“It’s Arctic Down There!”

Somewhere out there on the internet is a video of a couple of guys doing a deep dive at Christmas Island (Line Islands), whereon they encounter a rather abrupt thermocline (sudden change in water temperature) on their way down to over 400 feet (120 meters). Today’s dive was a bit of déjà vu for those same couple of guys (along with Rob and Sonia) — both thermally and audibly. As we descended past about 290 feet (88 meters) down the drop-off on the westernmost end of Pohnpei’s barrier reef, the water was suddenly very cold. Brian and Sonia toughed it out and spent a fair bit of time down in the range of 330-355 feet (100-105 meters), but Rob and I decided that there was plenty of interesting things to see just above the thermocline, so after a brief excursion down to the icey depths, we ascended out of the deep freeze and remained at about 280 feet (85 meters). Whereas Sonia was clad head-to-toe in a neoprene wetsuit, Brian had opted for the T-shirt and swim shorts approach of one of his long-time dive buddies (err… that would be me). Brian’s determination paid off, however — in addition to several rare wrasses, he collected what appears to be a new species in the genus Parapercis (sand perch). I’ll leave it to Brian to post more details on his ichthyological treasures.

Rob and I had a splendid (and somewhat less chilly) dive, drifting slowly along the drop-off in a zone that had some small horizontal caves and undercuts, which appear to be remnants of an ancient shoreline. We encountered a pair of Griffis‘ Angelfish (Apolemichthys griffisi) — a relatively rare species that Randall Kosaki and I first observed here in 1989, but to our knowledge has not been recorded from here since. We also saw many of the same species as yesterday (including the undescribed Chromis and Pseudanthias), as well as a few others such as the White-barred wrasse (Pseudocheilinus ocellatus). I also think that I might have caught a glimpse on my all-time favorite fish, Pyle‘s Soapfish (Belonoperca pylei), but I can’t be certain (it might have been a basslet in the genus Liopropoma, which can look similar). Unfortunately, after descending into the deep freeze and returning to the somewhat warmer shallow depths, the port on my video camera housing fogged over with condensation, ending my ability to capture video for the next hour or so.

We were joined by Dave, Josh, Richard C. and Garrett on the decompression phase of the dive, which was relaxing and uneventful (not to mention blissfully warm!), and we all surfaced after nearly three and a half hours in the water. We are now finished with our “work-up” dives for this trip, so tomorrow we begin our deep exploration in earnest (although these past two dives have certainly qualified as exploratory in nature!). Each day we’re getting an earlier start (which we need to do, in order to conduct longer dives) — in part because we’ve finished all the initial set-up logistics, and in part because we’re getting into a rhythm.

My apologies for the lack of photos on this post. As it turns out, my camera was stuck in manual focus mode for the whole dive, and as such, none of the footage is usable (or frame-grab-able). I’ll definitely be more careful about this tomorrow!

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