[2][4] Typically, when working with living animals, a race track is prepared and covered with a substrate, which allows for the production of footprints, i.e. sand of varying moisture content,[1] clay [2][4] or mud.
[2] This poses an important advantage of working with living animals: changes in speed or direction, resting, slippage or moments of fright become visible in the produced tracks.
As an alternative, also tracks of free living animals can be studied in nature (i.e. nearby lakes) and without any special experimental setup.
In a typical experimental setup, the prepared foot is pressed into the substrate of interest, which again allows for the production of a footprint.
Other than in the methods previously mentioned, the experimenter has now the opportunity to regulate manually the pressure, direction and speed of foot touchdown.