Saturday, July 26, 2008

Semakau Walk on 23 July 2008

This is one of those overdue posts again, as I was really busy last week :P

Went to Semakau Landfill again on Wednesday, but this time round, as a hunter-seeker. Didn't have time to take many photos, so here are just some of the interesting stuff that I managed to capture with my digicam.

nudibranch, Glossodoris atromarginata
Found this cute glossodoris nudibranch (Glossodoris atromarginata) on a black sponge when I was crossing the seagrass meadow. This nudibranch can secrete a milky chemical to make it distasteful when it is stressed.

sand-sifting sea stars, Archaster typicus
The sandy area after the seagrass meadow has lots of sand-sifting sea stars (Archaster typicus). These sea stars can burrow into the sand to get away from predators and also to feed on organic particles (aka detritus) in the sand.

moon snail, Polinices mammatus
Here's a moon snail (probably Polinices mammatus) and a sand collar (moon snail egg capsules). Moon snails are fierce hunters that feed on other shells.

starfish, knobbly sea star, Protoreaster nodosus
I managed to find one of our regular knobbly sea stars (Protoreaster nodosus) near the reef crest. Knobbly sea stars are usually the highlight of our guided walks, as they are probably the biggest sea stars that you can Singapore waters.

starfish, cushion star, Culcita novaeguineae
I also had another star find that day - a cushion star (Culcita novaeguineae)! After comparing the photos, this appear to be the same cushion star that we last saw in March 2007!

starfish, knobbly sea star, Protoreaster nodosus
And the cushion star wasn't the only old friend who appeared that day. We also found this knobbly sea star which we last saw in June 2007! However, this one doesn't look too healthy. Some of its knobs have become black patches, though from the arrangement of the remaining knobs and the black spots I could still tell that it's the same sea star. Have no idea what's happening to it.

Nudibranch, Discodoris lilacina
Here's another nudibranch we found, a Discodoris lilacina.

Noble volute, Cymbiola nobilis
And I saw at least 6 noble volutes (Cymbiola nobilis) with their egg capsules!

Cowrie, Cypraea ovum
There were several cowries too. This one looks like an ovum cowrie (Cypraea ovum) to me.

synaptid sea cucumber
When we are heading back, I managed to grab a photo of the synaptid sea cucumber (Synaptidae) feeding on detritus with its tentacles among the seagrass.

On the whole, it was a good trip, despite the fact that it rained for quite while. Must say that we were really lucky that the rain eventually stopped and we managed to see some "old friends" during this trip!


ChrisM said...

That is an OUTSTANDING shot of a synaptid....

Ron Yeo said...

Thanks Chris! :)

Anonymous said...

i went to changi beach for our school's national day event, cross country run. i was on duty at the far side of the beach near the place u brought us to for our electives. it was not a low tide, but i saw a horseshoe crab, many ball sea cucumber and sand dollars. no starfish though.


Ron Yeo said...

Nice :)

Glad that you keep a lookout for nature stuff when you have the opportunity!