Dive Odyssey (Part Two)

Coral Sea memories,continued.  Organized by topic.

Breathing.  

Always one of those things we divers have to take seriously.

It has to be admitted, right off, that my air consumption sort of sucks.  I use up a tank of air quicker than I should— not crucially, horribly, but quickly enough so that it bothers me.

It’s hard to say why, except that it started on my previous dive trip, to Pelau.  At the time I was suffering from an undiagnosed case of acid reflux, so I’d figured my pulmonary efficiency was impaired by breathing stomach acid.  But I’ve got meds for the reflux now, and my air consumption is still high.

You could put it down to nervousness, but I’m an experienced diver and I’m perfectly relaxed underwater— more relaxed than I am on land, generally.  I use zen breathing and take long, long breaths, which you can do if you’re breathing air at, say, three atmospheres and there are three times the oxygen atoms per square inch.  I am a good deal more muscular than the average guy, and muscles need O2, and of course I’m older than I used to be.  But still, it’s a puzzlement, and it stinks.

One thing I discovered was that we need more hand signals for air status.  Right now there’s a sign for “I’ve used up half my air,” and another for “My air will go critical in a bit, gotta surface now.”

I’d like to add some signs for “I’m two-thirds down,” and “I’m getting a little low, but there’s no reason for concern,” and “I’m a little lower, and if I were the sort of person to be concerned about this sort of thing, I might think about thinking about being concerned, maybe.”

(And by the way, Australians seem to have a lot more hand signals than I’m used to.  At one point, I could have sworn I received the signal, “You two buddy up and stay here, while I nip ’round the corner and buy a very large hat.)

Also, I was diving with American gear, which records my air supply in psi, and everyone else was reading their gauges in baryes, which is a metric measurement that I don’t understand.  (I think it’s 1/2 hectare x # of coulombs divided by the square root of the candela.)

This was my first dive trip using Nitrox, which is a breathing mixture with a higher percentage of O2— usually 32% as opposed to 21%, the rest of the fill being nitrogen, without the trace gases present in air.  I was hoping to get more bottom time per air cylinder, but that didn’t work out— each cylinder lasted about the same time on both air and Nitrox.

What actually made Nitrox worth while was that I didn’t get as tired as I normally would— I was a bundle of energy the whole time, except when the compressor for delivering Nitrox broke for 24 hours or so, and I had to go back to air . , , and suddenly acquired the impulse to nap after each dive.  When I went back on Nitrox, my energy levels soared.  So it’s Nitrox from now on, hurrah!

The Long-Suffering Dive Buddy.  I was alone on the trip, so I didn’t come with a dive buddy pre-installed.  Guided dives were an option, so for the first couple days I took these.  The guides knew the area better and knew where all the cool stuff was, but I got tired of jostling around in a crowd.

About this time Scott and I buddied up.  He was from British Columbia, about my age, and a newcomer to diving— in fact he’d done only five dives before his arrival, and none in salt water.  But he was calm and level-headed, and adjusted very well, and what’s more his air consumption was roughly on a par with mine.

Unfortunately he had to put up with my navigation, which was not always on the money.  There were a few times when the dive plan went awry and I had to quietly surface to take a bearing on the boat.  But we only got swept away once, and I maintain that wasn’t at all my fault.

Swept Away.

This was at a dive site called Acropolis.  There was a strong current, a grey sky, a strong wind, and an uneasy sea.   The dive site didn’t look at all inviting.  Once we got under the surface, the water was dark and flying sand made the visibility poor.

Scott and I planned to kick into the current at 60 feet till our air was half gone, then rise to 40 feet and drift back to the boat.  The first half of the dive went well, but as we reached the turnaround point I realized we were zooming along with the current instead of kicking into it.  So it was more effort to reverse course than I would have liked, and as it happens the reef looked totally different at 40 feet than it had at sixty.  Eventually we were completely lost and running low on air, so we did our 3-minute safety stop on top of the reef, and then I surfaced to find out where the boat was.

I came up about 100 yards off the boat’s starboard quarter, so I took a compass bearing on the boat, dove to where Scott waited for me, and started kicking along that compass bearing.  By and by I realized that we should have passed under the boat by now, so I came up again, only to find that we were now 200 yards off the boat’s stern.  The current had just torn us away from where we needed to go.

(Mind you, Scott had a different explanation for why we ended up where we did.  He thought we crossed to the far side of the reef and came up there.)

I was pretty much out of air, so I inflated my BC, rolled onto my back, and started kicking for the boat.  Despite the current I probably would have made it, but as it happens the watch on the boat saw me, and the Very Tall First Mate roared out in a Zodiac to pick me up.   I did okay getting into the boat, but a wave took the boat out from under me and I fell heavily into the boat’s bottom, scraping my knee.  Scott surfaced once I was aboard, and came aboard the Zodiac as well.

What made this less embarrassing was that four other divers had to be picked up as well, one of them a guide.  (Though of course the guide might have just been keeping an exhausted diver company, which after all was his job.)

Altogether, a fine example of how a well-planned dive can go pear-shaped.

Camera

I’d equipped myself with a SeaLife camera, a low-budget alternative to the $5000 or so a really first-rate underwater setup would cost.  The SeaLife is basically a pocket digital camera in a waterproof box, with “piano key” controls that make it easy to operate underwater.

The SeaLife has some nifty features.  It takes video as well as still photos.  And it has a “diver” setting, which adds a dollop of red color to the camera’s output to compensate for the fact that the sea is soaking the color up.  (Photoshop can’t add red if it’s not there to begin with, so this is useful.)

The SeaLife’s disadvantage is that its little electronic brain is very slow, and that fish are very fast.  Often there was a two- or three-second delay between my pressing the shutter button and the picture being snapped, by which time the subject of the photo had vanished, turned sideways, or hidden behind a lump of coral.

My photos and videos were at the beginning fairly wretched, but as the week went on and I got used to the camera, I got some nice pics.  Still, most of the best pictures are of non-moving coral formations, as opposed to fast-moving fish.

Shark Frenzy

I’m thinking dive companies are more or less obliged to do these.  We had to sign an extra waiver to do the shark encounter, on top of the extremely comprehensive waiver we had to sign to get on the boat in the first place.  (I think somewhere in those clauses we absolved Mike Ball in the event of an attack by Godzilla.)

We went down to a natural amphitheater and found the sharks already there— they knew better than we did what was about to happen.  We just sat around while more and more sharks gathered and while Kirren did the work, hauling a sort of garbage can down to the reef.  It was full of tuna heads chained together, with a buoy to pop the the chain out when the lid was released.

By the time the lid came off, there were 30-40 sharks swimming around, grey sharks and white-tip reef sharks and maybe an epaulet shark or two, as well as jacks and some smaller species that I’d think sharks would normally eat.  They were perfectly safe, because the sharks’ focus was elsewhere.

It was a lot of buildup to maybe 20 seconds of action.  The buoy never even fully deployed, because the sharks were hitting it about a half-second after the lid came off.  The tuna heads didn’t last long, and once they were gone, the sharks wandered back to their lives.

I found myself in an unplanned shark encounter late, as I was returning from a night dive.  The boat’s floodlights had attracted a swarm of baitfish, and the baitfish had attracted a lot of sharks, which I noticed as I was returning to the boat.  Lots and lots of them zooming around.  But they were silvertips, and smaller than me, and I didn’t feel threatened, for all that I kept an eye out.  I was out of air and had to come up,  and that’s what I did.

“We watched you coming,” I was told shortly after.  “We were really interested.”

It was interesting watching the sharks from the safety of the boat.  There’d be a whirr as one of the baitfish was driven to skitter along the surface, and then a shark would rise and just fall on it, smashing it with its full weight before gobbling it up.  I hadn’t realized how physical a shark attack is.

Barbecue.

A couple nights the Very Tall First Mate set up a grill and grilled some shrimp, beef, pork, and kangaroo.  (The roo was sweet-tasting and not at all bad.)

I asked, “Is it possible to eat grilled shrimp in Australia and not think of Paul Hogan?”

“No,” I was told firmly.

Other Cool Stuff.

On our final night dive we were accompanies by a whole herd of swift-running jacks, which by the way are a sizable, aggressive, silver predator fish.  They were always packed into the beam of our dive light, and I thought at first that we were herding them somehow.  And then I realized that they’d learned that dive lights picked out smaller fish that they could eat, and so they’d learned to hang around night divers in hopes of an extra-tasty snack.  After that I kept my light beam bouncing around too fast for them to fasten on any prey.

Unicorn fish, with their single horn.  A snapper that looked like a black-and-white version of an American flag.  Zebra-striped fish.  Huge, calm schools of sweetlips and one-stripe snappers.  Napoleon wrasse, with a jaunty cocked hat on their heads.

Nemo.  Nemo, Nemo, Nemo.

My polyglot fellow divers.  Japanese, French, Swiss, Korean, Hungarians, Aussies, Canadians, and a few Americans.  A Russian who shaved his chest hair and wore Speedos.

Excellent wine.  (Thank you, Cleo.)  Sad, cheap beer.  Johnnie Walker.  Digestive biscuits.  The Southern Cross.

Thank you, Mike Ball.  It was unforgettable.