What Lies Beneath?
May 19th, 2010, 1:53am
Awoken from my warm cocoon by an unbearable pressure in my bladder, my brain fought to return to the comfort of sleep. Losing the battle, moments later I reluctantly steadied myself on the bunk’s frame and swayed in the darkness of the cabin as I struggled to put my clothes on through my stupor. Gripping the door frame, the hallway swayed back and forth like a suspension bridge as I struggled to keep my eyes open in the harsh fluorescent light. Attempting to focus on the singular goal of completing the convoluted path to the toilet injury-free, I slowly scaled the steps of a near-vertical ladder, taking each step in turn with every unpredictable sway of the world.
Passing through another cumbersome door and its foot-high bottom frame, I was finally outside and made a beeline for the first stall. Quickly looking in the mirror, disheveled hair and bleary-eyed, I’d never seen my eyes so bloodshot. As the boat tipped back and forth in the waves, the water sometimes spilling onto the rear deck loaded with our scuba gear, I finally relaxed.
Relief.
Nothing had ever felt this good.
Tomorrow evening, don’t go over the top with the water, I chided myself. Just drink lots in the morning instead.
Urgent business taken care of, I retraced my steps and was particularly circumspect around the ladder and its thin, sharp metal steps. They reminded me of the uncovered marble steps at our home in Spain as a child. It was usually while running up the stairs that I had multiple painful run-ins as my shins smashed into the unforgiving stone in a moment of childhood carelessness. There was no running this time, but the swaying of the boat was a brand new dimension. I descended gingerly. Lying in my bunk once again, shins intact, the rocking of the boat tossed me back into a deep, dreamless sleep.
The ocean is incomprehensibly vast. Its immense lateral bounds dwarf the continents that we call home, and its depths multiply its domain many times over. Although birds challenge land-based animals’ confinement to two dimensions, life in the ocean truly inhabits all depths, from the shallows of coral reefs, dependent on direct sunlight, to the deepest trench, tens of thousands of feet below the surface embedded in an impenetrable darkness. From the largest animal on Earth, the blue whale, to the tiny krill that it depends on for food, a staggering range of creatures inhabit the ocean. Each species is highly adapted to a specific envelope of conditions, some migrating thousands of miles every year, others remaining nearly static, thriving in the seemingly caustic and inhospitable environment of scalding volcanic vents on the ocean floor.
The senses we possess are woefully inadequate when it comes to surveying this alien world. An analogy I once read described our primitive forays into the ocean as follows. Imagine that at a certain point on land, a vast, uniform wall of fog existed, extending vertically and horizontally as far as the eye could see. Unable to cross this inhospitable boundary, and unable to see more than a few tens of feet into it, strange life forms would visibly flit about the surface of this boundary, shrouded in dense fog. Occasionally a large, shadowy creature would be seen briefly, and then disappear as quickly as it appeared back into the murk. The foreign animals are somehow able to navigate this hazy environment across vast distances and many can detect prey with precision through an exotic sixth sense of bioelectrical signals. A few have developed complex forms of communication. Others possess the ability to produce their own light. This is our mysterious ocean: the largest and most ancient habitat on the planet.
Ironic for a species that has repeatedly ranged over the surface of the Moon, vast unexplored expanses of the ocean remain here on Earth. Most of these areas exist far below the reach of our sun’s light beyond the bathypelagic zone in depths exceeding 1,000 meters or 3,300 feet below the surface. The difficulties inherent to manned exploration at these extreme depths and pressures aside, even unmanned vehicles face the challenge that, mirroring our own bodies, our technology is also designed with the limitations and assumptions of a gaseous environment. We grope blindly through the fog, struggling to adapt to its unfamiliar world long enough to capture glimpses of understanding.
SCUBA (Self-Contained Underwater Breathing Apparatus) equipment allows divers to temporarily immerse themselves in this environment. With no connection to the surface, a simple mechanical system attached to a tank supplies the user with compressed air suitable to their particular depth. Two regulators accomplish this, one worn in the diver’s mouth. The diver simply breathes normally and a wetsuit helps to retain body heat. Though barely scratching the surface at a maximum depth of 40 meters or 130 feet, the world’s reef systems lie comfortably within this scuba diving range, exposing an amazing range of biodiversity to anyone willing to invest the moderate effort in obtaining a diving certification.
Tropical reef systems abound with life, a kind of underwater rainforest. An essential component of the global carbon cycle, coral is a living creature, often locked in a symbiotic agreement with a particular photosynthetic algae, that builds a protective shell around itself made of calcium carbonate. This is the same material that forms sea shells, and the primary component of white sandy beaches that tourists seek. After millions of years this same material is often found on land as limestone. Even mild acidity (for example, that of acid rain) is sufficient to dissolve limestone and release carbon dioxide into the atmosphere that was captured millions of years ago by a prehistoric reef system. The cycle continues.
There are hundreds of different types of coral, and growing together to form a reef system, a dense habitat with endless nooks and crannies is built that provide areas for nesting and protection from predators. Entire islands, known as atolls, owe their existence to these huge colonies of tiny coral polyps, constantly growing their hard skeletons. The coral reef is largely the domain of smaller fish, anemones, shrimp, and eels. Larger predators such as rays, sharks and pelagic fish will roam on the outer bounds of the reef, seemingly aloof, choosing their prey carefully.
A large proportion of people I talk to react with horror to the thought of diving. Part of this I think is an understandable and natural aversion to an environment that our bodies are not designed for. Breathing underwater already sounds oxymoronic before you even consider a worst case scenario such as your air supply running out or that you have no way of speaking. (“In space no one can hear you scream.” Nor underwater.) I get the impression that the remainder of the fear is driven by the unknown creatures of the ocean and Discovery Channel’s annual Shark Week. I shared these same fears before my first ocean dives.
The truth is that diving underwater is incredibly peaceful. Most people can handle the straightforward mechanics and procedures of handling scuba equipment and once comfortable, you begin to realize that virtually everything underwater is either scared of you, ignores you entirely, or curiously and harmlessly observes you. Nothing likes being touched, and nothing touches you. You can slowly drift through a school of fish and they will part to make way for you. It’s largely a matter of size. Few sea creatures are bigger than you and when they are, aside from counting yourself lucky to see such a rare animal in the first place, you are not a recognized form of prey.
Calmly drifting along the reef, you’ll see schools of small fish dart in and out of coral. Clownfish retreat to the safety of their home anemone as you float by and cleaner shrimp advertise their services with their red-and-white banded claws, tucked upside-down in a crevice. Eels patiently wait for their prey to come into range, their heads poking out from between the coral, mouth agape. A one-hundred-year-old giant clam filters the water for food and you hear the crunching sound as a parrotfish scrapes at dead or weakened coral. Rays search for prey amongst a sandy bottom. Bar jacks swim through your exhaled bubbles, and you spot the occasional shark in the distance, timidly curious to know what you are before disappearing into the deep royal blue of the open water, enveloped by the fog once again.
Surprisingly, as my father observed one day, you rarely see any hunting taking place underwater. The larger fish never seem to eat any of the smaller ones. I thought about it for a moment, and on over 75 dives, I agreed that I’d never seen a single fish get eaten. My experience would dramatically change that night.
