THEY are among the last seven of their kind in the world – and they each have an around-the-clock armed guard as they roam in the shadow of Mount Kenya, Africa's second-highest mountain.
The four northern white rhinos are the most highly endangered sub-species of white rhino and the most precious of the 110 rhinos that live in the privately owned Ol Pejeta Conservancy.
Now a new weapon is to be used to fend off the poachers. Remotely piloted surveillance drones will track the animals' whereabouts and will give rapid warnings of human encroachment.
In one flight, the drones could cover 4046ha of the reserve. It will enable armed wardens to be dispatched rapidly when an animal is at risk.
The latest upsurge in poaching is fuelled by a growing demand for horns.
Ol Pejeta lost five rhinos to poachers in 2011. – The Sunday Telegraph