We are evaluating GPS collars to be used to monitor the animals in the field. The company FollowIT has constructed a foot mounted version of the collar that suits the black rhino, which has a narrow wrist and a think neck. This has been in use at the rhino Namakula at Kolmården Zoo for more than a year, with good results.
As usual for GPS, there are frequent large outliers due to multi path of satellite signals, and position noise that might increase due to foliage and other scattering effects. The animation below shows the movement over a few hours, where we have processed the GPS positions with a filter, which also estimates the heading of the rhino.