Scielo RSS <![CDATA[Koedoe]]> vol. 59 num. 2 lang. en <![CDATA[SciELO Logo]]> <![CDATA[<b>Seasonal habitat selection by African buffalo <i>Syncerus caffer</i> in the Savuti-Mababe-Linyanti ecosystem of northern Botswana</b>]]> This study aimed to establish seasonal movement and habitat selection patterns of African buffalo Syncerus caffer in relation to a detailed habitat map and according to seasonal changes in forage quality and quantity in the Savuti-Mababe-Linyanti ecosystem (Botswana). Two buffalo were collared in November 2011 and another in October 2012. All three buffalo had greater activities in the mopane-sandveld woodland mosaic during the wet season, which provided high-quality leafy grasses and ephemeral water for drinking, but moved to permanent water and reliable forage of various wetlands (swamps and floodplains) and riverine woodlands during the dry season. Wetlands had higher grass greenness, height and biomass than woodlands during the dry season. Buffalo had similar wet season concentration areas in the 2011-2012 and 2012-2013 wet seasons and similar dry season concentration areas over the 2012 and 2013 dry seasons. However, their dry season location of collaring in 2011 differed dramatically from their 2012 and 2013 dry season concentration areas, possibly because of the exceptionally high flood levels in 2011, which reduced accessibility to their usual dry season concentration areas. The study demonstrates that extremely large and heterogeneous landscapes are needed to conserve buffalo in sandy, dystrophic ecosystems with variable rainfall. CONSERVATION IMPLICATIONS: This study emphasises the importance of large spatial scale available for movement, which enables adaptation to changing conditions between years and seasons. <![CDATA[<b>Conservation implications of brown hyaena (<i>Parahyaena brunnea</i>) population densities and distribution across landscapes in Botswana</b>]]> The brown hyaena (Parahyaena brunnea) is endemic to southern Africa. The largest population of this near-threatened species occurs in Botswana, but limited data were available to assess distribution and density. Our objectives were to use a stratified approach to collate available data and to collect more data to assess brown hyaena distribution and density across land uses in Botswana. We conducted surveys using track counts, camera traps and questionnaires and collated our results and available data to estimate the brown hyaena population based on the stratification of Botswana for large carnivores. Brown hyaenas occur over 533 050 km² (92%) of Botswana. Our density estimates ranged from 0 brown hyaenas/100 km² in strata of northern Botswana to 2.94 (2.16-3.71) brown hyaenas/100 km² in the southern stratum of the Central Kalahari Game Reserve. We made assumptions regarding densities in strata that lacked data, using the best references available. We estimated the brown hyaena population in Botswana as 4642 (3133-5993) animals, with 6.8% of the population in the Northern Conservation Zone, 73.1% in the Southern Conservation Zone, 2.0% in the smaller conservation zones and 18.1% in the agricultural zones. The similar densities of brown hyaenas in the Central Kalahari Game Reserve and the Ghanzi farms highlight the potential of agricultural areas in Botswana to conserve this species. The conservation of brown hyaenas in the agricultural landscape of Botswana is critical for the long-term conservation of the species; these areas provide important links between populations in South Africa, Namibia and Zimbabwe. CONSERVATION IMPLICATIONS: Botswana contains the core of the brown hyaena population in southern Africa, and conflict mitigation on agricultural land is crucial to maintaining connectivity among the range countries. <![CDATA[<b>Farmer-African wild dog (<i>Lycaon pictus</i>) relations in the eastern Kalahari region of Botswana</b>]]> African wild dogs (Lycaon pictus) are the most endangered large carnivores in southern Africa. Direct and indirect persecution by farmers causes significant conservation challenges. Farmer-wild dog conflict in Botswana commonly occurs as a result of cattle and stocked game depredation by wild dogs, affecting farmer livelihood and causing economic and emotional distress. Although wild dogs predate livestock at lower levels than other carnivores, they continue to be killed both indiscriminately and in retaliation for incidents of depredation. Investigating farmer-wild dog conflict is a necessary step towards establishing appropriate conflict mitigation strategies. Eighty livestock and game farmers were interviewed in order to examine farmers' value of, perceptions of and experiences with wild dogs as well as their insights on wild dog impacts and conservation in the eastern Kalahari region of Botswana. Interviews were semi-structured and used open-ended questions to capture complexities surrounding farmer-wild dog relations. This research contributes baseline data on wild dogs in understudied tribal land and commercial livestock and game farms in eastern Kalahari. It confirms the presence of wild dogs, livestock and stocked game depredation by wild dogs and negative perspectives amongst farmers towards wild dogs and their conservation. Mean losses were 0.85 livestock per subsistence farmer, 1.25 livestock per commercial livestock farmer, while game farmers lost 95.88 game animals per farmer during January 2012 through June 2013. Proportionally, more subsistence farmers than commercial livestock farmers and game farmers held negative perspectives of wild dogs (χ² = 9.63, df = 2, p < 0.05). Farmer type, education level, socioeconomic status and land tenure, as well as positive wild dog characteristics should be considered when planning and operationalising conflict mitigation strategies. As such, conservation approaches should focus on conservation education schemes, improved wild prey base for wild dogs, poverty alleviation, and community engagement in order to offer long-term opportunities for addressing farmer-wild dog conflict in Botswana. CONSERVATION IMPLICATIONS: Our research contributes to wild dog conservation in Botswana by confirming the presence of wild dogs and the occurrence of livestock and stocked game depredation in previously understudied tribal land and commercial livestock and game farms in eastern Kalahari. To improve predominately negative perceptions of wild dogs and reduce conflict, practitioners should focus their efforts on conservation education schemes, improved wild prey base for wild dogs, poverty alleviation, and community engagement. <![CDATA[<b>Spatial refuges buffer landscapes against homogenisation and degradation by large herbivore populations and facilitate vegetation heterogeneity</b>]]> Environmental heterogeneity across savanna landscapes, including different seasonal resources at different distances to water, may play a critical role in maintaining the size and diversity of wildlife populations and the sustainability of their resource base. We investigated whether extensive landscapes with functionally diverse seasonal resources and large waterless regions can mediate the effect of herbivory on plant composition, structure and diversity. Vegetation composition, structure and richness in two different vegetation types (mopane and sandveld woodland) at three distance zones (0 km - 5 km, 10 km - 15 km and > 20 km) from the permanent water of the Okavango Delta and Linyanti Swamps were surveyed. We modelled vegetation response of the most abundant species to herbivory in relation to distance from permanent water, and included fire frequency as a covariate. Trees favoured by elephants during the dry season occurred typically as immature, pollarded populations within 5 km of permanent water sources while mature tall populations of these species were found far from water (> 10 km - 15 km). Similarly, short high-quality grazing grasses were higher in abundance within 5 km of permanent water, whereas taller high-quality perennial grasses peaked in abundance beyond 20 km from permanent water. Trends in herbaceous richness with distance from water were contingent upon vegetation type, while tree richness did not change with distance from water. Spatial refuges in waterless regions of landscapes facilitate the creation of heterogeneity of vegetation structure, composition and richness by large herds of mammalian herbivores. Therefore, the extension of herbivore dry season foraging range, for example, by the creation of artificial water points (AWP) in backcountry woodlands, could seriously undermine the resilience of landscapes to herbivory by reducing the availability of spatial refuges. Consequently, it reduces the resilience of herbivore and predator populations that depend on these spatial refuges. We strongly advise that future scientific work, and management and policy actions should be focused on the identification and sustaining of these spatial refuges in wildlife areas. CONSERVATION IMPLICATIONS: Management and policy actions should be focused on the identification and sustainability of spatial refuges in wildlife areas. Too many AWP in backcountry woodlands could undermine the resilience of landscapes to herbivory by reducing the proportion of landscapes beyond 15 km from permanent water. <![CDATA[<b>The vegetation and wildlife habitats of the Savuti-Mababe-Linyanti ecosystem, northern Botswana</b>]]> This study classified the vegetation of the Savuti-Mababe-Linyanti ecosystem (SMLE), northern Botswana and developed a detailed map that provides a reliable habitat template of the SMLE for future wildlife habitat use studies. The major vegetation units of the SMLE were determined from satellite imagery and field visits and then mapped using Landsat 8 and RapidEye imagery and maximum likelihood classifier. These units were sampled using 40 m x 20 m (800 m²) plots in which the coverage of all plant species was estimated. Non-metric multidimensional scaling (NMS) demonstrated that plant communities were determined by gradients in soil texture or fertility and wetness. NMS 1 represented a gradient of soil texture with seven woodland communities on sandy soils (sandveld communities and Baikiaea forest) dominated by Baikiaea plurijuga in Baikiaea forest and Terminalia sericea and Philenoptera nelsii in sandveld, with various indicator species differentiating the various sandveld community types. Mopane woodland further from and riparian woodland adjacent to permanent water was common on less sandy alluvial soils. Mineral-rich, heavy clay soils in the sump of a large paleolake system support open grassland and mixed Senegalia/Vachellia (Acacia) savanna, with the mineral-rich soils supporting grasses high in minerals such as phosphorus, calcium, sodium and potassium, and thus this region is a critical wet season range for migratory zebra. Taller, high-quality grasses in the mosaic of sandveld and mopane woodland communities provide critical grazing for taller grass grazers such as buffalo, roan and sable antelope, whereas wetland communities provide reliable green forage during the dry season for a variety of herbivores, including elephant. This study has demonstrated how large-scale environmental gradients determine functional habitat heterogeneity for wildlife. CONSERVATION IMPLICATIONS: Our study demonstrated that the functionality of protected areas is determined by large-scale environmental gradients. Thus conservation science must aim to ensure that protected areas cover the full range of key environmental gradients in a region (soil texture and wetness in our study). Our habitat map provides a data base for wildlife habitat use studies in the region. <![CDATA[<b>Ground survey of red lechwe in the Linyanti swamps and Chobe floodplains, northern Botswana</b>]]> A ground survey of red lechwe was carried out in the Linyanti swamps and the Chobe floodplains of northern Botswana in the dry and wet seasons of 2012 and 2013, respectively. We documented numbers, sex ratio and age structure of red lechwe within the linear strips of 25 km × 300 m along the Linyanti swamps and the Chobe floodplains. Results indicated a significant difference in the numbers of red lechwe between sites and seasons. About 66 and 755 red lechwe were estimated for Chobe in the dry and wet season, respectively, with 343 and 261 of them estimated for Linyanti in the dry and wet season, respectively. In Chobe, the red lechwe densities varied widely between seasons (9 red lechwe/km² - 101 red lechwe/km²) compared with Linyanti, where the densities did not vary much between seasons (35 red lechwe/km² - 46 red lechwe/km²). The lower densities of red lechwe in Chobe in the dry season when compared with the wet season suggest a possible seasonal shift in the distribution of red lechwe to the nearby Zambezi floodplains in Namibia. CONSERVATION IMPLICATIONS: The higher number of red lechwe in the Chobe floodplains in the wet season indicates the potential of the floodplains as a habitat for this species in that season. The dry season shift in the distribution of red lechwe in Chobe presents an opportunity for local communities in Namibia to engage in tourism, whereas the return of the red lechwe to the floodplains in the wet season ensures protection of the animals as well as boosts the tourism potential of the Chobe National Park.