Nudibranchs – Can’t Get Enough of ‘Em

No Gravatar

Saturday at the South end of Leper Island  was a good day for nudibranch hunting. There’s not much challenge to hunting nudibranchs, except to find them in the beginning. Sometimes there are a lot of them and sometimes none. I don’t know where they go. The slide around slower than land snails, so motion capture is not a problem. Most of them, however are teensy-weensy. This Chromodoris geometrica  was about 1.5 cm long:

Nudibranch - Chromodoris geometrica

You have to get your camera lens practically right up against the critter to get a shot like this. That means that, with the Canon G10 rig, you can’t use the flash; it’s blocked by the housing.

I was frankly surprised that these shots came out so pretty. The colours are very accurate and I got enough depth of field to get good focus from edge to edge. Here’s another shot of the little fellow going downhill:

Nudibranch - Chromodoris geometrica

The breathing organ (branch) is the feathery thing at the back. The antlers at the front are, I imagine, sensory organs. I’m very happy with these shots, especially since this is the first time that I’ve seen this species.

Here’s something that you don’t see every day, nudibranch eggs:Nudibranch eggsThe cluster is about as big around as a golf ball. If you click to enlarge you will see that is is very lacy. The individual eggs are stuck together and come out in a ribbon. They are always laid out in a circle or spiral shape.

Here’s another nudi for you. This one is a Phyllidiella pustulosa:Nudibranch - Phyllidiella pustulosa (flash lit)I can’t say that I’m fond of the taxonomic name. Anything that starts with ‘pust’ doesn’t appeal to me. The shot above was taken with the flash turned on. For a flash shot, it’s not too bad, though the colours are just a bit off.

Here’s the same critter with the flash turned off. I like this much better:Nudibranch - Phyllidiella pustulosa (natural light)It is much closer to what I actually saw. To me it appears more natural. I sometimes wonder of non-divers ever notice the difference. I suppose that most people just assume that everything is gaudy-bright the way the popular press shows most underwater images. It’s not really that way.

The clown shot of the day is provided by these cute little Striped Catfish (Plotosus lineatus):Striped Catfish - Plotosus lineatusThey travel around in schools and usually line up along a front edge of travel while they pick up tasty bits from the bottom. It’s comical to watch them marching on their whiskery little noses. Ones at the front will break away and move to the back so that their buddies can get to the fresh stuff. Or maybe they just need time to chew. I’m not convinced that fish are altruistic.

Here’s an image that I shot a few years ago up at Mililat Passage  of a river of Striped Catfish:A river of Striped Catfish (Plotosus lineatus)
Cool, eh?

Be Sociable, Share!
Tags: , , , , , , , ,

5 Responses to “Nudibranchs – Can’t Get Enough of ‘Em”

  1. Steven Goodheart Says:

    Damn, I love dem nudis! Sooooo beautiful. I wish I’d been ablet to do an “extreme science” on them for the kids…they are so beautiful, and so unique, with their lovely “feathers.” The egg shot is unique…never seen that in all my image searches, with such great detail, too.

    Catfish always seem to convey so much “personality”….I’ve loved the ones I’ve had in aquariums throughout my life. That river of Striped Cats is awesome…must have been amazing to see it moving.


  2. MadDog Says:

    We watched that river of catfish for about twenty minutes. It was amazing. In 2,000+ dives I’ve seen it only once. It’s like a “march of the crabs” thing.

  3. Jess Says:

    Hey there,

    Just stumbled upon your site and was reading that you use a Canon G10. I have the same camera with a Fisheye housing and wide angle lens. I really love it b/c it takes good pictures easily and gives me the versatility of manual settings without being huge and bulky like a DSLR.
    I was wondering, though if you have a wide angle lens and if you have trouble with zooming when it’s on? Mine will say “lens error” and turn off. ??? any insight would be appreciated. Nice nudibranchs shots! They’re one of my new favorite critters. is a great resource for id, btw.


  4. MadDog Says:

    Jess, I’ve had a G9, a G10 and now a G11. I have used the standard factory housing for all of them. The super-wide “fish eye” features of some housing and lens combinations are useless without auxiliary flash units. Since I never use flash unless it is unavoidable, I’ve never cared about wide angle. I do mostly macro work for my serious shots and the G series with the factory housing is about the best you can do for macro work in that price range, I think. I would like to have a separate flash unit for modelling, but I don’t want it bad enough to spend the money. Most of them are as expensive as the camera itself.

    The G series in the factory housing will begin to lose the light from the bottom of the frame at about 12cm and gets progressively worse as you get closer. The diffuser helps, but not much. Zoom capability is also limited in the macro mode, as you have discovered.

    If I had a lot of money I’d spend thousands and thousands of dollars on UW camera gear. However, for 90% of the shots that I do, the G11 in the factory housing will take just as good a picture.

    I’d guess that the front of your lens is making physical contact with the inside of your housing when you zoom it too far. The G series will give a lens error, I think, if anything interferes with the lens as it moves in and out.

  5. Steven Goodheart Says:

    (I love listening in on all this camera tech talk…some day, I’ll have one of these babies!)

    Btw, Jess, that nudi id site is awesome! Another tool for this science writer’s toolbox!