Monday, March 16, 2009

South Cottesloe Beach - Pretty fan worm

14 Mar 09

This morning I snorkeled at South Cottesloe with a new friend, Wehdi. We spent some time exploring the shallow reef in the south of the second groyne. Later, after he left, I continued snorkeling at the other side of the groyne too.

The wind was not too strong. The water was quite calm and visibility was not too bad, except that it was a little chilly underwater today, as compared to last Sunday.

And today I bumped into a HUGE school of common buffalo breams (Kyphosus sydneyanus). It could easily be hundreds of them! As I was taking photos of them, I suddenly noticed that they were forming a circle around me! It just happened for a few seconds and the circle broke up by the time I set my camera to underwater video mode! But that few seconds were unbelievable! I have seen a southern eagle ray done that but not hundreds of buffalo breams! This was definitely the highlight of today's snorkel.

And I saw a huge school of western striped trumpeters (Pelates octolineatus) on the shallow reef too. Watching a huge school of fish swimming past or scavenging the reef for food is always an enjoyable experience for me.

As I was exploring the reef, I noticed that there were more marine worms, especially tube worms or fan worms around than I initially thought.

The crown of this fan worm (also called feather duster worm) is about 6-8 cm across.

A close-up on the crown:
The feathers are tentacles with tiny hairs (cilia) on them.
The animal uses the beating hairs to drive water through the feathers. The cilia get the food particles in the water and pass them down to the mouth in the center of the crown. The animal not only uses the tentacles to filter feed, but also to breathe!

More common than the pretty feather duster worm on the reef is the Protula species tube worm. This worm is smaller than the previous one which has a pretty crown. This one is 2 cm or so across.

And I also saw this curious fan worm look-alike! The tube seems to be buried within the sponge. Black feathers! For a while, I thought somebody has buried some plastic gadget into the reef.

When I was on my way back to shore, I also spotted a huge school of wordward's pomfrets (Schuettea wordwardi).

I did see a southern eagle ray (Myliobatis australis). But the nearshore visibility was really poor, as you can see from the photo above, so I decided that there's no point taking a shot. On the other hand, I did take a few shots of a squid, but it just didn't turn out alright, so I can't put them up too : (


Denis Wilson said...

Hi Chai
I spent a couple of happy hours on the weekend,looking at marine life below a raised boardwalk at Narooma (NSW South Coast). I saw a small Octopus (possibly not the famous Blue-ringed Occy), several small Eels, a Black Ray, and lots of small fish - Toadies and another I cannot recall its name.
The next day, I went snorkelling - yes me - in a fenced off area within the Estuary. Lots of small Bream, Sand Whiting, Blackfish, etc.
Then there was a visit by a seal. I was out of the water by then, but I got a photo of it, close to the rock wall.
Very exciting for a "land-lubber" like myself.
Nice photos of your schools of fish. That reminds me, I was totally surrounded by a school of "bait fish" at several stages. Tiny things which swam past me, much better than I could swim past them.

Tsun-Thai Chai said...

Wow! Denis, you were in a marine life paradise! There's so much to see!