Check out this article posted in Scuba & H2O Adventure magazine. Destnation Scuba divers participated in a night dive put on by Jerry Portwood at Dive Shack USA at Lake Mohave:
No matter where you go in the world each scuba dive resort, liveaboard, or dive charter operation has a specific evening set aside for at least one night dive. You can dive a location several times during the day and see a boundless display of beautiful fish, but at nighttime, the dive site is completely different. As many of the fish find resting places and shelter from bigger fish and sharks, lobsters come out of their reef crevices along with dozens of night shift fish. Some fish may not retreat at all for the evening, but remain out in the open, only their entire personality changes for the evening hours.
A sculpin sailfish is a good example: During the daylight hours you can barely get close enough to photograph one, but at night you can rest a camera lens right next to them with out them swimming away. Nighttime is a good time for finding an octopus out making its dinner rounds or a turtle resting after an all day off reef jellyfish hunt. At night the substrate seems to come alive as heart urchins, nudibranchs, cone shells, conch shells, and other gastropods furrow though the sand. This is also prime time to see Spanish dancer nudibranchs swim though the water. At night, deep living fish, plankton, and the rare nautilus ascend in shallow waters for a few hours in search of food before descending back down thousands of feet before dawn. Squid come close to shore to lay eggs at night. To mention all the changes at night would take up several marine biology volumes, but we hope you get the gist of the idea that the nightlife show can truly be spectacular.
So where do you start your night dive journey? The best place is to start with is at your local dive shop and sign up for a night diving course which may take two to three dives depending on the dive agency, your past dives and level of training, and time of year. You could have a few hours of classroom setting followed by one or two night dives, especially if you are in Seattle in October when it gets dark at 4:30 p.m. and complete the course in a weekend or you could spread the course out over several weeks if the sun sets for only a few hours at a time as in Oslo, Norway in the summer time.
To do the dives you will need some additional equipment such as dive lights, and personal identification lights or glow sticks that attach to the back of your tanks and proudly proclaim by individual color, shine, or blink, which diver you are. The instructor or dive shop employee can help you select a dive light and back up lights: The more lights the better. We recommend getting the brightest most penetrating lights you can afford as it’s not much fun shinning your light up to view a single porthole when your buddy’s light is brightening up the rest of the sunken wreck. New lights have hundreds or thousand of lumens of power, and are better on battery life than most old watt calibrated lights. Surface signaling devices and Led surface signal buoys may also be part of your course items required or just plain desired, and therefore ultimately acquired.
Some of the many topics covered in the night diver course include planning for a night dive, which includes: Dealing with problems before they can happen prior to entrance into the water until after exit out of the water; this includes determining landmarks and lighting levels, or setting up your own shore lighting including large tripod style light stands. Proper methods for signaling a dive buddy without temporarily giving them night blindness due to shinning a bright light directly into their eyes will be covered. How to deal with disorientation will also be addressed in conjunction with how to deal with emergency procedures and how to monitor air consumption, control your buoyancy, and navigate in low visibility conditions using dive equipment with glow in the dark back grounds, automatic light backgrounds, and/or with the aid of dive lights. This all sounds technical, but it’s all fun to try out around the dive staff and fellow divers, especially at a site that you are familiar with from previously logged daytime dives.
One of the things that’s just plane fun to experience on a night dive is the bioluminescent outline of your arms and hands as they move through the water. For those learning night dive skills in warm tropical areas only a few tiny lights may appear as you swim and move your fins through the water, but a diver moving through the cooler waters of Seattle may have what appears to be a lighted up Christmas tree like outline as they move through the water.
Using boat lights and dive lights attracts small zooplankton which intern attracts tiny shrimp and larger zooplankton. This chain of events is what draws in the tiny pelagic sea horses and giant mantas off the islands of Hawaii. So you can easily see that becoming a night diver allows you access, to certain sealife that is rarely encountered by daytime divers.
We hope you will find that the skills you learn in your night diver course will be interesting to learn and fun to apply and once you become certified, you could, weather and job permitting, have at least another 365 chances a year to go diving. What could be better? Great night dives!
By Mike Hughes; photo by DeeDee Christensen
- 08 Dec 2014 12:34
- Written by Editor John