05 July 2009

Anemone overdose at Kranji

The shores at Kranji Reservoir Park may appear to be dead and lifeless.
But a closer look reveals that it is simply carpeted with sea anemones! As well as all kinds of other tiny animals.

The very soft mud near the high water mark is thickly carpeted in Nest mussels (Musculita senhausia). These tiny bivalves create a 'nest' with their byssus threads that blankets the soft mud. A scummy kind of fine hairy organism, probably cyanobacteria, has grown over the 'nests'.
The blanket of mussles is dotted with various kinds of sea anemones. The largest ones are these pretty anemones with lobes around the mouth, and two kinds of tentacles: longer ones around the mouth and shorter ones under those. It has fine white stripes on its body column.
We're still awaiting the identification of this sea anemone, but I call it the mangrove anemone. So far, I've only seen it at Kranji and Pasir Ris. Here's some that I saw today at Kranji.
I also saw other strange anemones that I've not seen before. Like this one which seems to have branched tentacles.
And another pretty one that is all white with transparent speckled tentacles.
Among these 'larger' anemones (actually, these about only 3-5cm in diameter), were lots and lots of really tiny sea anemones!
As well as a whole host of other tiny critters such as flatworms, beachfleas and tiny transparent bristleworms! Of course, I didn't actually see any of these until I got home and processed the photos.

What was really abundant were these tiny sea anemones.
They come in different patterns and some are two toned.
Here's a view of their striped body columns.
Here's a closer look at one, with all the little animals on the soft mud around it.
And here's another one with its body column. Some have a 'moustache' with a pair of longer tentacles in the middle of the oral disk, so I call it the moustached anemone. We're also awaiting the identification of these animals.
These moustached anemones settle on any hard object that can be found on the shores. On little stones, bigger grains of sand. And of course on other animals. Even on this Mangrove horseshoe crab (Carcinoscorpius rotundicauda)!
The horseshoe crab was very much alive, and so were its hitch-hikers. Here's a closer look at the anemones on the horseshoe crab. Out of the water, they look like a striped blob.
The little anemones also settled on the shells of living snails and shells occupied by hermit crabs. I took a closer look at these animals by putting them in a tray. This living snail (you can see its black proboscis sticking out) was carrying a huge load of more than ten anemones!
Here's a little snail with several anemones. I took the photo of it in a little glass tank.
And here's a bunch of anemones and barnacles on the shell occupied by a tiny hermit crab.
The hermit crab (photo on the left) is smaller than the sea anemone!
And here's a whole bunch of hermits with their heavily encrusted shells. You can hardly see the hermits amidst the waving tentacles of the sea anemones. I guess this is why the hermit crabs put up with the anemones.
The whole assembly is like a moving garden of flowery anemones and feeding barnacles!

Hopefully, when Dr Daphne the world authority on anemones, is in Singapore end of the month, she can sort out these fascinating animals for us!

This shore is heavily harvested for buried bivalves. This morning, in the dark, there were at least three people harvesting on the shore. I could hear them shoveling and digging. During daylight there are many more people doing this.

In addition, driftnets seem to be regularly placed here. I have not visited at a low tide and NOT encountered a driftnet on this shore.
Today, there were already Flower crabs (Portunus pelagicus) in what seems to be a freshly laid net.And this looks like a Tripod fish (Family Triacanthidae). Fortunately, there were no horseshoe crabs in the net. Ivan also recently commented about the littering problem at Kranji.

This morning, there were lots of campers in the tiny park. There was one group of foreign workers chatting merrily, while another group of what seems to be locals were having a guitar sing-a-long in another corner.

Kranji Reservoir Park is managed by PUB and it is one of the reservoirs where fishing is allowed in designated areas. It is also one of the sites where the Japanese landed and battle ensued. There is a memorial in the park to commemorate the Kranji Beach Battle.

1 comment:

  1. omigosh, so many anemones! anemone overload, esp for those snails, almost like parasites. fascinating, how they are showing you their body column, pretty and striped!

    ReplyDelete

LinkWithin

Related Posts with Thumbnails