 As well as allowing in-depth study of animal behaviour and migration, the high-resolution tracks available from a GPS-enabled system can potentially allow for tighter control of animal-borne communicable diseases such as the H5N1 strain of avian influenza.Collar attachment is the primary attachment technique where the subject has a suitable body type and behaviour.Tracking collars would normally be used on the animal's neck (assuming the head has a larger circumference than the neck) but also on a limb, perhaps around an ankle.