Tragelaphus Strepsiceros Research Articles

Roles of host and environment in shift of primary anthrax host species in Kruger National Park.

Environmental and climatic factors, as well as host demographics and behaviour, significantly influence the exposure of herbivorous mammalian hosts to pathogens such as Bacillus anthracis, the causative agent of anthrax. Until the early 1990s in Kruger National Park (KNP), kudu (Tragelaphus strepsiceros) was the host species most affected by anthrax, with outbreaks occurring predominantly in the dry season, particularly during drought cycles. However, the most affected host species has shifted to impala (Aepyceros melampus), with more frequent anthrax outbreaks during the wet season. This study investigates the roles of environmental variation and other host species in this shift. Temporal trends in environmental variables such as precipitation, soil moisture, temperature, and normalised difference vegetation index (NDVI) were analyzed in relation to anthrax occurrence (presence/ absence and counts). Additionally, correlations between host species' densities and anthrax mortalities over time were examined. Anthrax cases in 1990 were concentrated in the central and northern regions of KNP(excluding Pafuri), primarily affected kudus; while subsequent mortalities affected mostly impala and were restricted to the far north, in Pafuri. Significant correlations were found between kudu anthrax mortality and a decrease in NDVI, average temperature, SPI-6 and SPI-12 (Standardised Precipitation Index in various time intervals. Conversely, anthrax occurrence in impalas was associated with a decline in SPI-3, and temperature rise, with increased mortality during the rainy season. Elephant density correlated negatively with kudu mortality, but a positive correlation with both impala mortality and impala density. The study concludes that environmental variables and species' densities may alter the diversity and frequency of hosts exposed to B. anthracis. Climate extremes and alterations therein may exacerbate anthrax severity by modifying species susceptibility and their probability of exposure over time.

Effects of human disturbance on the distribution and abundance of large mammals in Abijata-Shalla Lakes National Park, Ethiopia

The increasing human pressure has threatened wildlife conservation, even in protected areas. However, findings reporting the effects of human on wildlife conservation are not consistent. This study aimed to investigate the effect of human disturbance on the distribution and abundance of mammals in Abijata-Shalla Lakes National Park considering the consumptive and non-consumptive modes of human activities. The study was conducted from September 2017 to February 2018 in three selected sites, which were stratified based on human disturbance as nature conserved areas, sites engaged in consumptive livelihood, and ecotourism sites. Data were collected using a line transect method. The distribution and abundance data were analyzed using Chi-square tests and one-way ANOVA, respectively. There was a significant difference on the distribution of target wild animals in the selected sites; greater kudu (P < 0.001), warthog (P < 0.01), and bohor reedbuck (P = 0.03) were highest in the “nature conserved” site. Human disturbance also significantly affected the abundance of warthog (P = 0.028), greater kudu (P < 0.001), and bohor reedbuck (P = 0.024). Greater kudu distribution was limited in nature conserved site. However, Warthog and Bohor Reedbuck were distributed in all sampling sites; nature conserved sites hold the highest population abundance. The results indicate that consumptive local livelihood and ecotourism disturbances adversely affected the distribution and abundance of mammals relative to the nature reserved site. However, ecotourism favored some mammal species from the consumptive local people’s livelihood activities. Thus, to reduce the impact of human disturbances on wildlife conservation, monitoring and controlling the level of human disturbance is urgent. Sustainable practices such as community engagement, awareness creation and alternative livelihood options should be proposed.

How African Ungulates Respond to Tourist Vehicles in Kruger National Park

ABSTRACTManagers of protected areas need to balance how they use or preserve their resources, especially regarding ‘road ecology’. This study focuses on Kruger National Park's (KNP) common ungulates’ response to tourist vehicles. We answered the following questions for impala, zebra, giraffe, blue wildebeest, greater kudu and steenbok: What mediates animal flight and flight distance from a vehicle? How much of KNP is affected by roads? Are ungulates using or avoiding roads? We sampled 55.9% of KNP's tourist roads, where we approached animals and determined whether and how far they fled. We georeferenced sightings and estimated the amount of land area along KNP's tourist roads where animals would be expected to flee from vehicles. Of 517 animal sightings, Impala were sighted most (263) and steenbok least (32). Impala had the highest flight propensity (42.6%) and wildebeest lowest (13%). Steenbok were found closest to the road (22.13 m) and wildebeest furthest (77.6 m). Impala had the closest tolerance distance (16.63 m), with zebra furthest (44.74 m). Impala fled the least distance (9.93 m) and zebra fled furthest (24.52 m). Binary logistic regressions (BLRs) showed that all species fled more consistently when closer to the road. The amount of KNP affected by animal flight based on BLRs was largest for zebra (2.32% of the park) and smallest for kudu (0.84%). Impala used the first 10 m of the roadside more than expected and 10–20 m from the road less. KNP's ungulates are habituated to vehicles since flight propensity was low, distribution analysis showed no‐road avoidance, flight distance was short, and animals &gt; 50 m from the road generally do not flee. Given the amount of KNP that is already affected by vehicle traffic, as tourism increases, the land solely devoted to wildlife will necessarily decrease. This study aims to provide information for the best management of roads and traffic in KNP.

Bacillus anthracis in South Africa, 1975–2013: are some lineages vanishing?

The anthrax-causing bacterium Bacillus anthracis comprises the genetic clades A, B, and C. In the northernmost part (Pafuri) of Kruger National Park (KNP), South Africa, both the common A and rare B strains clades occur. The B clade strains were reported to be dominant in Pafuri before 1991, while A clade strains occurred towards the central parts of KNP. The prevalence of B clade strains is currently much lower as only A clade strains have been isolated from 1992 onwards in KNP. In this study 319 B. anthracis strains were characterized with 31-loci multiple-locus variable-number tandem repeat analysis (MLVA-31). B clade strains from soil (n = 9) and a Tragelaphus strepsiceros carcass (n = 1) were further characterised by whole genome sequencing and compared to publicly available genomes. The KNP strains clustered in the B clade before 1991 into two dominant genotypes. South African strains cluster into a dominant genotype A.Br.005/006 consisting of KNP as well as the other anthrax endemic region, Northern Cape Province (NCP), South Africa. A few A.Br.001/002 strains from both endemic areas were also identified. Subclade A.Br.101 belonging to the A.Br.Aust94 lineage was reported in the NCP. The B-clade strains seems to be vanishing, while outbreaks in South Africa are caused mainly by the A.Br.005/006 genotypes as well as a few minor clades such as A.Br.001/002 and A.Br.101 present in NCP. This work confirmed the existence of the rare and vanishing B-clade strains that group in B.Br.001 branch with KrugerB and A0991 KNP strains.

Direct comparative assessment of radial and transect surveys to document wild mammal activity across diverse habitat types

AbstractWild mammals are often difficult to directly observe, especially in woodland and forest habitats with dense vegetation, so surveys of largely indirect signs of their activities (e.g. tracks and spoor) are often a more practical option for monitoring populations. This study compared two different approaches to surveying largely indirect indicators of activity by a range of wild mammals across a gradient of ecosystem integrity in southern Tanzania. Surveys of all such signs of wild mammal activity detected around all identifiable surface water bodies within a 2 km radius of 32 convenient camping locations with perennial surface water were complemented on alternative days with similar surveys along transects between each camp and the next camp that required similar time and effort. For most of the wild mammal species detected, radial surveys around water bodies proved more sensitive than those along transects between them, because the former approach samples distinct and convenient locations that attract most animal species. Transect surveys were found to be more sensitive for only sable (Hippotragus niger) and spotted hyaena (Crocuta crocuta), which are known to routinely commute considerable distances across their home ranges, and for greater kudu (Tragelaphus strepsiceros) that seldom drink surface water.

New fossil Bovidae (Mammalia: Artiodactyla) from Kromdraai Unit P, South Africa and their implication for biochronology and hominin palaeoecology

Kromdraai is a Plio-Pleistocene site located in the Cradle of Humankind (Gauteng Province, South Africa). It has produced diverse and abundant faunal assemblages and key hominin specimens like the holotype of Paranthropus robustus and early Homo. We provide the first taxonomic study of the Bovidae Family from the hominin-bearing Unit P at Kromdraai and discuss its potential to unravel its paleoecological context. We describe the presence of an unknown medium-sized buffalo (Syncerus sp.) that could be closely related to S. acoelotus. The bovid assemblage from Kromdraai Unit P combines older Plio-Pleistocene (Gazella gracilior, Makapania broomi, Numidocapra cf. porrocornutus) and younger Pleistocene taxa (Tragelaphus strepsiceros, Oreotragus oreotragus, Raphicerus campestris, Damaliscus lunatus). Overall, these bovid species indicate a grassland-dominated environment for Unit P. Comparisons with other Plio-Pleistocene South African sites indicate that Australopithecus was associated with woodland and closed-wet environment-adapted taxa, whereas Homo was found in association with bovid species adapted to open and dry environments. In contrast, the assemblages associated with Paranthropus show an extensive range of environmental adaptation among the bovids. The biochronology indicates that Kromdraai Unit P accumulated between 2.9 and 1.8 Ma. If Kromdraai Unit P were to be confirmed to date to the older end of this scale, it would provide the earliest appearance of Paranthropus robustus, Numidocapra, and Damaliscus in southern Africa.

Using the multivariate Hawkes process to study interactions between multiple species from camera trap data.

Interspecific interactions can influence species' activity and movement patterns. In particular, species may avoid or attract each other through reactive responses in space and/or time. However, data and methods to study such reactive interactions have remained scarce and were generally limited to two interacting species. At this time, the deployment of camera traps opens new opportunities but adapted statistical techniques are still required to analyze interaction patterns with such data. We present the multivariate Hawkes process (MHP) and show how it can be used to analyze interactions between several species using camera trap data. Hawkes processes use flexible pairwise interaction functions, allowing us to consider asymmetries and variations over time when depicting reactive temporal interactions. After describing the theoretical foundations of the MHP, we outline how its framework can be used to study interspecific interactions with camera trap data. We design a simulation study to evaluate the performance of the MHP and of another existing method to infer interactions from camera trap-like data. We also use the MHP to infer reactive interactions from real camera trap data for five species from South African savannas (impala Aepyceros melampus, greater kudu Tragelaphus strepsiceros, lion Panthera leo, blue wildebeest Connochaetes taurinus and Burchell's zebra Equus quagga burchelli). The simulation study shows that the MHP can be used as a tool to benchmark other methods of interspecific interaction inference and that this model can reliably infer interactions when enough data are considered. The analysis of real data highlights evidence of predator avoidance by prey and herbivore-herbivore attraction. Lastly, we present the advantages and limits of the MHP and discuss how it can be improved to infer attraction/avoidance patterns more reliably. As camera traps are increasingly used, the multivariate Hawkes process provides a promising framework to decipher the complexity of interactions structuring ecological communities.

Modeling the drivers of large herbivore distribution in human‐dominated southern African savannas

AbstractAfrican savanna ecosystems are home to the world's richest large herbivore (LH) assemblages. However, its landscapes are changing faster than any other region on Earth due to human activities and natural events. Therefore, understanding the factors influencing the distribution of LH in these human‐dominated environments is crucial for decision‐making on wildlife and habitat management. We combined ecological aerial surveys, camera trap, and dung count data to investigate how ecological (habitat types, perennial rivers, and rainfall) and anthropogenic (human settlements and cattle grazing areas) factors influence the distribution of LH species in Limpopo National Park (LNP). We used generalized linear models fitting binary logistic regression models to distinguish 25‐km2 cells occupied (where the species were detected) by elephants (Loxodonta africana), buffalos (Syncerus caffer), zebras (Equus quagga), kudus (Tragelaphus strepsiceros), nyalas (Tragelaphus angasii), and impalas (Aepyceros melampus) from unoccupied regions (where the species were not detected) in the LNP landscape. We found that habitat type and rainfall were the most influential factors shaping the pattern of LH distribution in the LNP, except for elephants, whose prevalence was not associated with rainfall. The prevalence of zebras was positively associated with the proximity to perennial rivers, while kudus avoided these areas. While some species (zebras, kudus, and impalas) tended to avoid settlements, others (elephants, buffalos, and nyala) seemed attracted to settlements. Cattle grazing areas were the worst predictors of the distribution of all study species. Our results disclosed the role of ecological factors for the distribution of LH and showed that anthropogenic disturbances seemed to either (partially) prevent the occurrence of LH or show the potential for human–wildlife conflict risk in the study area. Therefore, the results highlight the need to investigate/quantify the potential human–wildlife conflict risk at finer spatial scales to improve future management.

Epidemiology and diversity of gastrointestinal tract helminths of wild ruminants in sub-Saharan Africa: a review.

This review summarises studies on distribution, diversity, and prevalence of gastrointestinal helminth infections in wild ruminants in sub-Saharan Africa. The results showed that109 gastrointestinal tract (GIT) helminth species or species complexes were recorded in 10 sub-Saharan African countries. South Africa reported the highest number of species because most studies were carried out in this country. Eighty-eight nematode species or species complexes were recorded from 30 wild ruminant species across eight countries. The genus Trichostrongylus recorded the highest number of species and utilised the highest number of wild ruminant species, and along with Haemonchus spp., was the most widely distributed geographically. Fifteen trematode species or species complexes were reported from seven countries. The genus Paramphistomum recorded the highest number of species, and Calicophoron calicophoron was the most commonly occurring species in sub-Saharan African countries and infected the highest number of hosts. Six cestode species or species complexes from one family were documented from 14 wild hosts in seven countries. Moniezia spp. were the most commonly distributed in terms of host range and geographically. Impala were infected by the highest number of nematodes, whilst Nyala were infected by the highest number of trematode species. Greater kudu and Impala harbored the largest number of cestodes. The prevalence amongst the three GIT helminths taxa ranged between 1.4% and 100% for nematodes, 0.8% and 100% for trematodes, and 1.4% and 50% for cestodes. There is still limited information on the distribution and diversity of GIT helminths in wild ruminants in most sub-Saharan African countries.

Development of conjugated secondary antibodies for wildlife disease surveillance.

Disease monitoring in free-ranging wildlife is a challenge and often relies on passive surveillance. Alternatively, proactive surveillance that relies on the detection of specific antibodies could give more reliable and timely insight into disease presence and prevalence in a population, especially if the evidence of disease occurs below detection thresholds for passive surveillance. Primary binding assays, like the indirect ELISA for antibody detection in wildlife, are hampered by a lack of species-specific conjugates. In this study, we developed anti-kudu (Tragelaphus strepsiceros) and anti-impala (Aepyceros melampus) immunoglobulin-specific conjugates in chickens and compared them to the binding of commercially available protein-G and protein-AG conjugates, using an ELISA-based avidity index. The conjugates were evaluated for cross-reaction with sera from other wild herbivores to assess future use in ELISAs. The developed conjugates had a high avidity of >70% against kudu and impala sera. The commercial conjugates (protein-G and protein-AG) had significantly low relative avidity (<20%) against these species. Eighteen other wildlife species demonstrated cross-reactivity with a mean relative avidity of >50% with the impala and kudu conjugates and <40% with the commercial conjugates. These results demonstrate that species-specific conjugates are important tools for the development and validation of immunoassays in wildlife and for the surveillance of zoonotic agents along the livestock-wildlife-human interface.

Keeping cool on hot days: activity responses of African antelope to heat extremes

Long-lived organisms are likely to respond to a rapidly changing climate with behavioral flexibility. Animals inhabiting the arid parts of southern Africa face a particularly rapid rise in temperature which in combination with food and water scarcity places substantial constraints on the ability of animals to tolerate heat. We investigated how three species of African antelope—springbok Antidorcas marsupialis, kudu Tragelaphus strepsiceros and eland T. oryx—differing in body size, habitat preference and movement ecology, change their activity in response to extreme heat in an arid savanna. Serving as a proxy for activity, dynamic body acceleration data recorded every five minutes were analyzed for seven to eight individuals per species for the three hottest months of the year. Activity responses to heat during the hottest time of day (the afternoons) were investigated and diel activity patterns were compared between hot and cool days. Springbok, which prefer open habitat, are highly mobile and the smallest of the species studied, showed the greatest decrease in activity with rising temperature. Furthermore, springbok showed reduced mean activity over the 24 h cycle on hot days compared to cool days. Large-bodied eland seemed less affected by afternoon heat than springbok. While eland also reduced diurnal activity on hot days compared to cool days, they compensated for this by increasing nocturnal activity, possibly because their predation risk is lower. Kudu, which are comparatively sedentary and typically occupy shady habitat, seemed least affected during the hottest time of day and showed no appreciable difference in diel activity patterns between hot and cool days. The interplay between habitat preference, body size, movement patterns, and other factors seems complex and even sub-lethal levels of heat stress have been shown to impact an animal's long-term survival and reproduction. Thus, differing heat tolerances among species could result in a shift in the composition of African herbivore communities as temperatures continue to rise, with significant implications for economically important wildlife-based land use and conservation.

COMPARING ANTIBIOTIC RESISTANCE IN FREE-RANGING VS. CAPTIVE AFRICAN WILD HERBIVORES.

Antimicrobial resistance (AMR) is a critical challenge of the 21st century for public and animal health. The role of host biodiversity and the environment in the evolution and transmission of resistant bacteria between populations and species, and specifically at the wildlife-livestock-human interface, needs to be further investigated. We evaluated the AMR of commensal Escherichia coli in three mammalian herbivore species-impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), and plains zebra (Equus quagga)-targeting populations living under two conditions: captivity (French zoos) and free ranging (natural and private parks in Zimbabwe). From 137 fecal samples from these three host species, 328 E. coli isolates were isolated. We measured the AMR of each isolate against eight antibiotics, and we assessed the presence of AMR genes and mobile genetic element class 1 integrons (int1). Isolates obtained from captive hosts had a higher probability of being resistant than those obtained from free-ranging hosts (odds ratio, 293.8; confidence interval, 10-94,000). This statistically higher proportion of AMR bacteria in zoos than in natural parks was especially observed for bacteria resistant to amoxicillin. The percentage of int1 detection was higher when isolates were obtained from captive hosts, particularly captive impalas. Ninety percent of bacterial isolates with genes involved in antibiotic resistance also had the int1 gene. The sul1, sul2, blaTEM, and stra genes were found in 14, 19, 0, and 31%, respectively, of E. coli with respective antibiotic resistance. Finally, plains zebra carried AMR significantly more often than the other species.

Remote monitoring of short‐term body mass variation in savanna ungulates

AbstractLarge herbivores in seasonal environments often experience mass variation due to temporal changes in the availability of critical resources like water and forage, as well as due to breeding events. Yet the documentation of mass variation in mammals of highly seasonal savanna habitats, which host the highest densities of grazing ungulates globally, has rarely been explored. Here, we showcase a method to evaluate seasonal mass variation in bovids. Our method used mineral‐baited scales and camera traps to enable us to track the body mass of three species through a period of wet and dry seasons in a South African savanna ecosystem. To illustrate one potential application of the method, we related body mass data to time, weather and resource availability. This showed that individuals altered their body masses markedly between seasons with, for example, female Kudu (Tragelaphus strepsiceros) gaining, on average, &gt;21 kg over the 15‐week wet‐season period in 1 year. These changes were positively related to factors such as vegetation productivity (assessed using NDVI) and the frequency of rains. This method enables easy, non‐lethal and non‐invasive acquisition of mass data. The equipment is easy to deploy concurrently over large areas. Monitoring by this method has a variety of possible applications, potentially providing a useful early‐warning indicator of body condition to inform management, or providing information about ecological states, such as parturition or the reproductive effort of males. Given the longer and harsher dry seasons experienced in many arid systems in recent decades, and projected in future, this method may provide a straightforward means of monitoring long‐term body condition in animals as a result of environmental change.

Between hunter and climate: the effects of hunting and environmental change on fecal glucocorticoid metabolite levels in two sympatric ungulate species in the Ruaha-Rungwa ecosystem, Tanzania.

Understanding the drivers of animal population decline is a key focus of conservation biologists. Anthropogenic activities such as hunting have long been established as potentially detrimental to a population's persistence. However, environmental perturbations such as increased temperature variability, exacerbated by climate change, can also have important effects on animal populations. Animals can respond to these challenges by adjusting both their behavior and physiology. We measured fecal glucocorticoid metabolites (FGMs) of common impala (Aepyceros melampus) and greater kudu (Tragelaphus strepsiceros), both currently in stable populations, to examine effects of hunting, forage availability, daily variability in temperature and group size on their physiological stress response. The study was conducted across two adjacent protected areas, (i) one non-hunted area (Ruaha National Park; RNP) and (ii) one area used for trophy hunting (Rungwa Game Reserve; RGR). Both impala and kudu had significantly higher FGM levels in the area that allows hunting, while FGM levels decreased with increasing forage availability and increasing daily temperature. Moreover, impala (but not kudu) had lower FGM levels with larger group sizes. Our results indicate that the management regime can significantly alter the physiological state of wild ungulate populations. We also highlight the importance of considering the combined effects of anthropogenic, environmental and social contexts when studying the stress response of wild populations. Our results emphasize the value of protected areas and continued monitoring of hunting quota in order to maintain ungulate populations that are less vulnerable to population declines.

Diet of spotted hyaenas (Crocuta crocuta) on farmlands in Namibia

Although their ecology has been well studied across their range, spotted hyaena (Crocuta crocuta) diets, especially within Namibia, are understudied when compared to other large African carnivores in southern Africa. Large carnivores outside of protected areas often faces persecution by farmers as they are often perceived as being livestock killers and spotted hyaenas on arid farmlands in Namibia does not escape this prejudice. Here we investigated the scat composition of spotted hyaenas outside of protected areas on farmlands in south-western parts of Namibia. A total of 53 scat samples were collected from which 203 hair samples were used for identification purposes. Our results indicate that 69.46% of hairs in scat were of wildlife species whilst 30.54% of hairs were from domesticated species. The asymptote reached also suggested that 53 scat samples were sufficient to describe the spotted hyaeans's diet in this particular area. We suspect that an outbreak of rabies in the study area as well as anthropogenic food sources could have influenced prey consumption. As the majority of prey consumed were of wildlife species (such as kudu Tragelaphus strepsiceros and Hartmann's Mountain zebra Equus zebra hartmannae) it is suggested that should the natural prey base be maintained livestock predation could be mitigated. We recommend that future researchers investigate the diet composition of the only other apex predator in this study area, leopards (Panther pardus) which could describe the prey selection and dietary overlap between these two large carnivores.

Effects of fences and fence gaps on the movement behavior of three southern African antelope species

Globally, migratory ungulates are affected by fences. While field observational studies reveal the amount of animal–fence interactions across taxa, GPS tracking-based studies uncover fence effects on movement patterns and habitat selection. However, studies on the direct effects of fences and fence gaps on movement behavior, especially based on high-frequency tracking data, are scarce. We used GPS tracking on three common African antelopes (Tragelaphus strepsiceros, Antidorcas marsupialis, and T. oryx) with movement strategies ranging from range residency to nomadism in a semi-arid, Namibian savanna traversed by wildlife-proof fences that elephants have regularly breached. We classified major forms of ungulate–fence interaction types on a seasonal and a daily scale. Furthermore, we recorded the distances and times spent at fences regarding the total individual space use. Based on this, we analyzed the direct effects of fences and fence gaps on the animals’ movement behavior for the previously defined types of animal–fence interactions. Antelope-fence interactions peaked during the early hours of the day and during seasonal transitions when the limiting resource changed between water and forage. Major types of ungulate–fence interactions were quick, trace-like, or marked by halts. We found that the amount of time spent at fences was highest for nomadic eland. Migratory springbok adjusted their space use concerning fence gap positions. If the small home ranges of sedentary kudu included a fence, they frequently interacted with this fence. For springbok and eland, distance traveled along a fence declined with increasing utilization of a fence gap. All species reduced their speed in the proximity of a fence but often increased their speed when encountering the fence. Crossing a fence led to increased speeds for all species. We demonstrate that fence effects mainly occur during crucial foraging times (seasonal scale) and during times of directed movements (daily scale). Importantly, we provide evidence that fences directly alter antelope movement behaviors with negative implications for energy budgets and that persistent fence gaps can reduce the intensity of such alterations. Our findings help to guide future animal–fence studies and provide insights for wildlife fencing and fence gap planning.

A phylogeographic assessment of the greater kudu (Tragelaphus strepsiceros) across South Africa

The greater kudu (Tragelaphus strepsiceros) is widespread throughout South Africa and occurs in higher densities in the north-eastern regions, with isolated populations in the Eastern Cape Province and in the Kimberley area in the Northern Cape Province. This study aimed to assess the phylogeographic structure of regional South African greater kudu groups, based on neutral mitochondrial DNA regions as well as adaptive variation. A total of 116 kudu were sampled from across the South African distribution range, separated by geographic features and distance, from six South African provinces. Sampling was mainly based on skin samples collected from taxidermists. Genetic diversity and differentiation were quantified using sequence data from the mitochondrial control region (mtDNA CR) and the heat shock protein subunit 5 (HSPA5) gene. Short tandem repeat (STR) sequences were identified at the 3′-UTR of the bone morphogenetic protein 4 (BMP4) gene and used for downstream analyses. Twenty-six haplotypes were identified from the CR dataset, three for the HSPA5 region, and 14 alleles were identified for the BMP4 STR. The CR phylogenetic analyses identified two distinct genetic clades representing an Eastern and Western group respectively. Molecular divergence dating identified the most recent common ancestor of the Eastern and Western South African kudu clades as older (2.237 Mya) than some well-known African antelope species. This result was consistent with the HSPA5 and BMP4 results. Environmental selective pressures, such as rainfall and ambient temperature, were also identified as possible driving forces for evolution at the HSPA5 gene region. Overall, these results can provide support for future management decisions to ensure the conservation of natural patterns of diversity in this majestic antelope species in South Africa.

Facultative cleaning of spiral-horned antelope by the African paradise flycatcher (Terpsiphone viridis).

In cleaning associations, individuals known as “cleaners” remove and feed on parasites and pests found on, or around, other animals known as “clients.” While best documented in marine environments and as mutualisms, cleaning associations are widespread in terrestrial systems and range along a spectrum of obligate to facultative associations. In African savannas, cleaning associations primarily comprise facultative interactions between mammals and birds that remove attached parasites. Few reports, however, exist on cleaning associations that involve the removal of unattached pests. In this short note, I report a novel facultative bird–ungulate cleaning association involving the removal of unattached pests, between the African paradise flycatcher (Terpsiphone viridis) and two species of spiral‐horned antelope (Tragelaphus spp.): greater kudu (Tragelaphus strepsiceros) and Cape bushbuck (Tragelaphus sylvaticus). On multiple occasions, I observed African paradise flycatchers hawking flying insects around greater kudu and a Cape bushbuck during the dry season at the Mpala Research Centre in Laikipia, Kenya. These observations document a rare feeding strategy for the African paradise flycatcher and are among the few records on cleaning interactions involving the removal of unattached pests.

Environmental drivers of biseasonal anthrax outbreak dynamics in two multihost savanna systems

AbstractEnvironmental factors are common forces driving infectious disease dynamics. We compared interannual and seasonal patterns of anthrax infections in two multihost systems in southern Africa: Etosha National Park, Namibia, and Kruger National Park, South Africa. Using several decades of mortality data from each system, we assessed possible transmission mechanisms behind anthrax dynamics, examining (1) within‐ and between‐species temporal case correlations and (2) associations between anthrax mortalities and environmental factors, specifically rainfall and the Normalized Difference Vegetation Index (NDVI), with empirical dynamic modeling. Anthrax cases in Kruger had wide interannual variation in case numbers, and large outbreaks seemed to follow a roughly decadal cycle. In contrast, outbreaks in Etosha were smaller in magnitude and occurred annually. In Etosha, the host species commonly affected remained consistent over several decades, although plains zebra (Equus quagga) became relatively more dominant. In Kruger, turnover of the main host species occurred after the 1990s, where the previously dominant host species, greater kudu (Tragelaphus strepsiceros), was replaced by impala (Aepyceros melampus). In both parks, anthrax infections showed two seasonal peaks, with each species having only one peak in a year. Zebra, springbok (Antidorcas marsupialis), wildebeest (Connochaetes taurinus), and impala cases peaked in wet seasons, while elephant (Loxodonta africana), kudu, and buffalo (Syncerus caffer) cases peaked in dry seasons. For common host species shared between the two parks, anthrax mortalities peaked in the same season in both systems. Among host species with cases peaking in the same season, anthrax mortalities were mostly synchronized, which implies similar transmission mechanisms or shared sources of exposure. Between seasons, outbreaks in one species may contribute to more cases in another species in the following season. Higher vegetation greenness was associated with more zebra and springbok anthrax mortalities in Etosha but fewer elephant cases in Kruger. These results suggest that host behavioral responses to changing environmental conditions may affect anthrax transmission risk, with differences in transmission mechanisms leading to multihost biseasonal outbreaks. This study reveals the dynamics and potential environmental drivers of anthrax in two savanna systems, providing a better understanding of factors driving biseasonal dynamics and outbreak variation among locations.

Short duration overnight cattle kraaling in natural rangelands: Does time after kraal use affect their utilization by wildlife and above ground grass parameters?

In east and southern Africa some private ranch owners are corralling (hereafter kraaling) cattle overnight for short periods (for example, seven days) in natural rangelands to create nutrient enriched hotspots which are attractive to large herbivores. However, the effect of season and time after kraal use (alt. age of nutrient enriched hotspots) on large herbivore use of these sites has not been examined. We collated the number of large herbivore sightings per day from camera traps during wet, early and late dry season in nutrient enriched hotspots of varying ages (1, 2, 3 and 4 years) and surrounding vegetation. In addition, above ground grass biomass and height in nutrient enriched hotspots was compared to that of the surrounding vegetation. Furthermore, we tested if repeated grazing in nutrient enriched hotspots stimulated grass compensatory growth. Large herbivore use of nutrient enriched hotspots was similar during wet, early and late dry season. Time after kraal use had a significant effect on mixed feeders (impala and African savanna elephant) utilization of nutrient enriched hotspots but not grazers (zebra and warthog) and browsers (giraffe and greater kudu). Both impala and African savanna elephants mostly used nutrient enriched hotspots one year after kraal use. Aboveground grass biomass and height were higher in surrounding vegetation than in nutrient enriched hotspots. Repeated clipping (proxy for grazing) resulted in compensatory aboveground grass biomass in nutrient enriched hotspots, which declined with time after kraal use. We concluded that nutrient enriched hotspots created through short duration overnight kraaling were important foraging sites for large herbivores.