Explore the vast range of titles available.

Abstract Infanticide has been described across mammal species. Infanticide is thought to be a tactic which increases reproductive opportunities or reduces competition over local resources. Species of the genus Equus exhibit life history traits such as expensive young, long gestation, lactation and dependency, extended inter-birth interval when there is a foal at foot and strong male reproductive skew. These traits suggest infanticide may be present throughout the genus. However, most documented cases of infanticide attempts come from captive populations and rely heavily on indirect accounts in free-roaming populations. Here, we report an infanticide attempt in Cape mountain zebra (Equus zebra zebra). The aggression was perpetrated by multiple bachelor males on two foals belonging to the same family group. The foals were separated from the parent group, chased and harried for a total of 45 minutes before the mothers and herd stallion were able to regain their offspring. We also report three cases of infanticide from necropsy. The injuries sustained by the foals are consistent with infanticide-based injuries documented in other equids species. The timing of these deaths occurs after a stallion turnover. These two cases provide the most conclusive evidence to date that infanticide takes place within mountain zebra.

Effective conservation and species management require an understanding of the causes of poor population growth. Conservation physiology uses biomarkers to identify factors that contribute to low individual fitness and population declines. Building on this, macrophysiology can use the same markers to assess how individual physiology varies with different ecological or demographic factors over large temporal and spatial scales. Here, we use a macrophysiological approach to identify the ecological and demographic correlates of poor population growth rates in the Cape mountain zebra metapopulation. We use two non‐invasive biomarkers: faecal glucocorticoids as a measure of chronic stress, and faecal androgens as an indicator of male physiological status. We found that faecal glucocorticoid concentrations were highest in the spring prior to summer rainfall, and were elevated in individuals from populations associated with low‐quality habitat (lower grass abundance). In addition, faecal androgen concentrations were higher in populations with a high proportion of non‐breeding stallions (where male:female adult sex ratios exceed 2:1) suggesting sex ratio imbalances may intensify male competition. Finally, population growth rate was negatively associated with faecal glucocorticoid concentrations and female fecundity was negatively associated with faecal androgens, indicating a relationship between hormone profiles and fitness. Together, our results provide cross‐population evidence for how poor population growth rates in Cape mountain zebra can be linked to individual physiological biomarkers. More broadly, we advocate physiological biomarkers as indicators of population viability, and as a way to evaluate the impact of variable ecological and demographic factors. In addition, conservation physiology can be used to assess the efficacy of management interventions for this subspecies, and this approach could inform models of species’ responses to future environmental change. A plain language summary is available for this article. Plain Language Summary

Deserts are typically governed by bottom-up forces and are predicted to be further depleted of their resources, exacerbating extinction risk for local wildlife populations. Additionally, human populations living in these ecosystems are predicted to increase, exposing wildlife to additional human-induced top-down constraints and intensifying human-wildlife conflicts. We aim to investigate how surface water availability, forage availability and other landscape factors shape the spatial arrangement of large herbivore populations in a desert region, and to explore wildlife-livestock co-occurrence patterns to inform coexistence strategies that maximize conservation outputs. We fitted Bayesian zero-inflated binomial N-mixture models (Kéry and Royle 2015) to group count data collected over a 4 year period in the northern Namib desert (Iona National Park, Angola), and found that Hartmann’s mountain zebra and gemsbok preferentially forage in suboptimal low productivity flat areas, away from human activities. Conversely, springbok preferentially occurred in more productive and relatively rugged terrain. We also found a reliance of Hartmann’s mountain zebra on natural water sources ( β DistWater = - 1.04 ± 0.26 and β DistWater = - 0.77 ± 0.20 , for dry and wet seasons, respectively), and a weaker reliance by gemsbok ( β DistWater = 0.20 ± 0.10 and β DistWater = - 0.15 ± 0.10 , respectively for dry and wet seasons). Conversely, we found springbok to forage further from available water ( β DistWater = 0.43 ± 0.05 and β DistWater = 0.26 ± 0.06 , for dry and wet seasons, respectively), suggesting this species may be able to balance hydric requirements from dietary water. Our results support that human activities (inc. livestock herding) induce broad scale top-down regulation in landscape use by our target species, which are then susceptible to resource-driven bottom-up forces at a finer scale. These constraints reflect differences between the realized and expected conservation value of Iona National Park, because human-occupied areas force wildlife to suboptimal habitats. Additionally, we found significant stretches of the landscape to be co-occupied by wildlife and livestock, increasing competition for already limited resources. Our results are useful for informing conservation actions, namely through protected area zonation. Securing exclusive access to key resources by wildlife could be of utmost importance to ensure the long-term survival of these species, and to foster sustained human-wildlife coexistence.

Aim: Promoting population growth of genetically distinct subpopulations of Cape mountain zebra (Equus zebra zebra) is crucial to the survival of the subspecies. Several important Cape mountain zebra reserves are dominated by fynbos vegetation, and population growth is limited by a lack of grassland habitat. A fossil ungulate sequence spanning the last c. 18,000 years is examined to understand the long-term history of this conservation challenge. Location: Boomplaas Cave (BPA), South Africa. Methods: The fossil sequence from BPA is examined to reconstruct ungulate community dynamics in relation to climate and vegetation change over the last 18,000 years. Results: Ungulates from 18,000 to 12,000 years ago suggest an expansion of open grasslands that supported a grazing ecosystem dominated by an extinct caprine antelope and equid remains attributed to E. zebra and E. quagga. At the onset of the Holocene, the grazing ungulate community disappears and small browsers and mixed feeders dominate the assemblage, indicating the loss of open grassland vegetation. Several open-habitat grazers go extinct at this time, and Equus persists at much lower abundances. This shift can be explained by global climate change across the Pleistocene—Holocene transition. Main conclusions: The fossil sequence supports contemporary observations indicating that access to open grassland is crucial to maintaining large Cape mountain zebra subpopulations. Although fynbos is abundant throughout the historic range of the Cape mountain zebra, fossil evidence suggests that such vegetation is unlikely to support dense populations. It has been suggested that the acquisition of agricultural lands that were historically converted to open grasslands for livestock could promote Cape mountain zebra population growth. Results presented here support this management option, as the open grasslands in these converted landscapes likely approximate the vegetation structure during latest Pleistocene, when grasslands were widespread and grazing ungulates abundant.

The target of the 2002 IUCN Action Plan for the Cape mountain zebra Equus zebra zebra was for a population of 2,500 animals. We assessed the validity of this goal by reviewing the conservation status of the subspecies and the prospects of achieving larger populations. All subpopulations were identified and data on each were collected by means of a questionnaire survey. The total extant Cape mountain zebra population was found to consist of at least 2,790 individuals in 52 subpopulations. The target number of 2,500 has therefore been exceeded and this success is largely attributable to the private sector, as there are at present double the number of privately owned subpopulations (35) compared to formally protected subpopulations (17) and the percentage of the population on privately owned land rose from 14% in 1998 to 32% in 2009. The security of the subspecies is still of concern, however, as the growing proportion of the metapopulation on private land is more vulnerable to threats associated with small populations and management actions. The total existing area available to the Cape mountain zebra is > 935,191 ha and it could potentially support a considerably larger population. We conclude that the IUCN target is substantially below the potential for recovery of the Cape mountain zebra and we recommend this target be revised in the light of these findings. More comprehensive conservation strategies to address current and potential future threats are also needed.

Large-herbivore migrations occur across gradients of food quality or food abundance that are generally determined by underlying geographic patterns in rainfall, elevation, or latitude, in turn causing variation in the degree of interspecific competition and the exposure to predators. However, the role of top-down effects of predation as opposed to the bottom-up effects of competition for resources in shaping migrations is not well understood. We studied 30 GPS radio-collared wildebeest and zebra migrating seasonally in the Serengeti-Mara ecosystem to ask how predation and food availability differentially affect the individual movement patterns of these co-migrating species. A hierarchical analysis of movement trajectories (directions and distances) in relation to grass biomass, high-quality food patches, and predation risk show that wildebeest tend to move in response to food quality, with little attention to predation risk. In contrast, individual zebra movements reflect a balance between the risk of predation and the access to high-quality food of sufficient biomass. Our analysis shows how two migratory species move in response to different attributes of the same landscape. Counterintuitively and in contrast to most other animal movement studies, we find that both species move farther each day when resources are locally abundant than when they are scarce. During the wet season when the quality of grazing is at its peak, both wildebeest and zebra move the greatest distances and do not settle in localized areas to graze for extended periods. We propose that this punctuated movement in high-quality patches is explained by density dependency, whereby large groups of competing individuals (up to 1.65 million grazers) rapidly deplete the localized grazing opportunities. These findings capture the roles of predation and competition in shaping animal migrations, which are often claimed but rarely measured.

1. African rangelands support diverse ungulate communities whose member species exhibit unique combinations of body morphology and behaviour that have evolved over millions of years to limit the effects of competition and prédation on fitness, and more recently, to cope with people and livestock. The mechanisms by which native ungulates cope with the combined effects of competition, prédation and human disturbance are poorly understood. Addressing this knowledge gap will help guide management and conservation plans for large mammal communities outside of strictly protected areas. 2. We conducted animal counts on line transects and used a spatially explicit distance sampling model to test the influence of bottom-up effects (vegetation), top-down effects from African lion Panthera leo and spotted hyena Crocuta crocuta and human disturbance (livestock density, occupied human settlements) on native ungulate densities and distributions across a multiple-use rangeland in Kenya. We examined five species that varied in body morphology and foraging strategy, including two large-bodied grazers (zebra Equus quagga; wildebeest Connochaetes taurinus), two medium-bodied, mixed-feeders (Grant's gazelle Nanger granti; impala Aepyceros melampus) and one very large-bodied browser (giraffe Giraffa camelopardalis tippelskirchi). 3. Densities and distributions of all species varied across available land-use types, with bottom-up effects (vegetation) and human disturbance having the strongest overall effects. Responses varied by ungulate foraging strategy. Distributions of grazers and the browser (giraffe) changed seasonally, while distributions of mixed-feeders and a grazer (zebra) changed diurnally. 4. At broad spatial scales, ungulates did not respond to long-term variation in predation risk though they have been shown to respond behaviourally to short-term variation in risk. 5. Synthesis and applications. Our results revealed that native ungulates in this multiple-use rangeland occur at densities comparable to many flagship protected area populations. We attribute observed densities to spatial heterogeneity across this landscape that included variation in human land use (community conservation area, seasonal settlements and livestock grazing, permanent settlements) and vegetation (grassland, bushland, woodland) that changed through time (seasonally, diurnally). This variation allowed ungulates to carve out ecological niches while reducing exposure to the potential limiting effects of competition and human disturbance. For some species, securing access to forage resources and avoiding human disturbance may be associated with costs through increased risk of prédation. Our research reveals the trade-offs native ungulates make to cope with changes in forage availability, human disturbance and predation risk, providing important insights to help guide native ungulate conservation efforts in multiple-use rangelands.

Overmarking remains an unstudied topic in juvenile mammals. We have previously documented a very high rate of overmarking by foals in four captive African equid species: mountain zebra (Equus zebra), plains zebra (Equus quagga), Grévy’s zebra (Equus grevyi), and African wild ass (Equus africanus). African equids vary interspecifically in their social organisation. Since differences in social organisation affect many mammalian behaviours, in this study we investigated interspecific differences in overmarking behaviour of foals, analysing only cases where elimination of any other individual was explored by a foal. We hypothesised that the pattern of overmarking by foals should reflect either differences in social organisation of the species or phylogenetic relations among them. We found that in all species very young foals explored mostly maternal eliminations, and this preference declined with increasing age of the foal and reflected the social organisation of the species; the highest overmarking rate was in species with high intragroup aggression (mountain zebra) and lowest in species with low intragroup aggression and which form crèches (African wild ass). Similarly, the rate of overmarking of the mother, as opposed to other herdmates, was associated with social organisation of the respective species. Thus, we found interspecific differences in overmarking by foals, which were associated with variability in social organisation. Since we also revealed differences between African wild ass and zebra behaviour in early stages of ontogeny, we cannot refute the effect of phylogeny on overmarking behaviour. Additionally, our results supported the identity sharing hypothesis as an explanation of overmarking.

The Cape mountain zebra (Equus zebra zebra) is a subspecies of mountain zebra endemic to South Africa. The Cape mountain zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape mountain zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape mountain zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape mountain zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape mountain zebra, especially in the face of habitat and climate change and emerging diseases.

Migrations of most animal taxa are declining as a result of anthropogenic pressures and land-use transformation. Here, we document and characterize a previously unknown multi-country migration of Burchell's zebra Equus quagga that is the longest of all recorded large mammal migrations in Africa. Our data from eight adult female zebras collared on the border of Namibia and Botswana show that in December 2012 all individuals crossed the Chobe River and moved due south to Nxai Pan National Park in Botswana, where they spent a mean duration of 10 weeks before returning, less directly, to their dry season floodplain habitat. The same southward movements were also observed in December 2013. Nxai Pan appeared to have similar environmental conditions to several possible alternative wet season destinations that were closer to the dry season habitat on the Chobe River, and water availability, but not habitat or vegetation biomass, was associated with higher-use areas along the migratory pathway. These results suggest a genetic and/or cultural basis for the choice of migration destination, rather than an environmental one. Regardless of the cause, the round-trip, straight-line migration distance of 500 km is greater than that covered by wildebeest Connochaetes taurinus during their well-known seasonal journey in the Serengeti ecosystem. It merits conservation attention, given the decline of large-scale ecological processes such as animal migrations.