10 January 2009

Cyrene in high water

Tide high? Can go to Cyrene?
Here's our answer!

Though there was just a sliver of Cyrene at this not-so-low tide, Melvin and his Can-do boat takes the intrepid Star Trackers out to this only daylight, non-weekend slot for the month.It's a bit tricky with high winds and high water, but we all make it safely to Cyrene thanks to Melvin! It was also a pleasure to be joined by Subaraj, Samuel and Sonia. As well as Pamela who was with the earlier load of Star Trackers.It sure was high. Nothing was sticking out of the water aside from a very narrow strip of sand bar! The Star Trackers nevertheless went on tracking them stars. Even in thigh-high, choppy water. They still found and measured 100 stars!

The marine life of Cyrene Reef is just amazing. Despite it being located right in the middle of port, surrounding by Pasir Panjang terminal, Jurong Island and Pulau Bukom.
The reef is also affected by massive dredging and blasting nearby as well as the humungous reclamation for the Pasir Panjang port extension.

As the waters went down, a little, the Star Trackers found some really special stars!According to Sijie and Chee Kong, these are Pentaceraster sp., not necessarily the famous first-record-for-Singapore Pentaceraster mammilatus of Cyrene Reef.The special feature about these stars are the spiny bits on the tips of the arms.
I came across this one which had been seen previously.And Sijie found this one with orange accents. A little later, the team found a green one! Read Mei Lin's fantastic post about all four special stars seen on the trip!

Knobbly seastars (Protoreaster nodosus) are everywhere! These are the species that the Star Trackers are tracking. So much so, I only look at the special ones.Like this one with six arms! (The 'normal' ones have five arms).And four arms.This one looked like a plus sign!

Cyrene has strange echinoderms. This one looks like the commonly seen Garlic bread sea cucumber (Holothuria scabra).But it had odd markings on the front and just looks a little different.I'm not really sure what this is.

Subaraj later on shared this sighting of another sea cucumber which looks somewhat similar with big blotches.Hmmm...what are these animals? Cyrene is just amazingly full of strange echinoderms.
The white sea urchins (Salmacis sp.) were back, although well hidden by bits of shells, seaweeds and seagrasses that they carry.
Disturbingly, we saw quite a lot of dead sand dollars during the trip. Some parts of the seagrasses were littered by the white skeletons of these flat, disk-like animals. I hope this is just a natural phenomenon. This is why it's important to visit regularly so that we have a better sense of seasonal events.

Special molluscs encountered today include this very pretty Lined moon snail (Natica lineata). My first sighting of this snail on Cyrene Reef, which is more usually seen on our Northern shores.
These odd, shelled animals that look like weird tongue-depressors are bivalves!
Sijie showed me one and after that, I kept seeing them all over the seagrass meadows. Chee Kong tells us its the Hammer oyster (Malleus sp., Family Malleidae). The shell has a wavy edge (see Mei Lin's post for a photo of this). It is considered common in the Indo-Pacific, found in shallow waters near reefs. But this is my first time seeing it. Perhaps these animals were always there, but I just didn't see them! Amazing!Nudibranchs are of course our favourite molluscs. But I didn't any today aside from this one Discodoris boholiensis that was actively moving among the seagrasses. Subaraj, however, found a Melibe nudibranch (Melibe viridis)! So it looks like they are coming back into season.There were several shells of what looked like cone snails on the rockier parts of Cyrene. I looked (carefully, as these snails are highly venomous) but could not find any living snails. The Star Tracker team, however, found a living Sundial snail! (see Mei Lin's post for a photo of this). And Subaraj found a small octopus which he shared with the team.

The high water allows us to see some of our favourite marine life in a more natural state.The Tape seagrasses (Enhalus acoroides) were blooming again. And here, in the high water, we can see clearly how the petals of the female flower 'zip' up together underwater, and spread out on the water surface at low tide. More about this on this earlier post.

While all of us were focused, head down on the sand, Subaraj saw lots of fabulous seabirds including a heron catching a big fish (we hope to read more about this in an upcoming Bird Ecology Study Group blog entry) and a falcon that swooped over us. Sigh. There's so much to see on Cyrene, we just can't keep up.

But high waters, exacerbated by high winds, made it important to start going home on time. Here is Melvin heading into the shore to fetch us.The gentlemen let the ladies take the first trip home.While they wait in the fast disappearing reef for the second trip. And a rope got stuck on the propeller of the boat on their trip in! Fortunately, Melvin could free the boat even though no one had a knife! Wah! Every trip to Cyrene sure is an adventure. And the boat sure lives up to its name!

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