Natural Sciences

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The Forest Birds of Kenya and Uganda
(Journal of East African Natural History, 1996) Leon, Bennun; Dranzoa, Christine; Pomeroy, Derek
Robust and rapid ways of assessing and monitoring forest biodiversity are increasingly necessary. To this end, we present a classification of forest birds in Kenya and Uganda into three simple categories: forest-specialists (FF species), forest generalists (F species) and forest visitors (f species). FF and F species, but not f species, are dependent on forests. Out of 479 forest birds in the two countries, 214 are FF, 156 F and 109 f species. Forest-dependent birds, and particularly forest specialists, are less widespread than forest visitors. Uganda has 420 forest birds compared to Kenya's 335, and a higher proportion of forest specialists: this reflects differences in forest structure and biogeography, rather than the area of natural forest. Using this classification allows species lists and densities to be interpreted more meaningfully. The number of FF species is an initial measure of a forest's relative conservation importance, while the proportion of FF, F and f species and their relative abundance will shift according to changes in forest structure.
Methods of studying the distribution, diversity and abundance of birds in East Africa—some quantitative approaches
(African Journal of Ecology, 1997) Pomeroy, Derek; Dranzoa, Christine
In this paper we compare the use of transect counts with a simpler method of investigating bird diversity and numbers, particularly in terrestrial habitats, both natural and non-natural. Transect Counts (TCs) have long been widely used, whereas Timed Species Counts (TSCs), which estimate relative abundance, are comparatively untried. We find that TSCs give results which are comparable to those from TCs in most respects, except that they can only be used indirectly for estimating population densities, and they give different measures of diversity. However, TSCs generate data on many more species much faster than do TCs and are therefore more cost-effective in most situations. In particular, TSCs are useful for community studies. We show, for example, that in natural habitats bird populations are positively correlated with the amount of woody vegetation, but not with rainfall. Diversity too increases with woody vegetation. Because TSCs are simple, more of them can be made for a given input of time, and hence more distributional data are obtained as an additional benefit.
Westphalian B marine bands and their subsurface recognition using gamma-ray spectrometry
(Yorkshire Geological Society, 1997) O'mara, Peter T.; Turner, Brian R.
Palaeogeographic reconstructions, marine band deposition and the variations of uranium enrichment in sediments enable marine bands to be divided into four types: (1) Namurian marine bands, which represent marine anoxic black shale events, with thick ammonoid acme phases that concentrate uranium; (2) Vanderbeckei marine bands have thin ammonoid acme zones and abundant benthos, resulting from shallower water depths and poorly developed anoxic events with negligible uranium enrichment; (3) Westphalian B/C marine bands are more marginal and have an abundance of land-derived plant fragments with adsorbed uranium, as well as uranium entrapped within phosphatic tests of Lingula; (4) brackish water Lingula beds with abundant terrigenous matter and negligible uranium response. This classification scheme provides a means of predicting the uranium response of individual marine bands which is attributed primarily to the type and amount of organic matter, and the salinity of the waters responsible for deposition. This approach allows marine bands to be recognized and identified in the subsurface from their gamma ray and spectral gamma response, and together with palynological analysis allows the marine band to be placed more accurately within the regional stratigraphic framework.
The survival of understorey birds in the Tropical Rainforest of Ziika, Uganda
(Journal of African Ornithology, 1997) Dranzoa, Christine
The forests at the shores of Lake Victoria had considerable attention from researchers during the 1970s. Ziika forest is one of the many small forest fragments that fringe the northern part of the lake. This 12 ha forest is surrounded by different habitats, giving it the appearance of a terrestrial 'island'. Birds were first ringed here from September 1970-July 1972. A follow-up was made in 1988-89, during which 186 birds from 27 different species were ringed. Five years later, survival rates were found to be significantly higher than the expected. Some species appeared to survive better than others. There are various assumptions made in estimating survival rates of understorey birds.
A Hominoid Genus from the Early Miocene of Uganda
(Reports, 1997) Gebo, Daniel L.; MacLatchy, Laura; Kityo, Robert; Deino, Alan; Kingston, John; Pilbeam, David
Fossils from a large-bodied hominoid from early Miocene sediments of Uganda, along with material recovered in the 1960s, show features of the shoulder and vertebral column that are significantly similar to those of living apes and humans. The large-bodied hominoid from Uganda dates to at least 20.6 million years ago and thus represents the oldest known hominoid sharing these derived characters with living apes and humans
A New Lorisid Humerus from the Early Miocene of Uganda
(Primates, 1997) Gebo, Daniel L.; Maclatchy, Laura; Kityo, Robert
An early Miocene (18-20 mya) distal humerus from Napak, Uganda, is the only element of the forelimb to be allocated to African Lorisinae. Its loris-like features distinguish it from other East African material that more closely resembles galagids. Tracing the evolution of the lorisoid body has been a difficult task due to the lack of good fossil material. Here, we add a single specimen to this poor record. This humerus helps to document the beginning of extant lorisid locomotor specialization and function.
The avifauna 23 years after logging in Kibale National park, Uganda
(Biodiversity & Conservation, 1998) Dranzoa, Christine
The bird fauna of logged and unlogged forest in Kibale National Park, western Uganda were studied and comparisons made. Species diversity and richness were higher in the logged areas. A single species, the Yellow-whiskered Greenbul Andropadus latirostris dominated in the logged compart- ment. However, the majority of individual birds found in the logged forest were generalist or forest- edge species. Over 84% of the forest interior specialist species that occurred in primary forest had recolonized or persisted in the logged forest; however, there were seven out of 48 understorey forest specialists that had not done so. Although there was moderate species overlap between the two habitats, the logged forest compartment had not fully recovered from logging after 23 years.
The Future of Tropical Water Resources: Using Palaeolimnology to Inform Sustainable Management
(National Fisheries Resources Research Institute, 2000) Hunt, L.H.; Nankabirwa, A.; Driessen, T.D.; Mills, K.; Lejju, J.B.; Ryves, D.B.; Jones, M.D.
Lakes are an important resource. They provide vital ecosystem services and employment for many communities worldwide. Maintaining lakes as ecosystem providers without damaging the lake ecosystems themselves, against a background of increasing human use of landscapes and climate change, requires careful and informed management. Key to such management is an understanding of how lakes will respond to ongoing and future changes in their catchments. Long-term monitoring, through regular measurements of lake chemistry for example, can help provide this understanding but such data are rare, particularly for tropical lakes. Using a palaeolimnological approach can provide an alternative to long term monitoring. This paper compares the information that monitoring data and lake sediment records can bring to an understanding of lake change in western Uganda. Water chemistry data show a general pattern to lakes with higher Chlorophyll-a and TP values over the last 15 years, although not all lakes follow this pattern. Sediment cores from Lakes Kamunzuka and Nyungu both show changes in diatom flora through the latter half of the twentieth century and increases in dry mass accumulation rate between c. 1980 and 2000. This study highlights the importance of a co-ordinated monitoring approach to provide the data needed to benchmark management decisions. The importance of understanding each lake on its own merits, from a monitoring or palaeolimnological perspective is also highlighted. Combined, these approaches provide an approach to inform management decisions to sustain lake ecosystems in a healthy state, for the benefit of all users.
Forest Fire Prevention and Control in Bwindi Impenetrable National Park, South West Uganda
(2000) Babaasa, Dennis; Kasangaki, Aventino; Bitariho, Robert
Implications of forest utilisation on bird conservation
(Journal of African Ornithology, 2000) Dranzoa, Christine
This paper gives a summary of the effect of selective logging upon forest bird communities. Some differences may exist from one region to another due to environmental as well as ecological factors. However, the general responses of bird communities to defined logging operations are predictable. A case study from Uganda’s Kibale National Park, is presented. Intensive mist-netting, counts and monitoring of breeding birds showed that species that are primarily adapted to exploiting forest edges, tree fall gaps and secondary habitats occurred and bred in large numbers in logged forest, but some species typical of forest interior were unable to adapt to logged forest. The long-term effects on the conservation of primary forest dependants are discussed.
Effect of gap size and age on climber abundance and diversity in Budongo Forest Reserve, Uganda
(African Journal of Ecology, 2000) Babweteera, Fred; Plumptre, Andrew; Obua, Joseph
A study of the e¡ects of gap size and age on climber abundance and diversity was carried out in Budongo Forest Reserve in Uganda. Data were collected from compartments N5, W21, B1 and B3. Stump records were used to locate and estimate the ages of 78 gaps. Sample plots 5 5m were set up in the gaps to assess climber abundance and diversity. Climbers were more abundant and diverse in gaps that were more than 400m2, 15 months old and had more than 25% canopy opening. Momordica foetida was the most abundant climber species occurring on stems, branches and crowns of seedlings and saplings. There- fore, in order to keep natural regeneration free from climber tangles and produce good quality timber, clim- ber control should be a major activity in tropical high forest management.
Postcranial functional morphology of Morotopithecus bishopi, with implications for the evolution of modern ape locomotion
(Journal of Human Evolution, 2000) MacLatchy, Laura; Gebo, Daniel; Kityo, Robert; Pilbeam, David
The large-bodied hominoid from Moroto, Uganda has until recently been known only from proconsulid like craniodental remains and some vertebrae with modern ape like features. The discovery of two partial femora and the glenoid portion of a scapula demonstrates that the functional anatomy of Morotopithecus differed markedly from other early and middle Miocene hominoids. Previous studies have consistently associated the vertebral remains with a short, stiff back and with orthograde postures. Although the proximal femur more closely resembles the femora of monkeys than of apes and suggests a moderate degree of hip abduction, the distal femur resembles those of extant large bodied apes and suggests a varied loading regime and an arboreal repertoire that may have included substantial vertical climbing. The femoral shaft displays uniformly thick cortical bone, beyond the range of thickness seen in extant primates, and signifies higher axial loading than is typical of most extant primates. The glenoid fossa is broad and uniformly curved as in extant suspensory primates. Overall, Morotopithecus is reconstructed as an arboreal species that probably relied on forelimb-dominated, deliberate and vertical climbing, suspension and quadrupedalism. Morotopithecus thus marks the first appearance of certain aspects of the modern hominoid body plan by at least 20 Ma. If the suspensory and orthograde adaptations linking Morotopithecus to extant apes are synapomorphies, Morotopithecus may be the only well-documented African Miocene hominoid with a close relationship to living apes and humans.
Weather Patterns At Ruhija, Bwindi Impenetrable National Park, South West Uganda
(2000) Bitariho, Robert; Babaasa, Dennis; Kasangaki, Aventino
Breeding birds inthe tropical rain forests of Kibale National Park, Uganda
(African Journal of Ecology, 2001) Dranzoa, Christine
A combination of trapping and foot surveys was used to assess the breeding status of birds in unlogged and logged sites in the tropical rain forest of Kibale National Park, Uganda. Breeding of forest edge and gap species was greatly enhanced by logging, whereas crevice and hole nesting specialist breeders were adversely a¡ected. Egg-laying periods corresponded to higher rainfall regimes at the nearby ¢eld station. The relevance of these ¢ndings to bird conservation is discussed.
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.
The inshore benthic macroinvertebrates of Lake Nabugabo, Uganda: seasonal and spatial patterns
(African Zoology, 2001) Efitre, J.; Chapman, L.J.; Makanga, B.
Lake Nabugabo, Uganda, is a lake of particular interest because of the unusual nature of its benthic macroinvertebrate community. In this study we quantified the spatial and temporal distribution of benthic macroinvertebrates within the lake with a focus on habitat associations in inshore areas. We focused on four inshore habitats: Nymphaea lotus/Nymphaea caerulea (water lily), Miscanthidium violaceum, Vossia cuspidata (hippo grass) and forest edge. The most notable characteristic of the Nabugabo fauna was the absence of bivalves and crustaceans and the scarcity of gastropods that made up only 1.8 % of the numerical abundance of the benthos. The numerically dominant taxa were ephemeropterans (77.7 %) and dipterans (11.1 %). Annelids (5.4 %), odonates (2.8 %) and trichopterans (1.3 %) comprised a much smaller component of the benthic assemblage. Total invertebrate abundance and the abundance of major taxa did not vary significantly across months, but habitat effects were evident. The water-lily habitat was very depauperate, which may reflect the low levels of dissolved oxygen near the sediments in this habitat. Lake Nabugabo is extremely poor in salts, mean conductivity in inshore sites ranging from 22.3 to 26.4 μS/cm and 22.6 to 37.9 μS/cm (K25) for surface and bottom waters, respectively. The low conductivity (low concentrations of ions) in Lake Nabugabo may limit colonization by molluscs and crustaceans that, with their calcareous shells or exoskeletons, may require water with a higher mineral content.
Regeneration of indigenous trees in Mgahinga Gorilla National Park, Uganda
(African Journal of Ecology, 2001) Lejju, Julius B.; Oryem-Origa, Hannington; Kasenene, John M.
This study examines the regeneration of indigenous tree species in the formerly encroached area in Mgahinga Gorilla National Park (MGNP), south-western Uganda. Before gazetting in 1992, MGNP had basically been agricultural land for well over 50 years. The distribution of exotic vegetationwas established using a Geo- graphical Positioning System receiver and indigenous vegetation was sampled by establishment of quadrats along transect lines.
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
A recent bottleneck in the warthog and elephant populations of Queen Elizabeth National Park, revealed by a comparative study of four mammalian species in Uganda national parks
(Animal Conservation, 2003) Muwanika, Vincent B.; Siegismund, Hans R.; Okello, John Bosco A.; Masembe, Charles; Arctander, Peter; Nyakaana, Silvester
Until 1972, Uganda’s national parks boasted of large numbers of large mammal species. Following the breakdown of law and order between 1972 and 1985, large-scale poaching led to an unprecedented decline in numbers of most large mammals in Uganda’s national parks. However, the extent of decline varied in the different parks across different animal species. We have investigated the genetic effects of these reductions in four mammalian species (the common warthog, African savannah elephant, savannah buffalo and common river hippopotamus) from the three major parks of Uganda using both microsatellite loci (for elephant and warthog populations) and mitochondrial control sequence variation in the warthogs, elephants, buffaloes and hippopotamuses. Queen Elizabeth National Park showed extreme reduction in nucleotide diversity for two species, the common warthog (π = 0.0%) and African elephant (π = 0.4%); no such decrease was found for the two other species, the buffalo (π = 3.7–5.4%) and hippopotamus (π = 1.7–1.9%), in the three parks. Nuclear microsatellite markers on the other hand showed high gene diversity in all populations in the common warthog (mean He 0.66–0.78) and the African savannah elephant (mean He 0.68–0.72). We interpret these results in terms of varying poaching pressure in the different parks, susceptibility of different species to poaching and differences in effective population sizes at the mitochondrial and nuclear loci
Diversity of rodents and shrews along an elevational gradient in Bwindi Impenetrable National Park, south-western Uganda
(African Journal of Ecology, 2003) Kasangaki, Aventino; Kityo, Robert; Kerbis, Julian
Small mammal species diversity in the major vegetation zones of Bwindi Impenetrable National Park is discussed in relation to altitude. Species richness of the smallmammals was found to decrease with an increase in altitude. The main factors accounting for the observed diversity are the wide altitudinal variation and a complex array of vegetation types. Sixty-seven species of rodents and shrews were found to exist in the Park; 47 of which were rodents and 20 shrews. Of these, 26 species are new to theBwindi Park list.Three species have probably notbeen described before. The study found 10 species of small mammals to be Albertine Rift endemics. Three genera are recorded in Uganda for the ¢rst time: Rwenzorisorex, Suncus and Paracrocidura. Five species are new records for East Africa. These are Crocidura stenocephala, Lophuromys rahmi, L. medicaudatus, Paracrocidura maxima and Hylomyscus aeta. Because of thehigh endemismof plants, butter£ies, birds and now of small mammal species, Bwindi forest is a unique biodiversity hotspot and is among the highest conservation priorities in the Albertine Rift.

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