In the video, it looks really creepy, like another planet. Particles of life float in pitch-black chilly depths like tiny extra-terrestrials. In this uncharted territory, proper skill and training are necessary to witness this eerie and foreign silence.
For the cave divers in the video, USF professor James Garey and graduate student Damien Menning, it’s just another Thursday afternoon in North Florida, not outer space.
Underwater cave diving caters to a relatively small group–those who have specialized equipment, proper training and aren’t bothered with the dangers that lie beneath the limestone.
If something goes wrong with this type of diving, it can result in dire consequences. If the equipment fails or a sudden burst of panic occurs half a mile back into the labyrinth of twists and turns, the diver can’t just resurface. They must navigate their way back out to safety. This risky dive can lead to the worst-case scenario of decompression sickness, which can be fatal, or drowning.
Risks aside, these passionate divers thrive on the thrill of the unknown and the unexplored. Garey moved to Florida in the late 90s and started diving in local springs, sparking his interest in the biology of underwater caves. He has dived in anywhere between 50 and 60 different springs and sinkholes in Florida.
It has become one of the main projects in his life.
Garey has been monitoring Double Keyhole, an underwater cave just north of Hudson off the Gulf of Mexico, for almost six years. He travels to the cave every Thursday along with Menning and usually a third person who stays on the boat to be there in case of an emergency.
This is one of many salt marsh springs scattered along the coast of the Gulf of Mexico. This one in particular is close enough to be dived and studied weekly by Garey and Menning.
So if it is dangerous, why is it important to study these caves, and what exactly goes into the science of cave diving?
Underwater cave biology
Garey and Menning primarily focus their studies on the biological chemistry of the underwater caves, collecting samples to study after each visit.
“I’m most interested in the biology of the spring and how it affects water quality. There’s just so little known about them,” Garey said. “It turns out that this one little spring that we study can put out as much water as the Hillsborough River on a good day.”
The biology isn’t really well understood, many of the scientists today are not looking specifically at the bacteria. Instead, they are bringing nets out to catch the larger animals. Very few people are looking at more than one organism at a time.
“After one hour of diving, we then bring samples back to the lab,” Menning said. “It takes approximately 30 hours to process each sample. That’s going through water chemistry, DNA, reactions and then data analysis.”
“It’s amazing how Florida is just like a big chunk of Swiss cheese,” Garey said.
The limestone rock underneath much of Florida is full of holes that hold and clean our drinking water supply. It doesn’t only create caves for diving. One of these underground caves can cause traffic jams, too, as it did when a sinkhole formed on Fletcher Ave.
“There’s a sinkhole that opened up near Fletcher recently,” Garey said “It was just a natural cavity in the rock since we live on limestone.”
This sinkhole didn’t cause extensive damage, though more serious cases could open up under buildings and homes.
“It’s a very common occurrence in Florida,” Garey said. ”There’s an issue right now with home insurance companies when a sinkhole opens up under somebody’s house and it causes damage. Most sinkholes don’t become giant open holes, but some can swallow part of the house and cause significant damage.”
There is no way to predict when a sinkhole will occur, since there are underwater caves spread throughout Florida that have yet to be discovered or fully studied.
The BP oil spill
When the major oil spill occurred last year, Garey and his partner closely monitored the water at Double Keyhole. They were not sure how far the oil was going to drift and whether it would adversely affect the water quality there.
“It’s a brackish spring and the interesting thing is when the tide goes up, the spring flows backwards, so Gulf water goes into the cave. We were hoping the Gulf oil spill would not bring oil filled waters back into this cave,” Garey said.
“If the water had been contaminated with oil, it would have gone straight into the fresh water supply and would have contaminated our drinking water.”
Garey has been cave diving for enough years to be confident in what he is accomplishing, along with Menning. Both have enough trust in each other to successfully complete these dives on a weekly basis.
There is much still to be discovered and the risks are there. But with experience, Gary doesn’t fear the dangers in his work as the benefits of his studies outweigh the risks.