Shots Below with Nikon D70:

I swam over a small coral island surrounded by sand. It is a section I visit often and there was a strange block of green (sponge?) that just didn't fit with the scene. I dove down to investigate and saw it move.

I could see that there was a large crab under it and that it was attached to the crab's shell. I couldn't coax the crab to climb out and be seen with my fingers gently probing so I swam off. I found a half of an oyster shell that I figured I could slip in between the crab and coral without doing any damage and perhaps get the crab to move into a better view. It proceeded to hop off the coral and down into the sand. I followed it around with my camera as it sought various means of hiding and alluding me. A couple times it came forth abruptly with both claws out and snapping at the camera.

I felt I got some shots so I left the crab and swam on. It seems to have a very effective disguise going for it and I pity the prey who catch its interest as they cross its path! I did a google on Hawaiian crabs and found out that this guy is a Sponge Crab and certainly he is sporting his namesake well.

I had planned to keep this series open to additional shots taken with the Nikon and doubted very much I would encounter a spong crab again. As luck would have it, I was swimming in the same area today with the Olympus hanging from my neck when I spotted a group of legs in the sand surrounded by some coral:

In no time, I was able to discern that I was seeing a pair of spong crabs in some form of imbrace. I assume it might have been intimate in nature and for that reason, I didn't disturb the pair beyond swimming down and taking a number of shots with the Olympus. I watched them for probably 10 minutes and there was little movement beyond some rocking forward and back and some slight changes in position. The one crab (on the left above) has large claws out and embracing the other crab. It would vary in how much it was over and above the other crab. At one point they disengaged and the underneath crab tilted over on one side before again getting underneath the other crab. The positions of their sponges would alter from being towards the back to more over the top. The crab on the right has a wreath shapped sponge that brought to mind a pillow of sorts...

I am now more optimistic that I may see these critters again and I look forward to the possibility.