Many new divers are timid about making their first night dive — and who can blame them? First, make sure you have enough dives under your belt before making your dip into an inky-black ocean — we recommend 50 dives. There's a lot to consider, and one of them is that even with the best dive light, your line of sight won't be as good as it is when it's daytime in clear water.
Eric Douglas, who writes Scuba Diving magazine’s Lessons For Life column, recalls a night dive off Grand Cayman. "Three buddies and I were making a night dive on the Sunset House house reef," says Douglas. "We were all dive instructors, but I was the only one who hadn’t dived the reef at night before. I was more than happy to follow along and let the others lead.
"With four confident divers, and no students, we ended up goofing off some underwater. At one point, I turned around and was about to settle down onto a sunken barge in 50 to 60 feet of water. My buddy grabbed my arm and pulled me off the barge, just before my butt made contact. There was a large spiny sea urchin right where I was about to sit."
The lesson that Douglas learned? "It's important to not get too comfortable underwater that you forget the basic rules of maintaining buoyancy and staying off the bottom, to look closely before you touch anything. It would have been a miserable trip if I had been picking sea urchin spines out of my bum for the rest of the week."
Our basic tips are:
1) Choose a shallow, calm site. If it’s your first night dive, keep it simple — this is not the time to try new gear, carry a camera or go deep. If the weather is iffy, postpone the dive. Ditto for current or rough seas.
"The most common mistake among first-time night divers is not scaling things back a bit," says PADI's technical development executive, Karl Shreeves. "The reef’s a different place at night, so don’t try to go as far or do anything too complicated on your first night dive. You’ll have a lot of fun, but really simplify your dive planning and navigation. That reduces your stress usually, and makes the dive more enjoyable."
2) Start at twilight. At this time of day, you can see easily to gear up and get acclimated to the low-light conditions of the ocean. Keep in mind that a full moon will increase the ambient light once you’re underwater.
"I always tell first-time night divers that it is no different than diving during the day," says Jo Mikutowicz, managing partner of Divetech on Grand Cayman. "All of the same rules apply, but you will be able to see different marine life and probably some very awesome marine interactions."
3) Plan the dive. How long do you plan to dive? How deep? Who will lead the dive? It’s essential that you review basic hand signals. You’ll use your dive light to illuminate your hands should you need to communicate with your buddy. Immediately giving or recognizing a hand signal will be crucial if you or your buddy has an underwater emergency. Make sure to discuss your buddy-separation plan.
Forgetting about your dive plan can lead to trouble. Mikutowicz recalls one experience when she lost track of where she was: "I was intently following an octopus swimming around and I got turned around — I could not remember which direction our exit point was. I had to make a nice, slow ascent to the surface and look for our exit point, and then descend back down to get back to shore safely."
4) Pay attention to the briefing. You'll get useful tips — everything from where your entry and exit should be to the marine life you may spot.
Shreeves recalls a night dive with feeding mantas. "We were warned to stay low because while the mantas feed on plankton and they’re not aggressive at all, they’re big and hurt if they accidentally hit you — and not just a little if it’s a really big one. Well, I didn’t [stay low] and it was [a really big one that accidentally hit me]."
5) Go slow. Give your eyes a moment to adjust to the darkness of the water at the surface before descending. Use a mooring line if you’re diving from a boat and one is available. Once you've reached the point where you're beginning your dive, pause for another moment to look around.
Mikutowicz says one of the things she stresses in her briefings is "to just take it slowly — there's no need to swim as far as you would during the day."
6) Make sure you have a good primary and backup light. Test both at the surface — avoid having to return to the boat or shore because your batteries are dead and you forgot to check. Underwater, take a moment to shine your primary light on your surroundings: you may find you don’t need to turn it on at full power. And please: Do not shine your light in your buddy’s face — it will blind them and they’ll need to readjust their night vision. And it will make them very irritated with you.
"A spare light doesn’t have to be huge or fancy — just have one," says Shreeves.
"Diving with a light forces you to focus on the small things, rather than the bigger picture," says Eric Douglas. "The changes on any dive site, but especially in the ocean, caused by day turning to night, are worth seeing. Everything looks different and you will see creatures and behaviors that don’t happen during the day."
7) Secure your light and other gear with lanyards and D-rings. Underwater in the dark is not a time to drop your dive light or camera. Also, when your gear is tucked away where you can find it, it will make everything easier, such as locating your dive computer to check your depth and time.
8) Stay close to your buddy. There’s a reason that this is stressed in your open-water course.
Advises Shreeves: "Stay close to the exit with your buddy, and ideally, dive with a night diving instructor who shows you the ropes in the PADI Night Diver course. If you have some anxiety the first time — which isn’t unusual, by the way — stay where you can beat a hasty retreat. That will reduce any stress as you acclimate. Taking the course puts you with an experienced leader and teaches you the basics. Chances are, you’ll quickly discover that it’s not as scary as you might have imagined."
9) Check your gauges often. At night, it’s difficult to get a visual reference, so it’s easy to drift up or down, especially if you get preoccupied with the marine life.
Once you're comfortable in the water at night, the rewards can be huge.
Mikutowicz gets excited when she talks about her favorite night dive — the Kittiwake on Grand Cayman. "It's a completely different dive during the night. Normally when you swim through it during the day, you can see all of the entry/exit points because of all of the light coming in, but at night there is no light coming in, so when you swim inside the wreck it adds a whole new level of navigation. Knowing that wreck really well — having dove it hundreds of times during the day — makes it easy to navigate your way through, even at night. Also, there are TONS of marine life out feeding and hunting on the wreck at night. The whole wreck comes alive as everything emerges from their dark corners to play at night!"
Douglas recalls the beauty of a night dive he made at Summersville Lake in West Virginia. "Early in my dive training, we would drive here about every weekend to go diving. My instructor would teach classes, but if we weren’t in a class, we would all dive together as a community. One evening, the instructor had a couple students doing a night dive for their advanced certifications. That left a couple spots open on the small boat he used. I jumped in.
"I had made a few night dives at that point, but was anything but an old pro at it. I was happy to be part of a group dive to follow along with others and gain some experience. The visibility was great, about 20 feet or so. I noticed how different everything looked at night, but that was cool. It made the familiar look new and different.
"As we ascended to the surface, there was a full moon high in the sky above the site. We could see it reflecting on the surface of the water, so we all ended up lying on our backs on a large, flat rock (as well as you can with a tank on), turning off our lights in the shallows and watching the moon for a few minutes. It was magic."