Jul 1, 2007

Underwater mushroom garden at Hantu

There's a mushroom garden at Pulau Hantu! In all colours of the rainbow, and wondrous shapes and textures. Pulau Hantu seems to be one of the few places where you can see most of the different kinds of mushroom corals that can be found in Singapore.
Mushroom corals, like many other hard corals, look their best at night. And wildfilms and beachfleas enjoyed a fabulous display on the reefs of Hantu this morning during a pre-dawn trip.Like other hard corals, the mushroom coral has a hard skeleton. Most have tentacles.
Unlike most other hard corals which are colonies of countless little polyps, a mushroom coral is usually a single LARGE polyp. The mouth is in the centre.Some have a hump in the centre.
Some are elongated.
I don't really have a good grasp of the hard corals yet, but all the above are possibly Fungia sp.

Unlike most other hard corals, mushroom corals (Family Fungidae) live unattached to the surface as adults. Baby mushroom corals, however, start off stuck to a hard surface. These tiny little mushroom corals were hardly bigger than a 50cent coin!This baby blue long mushroom coral is possibly Herpolitha limax. It has a different skeleton structure, with many discontinuous 'lines'. Instead of a long continuous 'line' from the centre to the edges like Fungia sp.
This is another kind of mushroom coral, possibly Polyphyllia talpina, which has yet another kind of skeleton structure.Often mistaken for a sea anemone, the long-tentacled Heliofungia actiniaria is yet another mushroom coral. Besides Pulau Hantu, these are also seen on Pulau Semakau. A really special find, possibly Podobacia sp. This member of the Family Fungidae, however, remains stuck to a hard surface all its life. I rarely see this hard coral elsewhere.Hantu is also one of our accessible islands with good growths of hard corals rarely seen elsewhere. Such as this magnificent wreath of Pavona sp., sometimes called Lettuce coral.
There were some Acropora sp., but they were small. Nothing like the spectacular Acropora Overdose that we had at Raffles Lighthouse recently.
This beautiful coral is possibly Astreopora sp. (Family Acroporidae) and thus related to Acropora sp. There were several large boulders on the Hantu reef.Always a delight to encounter, a large colony of Euphyllia sp. also called Anchor coral because of the U-shaped tips of the polyps. Although large, this colony was not as large as the ones on Sentosa shores slated for reclamation.
And what a treat for me! To see both anemone shrimp and anemonefish! These two different animals live in sea anemones. At low tide, when the water has gone out, they stay as close as possible to the home sea anemone in whatever pools of water that remain.
It was reassuring to see the 'Nemo'. And later to hear that other anemonefishes were also spotted by the rest of the team. For a while, we stopped seeing them on Hantu. One of our fears was that they had been poached.

Lots of other amazing marine life were encountered! See these blogs for more!
The budak blog about tentacles and feather stars and anemone shrimps
Ron's tidechaser blog for the Tomato anemonefish, sea urchin and sea stars
Kok Sheng's wonderful creations blog for Razorfish and Batfish!

Alas, all doesn't seem well with the reefs. There were a few bleached colonies.
And some looked more yellow than usual. I'm not sure if this something to worry about.
Today, Pulau Hantu was also a little 'quiet', just like the reefs of Sisters yesterday. There was very little sargassum and hardly any other seaweeds. The lagoons were sandier than usual and there were very few soft spots compared to our past visits. The water, however, was a lot clearer than usual. The hard and soft corals seemed mostly there and mostly alright, and there were fishes and other marine life. Perhaps it's a seasonal thing? There's still so much to learn about our shores.

Pulau Hantu is magnificent because it has several habitats. Its reefs are also great for divers: go dive Hantu with the Hantu bloggers! There's also seagrasses, coral rubble, vast sandy shores with sea stars and fiddler crabs and even a small stand of mangroves! Here is a view of the lagoon from the North jetty.
The original reefs of Hantu were sealed off by sea walls with some reclamation to create swimming lagoons. The reefs have started growing outside the sea walls and into the lagoon as well.Just opposite Hantu is Pulau Bukom, the location of a major industrial installation. Pulau Bukom has recently been merged with Pulau Busing (also next to Hantu) by reclaiming a wonderful reef at Terumbu Bayan.A last look at the palm fringed island of Hantu as we leave.
We take the long route around Pulau Bukom because work on Pulau Busing has closed off the shorter route. It's a chance to see how some of our islands are put to work.

Our boatman explains this is a ship being filled up with refinery products. Kind of like a huge petrol station.
This large ship is being filled with asphalt for Vietnam.All along the coast of Pulau Bukom, petrochemical installations and large ships.Are petrochemical plants bad? Consider some of the facts...

Singapore is a major refining centre for Southeast Asia with a refining capacity of double its consumption of petrochemical products. Singapore's strategic location in the Straits of Malacca, a major route for oil tankers, is one reason for this.

Petroleum and petroleum products make up nearly 25% of total manufacturing output of Singapore in 2004 and provides the highest remuneration per worker of all manufacturing activities in Singapore. (Biomedical and Electronics are also considered manufacturing activities).

The boatman also told us that Cyrene Reef (a submerged reef near Pulau Bukom with amazing marine life) would be reclaimed by 2015 to create a tank store.

As he mentioned this, he point out various locations which used to be submerged reefs and have since been converted to industrial uses such as tank stores and container terminals.

What is the future for our Southern Islands?


JC said...

Lovely sightings @ Hantu. Fungiidae family sure are difficult to ID. This link, http://www.marinelifephotography.com/corals/mushroom/fungiidae.htm has a few pix of some of them which might help in your search of proper ID.

Sad to hear that more shore is making way for industrialisation. Hope the boatman's words are juz rumors.

ria said...

Thanks JC. Unfortunately I am really hesitant about identifying hard corals.

Websites, especially of species outside our region, without specific keys and closeup photos or diagrams of corallites, are rather chancy I feel.

Marine biologists who have come with us in the field generally won't commit to an ID. They need to take a sample and look it under the microscope, among others. And even then, given natural variation, it's still a tricky thing.

Regarding the future of our shores, we can only hope for the best, and to appreciate them while we can.