Number of times a microchip number could be followed through the system, where the connecting lines indicate the different permits the same microchip number has been reported on (i.e., import to the Free State, captivity, transfer, euthanasia, export from the Free State, or CITES exports). The numbers on the y-Axis indicate the number of times in which the combination has been identified. The colours indicate whether the combination is theoretically possible (blue), or improbable (red).