Night Travel and Navigation For The Backcountry Hiker

By Blake Miller

The day started clear and bright as the hikers left the trailhead near Newport, Oregon.  The temperatures were to be moderate most of the day with slight cooling in the evening.  They pressed on determined to reach the summit before twilight.  After reaching the summit at dusk, the group started to make their way back to the trailhead as fog began to roll in.  Within an hour the darkness was becoming a problem and the safety of continued travel became questionable.

So what are some basic considerations for night time travel and navigation in the backcountry?

First, let us consider that we are not in a “lost hiker” scenario.  If lost, the best thing to do is to just stay where you are.  This makes the job much easier for the searchers. 

Further, recommendations are based on the concerns and issues of hiking when it is really dark, not during the period of a full moon with some ambient light.

One of the key factors in this situation is to have an understanding of the physiology of the eye. Our eyes are designed to provide optimal performance during periods of light.  The components of the eye (the retina, rods and cones) are arranged specific to their function.  The cones are the discriminators of fine detail and color.  Cones are the most effective in light, and are located near the center of the eye interior.  In complete darkness, a cones’ effectiveness is significantly reduced.  Rods are located on the periphery of our interior eye, are not fine detail discriminators and have a higher sensitivity to low light levels.  Rods are important to our night time vision.

In periods of extreme darkness your ability to see with clarity straight ahead is significantly diminished.  Rods play significantly in your night vision allowing you to observe objects but with reduced detail.  According an article by the American Optometric Association (see end of this article for more information) “To best detect small targets with the rods…the individual must look approximately 15-20 degrees to one side, above, or below…”  That impact is significant when you understand that to maximize your night vision you should turn your head from side to side consistently instead of keeping your focus straight ahead.

At night the term used to describe our ability to see is “night vision.”  Bright lighting is to be completely avoided.   Flashes of bright white light will ruin night vision.  Recovery takes about 30-45 minutes.  Low level white light and low intensity red light is better.

Care should be taken with the use of a GPS.  The normal white backlight function of the GPS receiver will damage night vision.  More frequent use of a compass while running a line of bearing as is using a low intensity red light flashlight may be prudent. 

Here are a few recommendations:

• If you absolutely must continue, first sit down and thoroughly examine the topographic map of your planned route.  Study the contours.  A detailed analysis is critical.  Your visual cues will be gone so you will need to establish new ones, larger objects.  Identify your lines of the land.  Lanes of extraction might present themselves on the map such as a power grid line, a road, a lake or an old jeep track.  Study the map.  Evaluate the terrain as best possible.  Openly discuss your line of movement with all involved so that you are all on the same page.
• Follow your trace on a map. Plot your position frequently.  Agree in advance how often you will do that.  Take your time with your navigation.
• For night time travel a consideration may be to have one person designated to read maps (with dim lighting) while others in the party preserve their night vision and lead the way.
• Remain on trail as much as possible.
• If you must bushwhack be careful of short cuts. Deep gullies and stream beds may be trouble. You don’t want to boulder hop in the dark.
• Move forward deliberately and cautiously.  Move more like you are stalking rather than down the easily trod dirt trail.
• Others might be moving too.  Be alert for bears, coyotes, cougars and in some areas perhaps wolves.
• A head lamp may be of more use than a handheld flashlight.  Two free hands are better than one.  Have extra batteries.
• Hiking poles or a walking staff is a fine idea.
• Sound travels well at night.  Be alert for audible clues to roads and running water.
• Guard your eyes as you move through brushy ground. If you don’t have a GPS and are navigating with just a map and compass it is very important that you start from a known position.  Navigating without getting position fixes from a GPS or by visual sighting is called dead reckoning.  Such navigation requires you to plot your compass heading and distance traveled.  Distance is accounted by pacing (counting your steps) as you move.  A good source of reference is www.landnavigation.org. 

Night time navigation is not something to be taken lightly.  From reviewing my books, US Army field manuals and conversations with experienced backcountry travelers it should be carefully considered and practiced before an actual outing.  You need to have confidence in your equipment (map, compass and GPS) and trust the information provided to you.  Such confidence is built up months and weeks in advance of your trip.  Practice your navigation at a local park with map and compass.  Consider geocaching for GPS users.  If you find yourself in a night time situation where you have any doubt, stop and prepare to spend the night right where you are.

For further reading about the physiology of the eye go to a report from the American Optometric Association (visit www.aoa.org/x5352.xml.) 

For more navigation- related SurvivalCommonSense.com tips and stories, click on the highlighted words:

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• Help the searchers find you in the wilderness.
• Is the Bushnell Backtrack the right choice for you?
• Improve your GPS skills now.
• Find your directions by the moss on trees?
• Simple survival tips for using a map and compass.
• Three maps you should carry in the wilderness.