Watching habituated chimpanzees is one of the world’s most thrilling wildlife experiences. Chimps are found in the forests of Equatorial Africa from Tanzania to Gabon, with one of the largest populations being in the Democratic Republic of the Congo. The total number has declined precipitously over the past two decades — by 90 percent in the Ivory Coast alone — as a result of deforestation and the construction of logging roads that make it easier for poachers and hunters to access the interior.

Between 150,000 and 250,000 are now estimated to be left in the wild. Most of them are unused to people and extremely shy. But a few groups have been studied by scientists for decades and have become completely indifferent to the presence of humans. The most famous group is the Kasakela community in Tanzania’s Gombe Stream National Park, at the northeastern end of Lake Tanganyika, where Dr. Jane Goodall began her pioneering research in 1960.

The only place to stay in the area is the relatively simple Gombe Forest Lodge. On my recent trip to Rwanda, I watched chimps in the Cyamudongo forest and stayed in the comfort of nearby Nyungwe House. The chimps were unafraid and easy to observe through binoculars.