60 Minutes is going to take you to one of the last places where enormous herds of elephants -- hundreds of them -- range free across the African savannah. It's remote, on the border of Chad and Sudan, and violent -- near Darfur, the scene of the civil war that became a genocide.
It wasn't so long ago, from 1970 to 1990, that nearly half the elephants in Africa, about 700,000, were slaughtered. Then, the species was saved by the world ban on the ivory trade. Since then elephants have done well in southern Africa. But in a different region, that knows no law, the hunt for elephants is on again.
In central Africa, where almost no one is looking, 60 Minutes ran into an ivory war.
60 Minutes spotted a great herd of mothers leading infants, foraging in the Zakouma Wildlife Reserve in southeastern Chad. It's a sight one might have expected in Africa 40 years ago, before the ivory slaughter of the 1970's and 80's.
But it's the start of the wet season, and water is luring them out of the protection of the reserve and into danger.
"This is like a refugee camp. And everything else around it for hundreds of kilometers, hundreds of miles has been exterminated," Mike Fay, a world-renowned biologist working with the Wildlife Conservation Society and National Geographic, explains.
"A refugee camp for elephants?" Pelley asks.
"Yeah. Basically," Fay says. "It's the only place left with wildlife."
Zakouma lies in central Africa. About 150 miles away is Darfur. Soldiers, rebels and bandits prey on ivory to fund their operations and satisfy their greed.
Fay came to Africa as a Peace Corps volunteer nearly 30 years ago. He's an explorer and naturalist who has made an alarming discovery. He spent two years counting Zakouma elephants from the air.
In his 2005 elephant survey, Fay says he counted 3,885 elephants.
The following year, there were only 3,050 elephants. "So we lost 835 elephants. Most elephants that die in Africa, the vast majority of them die prematurely at the hands of man," he says.
He proved it last year, capturing pictures of elephants killed only hours before. The poachers were still there. One man was even photographed shooting at Fay's plane.
"They always want more. So if they get ten elephants, they want 100. If they get 100, they want 1,000. And they won't stop until every single elephant is dead unless they meet resistance," Fay.
Resistance to poaching comes from Chadian park rangers, some of the toughest men we've found anywhere. There are 80 of them, mostly on horseback, patrolling the 1,200 square miles of the Zakouma refuge. The chief ranger is Nicola Talua.
"Most of your men are armed with AK-47s, this guy has a rocket propelled grenade, this guy up here has a machine gun mounted on his truck. This looks more like a war to me," Pelley points out.
"We have to be ready for war and stop the killing of elephants. The poachers wear no uniforms. They come here and open fire. In the face of such behavior, we are at war," Talua explains.