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In semi-arid savannas, abandoned cattle ( Bos taurus) enclosures or kraals have been demonstrated to be nutrient-hotspots for large herbivores. In this study, we examined the interaction between herbivory and forage quality, structure and diversity at 12 kraals (abandoned for 22 years) paired with savanna control plots in Save Valley Conservancy, Zimbabwe. Plant diversity was not different between sites. Herbaceous cover was higher and woody species density lower on abandoned kraals than control plots. Furthermore, abandoned kraals had higher herbaceous productivity and foliar nutrient concentration for grasses than forbs. The abandoned kraals had higher concentration of soil nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), organic carbon (C) compared with control plots and a slightly acidic pH. Grasses were grazed more than forbs on nutrient-rich abandoned kraals. Only herbaceous biomass for grasses had a significant influence on the interaction between plants and herbivory. No clear relationships were observed between forage quality and herbivory and plant species diversity. Abandoned kraals provide patches of nutrient-rich forage, increasing savanna heterogeneity and in turn influence grazing patterns of large herbivores, and therefore influence ecosystem functioning. A conservation monitoring programme is recommended on such nutrient-rich patches as they serve as foraging-hotspots for herbivores in a dystrophic African semi-arid savanna. [ABSTRACT FROM AUTHOR]

The selective nature of trophy hunting may cause changes in desirable phenotypic traits in harvested species. A decline in trophy size of preferred species may reduce hunting destination competitiveness thus compromising the sustainability of trophy hunting as a conservation tool. We explored the trophy quality and trends in harvesting patterns (i.e., 2004–2015) of Cape buffalo (Syncerus caffer), African elephant (Loxodonta africana), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. To analyse the effect of year, area and age on the trophy size, quota size and offtake levels, we used linear mixed models. One sample t-test was used to compare observed trophy size with Safari Club International (SCI) minimum score. Trophy sizes for Cape buffalo and African elephant were below the SCI minimum score. Greater kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015. Age at harvest for Cape buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of African elephant and Greater kudu declined whilst the quota size did not change between 2004 and 2015. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004–2015. The trophy size and harvesting patterns in these species pose a conservation and management dilemma on the sustainability of trophy hunting in this area. We recommend: (1) temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, and (2) introduction of variable trophy fee pricing system based on trophy size. [ABSTRACT FROM AUTHOR]

An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i) surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii) habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii) spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana) for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats. [ABSTRACT FROM AUTHOR]

We investigated the rainfall patterns and associated fluctuations of wild large herbivore species in the Great Limpopo Transfrontier Conservation Area (GLTFCA), southern Africa. The study objectives were to: (i) establish the synchrony in rainfall and drought occurrence patterns in Gonarezhou National Park, Zimbabwe, and four adjacent areas, and (ii) determine the responses of different large herbivore species' populations to droughts. We used annual rainfall data collected from the five sites within the GLTFCA and large herbivore population data collected from multispecies aerial surveys in Gonarezhou and Kruger National Park, South Africa. Our results showed that between 1970 and 2009, Gonarezhou recorded three wet years (1977, 1978 and 2000) and six drought years (1973, 1983, 1989, 1992, 1994 and 2005). However, there were some variations in the drought occurrences between Gonarezhou and the four adjacent areas indicating a weak synchrony in rainfall patterns. Furthermore, seven large herbivore species showed dips in their populations associated with the 1992 severe drought, with most of the species' populations recovering thereafter. Our study suggests that rainfall does have a strong influence on large herbivore population dynamics especially in really dry years in African savanna ecosystems. Our findings underscore the need for further detailed studies on bottom-up processes influencing large herbivore population trends in savanna ecosystems with high rainfall variability. [ABSTRACT FROM AUTHOR]

The study assessed flight behavioural responses of impala (Aepyceros melampus) and kudu (Tragelaphus strepsiceros) to human disturbance and compared densities of common large herbivores across Gonarezhou National Park (non- consumptive land use) and the adjacent Malipati Safari Area (consumptive land use) in southeast Zimbabwe. Animal vigilance was measured by flight behaviour and compared in terms of area and group size. Distance sampling method was used to collect data on densities of large herbivores including namely; impala, kudu, zebra (Equus quagga), giraffe (Giraffa camelopardalis), waterbuck (Kobus ellipsiprytnnus), elephant (Loxodonta africana), warthog (Phacochoerus africanus), steenbok (Raphicerus campestris), common duiker (Sylvicapra grimmia) and nyala (Tragelaphus angasii), and in both study sites. The vigilance of impala and kudu were higher in Malipati than Gonarezhou {p < 0.001). Vigilance in impala was not significantly different with increasing animal group sizes in both Gonarezhou and Malipati (p > 0.05). Densities of common large herbivores were marginally different with Gonarezhou having higher animal densities than Malipati (p < 0.05). Our results suggest that hunting is important in triggering increased vigilance behaviour of herbivores as well as influencing animal densities. Thus, it is important to monitor and reduce negative human activities on animal populations in the study area for enhancing tourism activities and conservation. [ABSTRACT FROM AUTHOR]

Understanding factors influencing large herbivore densities and distribution in terrestrial ecosystems is a fundamental goal of ecology. This study examined environmental factors influencing the density and distribution of wild large herbivores in Gonarezhou National Park, Zimbabwe. Vegetation and surface water were predicted to have a stronger influence than anthropogenic-related disturbances (livestock grazing, fires, settlements and poaching) on the density and distribution of wild large herbivores. Aerial survey data for seven common wild large herbivores conducted in 2007 and 2009 and environmental data were collected. Only grass cover explained a significant proportion of the variation in large herbivore densities and distribution. Moreover, only two species densities significantly differed across the Gonarezhou, namely impala and zebra. In contrast, buffalo, elephant, giraffe, kudu and nyala densities did not differ significantly across the Gonarezhou. Overall, the findings only partly support the study prediction. The study results suggest the need to further investigate the roles of environmental factors at smaller scales in order to tease out their relative strengths in influencing density and distribution of large herbivores. [ABSTRACT FROM AUTHOR]

Post-release monitoring of wildlife is essential to the success of ecological restoration initiatives. Translocation of wildlife to new ecosystems is associated with changes in diet profiles of individuals and ultimately animal performance, since productivity of rangelands varies in time and space. The population decline and local extinction of buffalo and other species in Umfurudzi Park, Zimbabwe, in the late 1980s led to temporary suspension of hunting activities. Recently, efforts have been made to resuscitate Umfurudzi Park through wildlife reintroductions and active ecosystem management. We assessed the diet profile and diet quality of the African buffalo (Syncerus caffer) between 2011 and 2012. A total of 42 grass species constituted the diet spectrum of buffalo. Heteropogon contortus, Eragrostis racemosa, Steroechlaena tenuifolia andThemeda triandra contributed significantly to the buffalo diet during the four seasons of the study period. Although a wide spectrum of grass species was selected in the wet season, the diversity of grass species selected was not significantly different among the seasons. Grass species crude protein deteriorated from 4.5% in the wet season to 3.5% in the dry season. Crude protein and phosphorus levels in buffalo faecal samples were within the recommended nutrient scale for southern Africa large herbivores. We conclude that feed availability and quality may not be limiting the persistence of the reintroduced buffalo. There is a need to closely monitor grass availability, dietary shifts, and forage quality over time, as well as resource partitioning with other feeding guilds. [ABSTRACT FROM AUTHOR]

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Abstract Soil dwelling beetles contribute greatly to biodiversity and offer important services in agroecosystems including predation, weed herbivory and decomposition. An experiment was conducted in the 2013/2014 and 2014/2015 cropping seasons at Chinhoyi University of Technology experiment station, Zimbabwe, to investigate the impact of tillage system (conservation tillage and conventional tillage), fertilizer application rate and weeding intensity on beetle communities in maize. The experiment was laid out in a split-split plot using a randomized complete block design and replicated three times. Beetles were sampled using un-baited pitfall traps. A total of 6020 beetles were collected comprising 53 species, nine families and four functional groups. Tillage system had the strongest effects on beetle diversity. Advanced constrained analysis using principal response curves revealed that the abundances of Anchophthalmus oncotipes decreased under conservation tillage. In contrast, abundances of Zophosis boei , Gonocephalum simplex , Renatiella reticulata and Stenethmus tentyriniformis increased under conservation tillage relative to conventiona tillage (CT). Detritivore abundances were 50.8% and 45% greater under rip line seeding than CT during the hot dry season of 2014 and cold dry season of 2015, respectively. Predator abundances were almost double in basin planting relative to CT during the cold dry season of 2014 and hot humid season of 2015. In the 2014/2015 cropping season, maize grain yield significantly increased (P < 0.05) from 4963 kg ha−1 in CT to 7848 kg ha−1 in basin planting tillage. Application of a high rate of fertilizer increased maize grain yield by 31.2% compared to the low and medium fertilizer application rates. Weeding twice resulted in the highest maize grain yield but there was no yield benefit in increasing weeding intensity more than twice per season. Our results suggest that there is potential for increasing density and diversity of beneficial beetle species through conservation tillage with crop residue retention. [ABSTRACT FROM AUTHOR]