The sea changes after dark, and so do the rules

A spotted eel has a look around during a recent evening off the Upper Keys.
A spotted eel has a look around during a recent evening off the Upper Keys.

The sun slipped into the ocean; the kaleidoscope of tropical sunset colors surrendered to the dark of night.

I stood up; safety checked my dive gear, and walked a few steps from the dock of the Carib Inn, located on the Island Bonaire, to the edge of the water. It was calm and pleasantly warm.

I waded in until the water reached my waist, slipped on my dive fins, checked a heading on my compass, turned on my dive light, submerged into the dark and began my journey — a night scuba dive.

Wow! The reef certainly didn’t look or sound like this when I explored it earlier in the day. What was making those eerie sounds? What were those murky shapes lurking in the distance just out of reach of the beam of my underwater light?

The night crew of ocean critters had come out. The day crew were home hiding in the protection of their holes or crevices.

The water was alive with feeding invertebrates, amazing bioluminescent creatures (organisms that glow in the dark), parrot fish sleeping in cocoons of their own mucus, octopi, moray eels and nurse sharks. Some of the coral was “blooming” to absorb nutrients from the nearby water.

I reached the bottom of the slope at about 100 feet deep and saw a fearsome looking creature opening and closing its teeth filled jaws. 

“Gotta get a photo of this,” I told myself while pushing several times on the camera’s shutter release trying to get a suitable image of the spotted moray eel.

After checking my air gage, and taking a reverse heading on my compass, I slowly cruised up the slope to 15 feet deep and did a 3 minute stop to let the excess nitrogen picked up during the dive “vent out.”

I finned toward the shore until my dive computer told me I was in 3 feet of water — a good place to standup, remove my fins, and walk back to the beach.

There were the shore lights, the dock and the hotel, exactly where they should be. “Time for a Margarita,” entered my mind as I saw the happy folks sitting in lounge chairs sipping cool ones.

The Florida Keys, with its varied reef formations, abundance of colorful tropical and pelagic fish and ship wrecks, is a great place to night dive. Afterwards, there are an abundance of places that sell great Margaritas and have bands that play Jimmy Buffet songs.

So, being the adventuresome type, before going to the tiki bar you won’t bewasted away again in Margaritaville searchin' for (your) lost shaker of salt,” (from Margaritaville" by Jimmy Buffet) – you’ll be night diving!

Many divers take their first night dive as part of an advanced open water course or a night diving specialty course.

The night diving course covers underwater lights, compass use and natural underwater navigation, equipment, buoyancy control, underwater communications, entering and existing water, and identifying how plants and animals differ or change behavior at night.

If you conduct a night dive offered by one of the dive operators in the Keys, you will be able to rent the gear you need, be helped setting up and safety checking your gear, be briefed on the dive and, in many cases be guided by an instructor during your underwater adventure.

Night diving is fun and can be exhilarating. Instructors agree on a few steps you should take to make sure your dive is safe and enjoyable.

For starters, it is a good idea not to use new dive gear for the first time. You need to be very familiar with your gear and how it operates before you take a dip after darkness settles on the ocean.

Unless you are being carefully watched by a dive guide, you should know and be comfortable with your dive buddy because of the increased difficulty communicating and staying close together during a night dive.

Many Keys dive operators attach a “glo-stick” to your tank valve to make it easier to spot you underwater. The dive group may have one color and the divemaster a different color. Some experienced night divers attach a strobe light to their tanks.

If you are doing a shore dive, plan on entering the water right before the sun sets — both for checking gear and identifying entry and exit points for navigation purposes. Make sure there are identifying lights on land close to the water. Many night divers bring two or more lanterns and place them on the shoreline to help navigate their way back to the beach.

As with all dives you should review safety procedures, plan your dive and dive the plan.

Because you are diving in the dark, a bit about dive lights is good to know.

For boat dives, you should check your and primary and backup dive lights to ensure that they're working properly before leaving the dock. It is also a good idea to have a lanyard or other way to attach your light to you or your equipment.

Watching your dive light spiral down toward the dark abyss is a very unpleasant experience.

Turn your light on before entering the water, and off after leaving the water.

Make sure that you look down into the water, using you dive light, to check for other divers or obstacles before you enter the water and during your descent.

The same holds true during your ascent to the boat. You don’t want to bang your head into a several ton vessel that may be rocking in the waves.

What about your dive gauges? Most will glow if a light is shined on them for a few seconds, allowing you to read them or show them to your dive buddy or instructor.

Dive signals at night are bit different than during day dives. To signal OK you can make the OK sign with one hand while shining your light on it or, if your dive buddy is too far away to see your hand, you can aim your light down and draw a circle with its beam.

To attract another diver's attention, wave the beam of your light back and forth on a lower part of his or her body. A more rapid wave can mean you are having a problem.

Be careful where you point your light. Looking directly into a powerful dive light can temporally blind you or your buddy. 

Many dive boats have flashing strobe lights underwater to make them easier to locate at the end of your dive.

If you surface far from the dive boat, point your light at the boat until you get the crew's attention, and then shine it down on your head so the crew clearly can see you.

Slow and relaxed is the rule for night dives. You will see more and your dive light will make the coral even more colorful and vibrant than it appears during the day.

Just take in the beauty while listening to the Darth Vader sounds of your breathing. (Historical note- Darth Vader used an old style Dacor regulator to make his breathing sounds.)

OK, now it’s time for Margaritaville. After your Keys night dive you will have a great adventure to brag about.

Many divers remember their night dive in the Keys as the high point of their trip.

For more on night dives see: http://scuba.about.com/od/nightdiving/a/whatnightdiving.htm or http://www.scubadiving.com/article/other/night-diving-made-easy

Don Rhodes, in addition to a career in government affairs, has taught scuba for 29 years. He and his wife retired to Tavernier four years ago, where he works as an instructor for Conch Republic Divers.