When Dodi, an 18-month-old female bloodhound, first saw the elephant carcass along the Ishasha River in the eastern Democratic Republic of the Congo (DRC), she took one sniff and ran. She was skittish for a reason – this was her first encounter with a corpse. But she would certainly see others. Dodi is one of five purebred bloodhounds being trained to track poachers in Virunga National Park, one of the world's most dangerous protected areas, and this was the team's first mission.

Park ranger Christian Shamavu, Dodi's handler and chief of the park's new canine unit, calmly reassured the dog until she regained her wits and found the scent left by whoever had killed the elephant and hacked out its tusks. Within minutes, Dodi was leading Shamavu across the river, past herds of grazing kob and topi antelope, to a nearby village.

Africa's oldest national park, Virunga is 4,847 square miles of active volcanoes, jungles, and savannahs along the eastern rim of the Congo Basin. The area houses more than half the biodiversity of sub-Saharan Africa, including lions, hippos, migrating arctic birds, and nearly a third of the Earth's remaining 720 mountain gorillas. It's also at the epicenter of "Africa's Civil War," a two-decade, multicountry conflict that's killed more than 5 million people.

Amid this chaos, illegal poaching has always been a common source of income. Now, it's become an epidemic, as demand for black-market ivory has increased, due in part to China's new position as an economic superpower and its taste for ivory trinkets. Twenty-three of Virunga's roughly 350 elephants were killed in 2011 and the first eight months of 2012. The problem is not limited to Virunga: Despite years of conservation efforts, the number of poachers has increased exponentially on the continent. In March, 22 dead, tuskless beasts were found in Garamba National Park, 300 miles north of Virunga in the DRC. All told, poachers slaughtered more than 10,000 elephants in 2011.

In a park as large as Virunga, it's almost impossible to catch those responsible. "Being able to apprehend poachers, or at least figure out which direction they went, is crucial," says park director Emmanuel de Merode. Locating lost and injured rangers and visitors is another major priority. Last year, a ranger was shot in the leg during an ambush, and it took a response team 24 hours to locate him. He died from loss of blood, a mere 100 yards from where they were searching.

The Virunga rangers are essentially an undersupplied and outnumbered army caught between government troops, rebel militias, armed bandits, and hundreds of thousands of refugees displaced by the fighting. Between 1996 and 2011, 132 rangers were killed. Each earns $170 a month for a job so dangerous the park recently set up a widows' fund to keep families afloat.

De Merode first got the idea to use bloodhounds from a fellow park warden in Kenya, where they're used for border patrol. In March 2011, Marlene Zähner, a Swiss veterinarian with two decades of dog-training experience, agreed to lend her services. She arrived with the young bloodhounds, ready for the difficult task of training the rangers.

"Hounds are born to track," Zähner says. "It's the handlers who often need the most training." This is especially true in rural Africa where canine pets are uncommon; most of the Virunga rangers had never even seen a bloodhound before. First, the men had to learn what a dog was and how to properly treat one. Zähner selected five worthy rangers and, once they were comfortable, began laying scent trails through grasslands and brush. They then tracked down runners who hid in the brush and inside concrete structures. Along with a security force and police canine instructors, Zähner showed the rangers how to handle crime scenes. The hounds are trained only to find people, not to apprehend them – an eight-man security force trails the teams, protecting them from suspects who are often hostile and heavily armed. Though skeptical at first, Zähner was impressed by the rangers' progress: "They're the most professional and devoted people I've ever worked with."

The young dogs have had to adjust to as many new experiences as the rangers, from unfamiliar foods like cassava and rice to the sounds of gunfire and the barking baboons that gather in front of their kennel. For all this, though, Zähner says they receive better care than most dogs in the U.S. and Europe, with round-the-clock attention and affection. One of the program's greatest benefits is that the dogs' presence makes life more bearable for the rangers.

De Merode hopes to have the five teams patrolling the park this fall. But such plans tend to evaporate in a country that placed last in the UN's 2011 Human Development Report. As of August, tourism was halted, and there were at least four militia groups inside park borders, one of which has killed 11 rangers. De Merode nonetheless remains positive that the teams can help prevent park atrocities, and the hounds and rangers will continue their education.

It's paying off: In the savannah near the Ishasha River, Dodi followed the trail for miles until she and Shamavu were called back and the security team went in. Near dawn, they traded fire with a group of suspected poachers, who eventually fled. They left behind four rifles, none of which will ever kill an elephant, or a person, again.