Lighting Up At Night In The Open Water
Swimming at night can be either an extremely fascinating activity to enjoy or an extremely frightful situation to overcome depending on the circumstances and the individual.
In either case, the global marathon swimming community using various illumination tools to help keep track of a swimmer at night:
Lamps, lights, illumination, glow sticks, strobe lights and LED lights are all used by swimmers, kayakers, paddlers and escort boats during open water swims at night.
Nick Adams has written an excellent article on this topic that covers anything and everything that a channel swimmer should know.
Adams explains the three different types of illumination that are used for English Channel swims: light sticks, disc lights and glow sticks.
The pencil-shaped light sticks are narrow battery-powered illumination that are pinned to a swimmer’s swimsuit or swim cap for safety reason during night swims or situations when visibility is poor (e.g., fog).
Disc lights are larger half-domed shaped, green-colored battery-powered illumination that is attached to the swimmer’s goggle strap and can be seen up to 5 kilometers away during a night swim.
The light comes with two modes: steady-on and flashing.
Examples include the Guardian dual function light that has two settings: stroke and constant. The first one clips on the goggle strap and the yellow one loops thru the garment tag on the back of your swimsuit or swimsuit straps (for women).
Ned Denison of Swim Ireland recommends them, “These are lighter and more comfortable that the light sticks. The cap one is tiny, weights nothing and is trouble free. The longer one tends to float and therefore you don’t get the feeling of the light stick bouncing on your bum and thighs.”
Glow sticks or chemical lights are another form of illumination that are pinned to a swimmer’s swimsuit and/or swim cap and can last up to 12 hours. The sticks are attached by a safety pin or wrapped within or around your goggle straps.
Outside of the English Channel, a variety of similar products are used.
Safety glow sticks (both chemical and battery-powered) are approximately 6 inches long and can be purchased in bulk from hardware, outdoor or marine products stores. While colors come in all different types (pink, purple, blue), green is the strongly recommended and preferred color no matter if you are in an ocean, bay, lake or river. Green is preferred for all the different types of illumination (light sticks, disc lights and glow sticks).
While everyone agrees that the disc lights are more powerful and more easily seen, some swimmers dislike the strobe (flashing) feature which they find distracting. Anne Cleveland who was the oldest person to complete a two-way of the English Channel and a veteran ocean swimmers who serves as an observer and support crew on many channel swims says, “I have noticed that it is easiest to see the swimmer with the battery-operated strobe light sticks when the light shining continuously, not blinking. You tend to lose sight of the lights behind the ocean swells and when it blinks it confuses what you are seeing.”
Some swimmers use a high-visibility waterproof LED light that can be seen nearly one kilometer in the distance. The Pelican Mini Flasher 2130 Personal Light is one model.
But like everything in the open water, experienced swimmers practice with their preferred illumination tools – and have backups – in order to make their night swimming a more pleasant and safe safe experiences. Dennison recommends, “Practice with these things, both in the pool and in the ocean long before your swim. Plus, carry an extra of each as well as spare batteries. Lastly, consult with your boat pilot and safety crew before you invest. Some pilots and crew recommend certain colors. Some insist on the strobes and others dislike the strobe setting because it is annoying to be blinked at over many hours through the night.”
Lynn Kubasek of the Catalina Channel Swimming Federation has used all different types in all different types of price ranges – and for practical purposes on the escort boat.
“The best one in my experience has been a battery head lamp. I use it to illuminate the swimmer’s feed bottles at night, read swimmers instruction bibles and going down into the bunk hull to get to my stuff while attempting to not wake everyone. We also had fun with the lights. A swimming electrical engineer friend made a goggle strap LED light that blinked my name in Morse code for my Catalina swim. I guess if I sunk to the bottom they would know it was someone named Lynn.“
Gary Emich of San Francisco uses the glow sticks that are activated when they are snapped in the middle. He and his fellow Bay swimmers tuck them underneath their goggle straps that is a common place to put them. Others in the Bay wear red or green waterproof lights on the back of their heads. But as Emich says, “We use them primarily so that on early morning, night and pre-dawn swims, our escort pilots can keep track of us. Fortunately, I’ve never had any creepy, slimy or stingy things attracted by the lights, but we stay away from strobe lights in the Bay as a white strobe can be mistaken for an emergency distress beacon by the U.S. Coast Guard.”
On the other side of America in Boston, Greg O’Connor says, “I have found that the green fluorophores emit a stronger light that lasts longer than other colors and use glow sticks, but they do have a negative environmental impact because it is a disposable item and one of the chemicals, phenol, is toxic. The fluorophores that are in the blue range of the spectrum are not good for night swimming. The color does not cut through the dark very well. The glow sticks are activated by a chemical reaction and are temperature sensitive. In warm water, the reaction is faster and brighter and in cold water it is dimmer, but longer. Princeton Tec makes a strobe flasher that I have tried for night swimming, but I prefer the glow sticks.”
Elaine Kornbau Howley, a Triple Crown swimmer, also uses a variety of illumination, “In most of my training, I use the basic plastic ‘snap and glow’ glow sticks that I tuck into the back of my goggle strap and attach one to the back of my suit. I also use the small round reusable lights that many English Channel swimmers use, the Guardian brand, is tied to my goggle straps.”
Leslie Thomas of Swim Art uses glow sticks and night gear strokes on her night swimming expeditions in San Francisco Bay and Lake Tahoe. “My swimmers wear 10-inch long skinny glow sticks [shown here]. We stick them in the goggle straps. These can also be made into bracelets. The thicker emergency-style ones that you would get at REI or a hardware store are safety-pinned to the swimsuit straps and/or swimsuits themselves. We use them on our group swims because they are cheap and fun and we can play with them afterward.”
“I also like the waterproof Night Gear Adventure Light strobes that can be threaded through goggle straps,” echoing the advice of Adams in the English Channel. “These are much more visible and work great, but they are more pricey. I use these personally and I have my kayakers use these for dark swims when they strap them to their boats.”
Rob Kent of the Lake Ontario Swim Team and host of L.O.S.T.’s Mid-summer Night Swim under a full moon in August keeps its simple.
“As far as swimming in Lake Ontario at night, we just use glow sticks. Cheap and easy to get a hold of. Just about any dollar store has them. Now is a good time of year to stock up, or actually right after Halloween it will be. We are lucky because there are no creepy-crawly things in Lake O that are attracted to the light. That is one advantage to lake swimming, although back in the old days there were eels that would freak people out, especially at night. The fact that we don’t have any sharks or jellies or eels or anything else is a small consolation when it comes to convincing people to swim in the dark. More just a fear of the unknown. Marathon swimming is very much a psychological event and nothing proves that point more than when you ask a bunch of swimmers if they want to go open water swimming at night.”
Illumination is also used for and by support kayakers and escort crew. Kayakers often use head lamps on swims. But in some cases, the head lamps can cause problems for the swimmers. Forrest Nelson, an accomplished Triple Crowner who has served on dozens of night swims as an observer and support crew, cautions, “During most night swims, the swimmer’s eyes are fully dilated. One flash of a bright head lamp can cause a swimmer (or a escort boat pilot or the other kayaker) to temporarily lose their vision. One solution is to use head lamps with red filters.”
Sometimes, with all the new technology from disc lights to GPS, we can forget that only a few years ago, marathon swimmers plied their trade without such equipment. “Swimmers from just a few decades ago never had head lamps or chemical sticks,” recalled Nelson. “I can’t imagine the stress on the support team to keep watch on an unlit swimmer in the middle of the night or with dense fog.”
But they did it and lived to enjoy telling their adventures to the later generations.
One effect of using these forms of illumination is that they can attract fish and other marine life depending on where you are swimming. In the case of the recently successful Ventura Deep Six Relay along the Southern California coast, Jim McConica, one of the swimmers said, “The fish were nibbling on my feet.”
One Ventura Deep Six Relay swimmer at night can be seen here. For some, this is an interesting experience. For others, it can get be downright creepy and/or immensely irritating.
In the Tsugaru Channel in northern Japan, the escort boat pilots used to shine their lights on the swimmers…until the swimmers realized that the lights attracted a sea of squid to the surface of the water. While swimming through squid is not as disconcerting as swimming through jellyfish, the constant contact with squid is something that takes a bit of getting used to.
For a swimmer who has swum among many sharks throughout the Pacific Ocean, Anne is cautious about placing a spot light on the escort boat shining on the swimmer. “A spot light from the escort boat shining on the water can bait fish, which leads to bigger fish. That actually happened some years back in the Catalina Channel and the swimmer had to be pulled when a large mako shark began darting about quickly close to the swimmer.”
But after the safety aspects are taken care of and you become comfortable swimming in the dark, there are several places around the world where the bioluminescence absolutely enthralls marathon swimmers. As Elaine recalls, “My best experience with night swimming was across the Catalina Channel. I was so enchanted with the bioluminescence I forgot it was dark out at all.”
Open Water Swimming strongly recommends that parallel lines of 3 – 5 glow sticks are adhered to the sides of a kayak or paddle board during night sights. Having a line of glow sticks on the kayak makes night swimming so much more easier for the swimmer, especially in rough conditions.
Photo of Zina Deretsky.
Copyright © 2008 – 2021 by World Open Water Swimming Association
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