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The community structure and population density of birds was studied at 10 sites in three broad woodland types in the lowveld of Swaziland. Birds were surveyed on a monthly basis at 12 locations per site using a standard point count technique. Each site was surveyed over a 12-month period. Vegetation characteristics of each location were recorded. Both cluster analysis and non-metric multidimensional scaling using bird densities, grouped the sites into two main habitats: riparian and non-riparian. The non-riparian habitat was further divisible into Acacia savanna and broadleaved woodland. A similar classification was obtained using vegetation characteristics. Principal components analysis (PCA) of the vegetation characteristics was conducted. The first axis (accounting for 57.7% of the total variation) represented variation in tree cover below 3.5m and grass cover above 0.25m. The second axis (24.8%) represented variation in tree cover above 3.5m and grass cover below 0.25m. These two axes accounted for 82.5% of the total variation. In general, the Acacia sites had lower tree cover and high grass cover, the broadleaved woodland sites had higher tree cover below 3.5m, and the riparian sites had the highest tree cover. Acacia savanna recorded the highest species richness of birds (128 species) with lower numbers recorded in riparian (101) and broadleaved woodland (94). A total of 161 species of birds was recorded across all sites, of which 48 species were recorded on fewer than four occasions, and 51 species were recorded in all three habitats. Of the remaining species, 14 species were confined to Acacia savanna, 14 species to riparian, and two species to broadleaved, woodland. Broadleaved woodland supports adepauperate, but indistinct, avian community compared to that of Acacia savanna; riverine forest, in contrast, supports a different set of species.Ostrich 2005, 76(1&2): 45–55

Population density and community structure of birds were studied at three sites in riverine forest in the lowveld of Swaziland. Birds were surveyed monthly using a standard point count technique. A total of 101 species of birds was recorded. Species richness at the three sites ranged between 70–76 species. Population density was similar at the three sites and ranged between 24.0–31.2 birds ha -1 . Biomass of birds was also similar at the three sites. Resident birds accounted for 74% of all species, but made up 97% of the individuals and biomass. There was a relatively large number of vagrant species, but they only accounted for Acacia savanna and broadleaved woodland in Swaziland. (Ostrich: 2003 74(3&4): 173–180)

International Rice Research Institute, DAPO Box 7777, Metro Manila, 1301, Philippines. Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK. Julius Kuehn Institute, Federal Research Centre for Cultivated Plants, Institute for Plant Protection in Horticulture and Forests, Toppheideweg 88, 48161 Muenster, Germany. Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, B.C. V6T 1Z4, Canada. Department of Biological Sciences, University of Swaziland, Private Bag 4, Kwaluseni, Swaziland. Corresponding author. Email: g.singleton@irri.org

The Lower Usuthu River Basin is set in the lowveld of Swaziland. The predominant vegetation types are mixed broadleaf woodland in the western lowveld and Acacia savanna in the eastern lowveld. The mammalian fauna of the Lower Usuthu Basin has been poorly documented. The study set out to survey mammals of the Lower Usuthu Basin using appropriate sampling techniques. A total of 45 species of mammals were recorded, or presumed to occur, in the study area, of which 10 species are of special conservation status both within Swaziland and in the southern african region. On Swazi Nation Land, species diversity and population sizes of mammals, especially the antelopes, were very low. Large-scale reduction of habitat may affect the conservation status of many mammals in the Lower Usuthu Basin. UNISWA Research Journal of Agriculture, Science and Technology Vol. 4 (1) 2000: pp 55-61

Resolving species limits within the genus Miniopterus has traditionally been complicated by the presence of cryptic species with overlapping morphological features. We use molecular techniques, cranio-dental characters and tragus shape to describe a new species of Miniopterus from Mozambique, M. mossambicus. Miniopterus mossambicus shows > 12% divergence in cytochrome-b sequence from its nearest congeners (the Malagasy M. gleni and M. griveaudi) and > 15% divergence from the morphologically similar M. natalensis, M. fraterculus and M. minor (all of which occur in southern and eastern Africa). There is considerable overlap in cranio-dental characters of the southern African species, particularly M. natalensis and M. mossambicus. However, tragus shape and multivariate comparisons of skull measurements can be used to separate these species. Based on morphological comparisons of museum specimens, this species may also be present in neighbouring Malawi and Zimbabwe, suggesting that it is probably distributed widely in south-central Africa.

Context Rodent pests severely affect crop production, particularly in monocultures where one or two rodent pest species dominate. We predict higher species richness of native small mammal species in more heterogeneous mosaic (crop–fallow–bush) subsistence agro-ecosystems in Africa. Conservation and agro-ecological imperatives require that such diverse natural communities should be maintained and may benefit crop protection through limiting domination of pest species. Ecologically based rodent-management alternatives to rodenticides are urgently required and one such method (community trapping) is herein advocated. Aims To provide baseline information on rodent and shrew communities in agro-ecosystems in three African countries and to demonstrate efficacy of ecologically based rodent management (EBRM) in Africa (e.g. community household trapping). Methods Removal-trapping in a variety of agro-ecological habitats provided accurate small-mammal species lists. Intensive kill-trapping by rural agricultural communities was carried out experimentally where the efforts of communities were scientifically monitored by kill-trapping to measure impact on rodent numbers and the levels of post-harvest damage to stored grains. Key results Our study revealed a high diversity of endemic species in agricultural habitats in Tanzania and Namibia (but not Swaziland) and the existence of undescribed and possibly rare species, some of which may be at risk of extinction from unchecked habitat transformation for agriculture. Treatment-control studies showed that communities in three African countries could effectively reduce pest rodent populations and rodent damage by intensive trapping on a daily basis in and around the community. Conclusions Community trapping reduced pest rodent populations and damage to stored grains. Unlike the use of indiscriminate rodenticide, this practice is expected to have a negligible effect on beneficial non-target rodent and shrew species. Implications Ecologically based rodent management approaches such as community trapping will conserve beneficial non-pest rodent communities and ultimately improve crop protection.

Context The multimammate mouse, Mastomys natalensis (Smith, 1834), is an important agricultural pest in southern and eastern Africa where it can cause significant crop losses. Mastomys natalensis is known to consume a variety of food in response to the availability of food items. However, it is currently unknown whether maize crop growth stages affect the spatio-temporal diet of this species. Aims We examined the foods consumed by M. natalensis in different habitats and seasons in central Tanzania and Swaziland. Methods Diet was investigated in Tanzania in four different habitats (woodland, vegetable gardens, maize fields and fallow land) during different maize crop growth stages between March 2008 and February 2009. In Swaziland, this was conducted in three habitats (fallow land, cultivated fields and pristine land) during three crop growth stages (pre-planting, vegetative stage and post-harvest) between March 2008 and April 2009. Micro-histological examination of undigested fragments from the stomachs of trapped animals was made whereby the preserved stomach content was placed in a Petri dish and sorted using a 25× or 50× magnification binocular stereoscope. Stomach contents were identified as: grain and/or seeds (both grasses and maize), plant material (roots, stems and leaves), invertebrates, pods of seeds, fruits (vegetable fruit such as tomato), animal hairs and unidentified matter. If necessary, a lugol solution was used to determine the presence of starch for maize and grass seeds or grains. Key results In both countries, grain predominated in the diet of M. natalensis. Statistical analyses showed that there were no differences due to seasons or habitats. Therefore, the percentage volume and relative importance were the same across habitats and seasons in both countries. Conclusions Our findings highlight clearly that M. natalensis is a generalist species feeding on available resources depending on the season and the habitat. Its preference for grain may account for its abundance in maize plantations and confirms it as one of the major pests in crop plantations, especially grain. Implications This information offers a useful tool for determining the pest status in different habitats and/or seasons. The findings of this study have implications for agriculture and conservation.

Context Rodent pests can have severe impacts on crop production in sub-Saharan Africa. In particular, the multimammate mouse Mastomys natalensis severely damages agricultural crops in southern and eastern Africa, leading to significant losses. Both its population ecology and breeding biology have been studied in agricultural and natural habitats. Population numbers erupt depending on the timing and amount of rainfall and may reach plague proportions, especially in agricultural settings, where it may become a serious pest. However, the ecology of this species, in particular its interactions with other species within the context of human settlement, is poorly understood. It may occasionally enter houses, but the degree to which it does so and the factors influencing this movement are not known. Aims We investigated the relationship between Rattus spp. and M. natalensis entering buildings in an agro-ecological setting. We predicted that M. natalensis would enter houses more readily when food availability was lowest in the surrounding fields, and when the larger Rattus spp. were absent. Methods We followed 40 individuals of M. natalensis in Swaziland and Namibia by radio-telemetry. Mice were captured in maize fields within 50 m of a homestead and fitted with radio-transmitters at three different times corresponding to different stages of crop development: pre-harvest, post-harvest and pre-planting. To corroborate the findings of the telemetry study, a non-toxic marker, rhodamine B, was mixed with standard bait and left at bait stations inside houses in 10 homesteads in Swaziland and Tanzania. Key results Mice remained in the fields during the entire period of study in Swaziland, but entered buildings in Namibia during the post-harvest stage, which may represent a period of food shortage for these mice in the field. Rodents captured after baiting with rhodamine B demonstrated that Rattus spp. predominated within the houses. A small number of rhodamine B-marked M. natalensis were captured outside the houses, the proportion declining with distance away from the houses. Conclusions These results suggest that in a typical rural African setting dominated by subsistence agriculture, Rattus spp. (when present) competitively exclude the smaller M. natalensis from entering houses. Implications Interactions between rodent pest species may be important in determining which rodent species enter houses in rural African landscapes. Consideration of such interactions may play an important role when developing pest management strategies.

Mastomys natalensis, the multimammate mouse, was live-trapped on six grids varying in vegetative cover and vegetation height between June 1996 and May 1997. There were three treatments, each with two replicates: reduced cover, reduced cover with supplementary food and control. The numbers of M. natalensis on the grids with reduced cover were lower than those on the control. Food supplementation, however, significantly increased numbers on one of the replicates. There were also significant differences in the number and proportion of resident and adult mice among the grids. The grids with reduced cover supported a population with a lower number and proportion of adult and resident mice than those on the control. In contrast, despite the reduced cover on the food supplemented grids, the population on one of the these grids exhibited a higher number and proportion of adult and resident mice than those on the control. Mastomys natalensis appears to select patches with greater vegetative cover but it will abandon cover in the presence of an abundant food source.

Investigating the ecology of long lived birds is particularly challenging owing to the time scales involved. Here an analysis is presented of a long term study of the survival and population dynamics of the marabou stork (Leptoptilos crumeniferus), a wide ranging scavenging bird from Sub-Saharan Africa. Using resightings data of tagged nestlings and free flying birds we show that the stork population can be divided into three general life stages with unique survival probabilities and fecundities. Fecundity of the storks is inversely related to rainfall during their breeding season. Corroborative evidence for a metapopulation structure is discussed highlighting the impact of the Swaziland birds on the ecology of the species in the broader region. The importance of tag loss or illegibility over time is highlighted. Clearly, any attempt at conserving a species will require a detailed understanding of its population structure, of the sort examined here.