Density and Habitat Use of Great Apes.
Although a country-wide survey has not yet
been undertaken in the Republic of Congo,
previous surveys of ape abundance suggested
that this country harbors relatively large
chimpanzee and gorilla populations. The
Goualougo Triangle Ape Project has conducted
extensive line transect surveys to estimate
the absolute abundance and habitat
utilization of chimpanzees and gorillas in
the intact forests of the Noubale-Ndoki
National Park, as well as in an adjacent
area that will be selectively logged in the
near future. These ape density estimates
serve as a baseline for this particular area
and comparative data set for similar
habitats in the region.
Evaluating the Impacts of Logging on Apes. To quantify the
effects of the timber extraction process, it is necessary to
collect data before, during, and after exploitation in a
specific area. This study design can be further improved by
simultaneously collecting control data in adjacent areas that
will not be logged. Such an opportunity exists in the Goualougo
Triangle located in the remote forests of the Republic of Congo.
Chimpanzees and gorillas coexist throughout the study area, some
of which was recently annexed to the Nouabal-Ndoki National
Park, while another section remains in the logging concession
scheduled for exploitation in the near future (see map).
The Goualougo Triangle Ape Project is employing a rigorous study
design and suite of research methods to determine the effects of
logging on apes. Repeated line transect surveys of ape signs are
being used to evaluate trends in ape abundance and distribution
within the logging zone adjacent to the Nouabal-Ndoki National
Park. We are conducting reconnaissance surveys in the logging
zone to identify social groups, collect behavioral data, and
monitor ape health. Baseline surveys were conducted in 2004
before the arrival of timber inventory personnel. The Goualougo
Triangle Ape Project is also monitoring ape densities in the
adjacent Goualougo Triangle, which serves as a control condition
for the logging zone.
Reducing the Impact of Logging on Apes. A significant number of
remaining chimpanzee and gorilla populations in Western
Equatorial Africa reside in active timber concessions, many of
which are within areas identified as being exceptional for the
conservation of these apes. Habitat alteration and human
disturbance can result in changes to the dietary regimes,
behavior, susceptibility to disease, abundance and distribution
of great apes, which may influence their short- and long-term
prospects for survival. The conservation outlook of these
endangered apes will improve significantly if forestry companies
are prepared to change their management policies in logging
concessions.
