Sunday, October 19, 2014

SCUBA DIVING IN THE DARK - NO LIGHTS, NO MOON




I thought my friend and fellow dive instructor, Jim Brown, was joking when he invited Skeeter and I to do a no-light, no-moon night dive with him. Though I had turned my flashlight off during numerous night dives for a few minutes each dive, I had never considered doing a night dive with no light at all. And not even the glow of the moon? It sounded absolutely insane!


I pictured myself crashing face first into fire coral and sea urchins, ending up lost and by myself, and being left as shark bait. But Jim assured me that he had done this lots of times in Mexico, and quite a few times here in the Virgin Islands…and he lived to tell the tale. He promised me that the experience would blow my mind.  And it DID!

We geared up after the sun had completely disappeared.  We each had a light with us “just in case,” hanging from our BCD’s.  Jim said he usually does the first 5 minutes of the dive with the light on to get oriented, but I talked him into not turning on our lights on at all.  I figured we might as well let our eyes adjust as quickly as possible.


We dived from the shore of Secret Harbor in St. Thomas.   I was nervous but excited.  We waded into chest deep water, and then slowly descended toward the sandy bottom.  We waited a minute to let our eyes adjust, and then Jim led us toward the reef.  I was shocked how much I could see. 


Once my eyes adjusted, I could see about 10-15 feet.  I could not make out details or colors, but I could make out the general shape of the reef, sea urchins, and Jim and Skeeter.  We followed the contour of the reef around the edge of the bay, with reef to our right and a sandy grassy plain to our left.  It was incredibly peaceful in the dark but starry sea.  The only sound was the sound of our slow steady breathing.


It was incredible…like being in outer space!  Tiny little lights began firing all around us like twinkling stars.  I could see the silhouettes of Jim and Skeeter, especially the glowing pixie dust coming off their fins.  It reminded me of a scene out of Peter Pan.  Every time I waved my hands, hundreds of tiny little particles would magically light up a bluish-green color.  Even my bubbles were lighting up!  Strands of lights a few inches long were sequentially firing around us.  They were mesmerizing!

Part way into the dive we slowly came up to the surface to verify our location.  We could still see the slight glow of the lights from the nearby houses on the cliff above, and we wanted to head toward the darkest possible spot to maximize our experience.

Being on the surface when I can’t see what’s below me makes me feel very vulnerable, so this triggered a series of unnerving thoughts.  We descended back down, and this time my breathing was not quite so slow or relaxed as before.  I tried to stop my imagination from running wild, but heading out of the bay and around the corner into open water and across a sandy grassy plain with no reef for protection added to my increasingly stressful thought patterns.

FACT: Sharks are more active at night.  FACT: There had not been an unprovoked shark related death in the St. Thomas since 1963.  I argued back in forth in my head trying to decide whether or not it was logical to be afraid.


I swam over and took Skeeter’s hand to help me calm myself down.  It helped.  Watching Skeeter hanging upside down, flapping his arms like a bird, swimming like a dolphin, and playing Street Fighter II and shouting, “Haduuuken!” through his regulator as he threw balls of bioluminescence into the darkness also helped me to laugh and refocus on positive thoughts.  Now my mind focused on the wondrous bioluminescent lights blinking all around me instead of my imminent death.

Our dive was a shallow one, never dropping below 20 feet.  Since we were all experienced divers, we didn’t use up much air.  We were able to roughly monitor our air gauges because they had a slight glow to them.  Though we couldn’t read the exact number on our gauges, we could clearly see that we were well in the safe zone.  We enjoyed our dive so much we stayed under for almost an hour and a half!

I am so grateful that my crazy friend Jim talked us into this.  It was seriously life changing.  I searched the internet to try to find evidence of anyone else doing such a crazy kind of night dive but found none.  I found talk about no light night dives during a full moon, but absolutely nothing about no light night dives with no moon.  This is an experience that is absolutely incredible, but I would only recommend it to extremely experienced divers.  And of course only in the most ideal of conditions.

I spent the entire next day researching bioluminescence, and can’t wait for my next opportunity to try this again.

The ocean is full of bioluminescent creatures.  Most of the ones we were seeing were DINOFLAGELLATES, single cell bioluminescent algae.  They collect energy during the daytime, so the higher the intensity of light the previous day the more light they will emit.  Even the slightest movement deforms the cell and triggers a chemical reaction which causes a flash of light.

I was really curious as to what the benefit of flashing could possibly be for these dinoflagellates, and I found out that they do this as a burglar alarm.  When a creature comes close to eat them it triggers the flash of light, which attracts a secondary predator.  The secondary predator comes and eats the creature that was trying to eat the dinoflagellates!

We were also seeing some bioluminescence from COPEPODS, a small transparent crustacean that releases chemicals into the water to produce a glowing cloud of light to distract predators while they escape.

There are also tons of other bioluminescent creatures in the ocean.  Some jellyfish, comb jellies, bacteria, sea pens, fish (including the cookie cutter shark),  squid, anglerfish, and sea stars are bioluminescent.  Each of these creatures uses their bioluminescence for defense, offense, and/or to attract a mate.

I learned so much from these two websites:


And one of my new  heroes is a marine biologist by the name of Edith Widder.  You can watch a couple of her awesome videos by clicking below:

 
“The weird and wonderful world of bioluminescence”

“How we found the Giant Squid”