Chancellor said his goal is to examine both legal and illegal forms of hunting.
These photos, from the first of three planned books on the subject, focus on legal hunting -- in which guides are hired to help track animals and supervise hunters -- and explore "the complex relationship that man has with animal, through the eyes of the tourist trophy hunter," Chancellor's website says.
During the project, Chancellor embedded with the hunters, sleeping on the floor of the bush and stalking animals with them, sometimes for up to two weeks. He said he worked to keep an open mind about hunting, even though he's a vegetarian.
Members of the hunting party walk until they find tracks and judge the size of an animal, Chancellor said. If it's deemed worthy of pursuing, the hunters will walk faster and catch up. But lions, for example, will realize they're being tracked and turn around to face predators. Chancellor doesn't carry a gun for protection.
Most of the people he followed were Americans, but "not necessarily that stereotypical brash, loud, slightly plump American." He trekked with the likes of mechanics who had saved for years and surgeons on vacation. "It's all about income," he said. Sometimes children were among the hunting parties.
Among the animals hunted in Africa are black rhinos, even though they're an endangered species. Under the Convention on International Trade in Endangered Species
, 10 black rhinos a year -- five each in South Africa and Namibia -- are allowed to be hunted for trophies. It's estimated that hunters pay hundreds of thousands of dollars for the right to take home a black rhino trophy, and the governments said the money is used to help pay for conservation efforts. Only adult male surplus black rhinos are to be hunted.
Arguments for trophy hunting as a conservation tool include sustainability, generating high revenue from few hunters and the ability to reduce illegal hunting, according to a 2008 report (PDF)
from the University of Pretoria, South Africa. And some countries such as Namibia have had success with increasing the numbers of its game through hunting and harvesting the animals, according The Economist.
"You have to meet in the middle," Chancellor told CNN.
The hunters are achievers, Chancellor said, and they're at the top of their game during the fatal moment.
As part of a tradition in many African tribes, the blood of a child's first killed animal is painted on the youngster's face. African guides will often follow the tradition when taking young trophy hunters into the wild. Different tribes paint various amounts of blood on the face; some children have it daubed on, while others have their entire faces painted, Chancellor said.
"The strongest portraits were directly after they've achieved, after they've killed the animal," Chancellor said of the hunters. "They're full of adrenaline; they're ecstatic."
But dealing with the deaths of these animals was hard for him to process.
"Seeing someone shoot Africa's iconic animals for the reason of having it sitting in the living room," he said, made it a difficult project for him.