Although monitors are morphologically conservative, they vary in mass by five orders of magnitude. There is proportionately almost as much difference in mass among species of monitor lizards as there is between a mouse and an elephant. Sands constitute a natural event recorder, leaving a record of what creatures have moved past. Strong winds regularly dull and erase all tracks. Although it took quite a while, I eventually became fairly skilled at reading the record in the sand.
Tracks are difficult to see during mid-day when the sun is high or on overcast days.
Tracks are best seen by looking into the light. It is almost like becoming the lizard yourself. This allows one to move ahead quickly, cutting the track at intervals, to find the lizard rapidly. You can even tell the approximate age of a track by its crispness and whether or not other tracks, say those of nocturnal species, cross over the track in question. Nothing is much more exciting than finding a crisp new track less than an hour old, for you know that the maker of that track is close by at the end of the track.