JULY 11 AND 12: WING AND TANKER BARGE
Read MoreCrinoids. The yellow is likely Comanthina schlegeli, the black Comantheria briareus. These are basically just extremely "bushy" sea stars.
Some nice corallamorphs at the bottom of the Canyon. Not sure of species, but likely genus is Discosoma. The name corallamorph basically just means "coral-like," and these are similar to corals in many ways. This would have made a nice wall-paper in the '70's! Even the name ("Disco" soma) sounds like something out of the 70's or 80's!
Nudibranch (Chelidonura inornata). You can see the size on Rose's hand. This species eats flatworms (you will see a flatworm in a later photo).
According to what I have been told, prior to the invasion of Saipan, American forces pulled a large concrete barge ("tanker") into Saipan waters under cover of darkness. They then cut it loose and let it drift. It ran aground at its current resting place. From a safe distance, American ships then watched as the sun came up. As first light arrived, the Japanese saw this new vessel in their lagoon and fired upon it. This allowed the Americans to observe where the major Japanese gun batteries were so that the invasion could be planned with better information.
Some of you have read about these guys in previous albums. If this includes you, please forgive the repetition. A blue dragon starts out life much as does any other nudibranch. It feeds on poisonous hydroids and soft corals. Now, these critters (hydroids and soft corals) contain symbiotic organisms (called Zooxanthellae) which photosynthesize and provide food. They also contain stinging cells (called nematocysts) for protection. The blue dragon digests most of the body parts, but the Zooxanthellae and nematocysts are able to pass through the dragon's digestive tract and become incorporated into the surface tissue. The many appendages (called cerata) are arranged to maximize surface area and allow optimum photosynthesis. Many experts say that blue dragons probably do not need to eat at all once they attain adulthood.
This barge is not really considered to be a dive site, but I think it is totally cool. It has just enough walls, compartments, and windows to create mystery and lead the explorer onward ("What is through THIS window?"), but is open enough to be a reasonably safe open water dive (NOT a penetration type of dive). There are many skylights above, which let the sunshine through, as you can see here.
These little volcanoes occur elsewhere, too, but not usually this densely. I don't know what type of critter creates and lives in these. Sometimes they will "erupt," with sand and small debris coming out for a minute or so. I have tried to dig down, but have always come up empty-handed. If anyone knows what these are, please leave a comment!
I'm not sure what species this ornate nudibranch is. I think it is genus Risbecia, which is a type of Chromodorid. By the way, the term "nudibranch" technically means "naked gills." You can clearly see the gills of these two, on their backs.
Pretty critter. Remember the nudibranch earlier which, I mentioned, eats flatworms? Well, for that nudibranch, here is a tasty, 2-penised morsel! By the way, I'm not sure whether or not the sexes are separate in this genus. They may be hermaphrodites, for all I know. Mixed male and female AND 2 penises. If THAT's true, it must be quite a life!