In pictures: Gorilla guardians

Mr Kambale has three sons and has been forced to flee his patrol post four times during his 12-year career as rebels set up camps in forests nearby.

He only returned to work at the end of February after the most recent attack.

Each day he rises at dawn from his small brick house at Bukima patrol post and heads out on patrol with two or three rangers.

They spend hours tracking gorillas, taking notes, keeping logs of sightings and monitoring the families.