4.Flatheads use this body structure to hide in sand, with only their eyes visible, and explode upwards and outwards to engulf small fish and prawns as they drift over the hidden flathead

Side Note:

1. People who fish, please clear all your fishing lines and don't leave them behind.
2. Better yet, stop fishing if you can.

After we (the families and myself) had freed the flat fish from line (we could only cut the line, hoping it could survive although the chance is not high =( ), a brittle star appeared, eighth 'discovery' (picture below).Discovery Note:
1. Related to and like the sea stars, they have five arms and a central disc.
2. As the name suggests, the arms of the brittle stars are rather liable to break. This is actually an escape mechanism. They can regenerate their arms, but slowly.
3. Brittle stars use their arms for locomotion. They do not, like sea stars, depend on tube feet.
4. Brittle stars move fairly rapidly by wriggling their arms which are highly flexible and enable the animals to make either snake-like or rowing movements.

Very soon, the tide started to rise, so all of us decided to leave the shore and head for washing up.

Near the washing point, i spotted this strange looking flower and decide to take a photo of it (picture below). Anyone knows what is this?
Although i didn't see as much things as hoped in this trip, i got to know some new friends, the families. And i would like to thank them for giving me a ride out =). Thanks!


tHE tiDE cHAsER said...

Wow! A headshield slug! That's a good find! I prefer its other common name though - bubble shell - much cuter :P

Your 6th discovery looks like a fan shell. Heard from Samson that he saw someone yesterday pulling one out from the sand at Changi. Sadly, that's probably a gone case. Fan shells usually anchor very tightly and pulling them out in fact tear their body issues and will probably kill them.

juanicths said...

more stuff on the head shield slug:
- common one for this species is double-banded bubble, found on reef and sand flats
- eats worms

DreamerJuly said...

Thanks for the ID and info, everyone!

Ron > Btw, i also saw someone pulling out fan shell for food.

Someone else did advice him not to do that, but to no effect =(