Introduction to Human Tracking
By the time we are called to a search, the Rangers or initial responders will have established the place that the subject was last seen or known to be. The "Point Last Seen" is often abbreviated - PLS. Identifying a place last seen and a direction traveled by the subject is very important in that it helps to concentrate the search area as shown in Figure 1.
The initial responders will also have developed the most complete description of the lost subject(s) as possible. That description will include the subject's sex, age, size, weight, hair color and clothing worn. With luck, the description will include a description of the type of shoe the subject was wearing and maybe even a drawing of the sole or lug pattern. A description of the shoe type and size is helpful to understand what type of track to look for in the field.
In a more formal tracking training session the description of the footprint would include students making a detailed drawing of the print and measuring the print as follows:
A) Overall length
B) Length of heel
C) Width of the ball of the foot
D) Width of the heel
(See Figure 2)
The reasons to make a detailed drawing of the footprint include its possible use as evidence and in helping you to remember it yourself so you can communicate information about it to others.
Once a set of tracks is found in the field the tracker can measure the stride interval (E, Figure 2), which is the distance between the tip of the toe of the first print and the back of the heel in the following one. The stride interval can be marked on a "tracking stick" and then measured repeatedly to help find the most likely location of next footprint. This area is called the "Prime Sign Area."
Use of the tracking stick is shown below in Figure 3.