What to Expect on Your First Night Dive
by Ryan Conery:
Diving at night may seem daunting at first. However, more often than not, I see divers fall in love with it. It truly is one of my favorite types of diving. With the proper equipment and the right planning, you too can enjoy the wonderful experience of night diving.
So, why do we bother diving at night in the first place?
The environment completely changes. The same dive site you have seen multiple times turns into a whole new world. As the sun sets, a shift in wild life occurs. An amazing new array of creatures emerge from their homes. Octopuses come out from their hiding holes to crawl along the reef. Squid dart in and out of your vision and lobsters travel in packs across the ocean floor. Many fish will settle down into the nooks and crannies along the reef to rest for the night. Sharks are out prowling for their prey while the vibrant coral polyps open up to catch nearby zooplankton floating in the drift. The nocturnal realm hosts a variety of new and interesting organisms.
As you learned in your Open Water course, color becomes absorbed by water the deeper you descend. However, during a night dive, you are continually reintroducing the spectrum of light. This causes the scenery to be illuminated in a dazzling show of color. My favorite feature of night diving is the bioluminescence. If you cover your light and wave your hand around, you will see a fantastic glow of blue and green specks similar to a field of fireflies. Many marine organisms such as bacteria emit light due to chemical reactions occurring inside of their bodies. Observing the underwater world at night is one of the most unique diving adventures you can encounter.
Going on a night dive begins with solid preparation.
Make sure you are familiar with the site you are going to dive. Choose a location you have dived before or scope the site out during the day beforehand. Knowing the layout will make navigation a breeze and will help you feel more comfortable throughout the dive. After you have picked a location, try to arrive just before dusk. It is much easier to gear up and plan out your route while there is still light. While you set up, conduct a thorough briefing with your buddy. Go over the dive plan and review all of the key hand and light signals you will be using. A circular motion with your light means “OK” while a side to side motion means “Attention”. Talking about these signals will ensure you and your team are on the same page. I also like to touch on buddy separation procedures. My dive partner and I have agreed to look around for no more than one minute before surfacing. Then we can reunite and continue our dive. Before you enter, mark your exit with a light or by using some prominent landmark. This facilitates an easy return by giving you a heading to swim for at the end of your dive. During the dive, try to stay shallow, stay close and go slow. Limiting your depth allows you to extend your bottom time and see all of the cool things night diving has to offer and you will have more fun knowing your buddy is nearby. Lastly, there will be a ton of new night life and going slow helps you take it all in.
There are some additional equipment requirements associated with night diving.
Of course, a good light is necessary to enjoy the dive. Dive lights come in water/pressure proof housings. They are rugged and capable of enduring the underwater environment. Over the years, light technology has improved drastically. Battery life has gotten longer and the bulbs are burning brighter than ever before. Your local dive shop can help you compare the myriads of different dive lights. One tip is to attach a bolt snap to your light just in case you want to clip it off. While you are using your light, be very careful not to shine your buddy in the eyes. He or she will not appreciate being blind for the next few seconds. Not only do you need a primary light, you also need a backup light. In case your primary light were to ever fail, your backup light allows to you make a safe controlled ascent. It is important to call the dive if any team member experiences a light failure. Other useful pieces of equipment are light sticks or marker lights. Light sticks can be attached to the tank valve. This makes you and your buddy easily identifiable underwater. Marker lights can be attached to an anchor chain or an exit point to help you find your way back home. Putting a marker light on your dive flag allows for quick reunification in case you and your buddy get separated. Finally, compasses are very important tools to help you navigate underwater. Make sure to get one that has a glowing dial. They are far easier to use when they stay illuminated after a brief flash of your light.
It’s okay to feel a little nervous before your first night dive.
As soon as you get into the water and see the unbelievable night life, you will understand why so many divers love it. Head on over to your local dive center and ask about the SDI Night/Limited Visibility Diver course. Your instructor can teach you the use of dive lights, and night diving techniques such as navigation, buddy system procedures, communications, buoyancy control, and interacting with nocturnal aquatic life so you can safely enjoy night diving.