The Gold Lace Nudibranch at Kahalu'u

    Saturday began as it always does.  With the green waste depository open only three days a week, Saturday being one of them, the day started with hacking the dead leaves off the banana trees and pruning a kukui nut tree away from the White Tree of Gondor.  Sandra emerged from her boudoir around 7:00 AM and we segued in to the pièce de résistance: pruning off the top five feet  of our avocado

Gold Lace Nudibranch,Halgerda terramtuentis. Kahaluu  October 2020

tree.  The point of the cut was twenty feet up in the air and four inches thick.  Suffice it to say, by the time we were done with that little endeavor I was bushed.  

     Even at my advanced age I was able to rally.  After we dispensed with our sundry leaves and branches we drove back south to Kahalu'u. Although it was still early, there was a surprising number of swimmers out in the bay.  I counted eight, which for K Bay during the time of the pandemic, that may be a record.  The tide was high, so getting out was easy.  And the water was cool and clear, so all we needed was for something interesting to come along.  

    I swam over to the breakwater, seeing just a few fish, and then turned around and headed for the middle.  Just as I made the turn, in a bowl about six feet across, created by three modest corals clinging to life, there was something small and fleshy washing back and forth.  Essentially oval, and possibly an inch or two, it at least merited investigation.  It took only a couple dives to discern that, as it rolled over,

Gold Lace Nudibranch floating

it possessed a foot.  Another dive or two and I could identify rhinophores and gills.  This was a wayward nudibranch, possibly washed in from somewhere outside, but still essentially intact!

    At the end of the blog I am including a short movie so you can see what I saw and ask yourself, "Would I stop and look at that little lump?"

   I spent the next ten to fifteen minutes diving down, hanging on and taking pictures with a variety of settings, hoping for something in focus, with enough light and with our tiny sea slug in the correct posture to display his features.  During most of this time, he was washing back and forth, tumbling slowly over and over.  Me and the camera had our work cut out for us. 

   At one point the nudibranch was washed near the surface and I cradled it in my gloved hand, managing to take a picture before it was washed away.  This picture is not too bad, and shows that the nudibranch was smaller that I thought, more on the order of an inch at the longest dimension.  

    Towards the end of my effort, the nudibranch wedged between a piece of rubble and a coral.  He may have responded to this bit of serendipity by actively attaching himself, but this was hard to tell.  Regardless, my last few dives involved attempts at a relatively stationary organism. 

Gold Lace Nudibranch, floating ventral surface

   Back in the shelter, Sandra and I looked through the multitude of pictures and movies I had taken.  As you can see, there are a few that are pretty good.  In one frame, the camera caught the nudibranch floating with the light shining  through, all in focus.  One has to consider all the things the camera might choose to focus on to appreciate the luck. We could clearly make out the black and white gills and rhinophores. 

   At home, we found his picture in John Hoover's Sea Creatures.  This is the Gold Lace Nudibranch, Halgerda terramtuentis.  John says it is found between 15 and 100 feet, often in caves.  Divers, who are the author of most such field guides, often say things like that, when they might very well mean from 2 to 100 feet.  They simply don't spend enough time in shallow water to know what is up there. Nevertheless, Kahalu'u is not good nudibranch habitat and it is most likely that this tiny fellow got separated from his home and washed into the bay.

   Sandra and I also checked out Sea Slugs of Hawaii,  the internet bible managed by Cory Pittman and Pauline Fiene.  They have some amazing pictures of this animal, which you will find among the

One more look at the Nefarious GLN

Discodorididae nudibranchs.  My friend Pauline says it lives as shallow as 5 feet and in rocky areas, so I suppose it is possible that this individual might live in the bay.   

   As we were rapping up our effort, Sandra looked at our good friend Peter's blog and found his post from about a year ago.  He and Marla encountered a Gold Lace Nudibranch washing free in the water at Mahukona.  Apparently this is one of the more common nudibranchs so we shouldn't be surprised that every now and then one gets dislodged and appears for our enjoyment.  A big part of the trick is to be out there looking around when something wonderful occurs.

jeff