In pictures: Gorilla guardians

“Sometimes we will walk for eight hours and find nothing, but it is always worth it because you know the next day, or the day after that you will find the gorillas again,” Mr Kambale says.

“The longer we are able to work without interruption the better we can learn to know these wonderful animals.”

Around 1,100 wildlife rangers work in the parks of eastern DR Congo, protecting not only mountain gorillas, but also chimpanzees, forest elephants, rhinos and lowland gorillas.