Night Diving


Alligator Reef 1961-63

"You guys are crazy, sharks feed at night!"  When myself and two other graduates students in marine science began night diving on the outer reefs in the Florida Keys in 1961 we often encountered this kind of sentiment. Diving itself was still considered to be what we would now call an extreme sport. Diving on the outer reefs was pushing the limits and sharks were believed to be much more aggressive and dangerous to divers than they have proven to be in actuality.

I had started scuba diving in 1954 at age 15 and had already dived widely in the Keys, Cuba, the Bahamas, Mexico and Belize, Hawaii, Fiji, New Zealand, the Pacific coasts of Panama and Columbia, and the Mediterranean in Spain and Italy. No one had any idea of what happened on a reef at night or had indeed really even wondered about it. Bob Schroeder was another graduate student who was an active diver and in discussing reef biology somehow he and I began to wonder about what went on at night. Did it just get dark and most activity cease or was there unknown unexpected things going on, a night shift of nocturnal activity that took place? We decided to find out and were soon joined by Bill Davis a new student who had only just began to dive.

To start with only two things concerned us, light and sharks. The light problem was solved at first by a sealed beam auto headlight powered by a cable to a car battery towed in a float on the surface. I knew from fishing experience that sharks did come onto the reef at night and were most readily caught after dark. Whether a diver with a light would attract them was unknown so at first we carried a 12 gauge powerhead just in case.

Our first night dives were awesome. Immediately, everywhere we looked, we saw amazing things no one had any idea about. Many corals had completely changed their appearance and were covered in a frosting of expanded polyps. Instantly the whole prevailing idea of corals as passive farmers of algae sustained solely by the algae in their tissues was out the window. No matter how important their symbiotic algae they were clearly also active predators capturing and devouring planktonic prey. The dense schools of fishes so prominent in the day were gone and a new group was out and about as were a host of lesser creatures not seen in daylight. The whole familiar scene had been transformed. The entire cast of players, the roles they played, even their costume of colors had changed. It was a whole new act in the play of life.

At first it was all so different as to be a bit overwhelming. The difference wasn't just in appearance either. As biologists we realized what we were seeing had profound implications for our understanding of the structure and functioning of reef communities. Not only was this heady, exciting stuff intellectually it was a powerful personal experience as well. The whole sensation of night diving was so different. Our lights revealed a clarity and brilliance of color never seen in the diffuse natural light of day. With awareness limited to the beam of our light it imposed a focus of attention that in memory still remains sharp and clear some 40 years later.

Today of course night diving is routine, hundreds of thousands, perhaps millions of people have experienced it but despite its enduring appeal there is a vast difference in being shown what is now a well known experience and in discovering a totally unknown realm where everywhere one looks one finds unexpected beauty and mystery and magic.

For some time every dive revealed new wonders. We discovered that after dark many fishes changed their distinctive daytime colors for irregular camouflage of blotches, bars, and mottling. Still others simply faded away to pale grayish ghosts. We found various daytime species resting, tucked away amidst the coral. Numerous wrasses burrowed into the sand at dusk. Many smaller parrotfish encased themselves in a gelatinous cocoon of mucus to rest the night away. Above the reef a night shift of big-eyed nocturnal plankton feeders came forth.

The dense schools of snappers and grunts so conspicuous on the reef in the day dispersed at night to forage individually over large areas of adjacent open bottom. After dark we found the seemingly barren areas of sand behind the reef and of silt in deep water outside it were inhabited by a rich assemblage of burrowing crustaceans, mollusks, anemones, worms, urchins and other creatures who emerged after sunset. Far from being the sparse deserts they appeared they proved to be very productive communities with important links to the reef itself. They are both nourished by organic matter from the reef but in turn nourish the reef as important forage areas for the reef fishes that feed in them at night but rest away their days on the reef in schools adjacent to coral into which they can dive for shelter if attacked by predators.

After a few dives we found both our light and the 12 gauge powerhead were cumbersome and set out to improve both. At this point we still did not have enough experience to know we didn't need the powerhead. We had access to a good machine shop at the University of Miami Marine Laboratory. For lights we developed head mounted canisters using 30 watt sealed beam automotive spotlights powered by government surplus wet cell ni-cad batteries. They were clumsy on the surface but underwater they were more effective than most used by night divers today.

On the armament side we came up with the idea of using a watertight air filled barrel chambered for a .357 Magnum pistol cartridge. The air filled barrel permitted the bullet to develop full velocity and eliminated misfires due to leakage. It could be quickly reloaded by carrying an extra preloaded barrel or two, was much less cumbersome than the 12 ga. device, and it could be carried by slipping an arm through a rubber sling like a pole spear and left to hang above supported by a small float where it was out of the way but immediately accessible if needed.

It was dubbed the "Bangstick" by a fellow graduate student and a few years later it was manufactured and sold commercially along with other underwater equipment I subsequently developed. Some thousands were sold but none to my knowledge were ever used in defense. They were used however to kill everything from angelfish to a 14 foot tiger shark and a 500 pound grouper. One customer who couldn't wait for some innocent marine creature tried his out on a rubber duck filled with water in his home pool and was impressed to find it cracked the pool. A Miami dive shop proprietor tested one on a palm tree outside his shop. It went completely through the tree and into his car. In due course two people ignoring clear instructions and common sense by loading without the safety pin in place and using their thumb over the end of the barrel to shove it into the receiver managed to blow off their thumb. One was a surgeon. Every month of every year a similar number of people are killed by firearms in the U.S. as were killed in the September 11 terrorist attacks. Like the Bangstick one begins to wonder just how necessary such things really are.

When we began night diving my underwater camera system was a Leica M2 with a 50 mm lens and bulb flash. Canon had only recently introduced its first SLR and I had one but no housing existed. We needed a better means of recording the amazing things we were finding and soon set out to construct a cylindrical acrylic housing for the Cannonflex. I had 35, 50 and 100 mm lenses as well as a couple of diopter lenses for closer work. Extreme wide angle and macro lenses were still a couple of years away. For awhile I used the little AG flashbulbs but soon built a housing for an electronic flash. This rig would have been among the first use of SLR underwater. From the very first use the results were like nothing anyone had seen before. Not only were the pictures noticeable better than what could be done with a rangefinder but they were taken at night and all of subjects were ones no one had previously photographed.

When I had accumulated about 40 or 50 good images I contacted National Geographic Magazine and inquired if they would like a story. They responded enthusiastically and began to supply us with film and equipment. In January 1964 our story on photographing the night creatures of Alligator Reef appeared in the magazine sparking a wave of interest. The rest, as they say, is history.