Nudibranchs, Solitary Coral and Whatnot

Posted in Under the Sea on August 23rd, 2009 by MadDog
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Oh, it’s Sunday morning and here I am at the office posting because Telikom can’t manage a telephone line four kilometres from the exchange that will pass a data signal. They just keep feeding me the same old lies and empty promises.

I went diving on the big reef just west of Kranket Island yesterday. I didn’t see anything exciting. One wouldn’t expect much inside the barrier reef, but it was too rough outside to anchor. The swell was running about a metre with white horses everywhere.

I do like this shot of a few Humbugs (the black and white fish) and some very pretty cyan coloured fish which I’m far too lazy to look up in my book this morning:

Little cyan fishes

There was an exceptionally brave Reef Lizardfish who allowed me much closer that can usually get. I don’t know how many time’s I’ve tripped the shutter on one of these and got only a puff of dust in the frame for my trouble:

A Reef Lizardfish

Nudibranchs were scarce, but I did manage to find a couple of them. This black variety is presents a genuine challenge to get a good exposure:

Nudibranch

The contrast between the black and white is greater than most cameras can handle. It takes some careful fiddling with Photoshop to get it right.

This was, by far, the best shot of the day:

Nudibranch

I’m getting too lazy to look up the taxonomic names of these. That’s a bad sign. I need someone to whip me into shape and get me moving again.

This, believe it or not, is an oyster:

Oyster

Like giant clams, they have light-sensing organs around the edges of the mantle. If you move your hand over it, it will close up and eject a puff of water strong enough to feel it on your hand.

Hmm . . . I got to the end of the post and nearly for the the Solitary Coral and Whatnot part.  At Kranket Lagoon, I wondered how it would be if I took a picture of nothing. Well, not nothing, exactly, just pointing my camera down at the bottom and snapping whatever was there. It turned out to be much more interesting than I thought it would be:

Solitary coral and whatnot

This is a typical bottom in a coral rich area. The predominant shapes are disk-like solitary corals, or mushroom corals, as they are called by some. They are called solitary because they do not attach to anything.

I often see these flipped over upside-down. The coral will die in this position, because it needs the sun’s energy to fuel the algae that live symbiotically with it and provide part of its food. I’m not sure how that they get flipped over. I suppose that some kinds of fish might feed by flipping things over to see if there is anything tasty underneath. I’ve certainly seen Triggerfish do this. Whenever I see a mushroom coral upside down, I turn it back over right-side up, so that it can carry on with its solitary life.

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