Mammalian Herbivores Research Articles

Folded: A toolkit to describe mammalian herbivore dentition from 2D images

Abstract Dental morphology is a major aspect of ecological and evolutionary studies of both extant and fossil mammalian species. Mammalian dentitions are diverse feeding systems that can be defined through continuous numerical descriptors of the enamel pattern. We developed a comprehensive toolkit to quantify complex occlusal enamel patterns from two‐dimensional images of herbivore mammals, widespread in the scientific literature, in form of three novel enamel complexity descriptors: two‐dimensional orientation patch count (2D OPC), enamel folding (EF), and enamel thickness (ET). Previously proposed parameters such as occlusal enamel index or indentation index are implemented as well. The current method is devised for extracting continuous variables of enamel complexity from macro and microherbivore mammalian species with conspicuous wear facets. A general case study is proposed using two clades within the Family Rhinocerotidae containing species regarded as hypsodonts. The results show that antagonist dental adaptations were achieved through disparate evolutionary strategies in both groups. To test the robustness of this tool under different practical scenarios, other mammalian groups have been evaluated as well. Additional sensitivity analyses include the impact of image size, rotation, or differences in dental wear. Our approach differs from previous 2D techniques in its affordability, versatility, and control over individual regions within each tooth while delivering continuous numerical data. Additionally, the 2D reference images required as input are widespread in the literature and easier to process in comparison to 3D data alternatives.

Phylogenetic group and virulence profile classification in Escherichia coli from distinct isolation sources in Mexico.

Escherichia coli is a leading cause of human enteric diseases worldwide. The rapid and accurate causal agent identification to a particular source represents a crucial step in the establishment of safety and health measures in the affected human populations and would thus provide insights into the relationship of traits that may contribute for pathogen persistence in a particular reservoir. The objective of the present study was to characterize over two hundred E. coli strains from different isolation sources in Mexico by conducting a correspondence analysis to explore associations with the detected phylogenetic groups. The results indicated that E. coli strains, recovered from distinct sources in Mexico, were classified into phylogroups B1 (35.8%), A (27.8%), and D (12.3%) and were clustered to particular clades according to the predicted phylogroups. The results from correspondence analysis showed that E. coli populations from distinct sources in Mexico, belonging to different phylogroups, were not dispersed randomly and were associated with a particular isolation source. Phylogroup A was strongly associated with human sources, and the phylogroup B1 showed a significant relationship with food sources. Additionally, phylogroup D was also related to human sources. Phylogroup B2 was associated with herbivorous and omnivorous mammals. Moreover, common virulence genes in the examined E. coli strains, assigned to all phylogroups, were identified as essential markers for survival and invasion in the host. Although virulence profiles varied among the detected phylogroups, E. coli strains belonging to phylogroup D, associated with humans, were found to contain the largest virulence gene repertoire conferring for persistence and survival in the host. In summary, these findings provide fundamental information for a better characterization of pathogenic E. coli, recovered from distinct isolation sources in Mexico and would assist in the development of better tools for identifying potential transmission routes of contamination.

Museum Pests in Mammal Furs: An Investigation of the Correlation Between Pests and Host Furs

Insects are of great importance in the ecosystem. In some cases, however, they can be directly or indirectly harmful to humans. Pest insects in museums are good examples of such insects. Especially organic cultural heritage is often the target of these pests. To accomplish effective pest control, it is necessary to obtain knowledge on pest species and their effects. In this study, pest specimens including adults, larvae, pupae and exuviae materials (Total: 1323 specimens) were collected from 59 furs belonging to 12 species of mammals in Zoological Collection of University Istanbul (ZMUI). The species of these pests from various life stages were identified and the numbers were recorded. Further analyses were conducted through the means of Corresponding Analysis and a potential correlation between pest species and species of hosting furs was investigated 9 species of museum pests were identified; Anthrenus verbasci (Linnaeus, 1767), Attagenus brunneus Faldermann, 1835, Dermestes maculatus (DeGeer, 1774), Lasioderma serricorne (Fabricius, 1792), Lepisma sp., Monopis sp., Ptinus clavipes Panzer, 1792, Stegobium paniceum (Linnaeus, 1758) and Tineola bisselliella (Hummel, 1823). Among the pest species, Anthrenus verbasci is the species with the highest specimen count in the collection, as well as the most commonly distributed species. Museum pests are mainly observed on the furs of herbivore mammals. This observation is demonstrated with Corresponding Analysis. Also through Corresponding Analysis, a correlation between the species of pest insects and the diets of the species of hosting furs was demonstrated.

THE QUIBAS SITE (MURCIA, SPAIN): NEW HERBIVORES FROM THE EARLY-MIDDLE PLEISTOCENE TRANSITION

The Lower Pleistocene site of Quibas, in Sierra de Quibas (Murcia, Spain) was discovered in 1994 and has since then provided abundant material of typical Epivillafranchian taxa. This biochron belongs to the Early-Middle Pleistocene transition (1.2 – 0.78 Ma), characterised by a change in orbital cyclicity from a 41 kyr cycle to 100 kyr that intensified the climate and culminated in the most important faunal turnover of the Pleistocene regarding large mammals. The Group of Palaeoanthropology of the National Museum of Natural Sciences (CSIC, Spain) and the Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA, Spain) carried out four field seasons from 2015 to 2018. Here we present the large herbivorous mammals recovered from the field, including the first citation of two taxa new to the locality: Stephanorhinus cf. etruscus and Bison cf. voigtstedtensis. We also provide the first description of previously mentioned taxa: Dama cf. vallonnetensis and Sus sp. Together with the remaining herbivores, the faunal community shows a strong European affinity with some regionalism. Compared with other Iberian localities, the site of Quibas stands out for the lack of hominin fossils or any evidence supporting their presence in the area, a peculiar scenario given that the Early-Middle Pleistocene transition broadly speaking sees the arrival of humans into Europe.

Resistance of termite mounds to variation in long-term fire regimes across semi-arid African savannas.

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. We used very high-resolution LiDAR remote sensing to measure the size and distribution of termite mounds across approximately 1300 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. 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. 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.

Small mammal herbivores part 3: taking a dietary history and providing nutritional support

The unique dietary needs of exotic companion mammal herbivores has been thoroughly explored in this series of articles. The veterinary nurse can be well-equipped and is in an excellent position to take a detailed husbandry and nutritional history, which can help to identify nutritional disease and problems with dietary management that may contribute to future pathogenesis. Providing nutritional support in the hindgut fermenter inpatient or outpatient is centred around both restoring the negative energy balance (as the target species will rapidly enter a catabolic state) and providing enough fibre to stimulate gastrointestinal motility.

Light competition drives herbivore and nutrient effects on plant diversity

Enrichment of nutrients and loss of herbivores are assumed to cause a loss of plant diversity in grassland ecosystems because they increase plant cover, which leads to a decrease of light in the understory1–3. Empirical tests of the role of competition for light in natural systems are based on indirect evidence, and have been a topic of debate for the last 40 years. Here we show that experimentally restoring light to understory plants in a natural grassland mitigates the loss of plant diversity that is caused by either nutrient enrichment or the absence of mammalian herbivores. The initial effect of light addition on restoring diversity under fertilization was transitory and outweighed by the greater effect of herbivory on light levels, indicating that herbivory is a major factor that controls diversity, partly through light. Our results provide direct experimental evidence, in a natural system, that competition for light is a key mechanism that contributes to the loss of biodiversity after cessation of mammalian herbivory. Our findings also show that the effects of herbivores can outpace the effects of fertilization on competition for light. Management practices that target maintaining grazing by native or domestic herbivores could therefore have applications in protecting biodiversity in grassland ecosystems, because they alleviate competition for light in the understory.

Diet and habitat of late Miocene herbivore mammals from Nurpur, District Kangra, Himachal Pradesh, India

We present the stable carbon (δ13C) and oxygen (δ18O) isotopic composition of 75 serial samples (tooth enamels) from five mammalian fossil groups, which include giraffids, equids, bovids, tragulids, and suids, to reconstruct their diet and habitat. These mammalian faunas were recovered from a late Miocene Middle Siwalik succession exposed in Nurpur, Himachal Pradesh, India (8.14–5.26 Ma). The average δ13C data of the studied mammals, that is, −13.30 ± 0.71 (giraffids), −11.29 ± 0.63 (equids), −12.68 ± 0.49‰ (bovids), −12.97 ± 1.11 (tragulids), and −12.01 ± 0.47 (suids) indicates a mainly C3 diet with a minor component of C4 grass (up to 17%) and a habitat dominant by forest/woodland. The average δ18O value of giraffids (−5.83 ± 0.85) is slightly enriched as compared to other herbivore mammals, such as equids (−8.85 ± 1.71), bovids (−7.86 ± 0.62‰), tragulids (−8.26 ± 1.92), and suids (−10.65 ± 0.23). It suggests that the browsing giraffids could likely intake water from enriched 18O sources, whereas the other browsing mammals consume water from depleted 18O sources in the local ecosystem. However, the δ18O values indicate the existence of a warm, humid climate and more precipitation in the Siwalik during the late Miocene.

The biodeposition process in native mammals: spatial distribution and influence of waste products on soil fertility in restored and grazed woodland

Mammals have been widely recognized as mobile link species that can vectorize resources across the landscape. In this study, we analyze the biodeposition of waste products egested by native herbivorous mammals of the Monte Desert to document for the first time the implications of the restoration of a native forest on this process. We compared a restored native woodland an adjacent grazing field in terms of the spatial distribution of waste products, the biodiversity of trophic items stored in fecal pellets, and the C:N ratio as a predictor of nutrients supplied to the soil. We found that fecal pellets of mammal species were intermingled and spatially distributed throughout the entire landscape, but they were more abundant in the restoration area, indicating the influence of land management types on the distribution process. The two mammal species presented different feeding strategies; however, the plant species consumed in the grazing field indicate decreased food options for native mammals, meaning a smaller amplitude of their trophic niches under this land management. The low C:N ratio and the high nitrogen pool provided by the pellets in the restoration area suggest a potential benefit to plant communities. However, the higher organic C jointly with the lower C:N ratio observed in fecal pellets of grazing field indicate a low decomposability which could promote the conservation of C in the soil.

Differences in arthropod communities between grazed areas and grazing exclosures depend on arthropod groups and vegetation types

Livestock grazing is one of the most common management practices for grasslands and can greatly affect their biodiversity. However, arthropod diversity response patterns to grazing regimes are difficult to predict. We conducted a short-term grazing exclusion experiment in traditionally managed alkali grasslands in Hungary to investigate differences between grazed and ungrazed vegetation for different arthropod groups. The experiment was laid out in a full factorial design, with twelve 50 × 100 m short-term grazing exclosures in vegetation types with high (alkali wet meadow) and low productivity (alkali steppe). We sampled ground beetles and spiders with pitfall traps and true hoppers by sweep netting. We used vegetation type (wet meadow vs dry steppe), management (grazed vs ungrazed) and their interaction as fixed effects in mixed models. We found higher species richness and activity density of spiders and ground beetles in the more productive wet meadow vegetation, where the community structure of each arthropod group also shifted toward hygrophilous species. Significant interactions between vegetation type and management indicated a dependence of management effects on vegetation types: arthropod community structure shifted towards hygrophilous species in ungrazed meadows, but not in ungrazed steppe sites. True hopper abundance was higher in grazed meadow sites, but lower in grazed steppe sites, compared to ungrazed sites. True hopper community structure shifted toward generalist herbivores in ungrazed sites, regardless of vegetation type. We concluded that vegetation types determine arthropod communities and modulate the effects of grazing on arthropods. Our results suggest that moderate disturbance from low-intensity grazing has a positive or neutral effect in wetter, more productive vegetation, but a negative or neutral effect in drier, less productive vegetation, depending on the arthropod group. Herbivorous insects that dwell on plants are particularly affected by management because they are more susceptible to direct impacts, such as unintentional predation by grazing cattle, and because of asymmetrical competition between mammalian and insect herbivores.

Physical, landscape, and chemical properties of Amazonian interior forest mineral licks.

Mineral licks, sites where animals go to consume soil, are key resources for herbivorous birds and mammals in the Amazon, providing supplemental dietary nutrients and toxin adsorption functions. However, because they are often difficult to find, the properties of mineral licks are poorly understood. Here, we undertake the largest survey of Amazonian mineral licks to date to determine the landscape, physical, and chemical properties of these critical sites. We used a generalized linear mixed-effects modeling framework to assess how soil samples from 83 mineral licks differ from nearby control soils in a series of physical and chemical characteristics, then used Jaccard's index of similarity and a principal component analysis (PCA) to determine how those samples differed among themselves. We found that mineral licks were generally located in specific ranges of landscape variables. Soils from mineral licks had elevated concentrations of almost all minerals measured. There was very little similarity between consumed and control samples, and within each sample type. We suggest that these mineral licks have the potential to provide multiple services to visiting species, demonstrating their ecological importance. The high levels of dissimilarity between samples indicate that a large sample of mineral licks is needed to draw conclusions in studies pertaining to geophagy. We emphasize that studying mammal and bird visitation at these sites could provide critical conservation and physiological information on cryptic and understudied species of Amazonian herbivores.

Loss of grazing by large mammalian herbivores can destabilize the soil carbon pool

Grazing by mammalian herbivores can be a climate mitigation strategy as it influences the size and stability of a large soil carbon (soil-C) pool (more than 500 Pg C in the world's grasslands, steppes, and savannas). With continuing declines in the numbers of large mammalian herbivores, the resultant loss in grazer functions can be consequential for this soil-C pool and ultimately for the global carbon cycle. While herbivore effects on the size of the soil-C pool and the conditions under which they lead to gain or loss in soil-C are becoming increasingly clear, their effect on the equally important aspect of stability of soil-C remains unknown. We used a replicated long-term field experiment in the Trans-Himalayan grazing ecosystem to evaluate the consequences of herbivore exclusion on interannual fluctuations in soil-C (2006 to 2021). Interannual fluctuations in soil-C and soil-N were 30 to 40% higher after herbivore exclusion than under grazing. Structural equation modeling suggested that grazing appears to mediate the stabilizing versus destabilizing influences of nitrogen (N) on soil-C. This may explain why N addition stimulates soil-C loss in the absence of herbivores around the world. Herbivore loss, and the consequent decline in grazer functions, can therefore undermine the stability of soil-C. Soil-C is not inert but a very dynamic pool. It can provide nature-based climate solutions by conserving and restoring a functional role of large mammalian herbivores that extends to the stoichiometric coupling between soil-C and soil-N.

Stable isotope record of Triceratops from a mass accumulation (Lance Formation, Wyoming, USA) provides insights into Triceratops behaviour and ecology

Our understanding of Late Cretaceous dinosaur ecosystems from North America has considerably improved through stable isotope analyses on fossil bones and teeth. Oxygen and carbon stable isotopic compositions of structurally-bound carbonate in these fossil apatites are commonly used to infer variations of ingested water and food sources, which are in turn related to environmental and climatic conditions. Incremental isotopic records potentially provide insights into seasonality and migratory behaviour. So far, these reconstructions are based on vertebrate remains from spatiotemporally diverse datasets. Here, we present oxygen (δ18O) and carbon (δ13C) isotopic records from a large, spatially and temporally well-constrained, Triceratops bonebed from the Upper Maastrichtian Lance Formation (eastern Wyoming. USA). These isotopic compositions allow to elucidate the palaeoecology of these large herbivores and their ecosystem in detail, as well as their habitat use, diet and possible migration. The δ18O signature from incrementally sampled Triceratops teeth reveal relatively low intra-tooth variation (average 1.3 ‰), comparable to contemporaneous dinosaur species as well as modern herbivorous mammals. Average δ13C values (−5.4 ‰) are somewhat higher than for modern C3 plant grazers, and hint towards complex interactions during carbon uptake by non-avian herbivorous dinosaurs. Calculated δ18O of drinking water (−14.8 ‰) combined with the local sedimentology of fine-grained siliciclastic deposits with high total organic and low carbonate contents strongly suggest a freshwater environment. Additionally, the combined average δ18O and δ13C Triceratops isotope signatures indicate a living environment intermediate between inland forests and coastal floodplains, expanding on earlier theories of ornithischian niche partitioning. Our robust dataset provides meaningful tests of habitat and palaeoecological hypotheses for Triceratops, and highlights the application of spatiotemporally well-constrained fossil remains.

Endogenous phthalates as a prospective regulator of interspecific relations in a biocoenosis

It is widely believed that phthalates are xenobiotic pollutants whose prevalence in the environment is associated with their facilitated diffusion from plastic materials. Studies into the effect of synthetic phthalates on living organisms revealed their extremely negative action on the metabolism of animals and humans. The acting mechanism of these compounds is realised through a ligand-receptor pathway. Along with dioxins, polychlorinated biphenyls and similar compounds, phthalates are classified as endocrine disrupters. However, at present, sufficient evidence has been accumulated confirming the natural origin of phthalates. Thus, phthalates were de novo biosynthesised from labelled precursors in an algae culture. These compounds were detected in closed experimental systems, including cell cultures of highest plants, as well as those isolated from a number of bacterial, fungi, lowest and highest plant forms located far from the sources of technogenic pollution. The concept of phthalate biogenesis assumes the action of these compounds on living systems. Phthalates exhibit bactericidal and fungicidal action and compose allelopathic exudates, suppressing the growth of competing plant forms. Phthalates possess insecticidal and repellent properties. An analogy can be traced between the action of phthalates and endocrine disrupters of another chemical category, namely phytoestrogens, which regulate herbivorous mammal populations. A hypothesis is proposed about the biological role of endogenous plant phthalates representing secondary metabolic compounds. Exhibiting predominantly a shielding function, these compounds participate in the network of interactions between plants, animals, fungi and microorganisms. It should be noted that synthetic and endogenous phthalates are characterised by essential stereochemical differences, which can explain their different action on living organisms.

Embedding trait‐based ecology within indigenous knowledge to advance sustainable management of Tibetan rangeland

AbstractQuestionsTraditional pastoralists attribute high numbers of plateau pikas (Ochotona curzoniae) to impoverished soils that favor more and better forage for pika, suggesting a bottom‐up control of pika density. Conversely, government policies focus on excessive numbers of this small mammalian herbivore as the primary top‐down cause of degradation in Tibetan rangeland. Despite concerted campaigns to reduce pika abundance in recent decades, the sustainability of Tibetan rangelands remains uncertain.LocationAlpine meadows on the Tibetan Plateau.MethodsWe proposed a conceptual model based on indigenous knowledge that predicted pika numbers from soil condition and plant traits. At three alpine meadow sites lightly grazed by livestock, we tested whether spatial variation in pika burrow density could be explained by changes in the functional composition of the plant community attributable to species turnover and intraspecific trait variation associated with changes in soil fertility.ResultsDue primarily to intraspecific trait variation, changes in the functional composition of the meadow community accounted for 56%–68% of the spatial variation in pika density, changes in the proportion of plant functional groups for 62%–74%, and changes in edaphic conditions for 71%–82%. Greater pika density was associated with a decline in soil phosphorus availability and a lower‐growing vegetation profile enriched in both the quantity and quality of forage preferred by pikas.ConclusionsThese results, which are in accord with indigenous knowledge, suggest that compensating soil phosphorus losses and maintaining a well‐calibrated grazing rotation can better manage pika populations and improve the sustainability of Tibetan rangelands. By combining trait‐based ecology and traditional knowledge, our study provides new insight into both understanding the dynamic complexity of grazing regimes and managing rangeland sustainability.

The Hoatzin

Joel Cracraft introduces the Hoatzin (Opisthocomus hoazin), an odd and enigmatic bird that defies classification.

Effect of the presence of plateau pikas on the ecosystem services of alpine meadows

Abstract. The activity of small mammalian herbivores influences grassland ecosystem services in arid and semi-arid regions. Plateau pika (Ochotona curzoniae) was considered to be a focal organism to investigate the effect of small mammalian herbivores on meadow ecosystem services in alpine regions. In this study, a home-range scale was used to measure the forage available to livestock, water conservation, carbon sequestration and soil nutrient maintenance (total nitrogen, phosphorus and potassium) in the topsoil layer, and a quadrat scale was used to assess the biodiversity conservation of alpine meadows. This study showed that the forage available to livestock and water conservation was 19 % and 16 % lower in the presence of plateau pikas than in their absence, and biodiversity conservation, carbon sequestration, soil nitrogen and phosphorus maintenance was 15 %, 29 %, 10 % and 8.9 % higher in the presence of plateau pikas than in their absence. In contrast, it had no impact on soil potassium maintenance of meadow ecosystems in alpine regions. The forage available to livestock, biodiversity conservation and soil nutrient maintenance of meadow ecosystems in alpine regions had maximum values as the disturbance intensity of plateau pikas increased; the water conservation tended to decrease linearly with the increasing disturbance intensity of plateau pikas. These results present a pattern of plateau pikas influencing the ecosystem services of meadow ecosystems in alpine regions, enriching our understanding of the small mammalian herbivores in relation to grassland ecosystem service.

Mitochondrial genetic diversity of the Greater Cane rat (Thryonomys swinderianus) populations from the Eastern Arc Mountains ecosystem, Tanzania.

Management of most herbivorous small mammal species considered to be pests in Africa is still challenging partly because of the paucity of information on their biological traits that would help to manage their destructive impacts. This gap also precludes the potential for tapping species with potential food-value to improving the economy of rural communities through, for example, sustainable game farming programs in Africa. This study investigates the genetic diversity and population demography of the African Greater Cane rat (AGC), a rodent pest of crops and game species inhabiting two isolated blocks of the Eastern Arc Mountains (EAMs), Tanzania to contribute to the species management and conservation. We used non-invasive sampling techniques and DNA sequencing of the D-loop region of MtDNA (515bp) from 46 cane rats (Thryonomys swinderianus) samples to characterize the genetic diversity and structure of the species and potential population threats faced in natural habitats. We found 25 haplotypes:15 from Uluguru and 9 from Udzungwa mountains populations, containing 49 polymorphic regions (32 parsimoniously informative and 17 singleton sites). Haplotype diversity (range: 0.849-0.995) did not differ substantially across populations but the median haplotype diversity for Udzungwa South was overall lower than for other populations. Nucleotide diversity averaged 0.00641, 0.01528, 0.0111 and 0.01313, respectively for Udzungwa South, Udzungwa North, Uluguru Rural and Uluguru Urban, suggesting high genetic diversity within the four populations. Analysis of molecular variance (AMOVA) indicated significantly high genetic differences between the four populations (FST = 0.16, p = 0.00098) whereas neutrality test (FU's Fs) values were negative, indicating historical population expansion. Similarly, the Bayesian skyline analysis indicated a recent demographic expansion suggesting limited bottlenecks in the recent past in this population. Our results show the AGC population in EAMs consists of four distinct populations which have experienced a recent population expansion, especially among the urban population due perhaps to influence of urbanization process that may have favored assisted species movements across the rural-urban landscapes. Future research should focus on understanding impact of geographical isolation on the genetic structure and diversity of this species.

Small mammal herbivores part 1: digestive system adaptations to a herbivorous diet

Nutritional disease is common in exotic companion mammals, and the unique dietary adaptations of herbivorous species only compounds this issue. The target species (including lagomorphs, and hystricomorph or caviomorph rodents) exhibit anatomical and physiological adaptations to a plant-based diet that is low in calories and protein, and high in fibre. Digestive tract adaptations such as hypselodont dentition to hindgut fermentation will be reviewed. Veterinary nurses are in an excellent position to counsel pet owners on the appropriate nutrition of their companion animals, and understanding these unique adaptations provides the necessary baseline knowledge to make recommendations.

Integrating herbivore assemblages and woody plant cover in an African savanna to reveal how herbivores respond to ecosystem management.

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 MalaMala Game Reserve, South Africa 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.