Ngogo and Kibale National Park

Kibale National Park is in southwestern Uganda.  It is the second largest remaining forest View of Kibale Forest, Western Ugandain Uganda and has the largest remaining population of chimpanzees in the country.  Kibale is a mid-altitude, moist semi-deciduous forest, with plant species composition and diversity intermediate between lowland and montane African moist evergreen forests.  The habitat follows decreasing north-south gradients in altitude (from 1,590m to 1,110 m) and rainfall.  A typical year includes two rainy seasons (September-November; March-May) and two dry seasons (December-February, June-August), although the amount and timing of rainfall varies considerably among years.  The vegetation comprises a mix of old growth forest (about 57% of total surface area), anthropogenic grassland, woodland, swamp forest, Papyrus swamp, and young forest at various stages of regeneration from human disturbance.

Seven diurnal primate species besides chimpanzees occur in Kibale: three guenons (redtailed monkeys, Cercopithecus ascanius schmidti; blue monkeys, Cercopithecus mitis stuhlmanii; L’hoest’s monkey, Cercopithecus l’hoesti), two colobines (red colobus, Procolobus rufomitratus tephrosceles; black and white colobus, Colobus guereza), baboons (Papio anubis), and grey-cheeked mangabeys (Lophocebus albigena).  Vervets (Cholorocebus aethiops) occur along the forest margin and in grasslands in some areas.  Nocturnal primates include pottos (Perodicticus potto), Demidov’s dwarf galago (Galagoides demidovii), and the eastern needle-clawed bushbaby (Galago inustus).  Leopards probably preyed on chimpanzees historically, but are now absent.  Kibale is home to a variety of forest ungulates, including several on which chimpanzee prey (blue duiker, Cephalophus monticola; red duiker, Cephalophus callipygus; bushbuck, Tragelaphus scriptus; bushpig: Potomochoerus porcus), and to diverse rodent, avian, and invertebrate faunas.  Elephants are abundant; their feeding on saplings and pole-sized stems and trampling of seedlings influences forest structure and, combined with rodent and insect predation on seeds and seedlings, can prevent forest regeneration in large gaps.

Ngogo is one of two research sites that the Ugandan Government  maintains in the park under the auspices of the Makerere Univeristy Biological Field Station (MUBFS). Ngogo has never suffered under commercial logging, however, evidence of human disturbance in even in the old growth forest, such as the presence of grinding stones on the forest floors.

Grinding stone on forest floor at Ngogo

In 1972, Thomas Struhsaker, then with the New York Zoological Society, established the Ngogo research area.  His primary focus was forest ecology and the behavioral ecology of red colobus monkeys, but he also studied the behavior ecology of redtailed monkeys and grey-cheeked mangabeys and the effects of logging.  Since then, many expatriate and Ugandan students, often mentored by Struhsaker, and many independent researchers have studied primate behavioral ecology, forest dynamics, rodent population biology, elephant ecology, and other topics.   Since 1995, David Watts (Yale University) and John Mitani (University of Michigan) have been co-directing the Ngogo Chimpanzee Project.