A formation that appears solid dissolves in a cloud of bacterial flakes, the floor shifts and bulges with each movement, and strings of bacteria curl with the slightest fin motion. Sistema Pandora is a warped universe, one in which everything is sliding and shifting around the diver. The challenge of the exploration lured us back this week, and we were again humbled by the number of tunnels snaking out in every direction. This cave will keep us busy for as long as we have the energy and permission to explore.
THE DIVE
We only had one day for diving in Pandora this weekend, as our first day was used to install flowmeters for on a small science project in the nearby Sea Cave 1 and Sea Cave 2. We planned and executed a single stage dive on 32% nitrox with 10 minutes oxygen decompression, run time 185 minutes, max depth 85 feet. Given the excessive number of leads near the existing mainline, we felt this would be sufficient to empty a reel or two, and give us a bit more insight into the system, and it was.
We used the stages to swim approximately 1500 feet into the system, dropped them, and started exploring along a northeastern lead. We placed about 1000 feet of line along the lead, surveyed back, and then swam the mainline towards the exit. We dropped the stages near another promising lead, and laid another 150 feet of line down a western tunnel before reaching turn pressure. Both ends of line appear to go, and there are many, many remaining tunnels and leads to check out near the entrance.
BACTERIA
Pandora is completely covered in bacterial growth. The cave appears to be a solution cave, subject to the typical cave formation process in the area, with speleothems clearly present. All the formations are cloaked in bacteria and most surfaces are fuzzy. I noted three distinct styles of bacteria: net-like bacterial webs making up the furry covering, thin bacterial straws, and thick mats of bacteria on the floor. Every exhalation, every fin movement, causes the bacteria to fragment and fall — without contact and from some distance. The lead diver has clear visibility, but the second diver must swim in what we’ve dubbed a “guck out” and the survey out is definitely challenging due to the highly reduced visibility.
HYDROGEN SULFIDE
There is a moderate concentration of hydrogen sulfide in the water, most likely produced by the bacteria. It is no-where near the concentration in well-known dive sites such as the Pit or Angelita, but it does reduce visibility and it does stink. Oh lord does it stink. Diving for extended times in even a light concentration of hydrogen sulfide is both physically and mentally challenging, and while neither of us experienced any lasting adverse effects, the water did sting my face when it dribbled into my mask. Most of the metal items on our gear that were not high-grade stainless steel turned black and we learned a little about the quality the metal in a few pieces of dive gear.
FLOW
Unlike Sea Caves 1 and 2, Pandora does not seem subject to strong currents. However, we did experience a very gentle downstream flow during the dive in, and a light current reversal on the way out. This was unexpected as we did not feel any flow on our first dives in Pandora. Maybe we missed it, or maybe the recent strong rains or tides had some effect.
DECONTAMINATION
Pandora may have similar bacteria to those found in other salt-water, costal caves in the area, or the bacteria may be different. The fresh water caves certainly don’t have anything like the bacteria in Pandora! While we do not expect that the bacteria would survive in fresh water, one can never be too careful, so we soaked our gear in chlorine after the dive to avoid cross-contamination and bacterial growth on the gear itself. The last time I dived there, my inflator became a petri dish of green and brown fuzzies.
SURVEY
The previous survey of Pandora (July 2015) and the current survey. The new sections are the bright yellow line (Under the Stuff Section) in the northeast quadrant and the light blue line (Golden Air Section) running west. The main entrance is at the north west (blue and red loops). We added the inital lines, Steve went crazy with the reel and a scooter for a week and added the rest, then we returned and continued the project.
Pandora is enchanting. It’s not what I would term “beautiful,” but the intricate nature of the tunnels, the unusual bacteria, and novelty of taking a boat to a cave dive make exploring this place addicting, and we can’t wait to be back for more! UPDATE: We have now posted a video of Pandora Cave.
Pandora is a costal, brackish and salt water cave first dived by Natalie Gibb, Vincent Rouquette-Cathala, and Steve Bogaerts in June 2015. The exploration is on going.
