Passive & Active Search Techniques
Confinement
This is a tactic used to limit the area of the search. By establishing road
blocks, trail blocks and putting boundaries up that the subject should not cross
the area that must be searched initially is limited. It must be done early and
at a distance far enough from the point last seen or the Last known point that
the subject cannot have already passed by that location. This is of limited use
and is not often utilized.
Attraction
The use of lights, horns, voice checks, whistles, smoke or any other device for
visual or audible signaling can be used to alert the missing subject to the
direction they need to travel to find help. Most subjects found by hasty teams
are found with voice checks long before there is a visual sighting. The concern
regarding the use of attraction is the potential for drawing the subject into a
hazard if they try to travel to the signal at night when visibility is poor.
Trying to walk to a horn or a light the subject could walk off a cliff.
Track Trap Search
A track trap is a spot which will capture the fact that a person passed through the area. For example, if you walk along a beach, you leave footprints. Even if you "cover your tracks" there is still evidence that someone has passed through the area. There are many natural track traps, which include river and stream banks, trails with excessive mud or dust, thorn bush thickets and even sand pits.
However, in areas prone to lost person searches, like national parks, it is not unheard of for SAR teams to build track traps along major trails to help in search efforts. They might bring in a few loads of sand and place it in low spots along the trail. This sand pit captures a record of anyone passing down the trail. Then, if a search develops, the trained trackers in the area can immediately go to these known track traps and compare the prints against a known print of the lost person.
One "trick" tracking teams will sometimes use in a search is to go out and "rake" the known track traps before the lost person has a chance to cross them. This quickly eliminates many of the false tracks that the team might later have to rule out.
String lines
Spools of string are mounted on a backpack. As the search team member carrying
the pack walks through the area, the string unrolls leaving a very visible
trail. Other members following along tie the string at waist height on brush and
place paper arrows on the string pointing towards the base camp.
Line marking or trail blazing:
Surveyor’s tape, crepe or tissue paper used to mark edges of search lines and
paths taken by search teams. This marks the area searched for the subject to
follow out if he or she walks through the area later as well as assisting teams.
Planners can even color code the markers so that they know what has been done in
each area and by whom.
