Thursday, October 25, 2007

Just Another Day In The Grotto

This nudibranch is called a Halgerda johnsonorum, and this was only the second time I've ever seen one, so I was quite excited when I saw him just sitting in the wide open on a rock. This is the same species that I caught mating with the Halgerda guahan a little over a month ago. This one is definitely a more rare find than the guahan or the malesso, at least in the Grotto. In the picture above he is in his "sitting" pose, kind of all scrunched up, making him look more round and short. Luckily for me he decided to go for a stroll and stretch out, giving me the ability to get some different shots. Here he is on the move and is fully stretched out. I think it's cool the way they can appear either totally flat, or they can raise the surface of their body along the yellow ridge lines. I don't know if they do that as a defense mechanism or it's just the way they are. Since this was only the second time I'd ever seen this guy, I was taking a ton of pictures, probably close to 150 just on him alone. Some Japanese divers had come in by this point, and were curious about what I found so interesting. The two tourists both had cameras, so I motioned them over and pointed out this guy, and the Halgerda guahan who was only a couple feet away. The lady got so excited you could actually hear her yelling underwater. I always enjoy sharing my discoveries with diving tourists, as I'm sure they love taking the pictures back with them. As I was swimming through the Grotto looking for the next nudibranch, I ran across this egg mass. A year ago I would have had no clue what it was, and frankly wouldn't really have cared. Now that I have started my educational process with the nudibranchs, I have seen enough egg masses and ribbons to realize that's what this is. The thing about this one that throws me for a loop is that I've never seen another one like it. I've shown you pictures of the egg ribbons of the Halgerda guahan and malesso, they are the tan ones that look like a strip of something glued to the rock in a spiral pattern. This one was a tube, but if you blow the picture up and look closely, you can clearly see the little strings of eggs. I have learned from the Philinopsis gardineri that they will wrap these egg masses around their bodies, and then they shed them as they move forward, leaving a cocoon like contraption. So now the question is, what kind of nudibranch leaves this kind of egg mass? You can bet I'll be looking until I figure it out. Then as I got back up to the rock where I find all the purple Ptereolidia ianthina, I spotted these two Halgerda guahan, each partially in little holes on the rock. That would be why some days you can look and look and maybe only find one or two in all of the Grotto, they are hiding out in their holes. And because their body is completely flexible and moldable, they can fit in just about any kind of hole or crack. After looking around for a bit I found this about 4 feet below where these two were hanging out. This is the egg ribbon for the Halgerda guahan. You can see all those little holes in the ribbon, that's what happens to the lighter spots I showed you a couple days ago. So are those spots where the eggs have already hatched? Just one more of the many mysteries begging me to figure them out. And then I had to take a few pictures of the Ptereolidia ianthina so they wouldn't all be screaming discrimination. They seem to get a little jealous when you pay too much attention to the other nudibranchs, and they won't look at you when you try to take their pictures. So in order to keep everything in balance in the world of Grotto nudibranchs I did the right thing and took a few pictures of this guy too. And the best part of a dive like this is that it's not unusual, I can go down to the Grotto pretty much anytime now and come away with as many nudibranch pictures as my memory card can hold. Yes, I'm spoiled rotten, I'll readily admit it.