We are wrapping up the first half of the midwater research leg tonight. The RV Western Flyer is bound for La Paz, and tomorrow we will begin a two-day port call that will allow us to make personnel changes in the ship's crew, the ROV pilots, and the science team. Likewise, we will acquire some replacement parts for the things we broke, re-supply the stuff we used up, and take some long, long showers.
During today's dive, we surveyed the water
column, trying to establish the depth ranges of the principal members of
the midwater community here. While we survey, we keep a close watch on the
readout from ROV Tiburon's
oxygen sensor because we believe that in many cases it will be oxygen that
is the determining factor. Sometimes we fly a straight and steady path,
sometimes a vertical profile, and sometimes a stair-step pattern. We
identify and count the animals we see, often stopping for video frame
grabs or to spend some time identifying something new.
We tend to think that the world we see
through our cameras is the real midwater world, and in one sense of
course, it is. But we also have to remind ourselves that our presence
surely imparts a strong bias to what we see and to what we don't see. We
try to remember that what we're doing is sort of like driving an
18-wheeler through the forest at night, with all the lights on and the air
horn blowing, and wondering where all the squirrels are.
Later in the dive, we worked just above the
smooth bottom at about 2,800 meters, counting spiders for Karen
Osborn, measuring bioluminescence for Edie
Widder, and identifying fishes for Jeff
Drazen. This leg of the Gulf Expedition incorporates seven distinct
research projects, and it's tricky sometimes to keep everyone supplied
with samples, ship time, lab space, and Tiburon time. When things
get tense, it helps to be able to laugh at ourselves, and today we did it
Three unknown critters (on the left) racing through a grove of sea pens as Tiburon follows and a whole 'herd' of them on the right.
Our attention was concentrated on some
small benthic animals just in front of Tiburon when something raced
out from underneath us tailing an enormous cloud of suspended sediment.
"What the hell was that?" Then there was another one, and
another. We looked at each other, then back at the screen. "What the
hell are those things? Let's go! Go!" We chased them, careful to stay
close to the bottom in order to keep them in sight amid the growing cloud
of rolling sediment that looked like a smoke screen.
"They're skates," said one of us.
"They're crabs," said another. "They
look like cartoons of the Road Runner zipping across the desert,"
opined a third. We raced along above them trying to get a look at what
they were, but all we could catch were glimpses of the leading edge.
Everything else was enveloped in the swirling dust. Sometimes there were
lots of them, sometimes only a few. But when they stopped, they were lost
to view as we flew ahead, above the leaders, trying to see. Finally, two
of them darted out to the right of the cloud and settled out in the clear
as we pounced on them for a look. "They're... rocks."
what happened. We were descending a slope steep enough for rocks to slide
and roll down but too gentle to be obvious to the camera. As we worked
downslope, Tiburon's tail bumped the bottom, dislodging rocks and
sending them racing downhill in a tremendous cloud of dust. It was a lot
of fun getting so excited, and in the end, we all had a good laugh,
especially the pilots who had seen this before. But it points out how
valuable it can be to have 3-dimensional vision. Had we been down there
ourselves we would have seen the slope immediately and not been fooled.
In 1940, as John Steinbeck and Ed Ricketts
approached Guaymas for their first call at a port that was linked to
the world outside the Gulf, they wrote: "The world and the war had
become remote to us; all the immediacies of our usual lives had slowed up.
Far from welcoming a return, we rather resented going back to
newspapers... We had been drifting in some kind of dual world—a parallel
realistic world; and the preoccupations of the world we came from, which
are considered realistic, were to us filled with mental mirage."
Such feelings are common after being at sea
for a while, especially when you are immersed in exploring a deep
region that no one has ever seen before. As we head for La Paz tonight, I
think that many of us regret that tomorrow morning we will wake up in that
other real world. We will pick up the sea stories again in a couple of