"Into the Deep"

The six-pack vessel (a small affair -- capacity is six to ten recreational divers, divemaster and captain) pulls to a stop over yet another huge reef structure. We are off the southwest coast of Cozumel, some distance from the island (but still in sight of land) and perhaps 15 miles from mainland Mexico's Yucatan peninsula. At the prompting of our divemaster, we alternately roll backwards into the Cozumel Channel, and begin our descent to the sand bottom. Participants include David (the Mexican-born divemaster), Albert (our American instructor, with over 5000 dives), Wiley (Albert's son, an expert diver), Darren (another excellent instructor), Terry (savvy journeyman) and novices Dar, John, K.C. and myself.

The routine in Cozumel is to motor out to the reef structures, generally on the south end of the island, descend to the sand bottom adjacent to the reefs (usually between 40 and 60 feet) and then swim to the reef to be explored. At least a dozen major reef structures protect this side of the island. A major issue here is the Yucatan Current (read CURRENT) that prevails on most dives. Although occasionally not present, it typically moves northwest at from 1 to 5 knots. At first it is rather frightening to the novice, but after some experience this flow becomes a very pleasant and natural way of approaching the dives at this piquant site in the western Caribbean. As we descend we move "downstream" from the surface vessel. The captain of the boat is altogether as expert as the underwater guide; he is charged with the task of "following the bubbles" as divers ascend (sometimes up to a mile away) later in the dive. His job is further complicated by the notion that divers are of different skill levels, and will therefore use air at variant rates. He must pick us all up as we ascend at different locations above the reef or out over the open ocean.

At least a dozen major reef structures protect this side of the island. A major issue here is the Yucatan Current (read CURRENT) that prevails on most dives.

When we near the sand bottom we are to adjust our buoyancy to neutral. This is perhaps the most important single task of a responsible scuba diver, as neutral buoyancy and a moderate amount of coordination are the most important skills necessary to negotiate the steep high-profile reefs that exist here and in other parts of the world. Adjustment is simple -- add air to your BCD (Buoyancy Control Device -- a sort of inflatable life jacket) to go up, and expel air to go down. With practice this is not difficult, even for the novice. Obviously, skill in buoyancy is also necessary when ascending, so as to not surface too quickly. This faux pas could be fatal, so proper buoyancy control is a critically important skill.

We explore for a few minutes, and then enter the reef and begin a series of "swim-throughs." These openings are not quite caves, but something more than "doorways." We were told of the current and these "swim-throughs" in various pre-dive briefings, but nothing really prepared me for the experience. Earlier I felt as if I would possibly be frightened, even claustrophobic; instead, a deep and profound tranquility overcame me as we entered and swam through these remarkable underwater grottoes.

After proper buoyancy is attained by all the divers, David leads us over to the literally high-profile Santa Rosa Reef. We explore for a few minutes, and then enter the reef and begin a series of "swim-throughs." These openings are not quite caves, but something more than "doorways." We were told of the current and these "swim-throughs" in various pre-dive briefings, but nothing really prepared me for the experience. Earlier I felt as if I would possibly be frightened, even claustrophobic; instead, a deep and profound tranquility overcame me as we entered and swam through these remarkable underwater grottoes. In recent days -- and only after returning from the island -- an understanding of this phenomena has begun to emerge in my conscious state, although at the time I "merely" felt a deep relaxation coupled with a curious feeling of familiarity. Oddly, this "event" can actually be measured: my air consumption (directly read off gauges and computers carried by all divers) actually went down as we descended through the caverns. (It should have gone up as we continued to descend.) I have come to conclude that this feeling of profound serenity had to do with actually being in the womb of a living, breathing organism.

I have come to conclude that this feeling of profound serenity had to do with actually being in the womb of a living, breathing organism.

The structure we were penetrating was "built" over millennia by star coral, an organism that now inhabits the hard, visible outer shell that we observe. When Darwin first described the distribution of tropical coral reefs worldwide, he (and others since) was confounded upon recognizing that the reef seemed to be dominated by animals. Essentially, "how can one of the most flourishing, highly populated biotic communities, the coral reef, survive in almost plankton-free waters of the tropical seas?" Where are the plants? Essentially, the coral animals are not at the base level of the trophic pyramid (biologist's pyramid of life -- topside always dominated by plants on its base) of the tropical coral reef. The plants, in an remarkably mutual and much more than symbiotic relationship with the coral polyps, live within the coral animal; the two organisms act as one and essentially consume one another's excess food production and waste. All relationships on the reef possess this sort of special mutualism, so complex and intertwined that humans are just beginning to comprehend these symbioses.

The plants, in an remarkably mutual and much more than symbiotic relationship with the coral polyps, live within the coral animal; the two organisms act as one and essentially consume one another's excess food production and waste. All relationships on the reef possess this sort of special mutualism, so complex and intertwined that humans are just beginning to comprehend these symbioses.

Although these relationships may be difficult to understand or articulate, they can be easily sensed. As we descend and move about in the passageways of this fascinating group of (or perhaps one large) organism(s), the simple elegance of this mutualism is obvious. The fish, although spectacular, now seem to take a back seat to the symbiosis of the reef itself -- many species of coral, sponges and countless other organisms living, breathing, hosting, consuming, competing and flourishing in these clear waters of the Caribbean Sea.

We now begin to emerge from the set of tunnels. Upon checking my instruments, I am stunned to learn that we have descended to 100 feet, essentially the depth limit for recreational diving. My air consumption, however, is fine. We emerge: directly below is a vertical wall hundreds of fathoms deep; before us is the open ocean, visible to deep blue for perhaps 200 feet. We inch out only a few feet, and glide effortlessly along the sea wall (the current is present here), glancing alternately down seemingly forever, out also seemingly forever, or back at the passing "gallery" of this engrossing structure. It is over a mile long, perhaps half a mile wide, and is completely visible to the darkness below. It is the Santa Rosa Deep. In all my years of fortunate living, studded by many extraordinary events, and certainly blessed with more than my share of serendipity, I believe I have never been more moved.

. . . before us is the open ocean, visible to deep blue for perhaps 200 feet. We inch out only a few feet, and glide effortlessly along the sea wall (the current is present here), glancing alternately down seemingly forever, out also seemingly forever, or back at the passing "gallery" of this engrossing structure. It is over a mile long, perhaps half a mile wide, and is completely visible to the darkness below. It is the Santa Rosa Deep.

We float leisurely along, carefully monitoring our depth and air consumption. David eventually locates a passageway ascending back to the beginning sand, and we then carefully proceed to the surface. As we attain our 15 foot safety stop, we are able to view the northern tip of this stunning life form; its cusp of ancient ever-changing biomass pushing rhythmically into the open ocean.