May 21, 2008

Changi Returns

In the cool predawn, we visited a stretch of Changi that we haven't looked at for about a year.What a delightful surprise to be greeted by an abundance of life! This stretch is possibly the last natural rocky shore on Changi. The hard surface provides lots of real estate for beautiful hydroids, sponges and the many animals that live with them.

Such as nudibranchs!We saw four of these pretty little slugs! It is possibly Hypselodoris infucata (and not H. kanga because it doesn't have the spots on the edges of the feathery gills). But there are many nudi species that look similar so we can't really be sure.
This is particularly momentous for me, because I saw this very kind of slug the first time I visited this shore. And have not seen it since. That first visit years ago this shore was exploding with life. It had suffered since, but looks like it's making a comeback.

Kok Sheng also spotted this spotted nudi. We don't really know what it is. Chay Hoon found something similar a while back at Tuas. We decided to call it the "cow nudi" because of the cow-like patches.It was placed in the container for a clear water pot shot because the water here is very murky. Of course, we put it back where it was found after that. It is very important to do this, because nudibranchs generally have a very specialised diet and they may starve if they are moved far away from their food.

Rocks provide a hard surface to cling to, so many animals are found here. You will have to look carefully though, as some are very well camouflaged. Such as this large crab.And these often overlooked sea stars, which we call the Rock star (Asterina coronata).
We saw a few of the black short-spined sea urchins (Temnopleurus sp.) clinging to the rocks.And under stones were cowries, porcelain crabs, all kinds of encrusting worms and sponges, and this strange limpet with an oversized body.You can see the shell in the middle of the fleshy body. It is called the Hoof-shield limpet (Scutus sp.). I saw them often in the past, but for a while they were not so commonly encountered. So it was good to see several during our short trip.

Under stones that are encrusted with sponges, are tiny snapping shrimps!Here is a pair, possibly the bigger is Mama (with the pink thing that looks like eggs) and the smaller Papa. These snapping shrimps too were a common sighting in the past but missing for a while when the sponges disappeared. Great to see them again!

We always look under stones very carefully so as not to hurt plants and animals when turning the stone over. And we always turn the stones back exactly the way they were found. Because animals that live in burrows in the ground also use the stone as protection.

Another old friend to welcome back is this large orange sea cucumber with dark stripes.It has really long tube feet and was seen clinging to hydroids and on stones. These used to be commonly seen. Then they were missing for a while.

A hard surface is also a great place for hard corals.The Zebra coral (Oulastrea crispata) is quite often seen on Changi, although the colonies are small. This coral has a black-and-white skeleton that retains this colouration even after the animals die.

For the first time, however, we noticed these tiny little things that look like individual hard coral polyps all over the rocks in a covered area.They were growing quite apart from one another. Here's a closer look at the skeleton.And the living polyp.Could these be Cave corals (Tubastrea sp.)? Cave corals grow where it is dark because they do not have the symbiotic algae that depend on sunlight for photosynthesis.

The shores are teeming with what seems to be blobs, but turn out to be little sea anemones.They may look boring, but a closer look reveals their beauty.We miss Dr Daphne when we see all these blobs. We should bring her here the next time she visits us. Because the rocks are just covered with these anemones.

The Zoanthids Have Returned!One stretch of this rocky shore used to be literally carpeted with these colonial anemones with pink centres. It was impossible to walk there. Then they all disappeared. But today, we saw good clumps of them back on the shore!

And some clumps were really LARGE!Zoanthids look like tiny sea anemones with a circle of tentacles on top of a tube-like body column. The little animals are connected to one another and thus colonial. When out of water, they tuck their tentacles into their bodies and look like tiny sausages.

Still Missing In Action: We didn't see a single living sea fan. I saw two dead ones still stuck to a rock. There used to be a lot of sea fans at this location. There were also no flowery soft corals.

On the way back, we came across lots of fireworms washed ashore. They were being attacked by tiny bluish springtails!

When we put some back into the water, they began to swim vigorously.
Some of the returned worms, however, were immediately attacked by little swimming crabs! Kok Sheng has photos of the crabs in action on his wonderful creations blog.

All too soon, it was sunrise and the tide came in.What a beautiful beginning for the day,
And dawn of returning life on this rare Changi rocky shore.

Alas, as usual, people continue to leave an impact on this shore.Ivan noticed lots of dead mud crabs. A strange thing to see as these crabs are not usually found in the habitats on this stretch of Changi. He shares his thoughts on the possibility that they were released as part of Vesak Day celebrations, on his lazy lizard blog.

Along the boardwalk, there appears to be accumulations of rubbish.Some people don't seem to take care even of the man-made structures provided for their enjoyment.This lovely shelter was marred by huge burn marks on the wooden floor and wooden benches.To continue to enjoy common property, both man-made and natural, responsible behaviour is necessary. There is indeed still much to be done by way of raising awareness.

Other blog entries about this trip

1 comment:

Liana said...

HAHA ria you so funny. ROCK STAR. the zoanthid clump is freaking huge, weird! lovely nudis, very very pretty!