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91 results for “African savannas”
Study of catenal separation in the herbaceous layer of South African Savanna subtypes.
This dataset provides a comprehensive inventory of herbaceous plant community composition and absolute density along topographic (catenal) gradients in the South African savanna. Data were collected across three distinct reserves representing diverse ecological zones: Letlapa Pula Game Reserve (LPGR; Central Bushveld bioregion), Selati Game Reserve (SGR; Mopane bioregion), and Kempiana Nature Reserve (KNR; Lowveld bioregion). The study utilized a nested hierarchical sampling design to quantify the distribution of grasses and forbs across three primary terrain units: Crest, Midslope, and Footslope. In each reserve, 90 plots of 2 x 2 m were surveyed (30 plots per terrain unit, nested within 40 x 40 m quadrats), resulting in a total of 270 sampling units. The dataset includes counts of individual plants per species (108 species in LPGR, 93 species in SGR, and 74 species in KNR). The dataset is organized into three CSV files, one for each study area, containing: 1. Bioregion and Site Identifiers: Locating the data within the South African National Biodiversity Institute (SANBI) framework. 2. Topographic Context: Classification by catenal position (Crest, Midslope, Footslope). 3. Species Abundance Matrix: Absolute density counts of all identified herbaceous species. This data is intended to support research into catenal separation, environmental filtering, beta diversity, and the functional role of the herbaceous layer in savanna ecosystem resilience. It provides a baseline for understanding how local topography and regional climatic factors interact to shape plant community structure.
African Savanna grasses outperform trees across the full spectrum of soil moisture availability
<p>Summary</p> <ul> <li>Models of tree-grass coexistence in savannas make different assumptions about the relative performance of trees and grasses under wet vs. dry conditions. We quantified transpiration and drought tolerance traits in 26 tree and 19 grass species from the African savanna biome across a gradient of soil water potentials to test for a tradeoff between water use under wet conditions and drought tolerance.</li> <li>We measured whole-plant hourly transpiration in a growth chamber and quantified drought tolerance using leaf osmotic potential (Ψ<sub>osm</sub>). We also quantified whole-plant water use efficiency (WUE) and relative growth rate (RGR) under well-watered conditions.</li> <li>Grasses transpired twice as much as trees on a leaf-mass basis across all soil water potentials. Grasses also had a lower Ψ<sub>osm</sub> than trees, indicating higher drought tolerance in the former. Higher grass transpiration and WUE combined to largely explain the threefold RGR advantage in grasses.</li> <li>Our results suggest that grasses outperform trees under a wide range of conditions, and that there is no evidence for a trade-off in water use patterns in wet vs. dry soils. This work will help inform mechanistic models of water use in savanna ecosystems, providing much-needed whole-plant parameter estimates for African species.</li> </ul>
Data from: Grazing herbivores reduce herbaceous biomass and fire activity across African savannas
<p>Fire and herbivory interact to alter ecosystems and carbon cycling. In savannas, herbivores can reduce fire activity by removing grass biomass, but the size of these effects and what regulates them remain uncertain. To examine grazing effects on fuels and fire regimes across African savannas, we combined data from herbivore exclosure experiments with remotely sensed data on fire activity and herbivore density. We show that, broadly across African savannas, grazing herbivores substantially reduce both herbaceous biomass and fire activity. The size of these effects was strongly associated with grazing herbivore densities and, surprisingly, was mostly consistent across different environments. A one-zebra increase in herbivore biomass density (~100 kg/km<sup>2</sup> of metabolic biomass) resulted in a ~53 kg/ha reduction in standing herbaceous biomass and a ~0.43 percentage point reduction in burned area. Our results indicate that fire models can be improved by incorporating grazing effects on grass biomass.</p>
Data from: Vegetation management shapes arthropod and bird communities in an African savanna
<p>Habitat heterogeneity is a key driver of the diversity and distribution of species. African savannas are experiencing changes to their vegetation structure causing shifts towards increased woody plant cover, which results in vegetation structure homogenization. Given the impact that increasing woody plant cover has on patterns of animal use, resource managers across Africa are implementing habitat management practices that are intended to reduce woody plant cover. To understand the ecological implications of various habitat management practices on arthropod and bird communities, we leveraged large-scale tree clearing and subsequent mowing in an African savanna to understand how changes to both the herbaceous layer and woody plant cover (i.e., structural heterogeneity) may shape arthropod and bird communities at the local scale. We focused on four replicated treatments: 1) annual summer mow, 2) annual winter mow, 3) >5 years since last mow (rest), and 4) an adjacent unmanipulated savanna to act as a control. We found that the mowing treatments significantly influenced vegetation structure both with respect to tree density and herbaceous layer. Both arthropod and bird community composition varied across treatments. Grass biomass was the best predictor of arthropod richness and abundance, with arthropods selecting for areas with high biomass. Insectivorous bird richness and abundance was driven by tree density (i.e., perching locations) and not arthropod abundance. Our results suggest that vegetation management practices contribute to habitat heterogeneity at the landscape scale and increase bird species richness through species turnover. However, we caution that if a single vegetation management practice dominates the landscape, it is plausible that it could lead to the simplification of the avian community.</p>
Data from: N₂-fixation is linked to the ability to encroach in African savanna trees
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Data from: Grazing herbivores reduce herbaceous biomass and fire activity across African savannas
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Elephant megacarcasses increase local nutrient pools in African savanna soils and plants
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Insect herbivory in a South African savanna-forest mosaic: neglected but substantial
<p>These are primary data for the study of insect herbivory conducted in the savanna-forest mosaic of HluHluwe Imfolozi Park in South Africa. The submission contains the following files: specifically, notes for scripts and data particularly used in this study.</p> <p>1. Script 00_Configuration for R<br>2. Script 01_types_of_herbivory represents Figure 3a and Figure S1<br>3. Script 02_subset7_speciesALLhabitats represents Figure 3b, Figure S4, S5<br>4. Script 03_leaf_size_explorations represents Figures S2 and S3<br>5. Script 04_Species_traits_analyses represents Table 1<br>6. Script 05_Savanna correlation<br>7. Script 06_herbivory_savanna_PCA represent figure 4b</p> <p>Data used:<br>1. Data = Distribution_herbivory_class represented Figure_2b & TableS4<br>2. Data = Mean proportion of leaf area eaten by chewers and miners per individual plant species represent figure 2a<br>3. Data = Data_Table S1_fire_mammal gradient<br>4. Data = Leaf sizes investigations for all plant species<br>5. Data = KTraits_20220625_PhylTrait.csv represents phylogenetic correlation signals in table 1 for correlation matrix (Pearson correlation).<br>6. Data = 07_dataset_herbivory_fortraits.csv represents correlation table 1 or correlation matrix (Pearson correlation).<br>7. Data = Environment_savanna_correlations_ExcelPlot.2024 represents Figure S6a & 6b</p>
Ecological consequences of large herbivore exclusion in an African savanna: 12 years of data from the UHURU experiment
<p>Diverse communities of large mammalian herbivores (LMH), once widespread, are now rare. LMH exert strong direct and indirect effects on community structure and ecosystem functions, and measuring these effects is important for testing ecological theory and for understanding past, current, and future environmental change. This in turn requires long-term experimental manipulations, owing to the slow and often nonlinear responses of populations and assemblages to LMH removal. Moreover, the effects of particular species or body-size classes within diverse LMH guilds are difficult to pinpoint, and the magnitude and even direction of these effects often depends on environmental context. Since 2008, we have maintained the Ungulate Herbivory Under Rainfall Uncertainty (UHURU) experiment, a series of size-selective LMH exclosures replicated across a rainfall/productivity gradient in a semi-arid Kenyan savanna. The goals of the UHURU experiment are to measure the effects of removing successively smaller size classes of LMH (mimicking the process of size-biased extirpation) and to establish how these effects are shaped by spatial and temporal variation in rainfall. The UHURU experiment comprises three LMH-exclusion treatments and an unfenced control, applied to 9 randomized blocks of contiguous 1-ha plots (n = 36). The fenced treatments are: "MEGA" (exclusion of megaherbivores, elephant and giraffe); "MESO" (exclusion of herbivores ≥40 kg); and "TOTAL" (exclusion of herbivores ≥5 kg). Each block is replicated three times at three sites across the 20-km rainfall gradient, which has fluctuated over the course of the experiment. The first five years of data were published previously (Ecological Archives E095-064) and have been used in numerous studies. Since that publication, we have (a) continued to collect data following the original protocols, (b) improved the taxonomic resolution and accuracy of plant and small-mammal identifications, and (c) begun collecting several new data sets. Here, we present updated and extended raw data from the first 12 years of the UHURU experiment (2008–2019). Data include daily rainfall data throughout the experiment; annual surveys of understory plant communities; annual censuses of woody-plant communities; annual measurements of individually tagged woody plants; monthly monitoring of flowering and fruiting phenology; every-other-month small-mammal mark-recapture data; and quarterly large-mammal dung surveys.</p>
Fire, grazers and browsers interact with grass competition to determine tree establishment in an African savanna
<p>In savanna ecosystems, fire and herbivory alter the competitive relationship between trees and grasses. Mechanistically, grazing herbivores favor trees by removing grass, which reduces tree-grass competition and limits fire. Conversely, browsing herbivores consume trees and limit their recovery from fire. Herbivore feeding decisions are in turn shaped by risk-resource trade-offs that potentially determine the spatial patterns of herbivory. Identifying the dominant mechanistic pathways by which fire and herbivores control tree cover remains challenging, but is essential for understanding savanna dynamics. We used an experiment in the Serengeti ecosystem and a simple simulation driven by experimental results to address two main aims: (1) determine the importance of direct and indirect effects of grass, fire and herbivory on seedling establishment; and (2) establish whether predators determine the spatial pattern of successful seedling establishment via effects on mesoherbivore distribution. We transplanted tree seedlings into plots with a factorial combination of grass and herbivores (present/absent) across a lion kill-risk gradient in the Serengeti, burning half of the plots near the end of the experiment. Ungrazed grass limited tree seedling survival directly via competition, indirectly via fire, and by slowing seedling growth, which drove higher seedling mortality during fires. These effects restricted seedling establishment to below 18% and, in conjunction with browsing, resulted in seedling establishment dropping below 5%. In the absence of browsing and fire, grazing drove a 7.5-fold increase in seedling establishment. Lion predation risk had no observable impact on herbivore effects on seedling establishment. The severe negative effects of grass on seedling mortality suggests that regional patterns of tree cover and fire may overestimate the role of fire in limiting tree cover, with regular fires representing a proxy for the competitive effects of grass.</p>
Data: Drought and fire determine juvenile and adult woody diversity and dominance in a semi-arid African savanna
<p><em>Aim</em>: To understand how communities of adult and juvenile (seedlings and saplings) woody plants were impacted by fire and the 2014 – 2016 El Niño drought in Kruger National Park, South Africa.</p> <p><em>Methods</em>: We used a landscape scale fire experiment spanning 2013-2019 in a semi-arid savanna in the central west of Kruger National Park (mean annual precipitation, 543 mm). Adult and juvenile woody species composition were recorded during and after the drought in 40 plots that experienced a mix of no fire, moderate fire and frequent fire treatments. Using multivariate modelling, we related community composition in juvenile and adult woody plants to year of sampling and the experimental fire treatments.</p> <p><em>Results</em>: Post-drought, there was significant adult woody plant top-kill, especially in dominant species <em>Dichrostachys cinerea</em> (81% reduction in abundance), <em>Acacia nigrescens</em> (30%), and <em>Combretum apiculatum</em> (19%), but no significant change in adult species richness. Two years post-drought, abundance of all juveniles decreased by 35%, and species richness increased in juveniles in both the frequent fire (7%) and no fire treatments (32%).</p> <p><em>Conclusion</em>: Counter-intuitively, the El Niño drought increased species richness of the woody plant community due to the recruitment of new species as juveniles, a potential lasting impact on diversity, and where different fire regimes were associated with differences in community composition. Drought events in semi-arid savannas could drive temporal dynamics in species richness and composition in previously unrecognised ways.</p>
Data from: Integrating herbivore assemblages and woody plant cover in an African savanna to reveal how herbivores respond to ecosystem management
<p>African savannas are experiencing anthropogenically-induced stressors that are accelerating the increase of woody vegetation cover. To combat this, land managers frequently implement large-scale clearing of trees, which can have a cascading influence on mammalian herbivores. Studies rarely focus on how differences in woody cover influence the herbivore assemblage, making it difficult to assess how aggressive measures, or the lack of management, to counteract increasing woody cover affect the local composition and biodiversity of herbivores. We address this knowledge gap by applying a model-based clustering approach to field observations from to identify multiple herbivore–vegetation ‘configurations,’ defined as unique sets of herbivore assemblages (i.e., groups of herbivores) associated with differing woody plant covers. Our approach delineated how tree-clearing influences the distribution and abundance of the herbivore community in relation to surrounding savanna areas, which represent a natural mosaic of varying woody cover. Regardless of season, both intensively managed areas cleared of trees and unmanaged areas with high tree cover contained configurations that had depauperate assemblages of herbivores (low species richness, low abundance). By contrast, habitats with intermediate cover of woody vegetation had much higher richness and abundance. These results have substantial implications for managing African savannas in a rapidly changing climate.</p>
Wild herbivores enhance resistance to invasion by exotic cacti in an African savanna
<p>1. Whether wild herbivores confer biotic resistance to invasion by exotic plants remains a key question in ecology. There is evidence that wild herbivores can impede invasion by exotic plants, but it is unclear whether and how this generalises across ecosystems with varying wild herbivore diversity and functional groups of plants, particularly over long-term (decadal) time frames.</p> <p>2. Using data from three long-term (13- to 26-year) exclosure experiments in central Kenya, we tested the effects of wild herbivores on the density of exotic invasive cacti, <em>Opuntia stricta</em> and <em>O. ficus-indica</em> (collectively, <em>Opuntia</em>), which are among the worst invasive species globally. We also examined relationships between wild herbivore richness and elephant occurrence probability with the probability of <em>O. stricta</em> presence at the landscape level (6,150 km<sup>2</sup>).</p> <p>3. <em>Opuntia</em> densities were 74% to 99% lower in almost all plots accessible to wild herbivores and increased more rapidly in plots excluding wild herbivores. These effects were largely driven by megaherbivores (≥1,000 kg), particularly elephants.</p> <p>4. At the landscape level, modelled <em>Opuntia</em> occurrence probability was negatively correlated with estimated species richness of wild herbivores and elephant occurrence probability. On average, O. stricta occurrence probability fell from ~0.56 to ~0.45 as wild herbivore richness increased from 6 to 10 species and fell from ~0.57 to ~0.40 as elephant occurrence probability increased from ~0.41 to ~0.84. These multi-scale results suggest that any facilitative effects of <em>Opuntia</em> by wild herbivores (e.g., seed/vegetative dispersal) are overridden by suppression (e.g., consumption, uprooting, trampling).</p> <p>5. <em>Synthesis</em>. Our experimental and observational findings that wild herbivores confer resistance to invasion by exotic cacti add to evidence that conserving and restoring native herbivore assemblages (particularly megaherbivores) can increase community resistance to plant invasions.</p>
Ecosystem-wide responses to fire and large mammal herbivores in an African savanna
<p>Fire and large mammal herbivores (LMH) are the principal top-down forces maintaining savanna structure. Nonetheless, experiments designed to investigate interactions between fire and LMH are rare in savannas, and relationships between environmental variation and biodiversity in the context of fire and LMH are poorly understood. This study addresses these gaps by manipulating the presence of LMH and early and late dry season fires in a tropical African savanna. In addition, this work simultaneously explores environmental variables including soil and foliar quality, vegetation cover, and nearby water sources to more holistically describe factors affecting savanna functioning and biodiversity. </p> <p>After one year of experimental treatments, changes in vegetation were already apparent. Shrub abundance and richness and grass richness were higher in the absence of LMH, while grass biomass increased three-fold in burned plots as compared to unburned plots. Foliar nutrients tended to increase in open plots, while phenolics decreased. Amphibian abundance decreased with early burns and was higher with LMH. In contrast, small mammal abundance and richness increased without LMH and with time since fire. Richness and foraging of LMH were highest after late burns.</p> <p>These results demonstrate ecosystem-wide effects of LMH, illustrating the importance of considering multiple taxa when designing fire management programs. For example, burning negatively affected amphibians and small mammals and changed vegetation at the same time it increased LMH foraging. In the long-term, this experiment will shed light on interacting effects of fire and LMH on savanna biodiversity and function. </p>
Native plant species show evolutionary responses to invasion by Parthenium hysterophorus in an African savanna
<p>Invasive plant species often competitively displace native plant species but some populations of native plant species can evolve adaptation to competition from invaders and<span> persist in invaded habitats</span>. However, studies are lacking that examine how variation in abiotic conditions in invaded landscapes may affect fitness of native plants that have adapted to compete with invasive plants. I tested whether invasion by <i>Parthenium hysterophorus</i> in an African savanna may have selected for native plant individuals with greater competitive ability than conspecific naïve natives in nutrient-rich and mesic soil conditions. I compared vegetative growth and seed yields of invader-experienced and conspecific naïve native individuals. Invader-experienced natives grew shorter than naïve natives regardless of growth conditions. Nevertheless, the two groups of native plants also exhibited treatment-specific differences in competitive ability. Invader-experienced natives displayed plasticity in seed yield under drought treatment, while naïve natives did not. Moreover, drought treatment enhanced competitive effects of invader-experienced natives on <i>P. hysterophorus</i>, while nutrient enrichment relaxed competitive effects of experienced natives on the invader. The results suggest that <i>P. hysterophorus</i> may have selected for shorter native plant genotypes that also exhibit plasticity in competitive ability under drought conditions.</p>
Large herbivores suppress liana infestation in an African savanna
<p>African savannas are the last stronghold of diverse large-mammal communities, and a major focus of savanna ecology is to understand how these animals affect the relative abundance of trees and grasses. However, savannas support diverse plant life-forms, and human-induced changes in large-herbivore assemblages—declining wildlife populations and their displacement by livestock—may cause unexpected shifts in plant community composition. We investigated how herbivory affects the prevalence of lianas (woody vines) and their impact on trees in an East African savanna. Although scarce (<2% of tree canopy area) and defended by toxic latex, the dominant liana, <i>Cynanchum viminale </i>(Apocynaceae), was eaten by 15 wild large-herbivore species and was consumed in bulk by native browsers during experimental cafeteria trials. In contrast, domesticated ungulates rarely ate lianas. When we experimentally excluded all large herbivores for periods of 8 to 17 years (simulating extirpation), liana abundance increased dramatically, with up to 75% of trees infested. Piecewise exclusion of different-sized herbivores revealed functional complementarity among size classes in suppressing lianas. Liana infestation reduced tree growth and reproduction, but herbivores quickly cleared lianas from trees after the removal of 18-year-old exclosure fences (simulating rewilding). A simple model of liana contagion showed that, without herbivores, the long-term equilibrium could be either endemic (liana-tree coexistence) or an all-liana alternative stable state. We conclude that ongoing declines of wild large-herbivore populations will disrupt the structure and functioning of many African savannas in ways that have received little attention and that may not be mitigated by replacing wildlife with livestock.</p>
Resistance of termite mounds to variation in long-term fire regimes across semi-arid African savannas
<p>1. Fire regimes are expected to change with climate change, resulting in a crucial need to understand the specific ways in which variable fire regimes impact important contributors to ecosystem functioning, such as mound-building termites. Termite mounds and fire are both important agents of savanna ecosystem heterogeneity and functioning, but there is little understanding of how they interact across savanna types. 2. We used very high-resolution LiDAR remote sensing to measure the size, density, and distribution of termite mounds across approximately 1,300 ha of experimental burn plots in four South African savanna landscapes representing a wide range of fire treatments differing in seasonality and frequency of burning. 3. In nutrient-poor granitic savannas, fire had no impact on termite mound size, densities, and spatial distributions. In nutrient-rich basaltic savannas with high mammalian herbivore abundance and intermediate rainfall, very frequent fires caused a decrease in termite mound size, whereas in arid nutrient-rich basaltic savannas, fires that occurred at intermediate frequencies and in transitional seasons (i.e., late dry season and late wet season) decreased the degree of spatial overdispersal exhibited by mounds. 4. Overall, our results suggest that termite mounds are resistant to variation in fire seasonality and frequency, likely indicating that ecosystem services provided by mound-building termites will be unaffected by changing fire regimes. However, consideration of changes to termite mound size and distribution could be necessary for land managers in specific savanna types, such as nutrient-rich soils with high mammalian herbivore abundance.</p>
Data for: Steal the rain: Interception loses and rainfall partitioning by a broad-leaf and a fine-leaf woody encroaching species in a southern African semi-arid savanna
<p><span>Woody plant encroachment (WPE) has been found to alter ecosystem functioning and services in savannas. In rain-limited savannas, increasing woody cover can reduce streamflow and groundwater by altering </span>evapotranspiration rates and rainfall partitioning<span>, but the ecological relevance of this impact is not well known. </span><span>This study quantified the altered partitioning of rainfall by two woody plant structural types (fine- and broad-leaved trees) across a gradient of encroachment in a semi-arid savanna in South Africa. Averaged across both plant functional types, loss of rainfall through canopy interception and subsequent evaporation roughly doubled (from 20.5</span> to <span>43.6% of total rainfall) with a roughly 13-fold increase in woody cover (from 2.4 to </span>31.4 m<sup>2</sup>/ha tree basal cover). Spatial partitioning changes comprised <span>fourfold increases in stemflow (from 0.8</span> to <span>3.9% of total rainfall) and a decline in throughfall proportion of about two-fifths (from 80.2% to 47.3% of total rainfall). </span>Changes in partitioning were dependent on plant functional type; rainfall interception by the fine-leaved multi-stemmed shrub <em>Dichrostachys</em> <em>cinerea</em> was almost double that of the broad-leaved tree <em>Terminalia sericea</em> at the highest levels of woody encroachment (i.e., 49.7% vs 29.1% of total rainfall intercepted at tree basal area of 31.4 m<sup>2</sup>/ha). Partitioning was also dependent on rainfall characteristics, with the proportion of rainfall intercepted inversely related to rainfall event size and intensity. Therefore, increasing tree cover in African grassy ecosystems reduces the amount of canopy throughfall, especially beneath canopies of fine-leaved species in smaller rainfall events. Rainfall interception traits may thus confer a selective advantage, especially for fine-leaved woody plant species in semi-arid savannas. </p>
Effects of long-term fixed fire regimes on African savanna vegetation biomass, vertical structure and tree stem density
<ol> <li><span>Fire plays an integral role in shaping the vegetation structure of savanna ecosystems. However, effects of fire regime characteristics, such as frequency and season of burn, on savanna vegetation structure, biomass and tree abundance across landscape types are largely unknown. </span></li> <li><span>We used high-resolution airborne Light Detection and Ranging (LiDAR) to investigate the long-term effects of fire manipulation on savanna vegetation in Kruger National Park, South Africa. We analysed the effects of fire exclusion and experimental burns every 1, 2, 3, 4 and 6 years and during different seasons on aboveground biomass (AGB), tree stem densities and vegetation vertical height profiles across a rainfall gradient and on contrasting geologies. </span></li> <li><span>Across savanna types, and especially in drier savannas, fire season was more influential for constraining AGB than was fire frequency. Plots experiencing fires during the late- and mid-dry season had 44.50% and 43.60%, respectively, lower AGB relative to unburnt plots than wet-season fires. However, in mesic savannas, fire frequency interacted with fire season to influence AGB: plots subjected to high frequency, dry season fires had 55.35% lower AGB than unburnt plots, whereas plots burnt in the wet season at lower frequencies had lower AGB (24.40% lower than unburnt plots) than plots subjected to high frequency, wet-season fires (13.74% lower AGB than unburnt plots). </span></li> <li><span>Fire regimes had variable effects on tree densities, and effects varied with savanna type. Woody vertical vegetation profiles showed the largest differences in response to dry season fires, with the greatest divergence in vegetation height classes < 5m. </span></li> <li><span><em>Synthesis and applications</em>. Understanding the influence of fire regimes on vegetation structure has important implications for the management of savanna heterogeneity, and for predicting trajectories of change in savanna vegetation as fire regimes vary with climate change. We show that the magnitude of the effect of fire on woody vegetation structure varies with savanna context. Our results suggest that heterogeneous vegetation structure can be achieved by applying fires in the dry season in mesic savannas, whereas in dry savannas, variation in fire regimes is less consequential for constraining biomass accumulation and altering vegetation structure. </span></li> </ol>
Protecting the resource: an assessment of mitigation methods used to protect large trees from African elephant impact in a savanna system
<p>African elephants (<em>Loxodonta africana</em>) can alter the structural components of savanna ecosystems, often through the reduction of the large tree (>5 m height) cover component. Elephant impact can be amplified in small, protected areas, or areas where water is readily available to elephants. One management option is to protect large trees directly using applied mitigation methods to limit elephant impact. In this paper, we assessed and compared the effectiveness and logistical requirements of four mitigation methods that have been applied to protect large trees from elephant impact in South Africa's Greater Kruger National Park - namely African honeybees (<em>Apis mellifera scutellata</em>) in beehives; creosote oil in glass jars, concrete pyramids arranged in circles around trees, as well as wire-netting the trees' main stems. For each method, elephant impact levels and tree mortality rates were measured over a 2–5-year period depending on the method in use. Sample sizes ranged from 43 to 59 trees per mitigation method, with a comparable control, which was a tree of the same species and morphological dimensions but lacking any mitigation application. Beehives were the most effective method at reducing tree loss, significantly reducing tree mortality from 34% (6.8%/year) in control trees to only 10% (2%/year) over the five-year experimental period. However, beehives were the most expensive method to apply to a tree, although this cost can be compensated through honey sales. Concrete pyramids reduced tree loss when the combined pyramid radius was >1.5 m in length, whilst wire-netting was effective against bark-stripping by elephants but was still vulnerable to heavier forms of impact such as uprooting and stem snapping. Creosote jars did not prevent elephants from impacting treated trees. Our results provide managers with a toolkit for protecting large trees against elephant impact, commenting on both the efficacy and the logistical constraints for each method.</p>
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Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.