Browsing by Author "Babaasa, Dennis"

Now showing 1 - 7 of 7
  • Thumbnail Image
    Item
    Census of the mountain gorilla Gorilla beringei beringei population in Bwindi Impenetrable National Park, Uganda
    (Oryx, 2006) McNeilage, Alastair; Robbins, Martha M.; Gray, Maryke; Olupot, William; Babaasa, Dennis; Bitariho, Robert; Kasangaki, Aventino; Rainer, Helga; Asuma, Steven; Mugiri, Ghad; Baker, Julia
    Mountain gorillas Gorilla beringei beringei are Critically Endangered, with just two small populations: in Bwindi Impenetrable National Park in south-western Uganda and the nearby Virunga Volcanoes on the borders with Rwanda and Uganda. A survey of the Bwindi population was carried out in 2002 and results were compared with the previous census in 1997. Our estimate of total population size increased over that period by c. 7% to 320 individuals and the structure and distribution of the population were largely unchanged. Signs of human disturbance were more common in 2002 than 1997, and gorillas tended to be found in areas of relative low disturbance. This suggested that disturbance could be a constraint on population growth and distribution but demographic stochasticity may also be responsible for the observed level of population change over a short time period. Other potential limiting factors, including habitat availability and disease, are discussed. While conservation activities in Bwindi have probably contributed to the stability of the population, strengthening of law enforcement and continued vigilance are needed to ensure the population’s long-term growth and survival
  • Thumbnail Image
    Item
    Forest Fire Prevention and Control in Bwindi Impenetrable National Park, South West Uganda
    (2000) Babaasa, Dennis; Kasangaki, Aventino; Bitariho, Robert
  • Thumbnail Image
    Item
    Gap characteristics and regeneration in Bwindi Impenetrable National Park, Uganda
    (African Journal of Ecology, 2004) Babaasa, Dennis; Eilu, Gerald; Kasangaki, Aventino; Bitariho, Robert; McNeilage, Alastair
    Before Bwindi Impenetrable forest, Uganda, became a national park in 1991, there was a high level of human activity in much of the forest, especially cutting of large trees for timber by pitsawyers. This created extensive gaps in this tropical Afromontane rain forest. We quantified and compared tree regeneration in three sites that were logged at different intensities. Gap sizes in Bwindi, even under fairly natural conditions are very large (mean ¼ 4460.1 m2). Logging further enlarged the gap sizes and had a negative impact on tree regeneration. The study shows the strong role of logging disturbance in promoting an alternative successional pathway, where the large gaps created by logging are in a low-canopy state dominated by a dense tangle of herbs, shrubs, and herbaceous or semiwoody climbers. We recommend periodic monitoring of gap size and tree regeneration in the gaps to ascertain the trend of recovery from past logging disturbance.
  • Thumbnail Image
    Item
    Impact of Water Harvesting on Kabiranyuma Swamp, Mgahinga Gorilla National Park, Southwest Uganda
    (2003) Bitariho, Robert; Babaasa, Dennis; Kasangaki, Aventino
    Kabiranyuma swamp is one of the rarest afromontane swamp habitats in Uganda. The swamp is a major source of water for the Kabiranyuma Gravity Water Scheme that supplies water to over 21,000 people around Mgahinga Gorilla National Park. The Institute of Tropical forest Conservation-Ecological Monitoring Programme together with the Development Through Conservation of CARE are monitoring the impact of the water scheme on the ecology of the swamp and sustainability of water extraction from the swamp respectively. Monitoring methods used are vegetation cover monitoring, fauna monitoring and hydrological monitoring. The vegetation cover monitoring was established by putting up a series of Permanent Sample Plots in the swamp to monitor changes in swamp vegetation over time and taking fixed-point photographs from the summit of Mt Gahinga for monitoring changes in swamp area cover. The fauna monitoring was established by carrying out a small mammal inventory within the swamp although successive inventories has not been possible due to insecurity in the park. Hydrological monitoring was established by CARE-DTC putting up a network of hydrological instruments to measure changes in water flows, water depth and rainfall. A probable negative impact of the water scheme on the plant ecology was manifested in a slight increase in Hypericum revolutum seedlings in the swamp. This is an indication that the typical “dryland” plant species may be invading the central swamp area, as is also seen in the fixed-point photographs. The major swamp vegetation is Carex spp that constitutes over 50% vegetation cover and has been constant over a three-year study
  • Thumbnail Image
    Item
    Links between anthropogenic perturbations and benthic macroinvertebrate assemblages in Afromontane forest streams in Uganda
    (Hydrobiologia, 2006) Kasangaki, Aventino; Babaasa, Dennis; Efitre, Jackson; McNeilage, Alastair
    Relationships between environmental variables and benthic macroinvertebrate assemblages were investigated among several sites that varied in disturbance history in Bwindi Impenetrable National Park, an Afromontane site in East Africa. Environmental variables were correlated with the level of past catchment disturbance – logging, agricultural encroachment, and present tourism activity. For example, sites in medium and high disturbance categories had higher values of specific conductance and lower water transparency than low disturbance category sites, these environmental variables may therefore act indicators of ecological quality of rivers. Environmental variables such as conductivity and water transparency were found to be good predictors of benthic macroinvertebrate assemblages, with anthropogenically stressed sites having lower diversity than the reference sites. Impacted sites were dominated by tolerant taxa such as chironomid and leeches, while ‘clean water’ taxa such as Ephemeroptera, Plecoptera and Trichoptera dominated at minimally impacted sites. Comparison of sites with different disturbance histories provided evidence for differences in benthic macroinvertebrate communities that reflect the state of forest restoration and recovery. We recommend quarterly monitoring of water quality to act as an early warning system of deterioration and tracking ecological recovery of previously impacted sites.
  • Thumbnail Image
    Item
    A Survey of Burnt Areas in Bwindi Impenetrable and Mgahinga Gorilla National Parks, S. W. Uganda The Fires Of 2000
    (Institute of Tropical Forest Conservation, 2001) Kasangaki, Aventino; Babaasa, Dennis; Bitariho, Robert; Mugiri, Ghad
    Fire has been one of the main management challenges and is considered one of the major long-term threats to forest biodiversity in Bwindi Impenetrable and Mgahinga Gorilla National Parks. In June, July and August 2000 fire outbreaks occurred the two parks. During September 2000 we carried out a survey of the burnt areas, which aimed at documenting the burnt sites and extent of damage caused by the fires. This was done as part of a long term monitoring programme to advise park managers about what could be done to prevent, halt or decrease incidences of fire outbreaks. The results show that approximately 0.2 square kilometers constituting 0.05% of the total park area was affected by fire in Bwindi Impenetrable National Park. The area affected was significantly smaller than that burnt in 1999 (2.64 square kilometers, 0.8% of park area); there has been a significant reduction in fire incidences in Bwindi in 2000 that we have attributed to the difference in the number of ‘rainy days’ in the ‘North sector’ and Buhoma and Ruhija, improved park boundary maintenance and increased sensitization of communities surrounding the park. However, the total numbers of ‘rainy days’ during the months of May to September were not significantly different between 1999 (139 ‘rainy days’) and 2000 (127 ‘rainy days’). In Mgahinga Gorilla National Park, 0.1 square kilometers constituting 0.3% of the Park area was affected by fire. However, we have no previous with which to compare 5 these estimates. In both parks illegal honey collectors caused most fires with a few spreading from community agricultural fields. On a positive note, the communities’ response to putting out fires was almost 100%. This shows an improved attitude of the communities towards protected areas. Given the fact that fire has become a regular component of the disturbance regime in the two parks, we recommend preventive measures such as public education and good public relations between parks and local communities, instituting and enforcing legislation on regulations for lighting fire in the park, establishment of early warning systems and the establishment and maintenance of a clear park boundary. We further advocate for the provision and maintenance of appropriate equipment and training of park staff in fire suppression measures. Lastly, since illegal honey collectors caused most fires, we recommend that park staff and all stakeholders in the management of the two Parks intensify sensitization of the communities on the dangers of fire in protected areas.
  • Thumbnail Image
    Item
    Weather Patterns At Ruhija, Bwindi Impenetrable National Park, South West Uganda
    (2000) Bitariho, Robert; Babaasa, Dennis; Kasangaki, Aventino