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Gorilla Journal 17, December 1998
Situation in the Parc National des Volcans
In September 1998, the first visit to the Parc National des
Volcans by staff of the Karisoke Research Centre for almost 14 months
was permitted and facilitated by military escorts. When the trackers began
making weekly visits to 3 groups of mountain gorillas, it was very reassuring
to find the population in apparently good health. There have been several
births. Only 3 of more than 80 gorillas remain to be accounted for. They
may not be missing, but we will need to make repeated visits to get opportunities
to see all individuals. The groups are observed in less than optimal conditions:
they have been in the bamboo zone, and visits usually last less than an
hour. One of the 'missing' adult females immigrated from the Susa group
in 1996, but was not well integrated into Pablo's group. We have yet to
establish whether she has returned to the Susa group.
Until recently, the most serious threats to the
mountain gorillas were poaching and habitat encroachment. Recent periods
of conflict could have had both direct and indirect impacts on the population.
Direct impacts may result from the presence of armed individuals from
both sides in the civil war: the dangers of being shot or shelled, and
the stress of confronting fleeing people or armed combat. Indirect effects,
however, are likely to pose more severe threats to the mountain gorilla
population. While patrols were still active we witnessed 4 gorilla casualties
resulting from antelope snares (3 infants and 1 adult female gorilla).
The infants recovered completely after veterinary intervention; a wire
snare cut off the fifth digit of the left hand of an adult female. Unable
to monitor them regularly, we feared that more gorillas would become accidental
victims of snares. Also, large numbers of people, both civilian and military,
have deposited potentially infectious faecal matter and other waste in
the forest.
Snares
The Parc National des Volcans is protected by Rwandan
and international laws, yet poaching of bamboo, wood and meat is a perpetual
problem. Karisoke anti-poaching patrols had removed 673 snares in the
first half of 1997. In June, Karisoke and government park staff (ORTPN)
daily patrols were suspended, and the local population took advantage
of the lack of protection for the park's flora and fauna. The intensity
of illegal activities became extremely worrying, with large quantities
of meat coming out of the park (mostly antelope) for sale in local markets.
During just 6 days in late July and early August, Karisoke trackers collected
140 snares, thus the likelihood of gorillas becoming snare victims was
high.
We have recently established that at least 96% of individuals in the 3
Karisoke groups are visibly in good physical shape. Apparently the same
is true of the 'tourist' groups. Fortunately, there has been no loss of
limbs or life to snares; this may be partially attributed to the ability
of certain gorillas to recognise snares. At least 2 silverbacks seem to
be aware of the danger posed by snares, and react strongly when a snare
is detected (unpublished observations). Having come through the last 18
months intact, it may be that the most serious health threat is the transmission
of human parasites and diseases to the gorillas.
Parasites
For decades, the Virunga Volcanoes region has been subject
to high human pressure because of the rate of human population growth
and the extremely fertile soil. Pressure on these volcanoes, indicated
by a human density of up to 400 people/km², has forced the gorillas
to limit their range to a small portion of these mountains, near the volcanoes'
summits. Close contact with humans has, however, increased in recent years.
Since 1994, as a result of the war and genocide in Rwanda, there have
been massive movements of refugees through the Volcanoes and Virunga National
Parks, followed by a military presence.
Fecal samples were collected from habituated gorillas
in Rwanda to investigate their evolving endoparasite fauna. Gorillas seem
able to tolerate certain species of gastrointestinal parasites without
manifesting signs of sickness. In 1997, veterinarians of the Mountain
Gorilla Veterinary Centre and researchers of University of Tennessee found
3 intestinal parasites not previously identified in gorillas, but known
to infect humans. The presence of these parasites may have resulted from
increased contact with human fecal matter or other waste. Such contact
is likely to have happened when large numbers of people were crossing
the park during the genocide in 1994. Infectious waste was probably left
uncovered in the forest. Due to the close genetic relatedness of humans
and gorillas, disease transmission is possible with potentially devastating
consequences.
The Mountain Gorilla Veterinary Centre has initiated
a comparative study in the Virunga National Park and may find further
evidence of human impact on the gorillas' health. Pressures on this protected
area have been enormous due to the presence of two major refugee camps
at the edge of the park from July 1994 to October 1996.
Since October 1997, human presence in the forest
has again increased significantly as a result of the renewal of war in
Congo. This could be disastrous for the gorilla population. There is,
therefore, a need to continue to closely monitor the health of this population
and, specifically, to periodically assess changes in the spectrum of parasites
carried by gorillas and variation in parasite loads. This would contribute
to the control of disease outbreaks and provide additional data for the
long-term management of this endangered primate.
Liz Williamson and Antoine Mudakikwa
Dr. Liz Williamson studied gorillas
in Gabon from 1984 until 1990, when she became the Director of the Nyungwe
Forest Conservation Project, Rwanda. She was involved in gorilla surveys
in Congo/Zaire and Cameroon in 1994 and 1995. Until the end of 2001 she
was the Director of the Karisoke Research Centre.
Dr. Antoine Mudakikwa has been working at the Mountain Gorilla
Veterinary Centre in Rwanda since 1995.
Volcano National
Parc overview
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