Pulau Semakau with Dr Dan and friends

Dr Dan is back in Singapore! With a wonderful group of students from Duke University, and Dr Stan, who has already been furiously blogging about their trip here.

Dr Dan had made a special request to visit Pulau Semakau, and I was glad to be there today, together with some Semakau guides.

Here's the happy group, safe at the mangrove tree in the middle of the sandflats, after having survived running the gauntlet of a gazillion mosquitos, and then the sandfly zone.Alas, even before we could begin, we saw an huge driftnet on the shore.And as we crossed the seagrass meadows,
We met the man who laid out the drift net.
He was dragging a huge container behind him. And it was full of fishes!There was a big garfish, lots of perch and rabbitfishes, a few parrotfish, plus some other fishes I don't really know.
I chatted with him and found out that he lays out the driftnet twice a day during spring tides, at two different locations at Semakau. He works nearby. He was a pleasant guy who seemed to take simple pleasure in his catch.

Today we explored parts of Semakau I have never been to. Semakau is really huge and there are lots of parts that are totally new to me. How exciting!

On the way out to the reefs, Dr Dan finds a sea anemone with Nemos!

Soon, Dr Dan does his crab thing. To the fascination of all in the group.While some of the Semakau guides found all kinds of things for the group to take a closer look at.We saw a whole bunch of amazing stuff, and learnt all kinds of things from Dr Dan, like why corals flouresce at sundown (something to do with photons jumping and cholorophyll being damaged during the day).

But I was struck by what Dr Dan asked me, "How often do you see something new when you visit the shore?". Now that I think about it, I see something new almost everytime I go out.

So, here's some of the special stuff I saw today.

Dr Dan spotted this small bright orange sea cucumber! I have no idea what it is.
One of the Semakau guides also spotted this large sea cucumber.It's been regularly sighted by the Semakau guides but it's my first time seeing it. According to Dr Lane's "A Guide to Sea Stars and Other Echinoderms of Singapore", it's the Ocellated sea cucumber (Stichopus ocellatus). It is identified by its squarish cross section, large white spots with a dark centre in two irregular longitudinal rows on the upper surface, and tube feet in three distinct longitudinal groups on the underside.

And indeed, you can see the three zones of little black tube feet on the underside. Dr Dan is having a look at the underside to check for parasitic snails that burrow into these poor beasts. Fortunately, this one doesn't seem to be infested in this manner.
Dr Dan specifically wanted to see echinoderms.

So it was a good thing that we saw lots of the regulars. We saw several thick long synaptid sea cucumbers that look like intestines, lots of HUGE sandfish sea cucumbers (Holothuria scabra) and a Stonefish sea cucumber (Actinopyga lecanora) with a white ring around the butt and teeth around its anus. We also saw the Common sea stars (Archaster typicus) doin' the sea star thing. And on the way home, Chay Hoon spotted a juvenile Knobbly sea star (Protoreaster nodosus).

Semakau of course has an amazing living reef. And some of the special corals I saw today included this bright blue Caulestrea sp.And a bright pink Acropora sp.!

And Dr Stan spotted the rarely seen Euphyllia glabarescens. So far, I only seem to spot this coral regularly at Semakau and not on other shores.While the better known Anchor corals such as Euphyllia ancora has U-shaped tentacle tips, this coral has a blunt tentacle tip.

Of course, there are the obligatory slug sightings of all manner.
A pair of slugs in pajamas, Chromodoris lineolata ... hmm...possibly doin' the slug thing. And several frilly Glossodoris atromarginata.

One of the ladies spotted a really tiny nudi! I have no idea what it is. What great spotting!And later on, another of the sharp-eyed guests spotted this really fat Jorunna funebris. Did it just eat something enormous? I've never seen something like this before.Chay Hoon also shared an ENORMOUS upside down jellyfish. My first time seeing such a huge one.This animal purposely turns itself upside down. Whereupon it is really hard to spot!All too soon, it was Octopus Hour at sun set...and moon rise!And of course, we did spot octopuses!
But the most special find of the day was this hairy crab eating a bristle worm! I believe Dr Stan spotted it. Wow!In seconds, the crab had dragged the worm into its hidey hole in the living coral. Amazing!

After a last look at Semakau in the glowing lights of the petrochemical plants on Pulau Bukom nearby.We had a few last adventures on the soft mud with a lost shoe and more mosquitos. Before we headed home for dinner!

What a great day out, and such a treasure to share it with Dr Dan, Dr Stan and all our new friends!

Other blogs about the trip
Mini cowry on the manta blog
Sea horse, frogfish and nudis on the colourful clouds blog
Big sea star, horseshoe crab, sand dollar and more on the discovery blog
And lots more creatures and info on the tidechaser blog