Research by marine biologists from Wageningen University has shown that feeding on zooplankton by scleractinian corals has been greatly underestimated.
|A Glimpse Below and Beneath: The Bahamian Blue Holes|
|Written by Michael Lombardi|
The underwater cave… perhaps the most unforgiving environment on the face of the Earth. A mile or more underground, no light, and over an hour away from seeing clear blue sky, not to mention your next breath of fresh air. It’s a place where no one will hold your hand, there’s no one to call for help, and chances are there are few who would dare attempt a rescue, as if you have a chance anyway. It is blacker than the darkest overcast night during a new moon, there is ZERO room for error; and a mistake, lapse in judgment, or shudder of uncertainty can prove fatal… as it has for many.
Yet, the rewards of exploring underwater cave systems are more fulfilling than anything else imaginable. Picture a tunnel, having never before been viewed by humans. You are the first, and potentially the last set of eyes to set sights on this mysterious habitat. There’s one way in, and one way out, and your turn to head home is met with the disorientation of a corn maze… tunnels after tunnels, upon tunnels… upon tunnels; with the way out marked only by the thin guideline that you were responsible for laying down. Heart skips a beat, maybe two… maybe three. But you’re ok, and there on a mission.
Figure 1, above right: The entrance of Mystery Cave Blue Hole, Exumas, Bahamas. Mystery Cave is one system that has been thoroughly explored and scientifically investigated. Mystery has produced more than a dozen new species of marine life. Local developments are having devastating effects on the marine community in the system (photograph © M. Lombardi).
The island nation of the Bahamas lies to the south and east of Florida (USA) and rests atop a carbonate platform that has been subject to glaciations, rises and falls in sea level, and various erosional processes, all of which have sculpted miles of underground cave systems. Most of these systems remain unexplored, as logistics for expeditious field events in this part of the world are still quite challenging. Take these efforts underwater, and the level of complexity increases yet again.
Figure 2: Dr. Marc Slattery collecting specimens within Mystery Cave (photograph © M. Lombardi). Watch a dive through one of Bahama's caves.
“Most of these systems remain unexplored, as logistics for expeditious field events in this part of the world are still quite challenging”. – Michael Lombardi.
Scientific examination of underwater cave systems has not been as commonplace as other underwater environments due to the considerable training, financial, and other required ongoing commitments. Additionally, when exploration caliber diving is coupled with scientific task loads, the margin for error can increase. It should be noted, however, that exploration teams have documented many successes in advancing science.
Why take on the risk?
The wealth of knowledge gained by enabling science in these habitats is unsurpassed, and in some cases includes major paradigm changing discoveries. For instance, in the Bahamas specifically, deeper and further exploratory dives just since the turn of the century have uncovered geological formations that were thought not to have existed in that part of the world. This changed our understanding of when these caves were formed - by over 200,000 years. By using current techniques in geological dating and observing mineral deposits in these speleothems, clues about global climate change are unearthed and are contributing to the global picture.
Figure 3: The entrance to Norman’s Pond Caye Cave. Many blue holes have shore or inland access only, causing some difficulty in trekking with the considerable amount of gear needed for safe exploration (photograph © M. Lombardi).
The Bahamas is also home to both inland and ocean caves. Inland caves are generally geographically isolated, creating unique habitats for cave adapted organisms such as small fish and shrimps, to evolve independently. This is a perfect model to study evolution in real time. Ocean caves usually siphon rather hard, with the tides bringing clean ocean water and its associated nutrients into all parts of the cave. Ocean caves are home to a number of invertebrate species, namely sponges, which can feed due to the strong currents bringing food into the system. In some cases, sponges living deep and in the dark have evolved into new species. Often, uniquely adapted sponges have unique physiologies and associated chemistries. Such unique properties have potential applications in the quest for biotechnological discoveries. The ability to improve human quality of life is cause enough to continue scientific exploration of these cave systems. It is a habitat with much promise, yet a source for so much debate.
“It is a habitat with much promise, yet a source for so much debate”. – Michael Lombardi
Older generation Bahamians, still subscribing to Lucayan Indian folklore, view the blue holes as taboo, as a number of children and pets have vanished into these poorly understood water filled pools. The ‘Lusca’, a creature from this folkore, is said to lurk the holes, and is the reason for such mysterious disappearances. This cultural (mis)understanding makes access to several blue holes difficult, since landowners are hesitant to allow ‘crazy’ explorers to venture there. This disregard and misunderstanding is also leading to the destruction of these poorly understood habitats, since present day local developments are commencing with no attention paid to sedimentation rates resulting from dredging and construction debris on these submarine systems. This sedimentation is potentially destroying resources that are yet to be discovered, such as possible cures for disease.
Today, there lies tremendous opportunity to merge interests and resources to facilitate sustainable investigative programs surrounding the blue holes. Each system is unique, as it is subject to varying flow rates, exposure and connectivity to the ocean environment, depth, and geology. The blue holes represent a complex area to focus exploration and scientific efforts, yet are a critical one, offering opportunities for true exploration, pure scientific discovery, resource management, and conservation.
“The blue holes represent a complex area to focus exploration and scientific efforts, yet are a critical one, offering opportunities for true exploration, pure scientific discovery, resource management, and conservation”. – Michael Lombardi
Figure 4: One of the many alien-like creatures discovered by the author, probably a sponge. Such new species are a target for biomedical investigation (photograph © M. Lombardi).
Bahama Blue Hole Resources
Dr. Tom Iliffe’s Cave Biology website www.cavebiology.org
Bahama Caves Research Foundation www.bahamacaves.com
About the author
Michael is the Founder of ‘Ocean Opportunity’ (a 501(c)3 not for profit organization), an environmentalist, author, and explorer. He is a Member of the Explorers Club. As a contract undersea specialist by day, his work has taken him from New England to as far as Antarctica. He serves on the Membership Committee of the American Academy of Underwater Sciences and is an elected Board Member to the Society for Human Performance in Extreme Environments. His work has been featured on NBC’s Today Show, and he has been recently recognized among Providence RI’s 2007 ’40 Under Forty’ for his work in undersea exploration.
Michael Lombardi, PO Box 603319, Providence, RI 02906
Figure 5: Explorer Caleb Thibeault exiting Norman’s Pond Blue Hole (photograph © M. Lombardi).