Photographs from a sanctuary in the Democratic Republic of Congo show heartbreaking scenes as a park ranger comforts a gorilla which lost its parents to poachers.
Patrick Karabaranga, a warden at the Virunga National Park, comforts the orphaned mountain gorilla in the gorilla sanctuary park headquarters at Rumangabo in the east of the Democratic Republic of Congo.
The Virunga park is home to some 210 mountain gorillas, approximately a quarter of the world's population.
The four orphans at the sanctuary are the only mountain gorillas in the world not living in the wild, having been brought here after their parents were killed by poachers or as a result of traffickers trying to smuggle them out of the park.
Emmanuel De Merode, Director for Virunga National Park, said: "They play a critical part in the survival of the species."
The mountain gorilla is one of the two subspecies of the eastern gorilla.
There are two populations. One is found in the Virunga volcanic mountains of Central Africa, within three National Parks: Mgahinga, in south-west Uganda; Volcanoes, in north-west Rwanda; and Virunga in the eastern Democratic Republic of Congo (DRC) pictured here.
The other is found in Uganda's Bwindi Impenetrable National Park.
As of September 2015, the estimated number of gorillas remaining is less than 900.
They face a host of threats, including poaching, war and unrest, and habitat loss, and are dependent on conservation efforts to survive.