Total Immersion

Total Immersion

After a full day in transit yesterday continuing our journey to the northwest, we awoke this morning at Maro Reef (Nalukākala). Unlike most of the Northwestern Hawaiian Islands, Maro has no permanent emergent land, it’s only exposed sandy patch can be submerged at high tide. We’ve made a few dives at this location before, but our experience suggests that the water is often murky, and the deep habitats somewhat … uninspiring. Alas, our dives today further corroborated the latter (the drop-sites on both dives consisted of vast expanses of sand, and not a whole lot else).

NOAA divers Randall Kosaki (right) and Jason Leonard (left) swim out across the sand at a depth of 270 feet at Maro Reef.

However, even barren sandy bottoms can reveal interesting things. After swimming for about 15 minutes over sandy nothingness on the bottom, we came across a tiny oasis in the form of a Sand Anemone (Heteractis malu) serving as a refuge for a group of juvenile Hawaiian Dascyllus (Dascyllus albisella) and a juvenile razor wrasse (Iniistius aneitensis).

A Sand Anemone (Heteractis malu) serves as a refuge for a group of juvenile Hawaiian Dascyllus (Dascyllus albisella) and a juvenile razor wrasse (Iniistius aneitensis).

After 25 minutes on the bottom, we came across another interesting thing: a pair of Blue-spotted Urchins (Astropyga radiata) cruising along the sandy bottom 200 feet (60 m) deep. I’d never seen anything like them before, and neither had Randy, so he tried to collect one in a zip-lock bag while I filmed him (and laughed every time he poked his finger on one of the urchin’s spines). Then I gave it a try, and heard Randy laugh every time I poked my finger on the urchin’s spines! I eventually managed to get one of them into the bag.

A pair of Blue-spotted Urchins (Astropyga radiata) cruise along the sandy bottom 200 feet deep at Maro Reef.

As a bonus, the Urchin also came with a small fish hiding among the spines. Once we managed to separate it from the Urchin and got a good look at it, we weren’t entirely sure what species it is. At the moment, we believe it may be a post-larval Hawaiian Grouper (Hyporthodus quernus), but we’re not completely sure. When we get back we’ll be able to make a more definitive determination.

A post-larval fish, possibly a Hawaiian Grouper (Hyporthodus quernus), was found hiding among the spines of an urchin at a depth of 200 feet at Maro Reef.

Several days ago I mentioned that I tested out a special 360-degree camera system at French Frigate Shoals. I had promised to report more on that experience the following day, but between the non-stop barrage of things that need to get done on this cruise, and the fact that I’m still learning how to stitch the omnidirectional video together, I haven’t had time to follow up. Today was the second test of the system, and so far it seems like it was a HUGE success!

A group of sharks inspect a GoPro ominidirectional camera system off Maro Reef.

During decompression, we were joined by about fifty Galapagos sharks, and they spent most of the decompression time swimming around and among us. The topside crew lowered the camera after I sent a signal to the surface, and it seemed to work perfectly. Of course, we won’t know for sure until we process the six video clips and stitch them together. Watch this space!