Easy Diving | Night Diving
DIVE’s blogger Crowley (real name Mark Russell) takes a no-nonsense approach to the techniques and skills needed to enjoy your night dive
I’ll be honest here: anybody who knows me knows I’m not one for night diving. But let me clear this up. It’s not that I don’t enjoy night diving, it’s that I work full time as a dive instructor. After working a 12 hour day, pretty much the last thing I want to do is go diving when I could be at home eating dinner (or in the pub, drinking dinner).
And I was also told this story about a night dive by a friend. Going on his merry way, underwater in the dark, he turned around to see seven pairs of beady green eyes just a few feet behind, following him. They weren’t an especially dangerous species of shark, but they were sharks following him, nonetheless. And it was dark. So very, very dark….
If that hasn’t given you the willies, night diving is actually one of the most wonderful kinds of diving. The ocean comes alive with a whole new set of creatures that you either don’t see during the day, or who behave completely differently at night. While parrotfish sleep, after creating themselves a protective bubble of mucus to doze in, lionfish use the cover of darkness to go hunting.
As this is an Easy Diving column, I’m not going to be talking about extreme wreck diving in deep water and strong current late at night (I’m not sure this is within the safety manual of any agency, really). Instead, here’s a few pointers for basic, recreational night dives. They may come in useful if you wish night dive without a professional guide, because your professional guide has gone home to bed with the pet cat and a good book by 9pm. Because that’s the wild and crazy life we lead!
Firstly – the main requirement for night diving is, of course, night. ‘No shit, Sherlock,’ you may say. But consider that starting a night dive in complete darkness may not be ideal, especially if you’re shore diving. Gearing up and entering the water may be best with a little bit of light left in the sky; it makes equipment checks, negotiating a tricky entry into the water, and getting everything organized before you make your descent a bit easier. Yes, I know you still have to exit in dark conditions, but hopefully it’s fresh in your head then – as in you know where that big slippery rock is so you’re less likely to wipe out. Even if the sky is not completely dark when you descend, once the sun has set, the water most assuredly will be.
In the same way that it’s much easier to walk around in your own home with all the lights out – as opposed to a random hotel room where trying to reach the lavatory ends up with you trying to flush
the TV set – don’t dive an unknown dive site at night. Even familiar surroundings appear different and confusing in the darkness. Needless to say – and I’m repeating the basic training manual here – big waves, strong currents and other poor conditions that might be manageable during the day become problematic at night.
Prior to entering the water, take a good long look at available light sources. If you’re boat diving, the boat should have big lights so you can find your way back. If there are multiple boats in the area, try to note their positions. Yes, they might move, but keep the light sources in visual range if possible – ending up on a different boat is better than not ending up on any boat at all.
If you’re diving from the shore, have a look at what’s available. While I was working in Egypt, most of the night dives I guided were in Na’ama Bay and one of the beach front hotels had a bright blue star on top of it. This was my visual cue. On the other hand, in my current location (Nusa Lembongan, Bali) there are very few bright lights, and more careful attention to navigational is important.
Don’t stray too far off the beaten path. Keep as many visual references around you as possible and if you do have to cross featureless terrain, note depth changes, sand ripples, bottom composition and kick cycles. Make notes on a slate if you’re not sure you’ll remember.
It goes without saying that you need to have at least one light, and preferably a backup. These days, LEDs are the norm for dive torches: bright, and they don’t burn out as regularly as filament bulbs. In any case, switch your light on before you enter the water and keep it on. Any electrical device draws more current during start up and this is therefore where they’re most likely to fail. Those of us who still remember the warm, soft, soothing glow of a filament bulb will remember that they tended to explode when you flicked the switch, as opposed to halfway through the dinner party, and the same goes for torches.
A backup is useful, but not mandatory. Whether diving with two people or a group of ten, it’s unlikely that everyone’s torch is going to fail, but it’s still possible. At least one person in the team, although preferably all, should have a backup light.
Some people carry flashing strobes attached to the back of their tanks, but these annoy the smeg out of me with all the flashing and blinking. Yes, they serve a purpose but for easy night diving, there are better alternatives. Firstly, the glow of a torch carries a long way in good visibility, and keeping track of other divers is fairly simple. Is one of the group out of sight? Have a look for their light and swim over there. Secondly, stay together! Don’t randomly swim off and if your light fails underwater, locate the rest of the group via their own. Use some common sense and don’t stray too far from the others.
Use good judgement in terms of group size too. Don’t try to dive with a huge group if you’re not all going to be able to see each other.
If you’re diving at a site where multiple teams will be in the water, some form of group ID is useful. Firstly, make sure you know what each member of the group is wearing – paying particular attention to their fins. If you need to identify a diver underwater, don’t shine your light in their face. Waggle it over their fins and then up their body – hopefully this information is enough to identify the diver as one of your group. However, it’s possible a diver from another team happens to have the same gear. One relatively inexpensive solution I used while working in Thailand was the glow-sticks that are popular with clubbers. These chemical lights, which you snap then stick the ends together to wear as a bracelet, were perfect. Everybody in one team could wear a red light around their tank valve, other teams could have green or blue. It was a really useful, really cheap solution to the group ID problem.
On night dives, divers tend to group together more tightly. Coupled with the lower visibility, and extra stress and nervousness involved, this means there’s a lot of knocking into people and kicking in the head in the dark. Which, of course, only adds to stress levels. Nerves are perfectly normal, and even dive professionals are likely to have a few extra during a night dive. As a consequence, it’s common to burn through your air supply a bit quicker than normal, so it’s a good idea to limit your depth (12 – 16m is about the maximum I’ve used over the years) and check your air supply more regularly. Most analogue gauges are luminous, so give them a good shot of direct light from your torch before the dive and top it up every time you check the gauge. Most dive computers have a backlight – make sure you know how to activate it before you start your dive.
Above all, enjoy it. You’ll enter a whole different world. If you’re in the tropics, dim your lights and wave your arms around and watch phosphorescent plankton light up the darkness. Look for all the crabs, shrimp and octopus that you never see in the day and watch out for the fish that will hunt in the light of your torch… and on that note, if you’re ever night diving in Na’ama Bay, watch out for the lionfish, because they turn into little bar stewards after dark!
- Plan your dive and stick to it carefully
- Make sure your torch batteries are charged, or you have spares
- Carry an SMB. Remember that shining your torch inside an inflated SMB at the surface gives you a bright orange lightsabre – a useful visual aid if you are lost or separated
- Dive in unfamiliar surroundings unless you have a good guide
- Stray too far from your buddy or dive group
- Panic! It’s normal to be a bit more nervy. Relax, dive carefully, pay attention to what you’re doing and where you’re going, and enjoy it.