Mountain gorillas of Virunga National Park, Congo

A park ranger looks at a silverback mountain gorilla in the Virunga National Park in eastern Congo. Virunga’s gorilla sector is home to 200 of the last remaining mountain gorillas.  (Jerome Delay / Associated Press)

A baby mountain gorilla is seen in the Virunga National Park, near the Uganda border in eastern Congo. Rebels and government officials tentatively agreed in November for the first time to work together in the gorilla sector. The agreement came comes just a month after rebels seized the park’s headquarters in Rumangabo.  (Jerome Delay / Associated Press)

A park ranger loyal to the rebel National Congress for the Defense of the People escorts visitors through the Virunga National Park in eastern Congo. The park headquarters had been seized by rebels on Oct. 26.  (Jerome Delay / Associated Press)

A silverback mountain gorilla travels through Virunga National Park, which has been caught up in Congo’s struggle between rebels and government soldiers.  (Jerome Delay / Associated Press)

Park rangers loyal to rebel forces make their way through Congo’s Virunga National Park.  (Jerome Delay / Associated Press)

Family members of returning park rangers unload their belongings on arriving at their homes in late November in Rumangabo. The rangers and their families had fled their homes after heavy clashes between armed groups broke out in and around the park.  (Roberto Schmidt / AFP / Getty Images)

A park ranger plays with his 9-month-old daughter after their return to their homes on in Rumangabo. Some rangers had stayed behind, and they insisted the gorillas were prospering under their care, with several recent births and the discovery, they said, of a new family.  (Roberto Schmidt / AFP / Getty Images)

The homes of park rangers at Virunga National Park. The newly installed park director Emmanuel de Merode, a longtime conservationist and Belgian national, agrees that the gorillas have generally fared better than people and other animals caught in Congo’s conflict.  (Roberto Schmidt / AFP / Getty Images)

Baby gorillas play near a female in a clearing on the slopes of Mount Mikeno in the Virunga National Park.  (Roberto Schmidt / AFP / Getty Images)