Although both species of chimpanzees, the common
chimpanzee (Pan troglodytes) and the bonobo (Pan
paniscus) show a so-called fission-fusion social
organisation, they differ significantly in the details of
social relationships between and within genders. These
differences have been linked to ecological differences
between the species, habitats. Common chimpanzees living
in forested habitats were put forward as providing a link
between common chimpanzees in less forested habitats and
bonobos.
In this study, the Ngogo community of Kibale Forest in
Uganda was investigated to determine whether it is
justified to say that forest-living chimpanzees exhibit
characteristics in their social organisation which
resemble both the common chimpanzees in less forested
habitats and the bonobos. From January 1992 to June 1993,
focal animal samples on adult males, anoestrous and
oestrous females yielded data on party size and
composition, social interactions and time budgets.
Statistical analysis suggested that the Ngogo chimpanzees
resemble common chimpanzees from other habitats in party
size and composition, intra- and intersexual
relationships more than bonobos, whereas their time
budget resembles more that of bonobos. A comparison with
data from the literature suggests that intraspecific
variation of social organisation may be as great as
interspecific variation.
In the second part of the study, the impact of
habituation and tourism on the Kanyancu community of
chimpanzees in the Kibale Forest was monitored. From
February 1992 to June 1993, chimpanzees' initial
reactions to contacts with human observers were recorded
together with other factors such as numbers of observers
present and the method used to locate the chimpanzees. On
54 occasions with various numbers of observers (and/or
tourists) present, activity rates were recorded for the
observed individuals. Numbers of observers present (up to
5) had no impact on the chimpanzees, initial reaction,
and the only significant change in activity caused by
higher numbers of observers (up to 15) was an increasing
vocalisation rate. As visitor satisfaction declines with
groups of more than six to eight people it is suggested
that tourist groups viewing chimpanzees should be kept at a maximum number of 10 (including guides)