Acknowledgements to reviewers

No abstract available.

The first sub-meter resolution digital elevation model of the Kruger National Park, South Africa

The use of digital elevation models has proven to be crucial in numerous studies related to savanna ecosystem research. However, the insufficient spatial resolution of the chosen input data is often considered to be a limiting factor when conducting local to regional scale ecosystem analysis. The elevation models and orthorectified imagery created in this study represent the first wall-to-wall digital elevation data sets produced for the Kruger National Park (KNP), South Africa, at very high spatial resolution. Using colour-infrared (CIR) aerial imagery from the archives of the Chief Directorate: National Geo-spatial Information (CDNGI), Department of Agriculture, Land Reform and Rural Development (DALRRD) aerial acquisition programme, we created digital surface models (DSMs), digital terrain models (DTMs) and CIR orthomosaics covering the entire KNP with a nominal ground sampling distance of 0.25 m. Elevation information was derived using state-of-the-art stereo matching algorithms that utilised semi-global matching (SGM) as a cost aggregation function throughout the image pairing, using the Enterprise software from CATALYST. The final products were validated against reference products, and showed excellent agreement with R² values of 0.99. Further, the validation of the DTM and DSM revealed median absolute vertical height error (LE90) across all sites of 1.02 m and 2.58 m, respectively. The orthomosaics were validated with in situ ground control points (GCPs) exhibiting a horizontal Circular Probable Error (CPE) of 1.37 m. The data resulting from this work will be distributed freely with the aim of fostering more scientific studies in the African science community and beyond.Conservation implications: Accurate information about terrain and surface height are crucial inputs to a variety of scientific analysis, which are essential in protected areas, such as flood prediction or fire hazard estimation. Elevation data sets and orthomosaics in very high resolution can therefore serve as a crucial tool to improve park management and foster positive implications on conservation efforts.

Erratum: Elephant population responses to increased density in Kruger National Park

No abstract available.

A reclassification and description of the Waterberg Mountain vegetation of the Marakele National Park, Limpopo province, South Africa

The description and classification of vegetation are important for conservation and resource management. The aim of this study was to identify, reclassify and describe the plant communities present in the Waterberg Mountain vegetation of the Marakele National Park in the Limpopo province, South Africa. A phytosociological classification, mapping and description of sections of the Waterberg Mountain vegetation in the park were done in 1995. Since 1995, various farms adjacent to the park have been bought and incorporated into it. Little is known about the vegetation and habitat status of these newly acquired areas, which led to this study. The floristic data were analysed according to the Braun-Blanquet procedure using the Braun Blanquet Personal Computer (BBPC) suite as well as the JUICE software package, whilst the diversity of the plant communities was determined using the Shannon–Wiener and Gini–Simpson indices. A total of 12 plant communities were identified and are described according to their diagnostic, constant and dominant plant species as determined from the synoptic table analysis as well as their characteristic species as derived from the phytosociological table. Based on the topography and plant species composition, the vegetation can be grouped into five major groups, namely the: (1) lower midslope and plateau shrub- and woodlands, (2) high altitude midslope woodland, (3) high-lying plateau and midslope grass-, shrub- and woodlands, (4) ravine, footslope and drainage line forests and woodland, and (5) higher-lying plateau wetlands and forblands. The high altitude midslope grassland and shrubland and the lower midslope and plateau areas have the highest diversity. The high-lying vegetation has affinity with Bankenveld and Drakensberg vegetation, whilst the relatively low-lying plateaus and midslope vegetation are typical of the bushveld areas.Conservation implications: This reclassification, mapping and description of the Waterberg Mountain vegetation have been incorporated into the Management Plan for the park. It will enable managers to make scientifically based decisions on the management of the different ecosystems to ensure biodiversity conservation. This vegetation study also provides baseline information that allows for vegetation assessments to determine veld condition, carrying capacity and stocking density for the park.

Distribution and diversity of entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) in a South African nature reserve

Entomopathogenic nematodes (EPNs) are microscopic roundworms that are found in soil worldwide. They deliver an important ecosystem service through preventing natural flares in insect reproduction by means of utilising the soil stages of insects as a food source and by acting as natural biocontrol agents. A survey of EPNs was conducted in the JS Marais Nature Reserve, Stellenbosch, in the Western Cape province of South Africa. Soil samples were baited with the larvae of three susceptible hosts, codling moth (Cydia pomonella), wax moth (Galleria mellonella) and mealworm (Tenebrio molitor) to determine the presence of EPN. Of the 76 soil samples collected across the reserve, 39 were found to be positive for the presence of EPN (51.32%). Among the positive samples, 87% contained Steinernema isolates, 8% contained Heterorhabditis and 5% contained the Oscheius sp. Morphological and molecular studies were performed to characterise the isolates to species level. The Steinernema species were identified as Steinernema khoisanae in 34 samples, and as Steinernema nguyeni in five samples. The only species of Heterorhabditis found was H. safricana, which was identified from three samples. An unknown Oscheius sp. was found in two samples. The reserve’s population of S. khoisanae showed interesting inter-individual variation (93%) early in the internal transcribe spacer (ITS) region, leading to short single-usable sequences, which, in most cases, included only the ITS1 or ITS2 region. However, using the D2D3 confirmed their identity as S. khoisanae, with such occurring in all areas and soil types of the reserve.Conservation implications: The undisturbed alluvial fynbos and renosterveld of the JS Marais Nature Reserve showed high EPN abundance and diversity in stark contrast to the agro-ecosystems present in the Cape floristic region. This finding, on a micro level, should be conserved for future bioprospecting in the fynbos for EPNs with potential as biocontrol agents.

The spatial distribution of the woodland communities and their associated environmental drivers in the Golden Gate Highlands National Park, South Africa

The extreme variability in the topography, altitude and climatic conditions in the temperate Grassland Mountains of Southern Africa is associated with the complex mosaic of grassland communities with pockets of woodland patches. Understanding the relationships between plant communities and environmental parameters is essential in biodiversity conservation, especially for current and future climate change predictions. This article focused on the spatial distribution of woodland communities and their associated environmental drivers in the Golden Gate Highlands (GGHNP) National Park in South Africa. A generalized linear model (GLM) assuming a binomial distribution, was used to determine the optimal environmental variables influencing the spatial distribution of the woodland communities. The Coefficient of Variation (CV) was relatively higher for the topographic ruggedness index (68.78%), topographic roughness index (68.03), aspect (60.04%), coarse fragments (37.46%) and the topographic wetness index (31.33) whereas soil pH, bulk density, sandy and clay contents had relatively less variation (2.39%, 3.23%, 7.56% and 8.46% respectively). In determining the optimal number of environmental variables influencing the spatial distribution of woodland communities, roughness index, topographic wetness index, soil coarse fragments, soil organic carbon, soil cation exchange capacity and remote-sensing based vegetation condition index were significant (p 0.05) and positively correlated with the woodland communities. Soil nitrogen, clay content, soil pH, fire and elevation were also significant but negatively correlated with the woodland communities. The area under the curve (AUC) of the receiver operating characteristics (ROC) was 0.81. This was indicative of a Parsimonious Model with explanatory predictive power for determination of optimal environmental variables in vegetation ecology.Conservation implications: The isolated woodland communities are sources of floristic diversity and important biogeographical links between larger forest areas in the wider Drakensberg region. They provide suitable habitats for a larger number of forest species and harbour some of the endemic tree species of South Africa. They also provide watershed protection and other important ecosystem services. Understanding the drivers influencing the spatial distribution and persistence of these woodland communities is therefore key to conservation planning in the area.

Is climate change a concern for the ownership of game within fenced wildlife areas?

No abstract available.

Mammals in the mountains: An historical review and updated checklist of the mammals of the Mountain Zebra National Park

Based on published and unpublished records, together with original data collected from regular field trips over a 15-year period, 68 mammal species have been reliably recorded from the Mountain Zebra National Park. I assessed the current status of all mammal species, in relation to park expansion and research effort over time (1937–2020). Although numerous large and charismatic mammal species have been reintroduced to the park since it was gazetted in 1937, both in an attempt to restore the historical diversity of the region and to attract tourists, research effort in the surveying of the smaller and more cryptic mammal species has been sorely lacking. I recommend that future survey work targets the small, mostly fossorial mammals (i.e. golden and rodent moles, elephant shrews and gerbils) and insectivorous bats.Conservation implications: This work provides critical presence data for several mammal species from an important protected area that straddles three biomes in South Africa.