The lush forests in the western region of war-torn South Sudan are teeming with incredible biodiversity, but scientists haven't captured much photo evidence of the area's animal life -- until now.

DeeAnn Reeder, a professor of biology at Bucknell University , and Adrian Garside, a conservationist at Fauna and Flora International , set up 23 motion-sensing cameras in the remote forests in January. Five months later, they retrieved the images from each one.

Now, the researchers have examined those images -- around 105,000 in all -- and discovered chimpanzees, notoriously shy bongos and many other creatures roaming the area. Most surprising of all, they say, is the presence of rare forest elephants.

"This is an extremely important finding ," Reeder said in a statement. "Forest elephants are critically endangered, and have declined dramatically over the last two decades. Finding them in South Sudan expands their known range -- something that urgently needs further study because forest elephants, like their savannah cousins, are facing intense poaching pressure."

Forest elephants are smaller than savannah elephants and tend to inhabit densely wooded rain forests. Garside told the Associated Press that "this is by far the most northerly herd of forest elephants that anyone has seen in Africa."

Scroll down for an unprecedented glimpse into South Sudan's "forgotten forests."