It's about diving. And cats.

Me diving

Saturday, August 30, 2014

Cordell Practice Dives

Rockfish at Eric's Pinnacle
Photo by Clinton Bauder
 We were scheduled to dive on Saturday on a tech boat, but the forecast was looking pretty terrible as we approached the weekend.  So, with the high likelihood that we were going to end up diving in the bay, we decided to convert the boat to a practice dive for Cordell instead.  For this year's trip to Cordell, we are planning to set the stage to start a multi-year transect-based photographic survey of a site.  So, that requires setting up permanent markers (for which we were thinking of using lead fishing balls) to leave there to re-locate the site in future years, then running transect lines between the markers, and then running along the lines with a scale stick, and taking meter-sized pictures along the line.  So, obviously, a practice session (or three) was in order.

Me with a scale stick thingy
Photo by Clinton Bauder
We were originally discussing doing this at Kawika's, but decided that we wanted more topography, since that would be trickier and more realistic for the site we had in mind at Cordell (or actually the site that the Sanctuary people had it in mind).  So we eventually settled on Aumentos, as the best site in terms of topography, which was also diveable in the day's conditions (which were not good).  We came  up with the plan for the dive, which not too surprisingly, was insanely complicated and seemed unlikely to actually be pulled off once we were underwater.  The boat dropped the balls on two different lines, so we would descend one line and find the second one, then scout the site and move the balls into a triangular formation, run transect lines, and take some sample photos.  Then at the end, we'd move the balls back, clip them back to the lines, and the boat crew would pull them after we surfaced.  We did not have our full complement of lift bags yet, just one to share.  So we had to serialize the ball moving, which clearly would not be ideal for the real project.  But we took turns so that everyone got a try with various skills.  Rob and Clinton were taking pictures, and I got a little bit of video.  I was also manning a scale stick, and was paired up with Rob for one pass over the transect lines with him taking photos.

Matt and Rob moving a transect anchor
Photo by Clinton Bauder
The viz was really really good for the site, which definitely made things easier.  Finding the second line with the extra balls was trivial, and we could see the down line from the spot that we picked for the transect.  So basically everyone could see everyone throughout the whole dive, which made it quite easy to coordinate everything.  I mostly just watched in the beginning, while others were placing balls, and took a little video.  Then I escorted Rob while he moved one of the balls, and then once the first transect line was laid, we swam along the transect line and I held the scale stick along the line.  It was kind of difficult to figure out how exactly to orient the scale stick along the line, so one takeaway was that a quadrat would probably work better.  We also do a bit of video along the transect line, just to see how that worked.  After several passes over the lines, with both Rob and Clinton taking pictures, we cleaned things up, moved the balls back over to the downlines, clipped everything off, and started our ascent.  While we were on the line, we saw a bat ray swim by!  It's been a really long time since I've seen a bat ray around here, so that was pretty cool.

John and Matt setting up transect tape
Photo by Clinton Bauder
We finished up the first dive pretty quickly, and since the viz was so awesome, we decided to do a second dive, and went to Eric's Pinnacle.  Rob didn't dive for some reason -- I think he got wet on the first dive, but he also likes to claim he's never dived Eric's Pinnacle (even though that's not exactly true).  So it was just me and Kevin in my team for dive two.  On the way down the line, my ears were not cooperating.  I couldn't seem to get below 30 feet, but eventually I just swam over to the pinnacle at 30 feet, and hung out there for a bit, until my ears very slowly allowed me to go deeper.  Eventually we did make it to the bottom.  We circumnavigated the pinnacle and then worked our way up.  The viz was excellent, and we saw the usual assortment of Eric's critters.  There was a nice-sized school of rockfish hanging around by the pinnacle.  I eventually called the dive because my ears were continuing to bother me.

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