If you are already a certified diver and are looking for a new twist to your underwater career, then try diving at night if you haven’t already. There are many advantages to night diving and it’s a good way to get that ‘first dive’ feeling that you get on your Open Water Course. Some people ask “why bother diving at night” “can you see anything in the dark?” Night diving can be an exhilarating experience, many people describe it as like going on their first dive all over again.
Night Diving Techniques
There are a few different techniques to diving at night, but most of it stays the same. You will carry a dive light on you, which is basically a torch that has been sealed water tight and they usually work to a maximum depth of 30m. Ideally you will carry a second torch as a spare in case the first one stops working. If you have to switch onto your backup torch then this means you should end the dive, so some people like to have a backup to their backup!
What can I see Night Diving?
Many of the marine life we see is nocturnal. Things like stingrays and shrimp are visible in daytime by looking under rocks and coral shelves, but at night they come out to hunt. You can often see many types of Rays swimming over sand patches digging for shellfish such as crabs. Also in many parts of the world night time is where the hunting begins for one of the meanest looking fish around; the Great Barracuda.
Diving with a torch brings a different perspective to dive sites you know and love. As you descend the water absorbs the light from the sun, however diving with a torch allows you to bring the light down with you. This means that you can see corals and fish with their real colors instead of that washed out look.
What if I get lost?
Although many aspects of diving at night remain the same as diving in the day time, there are some differences. For instance it is much easier to lose your dive buddy. This is why many divers choose to attach a marker light to their SCUBA tank so if they stray too far away the faint glow will be easier to spot. If you do ever lose your buddy you should do the same as in the day, look around for one minute before slowly ascend. It helps if you cover the light source so that it will be easier to see any traces of light being emitted from them. Banging on your tank can help get their attention if they haven’t noticed if you are missing.
Another thing to take into consideration is that now you are carrying a powerful source of light on you. Shining this is the eyes of other divers will make them see stars temporarily so avoid this by not pointing it directly at their faces. If you are trying to illuminate a hand signal then you should make your signal at waist level, and point the torch towards your hand instead of towards them. The same rule applies to fish, possibly even more so.
Respect the Marine Life
The marine life you will see on a night dive will be nocturnal. The nocturnal creatures have very sensitive eyes to the light and if you shine your 1200 lumen light directly into them, then you will either temporarily or permanently damage their eye sight, making it hard for them to feed and leaving them open to predation. If you want to illuminate a fish then you should point the torch closer to their tail, or mid body on a larger fish. This will make them easy to see, but not damage their eyes. But please don’t light them up for too long, as predators will use this as an opportunity for an easy catch.
When holding a torch you should always keep the lanyard around your wrist in case you drop it, and it should always be held in your right hand as you will be using your left all the time to adjust your buoyancy.
Commincating on a Night Dive
Communication with your buddy can be much harder at night than it is in day time, so we try to keep it simple and only worry about the important things. Apart from illuminating our hand signals there are 3 basic ‘light signals’ that we can perform for most things. The first is slowly circling the light around an object or on the sand. Around the object can either mean look at this, or more often used as “OK” (Both question and answer). Waving your torch from side to side slowly means problem, such as difficulty equalizing or similar issues. Waving your torch rapidly from side to side means there is an emergency such as out of air. For this reason it is important not to move your torch about too much underwater as it can make other divers think there is a problem. If you are going to move it do it slowly and controlled instead of erratic panicked looking movements.
Make sure you frequently check your buddy’s air. When you do this remember that most SPG face’s glows in the dark, so instead of trying to work out what you have past the glare, just hold your light against the face for a few seconds and then look, your air pressure will be glowing.
When you are night diving it is not only dark underwater but also on the surface, therefore boats or other watercraft cannot see you. I always recommend that you keep the torch pointed on you while swimming on the surface to make sure you are easily visible. It might be nice to look down at the fish and the reef, but you don’t want a boat driving straight over you because they didn’t know you were there!
The same rule applies when ascending, sending up an SMB is useless unless you have a light attached to it. I prefer to point my torch upwards while ascending so that from the surface you can see a glow getting bigger and bigger, also your exhaled bubbles help multiply this effect.
Night diving is a great experience and defiantly worth trying, it can be done as a part of the Advanced Open Water Course as an Adventure Dive, or to fully understand night diving procedures you can take the Night Diver Specialty Course.
‘Night Diving’ was written by Mike
Related Blog: 9 Tips for Night Diving