The small size of many African protected areas makes adjacent rangelands potentially important in the local survival of wild animals. In order to assess the importance of pastoral areas to wild ungulates, we studied density and habitat choice of wild ungulates and cattle in Lake Mburo National Park, Uganda, the adjacent exclusively pastoral Nshara Dairy Ranch and on private land consisting of a mixture of ranching and subsistence farms. Transects, in the three land-use zones, were walked during the wet season and the data were analysed by DISTANCE sampling technique. We found significantly higher total density of wild ungulates on the dairy ranch compared with the National Park and private land. There was no significant difference in total wild animal density between the National Park and private land. Impala (Aepyceros melampus), zebra (Equus quagga), bushbuck (Tragelaphus scriptus) and waterbuck (Kobus ellipsiprymnus) had significantly higher densities on the dairy ranch compared to the National Park. Only eland (Taurotragus oryx) density was higher in the National Park compared to private land. Wild ungulates and cattle showed a high degree of habitat overlap, generally preferring open grassland. Our study shows that high densities of wild ungulates are not necessarily associated with protected areas. Pastoral areas may be important for populations of wild herbivores during the growing season despite a pronounced presence of livestock.

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Vast areas of the African savanna landscapes are characterized by tree‐covered Macrotermes termite mounds embedded within a relatively open savanna matrix. In concert with termites, large herbivores are important determinants of savanna woody vegetation cover. The relative cover of woody species has considerable effects on savanna function. Despite the potentially important ecological relationships between termite mounds, woody plants, large herbivores, and birds, these associations have previously received surprisingly little attention. We experimentally studied the effects of termites and large herbivores on the avian community in Lake Mburo National Park, Uganda, where woody vegetation is essentially limited to termite mounds. Our experiment comprised of four treatments in nine replicates; unfenced termite mounds, fenced mounds (excluding large mammals), unfenced adjacent savanna, and fenced savanna. We recorded species identity, abundance, and behavior of all birds observed on these plots over a two‐month period, from late dry until wet season. Birds used termite mounds almost exclusively, with only 3.5% of observations occurring in the treeless intermound savanna matrix. Mean abundance and species richness of birds doubled on fenced (large herbivores excluded) compared to unfenced mounds. Feeding behavior increased when large mammals were excluded from mounds, both in absolute number of observed individuals, and relative to other behaviors. This study documents the fundamental positive impact of Macrotermes termites on bird abundance and diversity in an African savanna. Birds play crucial functional roles in savanna ecosystems, for example, by dispersing fruits or regulating herbivorous insect populations. Thus, the role of birds in savanna dynamics depends on the distribution and abundance of termite mounds.

1 The banana weevil Cosmopolites sordidus Germar (Coleoptera: Curculionidae) is a major pest in banana (Musa spp.) growing areas. The weevil is known to be relatively sedentary and closely associated with its host plant but little is known about the species' ability to migrate between banana fields and in nonhost habitats. 2 Mark-recapture experiments were conducted to assess the weevils' migration potential, possible differences between the sexes, and the relative attractiveness of pseudostem and pheromone baits. 3 One thousand two hundred marked weevils were released in the nonhost habitat at five distances (5, 10, 20, 40 and 70 m) from fresh pseudostem, and from pitfall traps baited with 45 mg of sordidin. 4 Two hundred males and 200 females were marked and released at five distances (5, 10, 20, 40 and 70 m) from the pheromone traps. 5 Distance and distance/bait interactions had a significant effect on recaptured weevils (binary logistic regression). The two baits were almost equally attractive to weevils in the range 0-10 m, whereas the pheromone was more attractive in the range 10-100 m. 6 Distance, bait and distance/bait interactions had a significant effect on the time elapsed from release to recapture (regression with life data) but the pattern observed was not consistent. 7 There was no significant difference between males and females with respect to distance or time elapsed from release to recapture. 8 The results obtained in the present study show that the migration potential of the banana weevil is greater than previously reported. This should be taken into account when new banana fields are established with clean planting material.

A farmer participatory research approach to assess the effectiveness of field sanitation and regular trapping on banana weevil populations.Abstract -Introduction. Small-scale banana producers in Tanzania are facing constraints caused by the destructive activities of the banana weevil (Cosmopolites sordidus Germar). Many currently used methods of addressing the problem are ineffective or too expensive for local farmers to implement. Materials and methods. A combination of two integrated pest management (IPM) tools (regular trapping in combination with field sanitation) was tested at two farmer-managed sites (Bujela and Kyimo) and one researcher-managed site (SUA-Morogoro). Treated areas were surrounded by untreated control areas where no trapping and limited sanitation was done. Changes in population densities were estimated by the mark-recapture procedure and the Lincoln index. Results and discussion. After eight months, weevil populations in the cleaned and trapped areas had been reduced by 33% (Bujela), 33% (Kyimo) and 74% (SUA). The change in population sizes in the control areas differed greatly, possibly due to discrepancies in field management between farmers' and researchers' practice. Trap types, areas and sites affected the number of weevils captured. Disc-onstump (DOS) traps captured more weevils than corm disc (CD) and pseudostem (PS) traps. Weevils responded more strongly to traps in the clean area at SUA compared with the other two sites, probably because the more rigid sanitation practices at SUA meant that volatiles from the traps were less likely to be masked by volatiles from surrounding residues. Conclusion. Regular trapping with field sanitation can greatly reduce populations of banana weevils, but strict adherence to method execution is required in order to gain favourable results. Tanzania / Musa / integrated pest control / Cosmopolites sordidus / traps / pseudostems / corms / farmer participation / cultivation / weeding Recherche participative avec les agriculteurs pour évaluer l'efficacité de l'assainissement en champ et du piégeage régulier des populations de charançons du bananier.Résumé -Introduction. En Tanzanie, les petits producteurs de bananes sont confrontés à des contraintes liées aux activités destructrices du charançon du bananier (Cosmopolites sordidus Germar). De nombreuses méthodes actuellement utilisées pour résoudre ce problème sont inefficaces ou trop coûteuses à mettre en oeuvre pour les agriculteurs locaux. Matériel et méthodes. Une combinaison de deux outils de lutte intégrée (IPM) (piégeage régulier combiné avec un assainissement du terrain) a été testée sur deux sites gérés par des agriculteurs (Bujela et Kyimo) et sur un site géré par des chercheurs (SUA-Morogoro). Les zones traitées ont été entourées de zones témoins non traitées où aucun piégeage ou assainissement n'ont été faits. Les variations de densité de la population ont été estimées par marquage-recapture et par utilisation de l'indice de Lincoln. Résultats et discussion. Après huit mois, les populations de ...