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Abstract As we enter the sixth mass extinction, many species that are no longer self‐sustaining in their natural habitat will require ex situ management. Zoos have finite resources for ex situ management, and there is a need for holistic conservation programs between the public and private sector. Ex situ populations of sable antelope, Hippotragus niger, have existed in zoos and privately owned ranches in North America since the 1910s. Unknown founder representation and relatedness has made the genetic management of this species challenging within zoos, while populations on privately owned ranches are managed independently and retain minimal‐to‐no pedigree history. Consequences of such challenges include an increased risk of inbreeding and a loss of genetic diversity. Here, we developed and applied a customized targeted sequence capture panel based on 5,000 genomewide single‐nucleotide polymorphisms to investigate the genomic diversity present in these uniquely managed populations. We genotyped 111 sable antelope: 23 from zoos, 43 from a single conservation center, and 45 from ranches. We found significantly higher genetic diversity and significantly lower inbreeding in herds housed in zoos and conservation centers, when compared to those in privately owned ranches, likely due to genetic‐based breeding recommendations implemented in the former populations. Genetic clustering was strong among all three populations, possibly as a result of genetic drift. We propose that the North American ex situ population of sable antelope would benefit from a metapopulation management system, to halt genetic drift, reduce the occurrence of inbreeding, and enable sustainable population sizes to be managed ex situ.

Congenital peritoneopericardial diaphragmatic hernia was diagnosed in a 2‐week‐old sable antelope (Hippotragus niger) calf with subsequent fatal acute heart failure. Histopathological examination of the lung, liver and heart revealed lesions supportive of acute heart failure that consisted of pulmonary oedema, periacinar hepatocellular necrosis and myocardial degeneration and necrosis. The external pressure on the coronary arteries by the liver and abomasum most likely resulted in ischaemic injury of the cardiomyocytes and the resultant acute heart failure. [ABSTRACT FROM AUTHOR]

Genome-wide assessment of genetic diversity has the potential to increase the ability to understand admixture, inbreeding, kinship and erosion of genetic diversity affecting both captive (ex situ) and wild (in situ) populations of threatened species. The sable antelope (Hippotragus niger), native to the savannah woodlands of sub-Saharan Africa, is a species that is being managed ex situ in both public (zoo) and private (ranch) collections in the United States. Our objective was to develop whole genome sequence resources that will serve as a foundation for characterizing the genetic status of ex situ populations of sable antelope relative to populations in the wild. Here we report the draft genome assembly of a male sable antelope, a member of the subfamily Hippotraginae (Bovidae, Cetartiodactyla, Mammalia). The 2.596 Gb draft genome consists of 136,528 contigs with an N50 of 45.5 Kbp and 16,927 scaffolds with an N50 of 4.59 Mbp. De novo annotation identified 18,828 protein-coding genes and repetitive sequences encompassing 46.97% of the genome. The discovery of single nucleotide variants (SNVs) was assisted by the re-sequencing of seven additional captive and wild individuals, representing two different subspecies, leading to the identification of 1,987,710 bi-allelic SNVs. Assembly of the mitochondrial genomes revealed that each individual was defined by a unique haplotype and these data were used to infer the mitochondrial gene tree relative to other hippotragine species. The sable antelope genome constitutes a valuable resource for assessing genome-wide diversity and evolutionary potential, thereby facilitating long-term conservation of this charismatic species.

As we enter the sixth mass extinction, many species that are no longer self‐sustaining in their natural habitat will require ex situ management. Zoos have finite resources for ex situ management, and there is a need for holistic conservation programs between the public and private sector. Ex situ populations of sable antelope, Hippotragus niger, have existed in zoos and privately owned ranches in North America since the 1910s. Unknown founder representation and relatedness has made the genetic management of this species challenging within zoos, while populations on privately owned ranches are managed independently and retain minimal‐to‐no pedigree history. Consequences of such challenges include an increased risk of inbreeding and a loss of genetic diversity. Here, we developed and applied a customized targeted sequence capture panel based on 5,000 genomewide single‐nucleotide polymorphisms to investigate the genomic diversity present in these uniquely managed populations. We genotyped 111 sable antelope: 23 from zoos, 43 from a single conservation center, and 45 from ranches. We found significantly higher genetic diversity and significantly lower inbreeding in herds housed in zoos and conservation centers, when compared to those in privately owned ranches, likely due to genetic‐based breeding recommendations implemented in the former populations. Genetic clustering was strong among all three populations, possibly as a result of genetic drift. We propose that the North American ex situ population of sable antelope would benefit from a metapopulation management system, to halt genetic drift, reduce the occurrence of inbreeding, and enable sustainable population sizes to be managed ex situ. [ABSTRACT FROM AUTHOR]

Genome-wide assessment of genetic diversity has the potential to increase the ability to understand admixture, inbreeding, kinship and erosion of genetic diversity affecting both captive (ex situ) and wild (in situ) populations of threatened species. The sable antelope (Hippotragus niger), native to the savannah woodlands of sub-Saharan Africa, is a species that is being managed ex situ in both public (zoo) and private (ranch) collections in the United States. Our objective was to develop whole genome sequence resources that will serve as a foundation for characterizing the genetic status of ex situ populations of sable antelope relative to populations in the wild. Here we report the draft genome assembly of a male sable antelope, a member of the subfamily Hippotraginae (Bovidae, Cetartiodactyla, Mammalia). The 2.596 Gb draft genome consists of 136,528 contigs with an N50 of 45.5 Kbp and 16,927 scaffolds with an N50 of 4.59 Mbp. De novo annotation identified 18,828 protein-coding genes and repetitive sequences encompassing 46.97% of the genome. The discovery of single nucleotide variants (SNVs) was assisted by the re-sequencing of seven additional captive and wild individuals, representing two different subspecies, leading to the identification of 1,987,710 bi-allelic SNVs. Assembly of the mitochondrial genomes revealed that each individual was defined by a unique haplotype and these data were used to infer the mitochondrial gene tree relative to other hippotragine species. The sable antelope genome constitutes a valuable resource for assessing genome-wide diversity and evolutionary potential, thereby facilitating long-term conservation of this charismatic species. [ABSTRACT FROM AUTHOR]

The blue buck or blue antelope (Hippotragus leucophaeus) is an extinct antelope endemic to coastal South Africa. With a much wider distribution in the Pleistocene, it was already in decline before European settlement in the region (c. 400 years ago), and it went extinct in the late 18th century. Due to the short time span between its formal description and the time it went extinct, not much is known about its biology or behaviour, and its phylogenetic placement is still inconclusive. Here we sequence the complete mitochondrial genome of the blue buck from a museum-preserved horn. The data generated in this study allowed the placement of the blue buck as sister species to the sable antelope (Hippotragus niger), with a divergence time of 2.8 Myr. The roan antelope (Hippotragus equinus) is sister taxon to this clade, contradicting some earlier findings. [ABSTRACT FROM AUTHOR]

Although being an important conservation tool in Africa, trophy hunting is known to influence risk perception in wildlife species, thus affecting the behaviour and fitness of most targeted species. We studied the effects of trophy hunting on the flight behaviour of impala ( Aepyceros melampus), greater kudu ( Tragelaphus strepsiceros) and sable ( Hippotragus niger) in two closed ecosystems, Cawston Ranch (hunting area) and Stanley and Livingstone Private Game Reserve (tourist area), western Zimbabwe. Using standardized field procedures, we assessed the flight behavioural responses of the three species in two seasons: non-hunting (December-March) and hunting (April-November) between March 2013 and November 2014. We tested the effect of habitat, group size, sex, season, start distance and alert distance on flight initiation distance using linear mixed models. Habitat, group size sex and alert distance did not have any effect on flight initiation distance for the three species. The three species were more alert and displayed longer flight initiation distances in the hunting area compared with the tourist area. Flight initiation distances for the three species were higher during the hunting season for the hunting area and low during the non-hunting season. Flight distances of the three species did not differ between the hunting area and the tourist area. We concluded that trophy hunting increased perceived risk of wild ungulates in closed hunting areas, whereas ungulates in non-hunting areas are less responsive and somehow habituated to human presence. Management plans should include minimum approach distances by tourists as well as establishing seasonal restrictions on special zones to promote species viability. Research aimed at integrating behavioural responses with physiological aspects of target species should be promoted to ensure that managers are able to deal with the behavioural trade-offs of trophy hunting at local and regional scale. [ABSTRACT FROM AUTHOR]

Similar to declines in antelope species across African conservation areas, sable ( Hippotragus niger) at Kgaswane Mountain Reserve, South Africa, has exhibited a negative trend in abundance since 2000. To investigate the cause of decline, we assessed three hypotheses: seasonal forage abundance, habitat conditions and interspecific competition. We considered the evidence for each hypothesis by analysing reserve survey data, rainfall records and historical burn data with hierarchical models that incorporated potential density-dependent effects and environmental covariates. After accounting for the effects of sable abundance, we found that sable population growth was most strongly related to the interspecific competition covariates and to waterbuck ( Kobus ellipsiprymnus) count in particular. Also, the strength of the relationship was shaped by the trend in sable numbers and whether the population was before or after peak abundance: the strongest indication of interspecific competition occurred after sable had reached peak abundance. The interaction between abundance of sable and that of potentially competing species emphasizes the importance of accounting for density-dependent processes, and in particular longer-term phases in abundance, when judging the roles of other factors that affect species abundance. [ABSTRACT FROM AUTHOR]

Sable antelope, H ippotragus niger, populations have declined substantially in Kruger National Park, South Africa despite large-area protection from land use and poaching. Since Africa's large mammal populations are restricted to protected areas, understanding how to manage parks for biological diversity is critically important to the sustainability of faunal populations into the future. To better understand the drivers of sable decline, we analyzed landscapes where herds persist in the Pretoriuskop region of Kruger - identified by GPS collar telemetry data from eight individuals in five herds remaining in this area, and compared them to landscapes where sable herds have recently disappeared. We mapped these landscapes with satellite-based spectral data on vegetation greenness and fire frequency and Carnegie Airborne Observatory LiDAR ( Light Detection and Ranging) data on 3- D vegetation structure. Within their home ranges, sable herds consistently selected areas with high fire frequency, high tree cover and low shrub cover. However, there were no consistent differences in habitat features between the home ranges of current sable herds and areas formerly supporting herds. Locally deteriorating habitat conditions were therefore not responsible for the decline in sables in this region of the park. Our study also illustrates how multi-sensor, 3- D mapping of ecosystems provides a means to assess causes and consequences of changing animal habitats over time. [ABSTRACT FROM AUTHOR]

Land use has major effects on wildlife conservation. We studied variations of sable antelope Hippotragus niger densities between 1990 and 2001 in comparison with various land uses in and around Hwange National Park, Zimbabwe. Trends of other ungulates, including elephant Loxodonta africana, were examined simultaneously, because sable may be sensitive to forage and apparent competition and to high elephant densities. Sable densities declined in the whole region, very likely because of adverse rainfall conditions. Densities were constantly higher in the hunting areas and forestry lands than in the national park. Interestingly, elephant densities showed the opposite, with higher densities in the national park than in the adjacent areas. Whether these results reflect a negative effect of high elephant numbers on sable must still be tested directly. Likewise, while habitat characteristics and lion predation did not appear responsible for the higher sable densities outside the national park, they could not be discounted as an influence on the differing sable densities in different land-use areas. It is clear, however, that high protection status is not always sufficient to ensure adequate conservation of flagship species. We therefore call for further investigations of ecological interactions within protected areas. [ABSTRACT FROM AUTHOR]

Confined to a small region in central Angola, the giant sable antelope ( Hippotragus niger variani) experienced a dramatic decline in numbers and is currently one of the most endangered African mammals. In spite of its iconic status, conservation efforts have been hindered by unsustainable hunting and lack of adequate tools to promote its recovery. In this work, we developed a set of 57 microsatellites specific for the giant sable, which revealed depleted levels of genetic diversity and an allele frequency spectrum consistent with a recent evolutionary history characterized by severe population crashes. In contrast, the high number of private alleles exhibited by other H. niger populations from Zimbabwe and Tanzania may suggest the occurrence of reduced levels of gene flow among sable populations. Our microsatellite panel was successfully tested on the roan antelope, Hippotragus equinus, and will prove highly applicable on the characterization of different Hippotragus populations, but in particular for the conservation of the Angolan giant sable antelope. [ABSTRACT FROM AUTHOR]

The giant sable antelope is one of the most endangered African bovids. Populations of this iconic animal, the national symbol of Angola, were recently rediscovered, after many decades of presumed extinction. Even so, their numbers are scarce and hence conservation plans are essential. However, fundamental information such as its taxonomic position, time of divergence and degree of genetic variation are still lacking. Here, we used a museum preserved horn as a source of DNA to describe, for the first time, the complete mitochondrial genome of the giant sable antelope, and provide insights into its evolutionary history. Reads generated by shotgun sequencing were mapped against the mitochondrial genome of common sable antelope and the nuclear genomes of cow and sheep. Phylogenetic reconstruction and divergence time estimate give support to the monophyly of the giant sable and a maximum divergence time of 170 thousand years to the closest subspecies. About 7% of the nuclear genome was mapped against the reference. The genetic resources reported here are now available for future work in the field of conservation genetics and phylogeny, in this and related species. [ABSTRACT FROM AUTHOR]

This survey of ixodid ticks was the first to compare the species composition and population dynamics of free-living ticks in intensive, sable antelope breeding enclosures, now commonplace in commercial wildlife ranching in South Africa, with those of multi-herbivore enclosures. The species composition, abundance and seasonal abundance of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelope (Hippotragus niger), on which strategic tick control is practised, were compared with those of ticks in a multi-species herbivore enclosure surrounding the breeding enclosures in which no tick control is practised. A total of eight ixodid tick species were collected by drag-sampling the woodland and grassland habitats in each enclosure type monthly from July 2011 to July 2013. Rhipicephalus decoloratus, a potential vector of fatal tick-borne disease in sable antelopes, was the most abundant, accounting for 65.4% of the total number of ticks collected in the sable enclosures, whilst representing only 25.4% of number of ticks collected in the multi-species herbivore enclosure. Rhipicephalus decoloratus and R. evertsi evertsi were more abundant than R. appendiculatus (both p < 0.05) and Amblyomma hebraeum (p < 0.001 and p < 0.01, respectively). Rhipicephalus decoloratus larvae were collected throughout the year, with peak collections in November 2012 and October to December 2013 in the sable enclosures; and in April/May 2012 and February/April 2013 in the multi-species herbivore enclosure. More R. decoloratus were recovered in the second year than in the first year in the grassland habitat of the sable enclosures (V = 7.0, p < 0.05) possibly as a result of acaricide resistance. The apparent temporal over-abundance of R. decoloratus in sable antelope breeding enclosures, in the face of strategic tick control, is of concern and requires further investigation. [ABSTRACT FROM AUTHOR]

In the Kruger National Park, sable antelope underwent a substantial decline in abundance after 1987. Our study investigated whether forage quality as reflected by faecal nutrient contents could be restricting population recovery. Faecal samples were collected from sable, zebra and buffalo in one study area and from sable only in a second study area with higher mean rainfall, during the dry seasons of two successive years. Faecal samples were analysed for nitrogen, phosphorus, sodium and crude fibre. Faecal nitrogen and phosphorus levels were similar for sable and buffalo and remained around or slightly above putative maintenance levels, but were higher than shown by nonruminant zebra. Faecal sodium levels were substantially lower for sable than for the other two grazers. In the wetter study area, faecal nitrogen levels for sable herds fell below the minimum maintenance level throughout the dry season in the drier year. Although faecal nutrient levels for sable appeared only marginally limiting under the conditions that prevailed during the study, malnutrition could have contributed to the population decline by sable during a persistently low-rainfall period. [ABSTRACT FROM AUTHOR]

Daily activity schedules and time budgets reveal how animals cope with changing environmental conditions in securing food and evading enemies. Theory suggests that animals in populations limited by food availability should be energy maximizers in their foraging time allocation, while those regulated by predation should minimize their mobile activity levels. We compared daily and seasonal variation in activity states among three species of grazing ungulates coexisting in the same region of Kruger National Park, South Africa, and for one of these species between regions differing in rainfall. These grazers differed in body size and digestive physiology, potentially affecting their activity patterns. Hourly movement rates recorded by GPS telemetry were partitioned among activity states by applying independent mixture models. All three species showed activity peaks during the early morning and late afternoon, while resting prevailed pre-dawn as well as through midday. African buffalo showed the strongest diel variation in activity and greatest depression of midday activity, consistent with their large body size. Buffalo maintained similar levels of activity through the day and night, while zebra and sable antelope showed higher levels of diurnal than nocturnal activity. During the late dry season, zebra and coexisting sable, but not buffalo, showed elevated foraging and total mobile activity. Zebra devoted more time to foraging than both ruminants, consistent with greater food intake requirements for hindgut digestion. Sable antelope inhabiting the region with higher rainfall showed similar activity levels to the sable herd in the drier area, but slower rates of movement while foraging and travelling and less elevation in foraging time towards the end of the dry season. Observed patterns indicated subtly changing interplay among different constraints bearing on activity patterns over the diel and seasonal cycles, especially those related to digestive physiology. Simplistic concepts of energy maximization or time minimization were not supported. [ABSTRACT FROM AUTHOR]

Animals selectively utilize their environments within a hierarchical framework. Our study addressed how the home ranges of sable antelope selectively incorporated the landscape and habitat types available to them. It was conducted in a region of northern Botswana where the sable population was expected to be thriving, in contrast to their threatened status in the wild in South Africa. The movements and habitat use of three neighbouring sable herds were recorded by global positioning system ( GPS) telemetry during parts of the seasonal cycle in a region adjoining the seasonally flooded Okavango Delta. Total home range extents covered by these herds were larger than those found for sable in other areas, and local population densities, taking into account the herd sizes, were accordingly lower than in these other areas. Access to surface water appeared to be the main limitation on seasonal home range occupation. Almost all of the local vegetation types were utilized, but sable herds generally favoured dryland grassland during the dry season and floodplain grassland during the wet season, contrary to what we had expected. Hence, it appeared that local home range occupation and habitat use by the three sable antelope herds could be influenced more by interactions with potential competitors and predators than by intrinsic habitat suitability. [ABSTRACT FROM AUTHOR]

From remotely sensed woody cover, we tested whether sables under hunting pressure preferred closed woodland habitats and whether those not under hunting preferred more open woodland habitats. We applied a two factorial logistic regression analysis to model the probability of occurrence of sable antelope in hunted and non-hunted areas of northwest Zimbabwe as a function of vegetation cover density (estimated by a normalized difference vegetation index (NDVI)). We validated the results by high-spatial resolution imagery derived tree canopy area. We subsequently compared the predictions from the two models in order to compare sable cover selection between hunted and non-hunted areas. Our results suggest that hunted sables are likely to select closed woodland, while non-hunted ones would prefer more open woodland habitats. We also established a significant positive relationship between NDVI and tree canopy cover, thus emphasizing the importance of remote sensing in studies that measure the impact of hunting on habitat selection of targeted species. [ABSTRACT FROM AUTHOR]

Trophy hunting in ungulates may favour individuals with smaller horns. A decrease in horn/antler size may jeopardize the conservation potential of hunting areas, which would be a major concern in Africa where hunting zones represent over half of the total area of protected lands. We investigated horn length trends of harvested male impalas Aepyceros melampus, greater kudus Tragelaphus strepsiceros and sable antelopes Hippotragus niger, from 1974 to 2008 in Matetsi Safari Area, Zimbabwe. Horn length declined by 4% in impalas, partly because male harvest age decreased. In greater kudus, surprisingly, horn length increased by 14%, while mean age of harvested male greater kudus increased during the study period. Reduced hunting pressure on this species during the study may have allowed males to live longer and to grow longer horns before being harvested. Horn length declined by 6% in sable antelopes, independent of age, suggesting that trophy hunting selected male sable antelopes with smaller horns through time, provided that horn length is heritable. Hunting pressure and trophy value were higher for sable antelopes than for impalas and greater kudus. Accordingly, the decline of horn length in this species was more pronounced. More valuable trophy species, such as sable antelopes, require special attention because they may be exposed to higher hunting pressure, and are therefore more likely to experience a decrease in horn size. [ABSTRACT FROM AUTHOR]

Animals that are relatively rare in local species assemblages are commonly assumed to be narrowly selective in their habitat or dietary requirements, with the latter generally assessed in terms of the range of food types consumed. We investigated whether a narrow dietary range might help explain the restricted distribution and low local densities attained by sable antelope Hippotragus niger compared with other grazing ungulates. Selection by sable antelope for grass species, its relation to species availability and the resulting evenness of the diet were compared with these measures for zebra Equus quagga, which are assumed to be generalist feeders owing to their hindgut fermentation system, under dry season conditions when food was most limiting. Both grazers exhibited a clear distinction between highly favoured and infrequently accepted or rejected grass species in the same region, and both favoured mostly the same common grass species, but sable showed greater acceptance of several less common grass species than did zebra. Distinctions were evident among individual sable herds in favoured grass species, dependent on local availability. Dietary evenness was similar for sable and zebra herds overall, although seasonal trends differed depending on whether animals concentrated their diet more narrowly on a few grass species or broadened it during more extremely dry conditions. Hence, although sable were more narrowly selective for green leaf content than zebra, the dietary acceptance range of these two grazers at grass species level did not differ fundamentally. In particular, sable readily consumed tall grass species rated as having low to moderate forage value. This dietary tolerance enables sable antelope to occupy savannah woodlands associated with relatively infertile soils where the risk of predation is reduced due to the relatively low abundance of other prey. Accordingly, the causes of local rarity may lie in the restricted availability of food in the places to which these species are restricted by other factors. [ABSTRACT FROM AUTHOR]

The giant sable antelope ( Hippotragus niger variani) is a critically endangered subspecies with a range restricted to a small area in the Angolan plateau. It is known to display geophagic behaviour, eating the soil of some Macrotermes termitaria. The aim of this study was to understand the importance of this behaviour for the giant sable and other ungulates sharing its range. We identified termite mounds used for geophagy based on local information confirmed by self-triggering cameras. We collected and analysed soil samples of seven termitaria consumed by ungulates, the adjacent topsoil 50 m away from each, and seven control nonconsumed termitaria. Consumed termite mounds were richer in minerals than control mounds, and both were richer than the surrounding topsoil. Sodium levels showed the greatest contrasts and were about 20 times more abundant in consumed termitaria than in controls. The amount of sodium in background soil was extremely low (9.3 ppm), suggesting that this mineral is a limiting nutrient in the range of the giant sable. These results indicate that the observed geophagic habits may be driven by a need to compensate for a sodium deficiency. This situation should be considered in the planning of the species' conservation. [ABSTRACT FROM AUTHOR]

The sable antelope (Hippotragus niger) has been kept in the Prague Zoo since the year 1970. In total 110 young were born there. Fifty individuals were exported to different zoos. Births were recorded all year round with a maximum at the beginning of October, and another peak in March-May. In all the litters, only a single offspring was born. The ratio of females versus males was 52:48. More than 27% of the juveniles did not live longer than half a year. Sexual maturity was reached at the age of two years in young males, and at the age of 1.5 years (exceptionally earlier) in young females, respectively. The gestation period ranged from 8 months and 27 days to 9 months and 6 days. The shortest interval between births was 9 months and 2 days. The most fertile females gave birth to fourteen juveniles. The oldest breeding hind delivered at the age of 14 years. The oldest individual (female) was culled at the age of 14.5 years. Altogether 48 skulls of the Sable antelope were deposited in the collection of the National Museum, Prague. [ABSTRACT FROM AUTHOR]

Sable antelope numbers in the Kruger National Park have declined substantially since the mid-1980s and have shown little recovery despite improved rainfall conditions. We used aerial survey records to investigate how changes in herd numbers, herd sizes, calf proportions and consequent changes in the distribution range of breeding herds contributed to this situation. Both herd sizes and herd numbers decreased in the drier northern half of the park, coupled with low calf proportions, especially during and following a severe drought, while declines in these measures became evident later in the wetter southern half. Herd extirpations led to a 25% contraction in the local distribution range of sable antelope, although some of these herds had only become established during the high rainfall period in the late 1970s. Local population trends were not related to increases in zebra numbers potentially attracting more predators. Compensatory density dependence in the population growth rate was no longer evident after 1986 during the period of the population decline. The population trajectory modelled from rainfall relationships indicated that the depressed population growth rate relative to rainfall apparent after 1986 has persisted, implicating either enduring habitat degradation or continuing high predation pressure. The pattern of the population decline and subsequent lack of recovery raises the possibility that an Allee effect could be operating, mediated through the consequences of reduced herd sizes for exposure to predation. Our findings suggest how delays in responding to declining population numbers could prejudice population recovery well before the overall population size drops to levels threatening population viability. [ABSTRACT FROM AUTHOR]

Resource partitioning among the ungulate species occupying African savanna ecosystems has been well documented in relation to food resources and habitat features, but few studies have addressed how distinctions in surface water dependency contribute to coexistence. During the dry season surface water becomes restricted to a few perennial sources, while the food resources remaining at this time are also most limited in quantity, especially near water where animals congregate to drink. We compared the movement patterns to and from water of sable antelope Hippotragus niger and zebra Equus quagga herds in Kruger National Park (KNP), South Africa. Owing to distinctions in their digestive systems, we expected sable to drink less frequently than zebra, allowing sable to occupy regions further from surface water than zebra. Sable travelled to water at 2-4-day intervals, versus 1-2-day intervals for zebra. However, sable travelled c. 25% greater distances to water due to the location of their late dry season home ranges relative to perennial water sources; zebra home ranges were generally closer to water sources. Travelling 10-15 km to and from water substantially reduced time spent foraging and resting by both species on days when animals drank. Longer intervals between travel to water by the sable antelope herd enabled it to occupy regions of the landscape further from water than those heavily exploited by the more common grazers during the critical dry season months. By avoiding concentrations of other grazers, the sable also probably gained a reduction in predation risk, balancing the substantial costs in terms of time and energy associated with travel to water. Thereby the distinctions in water dependency of this relatively rare grazer facilitated its coexistence alongside more abundant grazers in the KNP. [ABSTRACT FROM AUTHOR]

Introductions of sable antelope (Hippotragus niger) can be difficult due to the potential ensuing aggression compounded by their large horns. The goal was to use hormonal assays and behavioral analyses to evaluate the success of an introduction of 2 adult females at Lincoln Park Zoo. The objectives were to (a) document behavioral and hormonal changes in 2 female sable antelope during the introduction, (b) compare fecal glucocorticoid metabolites (FGM) in each individual during the introduction stages, (c) measure fecal androgen metabolites (FAM) during introduction and compare with dominance rank and observed aggression, and (d) monitor estrous cycle synchronization. Results demonstrate that FGM were higher before than during and after the introduction. Behavioral observations indicated limited aggression between females, although the keeper survey results revealed that the new female was more dominant and had higher mean FGM and FAM than the resident. Both sable antelope were reproductively active throughout the year. Results indicate that fecal hormone analysis can provide zoo management with valuable information to minimize the risk of aggression, injury, and stress during introductions of nonhuman animals. [ABSTRACT FROM AUTHOR]

Skin lesions associated with papillomaviruses have been reported in many animal species and man. Bovine papillomavirus (BVP) affects mainly the epidermis, but also the dermis in several species including bovine, the best-known example being equine sarcoid, which is associated with BVP types 1 and 2. This publication describes and illustrates the macroscopic and histological appearance of BPV-associated papillomatous, fibropapillomatous or sarcoid-like lesions in Cape mountain zebra (Equus zebra zebra) from the Gariep Dam Nature Reserve, 2 giraffes (Giraffa camelopardalis) from the Kruger National Park, ar.d a sable antelope (Hippotragus niger) from the Kimberley area of South Africa. An African buffalo (Syncerus caffer) cow from Kruger National Park also had papillomatous lesions but molecular characterisation of lesional virus was not done. Immunohistochemical staining using polyclonal rabbit antiserum to chemically disrupted BPV-1, which cross-reacts with the Li capsid of most known papillomaviruses, was positive in cells of the stratum granulosum of lesions in Giraffe 1, the sable and the buffalo and negative in those of the zebra and Giraffe 2. Fibropapillomatous and sarcoid-like lesions from an adult bovine were used as positive control for the immunohistochemistry and are described and the immunohistochemistry illustrated for comparison. Macroscopically, both adult female giraffe had severely thickened multifocal to coalescing nodular and occasionally ulcerated lesions of the head, neck and trunk with local poorly-circumscribed invasion into the subcutis. Necropsy performed on the 2nd giraffe revealed neither internal metastases nor serious underlying disease. Giraffe 1 had scattered, and Giraffe 2 numerous, large, anaplastic, at times indistinctly multinucleated dermal fibroblasts with bizarre nuclei within the sarcoid-like lesions, which were BPV-1 positive in Giraffe 1 and BPV-1 and -2 positive in Giraffe 2 by RT-PCR. The sable antelope presented with a solitary large lesion just proximal to the right hind hoof, which recurred after excision, and was BPV-1 positive by RT-PCR. Other wart-like growths were present elsewhere on the body. The Cape mountain zebra either succumbed from their massive lesions or were euthanased or removed from the herd because of them. The lesions were BPV-1 and/or -2 positive by RT-PCR. The buffalo lesions were wart-like papillomatous projections in the inguinal and udder region. Stratum granulosum cells that stained immunohistochemically positive in the various species appeared koiocyte-like, as described in human papillomaviral lesions. [ABSTRACT FROM AUTHOR]

Papillomavirus was detected electron microscopically in cutaneous fibropapillomas of a giraffe (Giraffa camelopardalis) and a sable antelope (Hippotragus niger). The virus particles measured 45 nm in diameter. Histopathologically, the lesions showed bistopathological features similar to those of equine sarcoid as well as positive immunoperoxidase-staining of tissue sections for papifiomavirus antigen. Polymerase chain reaction (PCR) detected bovine papillomavirus (BPV) DNA. Bovine papillomavirus-1 was characterised by real-time PCR in the sable and giraffe, and cloning and sequencing of the PCR product revealed a similarity to BPV-1. As in the 1st giraffe, the lesions from a 2nd giraffe revealed locally malignant pleomorphism, possibly indicating the lesional end-point of papilloma infection. Neither virus particles nor positively staining papillomavirus antigen could be demonstrated in the 2nd giraffe but papillomavirus DNA was detected by real-time PCR which corresponded with BPV-1 and BPV-2. [ABSTRACT FROM AUTHOR]

Burning is commonly used in savannas to stimulate grass regrowth for grazing ungulates. We recorded the relative use of burns occurring at different stages in the seasonal cycle, as well as in different regions of the landscape by two herds of sable. We also recorded behavioural measures of foraging efficiency and faecal nutrient contents as an indication of nutrient gains. Sable consistently concentrated their grazing on burned areas provided there was sufficient green regrowth during the dry season. In these circumstances they grazed for longer per feeding station, showed a slower step rate while foraging, and shorter between-patch moves, and a higher probability of encountering acceptable food per step taken while foraging than on unburnt areas. In the year when only a burn with insufficient regrowth was available, sable continued to forage in the area that had been burned during the previous year. Faecal crude protein was substantially higher at the end of the dry season in the year when burned areas were utilized. Accordingly early dry season fires can be important in helping sable bridge the nutritional limitations posed by the dry season, provided sufficient soil moisture remains to promote adequate grass regrowth. [ABSTRACT FROM AUTHOR]

The giant sable (Hippotragus niger variani) is one of Africa's most spectacular large antelope. Years of civil unrest in Angola, a highly localized distribution and interbreeding with its congener the roan antelope (H. equinus) has led to this subspecies being considered as critically endangered. Sable antelope occurring -600 km to the east in western Zambia superficially resemble giant sable in phenotype, prompting speculation in the popular media that the distribution of giant sable may be larger than currently documented. Our aim here was to investigate the evolutionary placement of western Zambian sable using mitochondrial DNA control region data. Phylogenetic analyses (maximum likelihood and Bayesian analyses) supported the monophyly of H. n. variani(Bayesian posterior probability of >0.95, bootstrap support >80%) and nested the western Zambian sable within H. n. niger. This finding was supported by an analysis of molecular variance that discretely grouped western Zambian sable from giant sable (ΦST = 0.645, P = 0.001). Significant genetic structure was also found across the range of H. n. nigeras indicated by our phylogenetic analyses and analysis of molecular variance (ΦST = 0.418, P = 0.001). We conclude that although the western Zambian sable antelope and those of H. n. variani resemble one another in morphology, particularly with respect to facial markings, significant genetic differences underpin these two evolutionary lineages. Our findings hold implications for the conservation of sable and highlight the need for active management intervention. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of putting down a giant sable antelope in Angola with biologist Pedro Vaz Pinto.

Concern about the habitat requirements of sable antelope (Hippotragus niger) has increased due to population declines shown in some protected areas. Our study was prompted by the lack of initial increase by the sable antelope introduced into the Pilanesberg Game Reserve in North West Province, South Africa; 67 animals released between 1979 and 1983 had only grown to approximately 70 animals by 1988. We recorded forage selection by sable antelope within the context of the landscape units favoured in different seasons. Chrysopogon serrulatus, Panicum maximum, Heteropogon contortus, and Themeda triandra contributed most to the diet of sable antelope. Faecal crude protein content did not drop below 6.6% of dry matter during the dry season, with use of burnt grassland by sable contributing to an elevation in faecal protein levels at the beginning of the wet season. The sable population had increased to 127 animals by 1991, suggesting that the earlier lack of population growth had been due to below-average rainfall, lack of burns providing green regrowth during the dry season, or a delay in learning to exploit available forage resources efficiently. [ABSTRACT FROM AUTHOR]

GPS collars linked to the GSM (cellular phone) network open new opportunities for documenting the responses of animals to changing environmental conditions.These collars supply sequential location records according to a pre-set schedule, without any interference by an observer with animal movements. We report findings from a preliminary analysis of data from collars placed on two adjoining herds of sable antelope (Hippotragus niger) in the central region of the Kruger National Park. These collars functioned for 11.5 months and 15 months, respectively, routinely supplying GPS positions of both herds at 12 h (or shorter) intervals. From these data we derived diel displacement distances between locations 24 h apart, as well as diurnal and nocturnal (12 h) displacements. Annual home ranges of these herds covered 118 km² and 65 km², respectively. Diel displacements did not show any consistent distinction between short movements within foraging areas and long movements between foraging areas. Diel displacements increased over the course of the dry season, largely as a result of journeys to water every 3-4 days. Animals moved relatively more nocturnally during the hot months of the dry season than at other times of the year. Longer movements suggested higher energy expenditures and greater risks of predation in the late dry season. [ABSTRACT FROM AUTHOR]

GPS/GSM collars were fitted to females in two sable antelope herds occupying adjoining home ranges in the Kruger National Park in order to establish their movement responses to seasonally changing resource availability. This investigation formed part of a larger study aimed at identifying the factors responsible for the substantial population declines by this and other rarer antelope species in the protected area. To indicate responses to stressful periods during the seasonal cycle, we used the following measures: (a) proportion of locations outside the home range core, (b) displacement distances from day to day in foraging locations, and (c) extent of movement at night versus during daylight. Movements beyond the home range core were affected by excursions to water as well as foraging locations. When food and water availability became restricted during the dry season, one herd extended its range well beyond the core region favored during the wet season, while the other herd concentrated its space use more tightly within the core region, except during excursions to water. Journeys to water also affected the patterns shown by diel (24 h) displacements calculated between morning versus evening foraging locations. Diel displacement distances between evening locations were minimal when both food and water were plentifully available, and were greatest for one herd during the late dry season, but for the other herd when rainfall deficits occurred during a wet season month. Nocturnal movement showed a peak in the transition period between the dry and wet season when both resources were restricted and prevailing temperatures high. Hence, while these measures did indicate periods when resources became restricted, results revealed some of the complexities due to interactions between food and water availability. Findings also emphasised the limited extent of the landscape upon which sable depended for their resource requirements. [ABSTRACT FROM AUTHOR]

Abstract Empirical investigations of intraspecific outbreeding and subsequent introgressive hybridization in natural populations are rare, particularly among conspecific populations of large mammals. Using mitochondrial DNA data [partial control region (496 basepairs — bp) and cytochrome b gene (343 bp) sequences analysed from 95 individuals representing 17 sampling locations scattered through the African miombo (Brachystegia ) woodland ecosystem] and phylogeographical statistical procedures (gene genealogy, nested cladistic and admixture proportion analyses), we (i) give a detailed dissection of the geographical genetic structure of Hippotragus niger ; (ii) infer the processes and events potentially involved in the population history; and (iii) trace extensive introgressive hybridization in the species. The present-day sable antelope population shows a tripartite pattern of genetic subdivision representing West Tanzanian, Kenya/East Tanzanian and Southern Africa locations. Nested clade analysis revealed that past allopatric fragmentation, caused probably by habitat discontinuities associated with the East African Rift Valley system, together with intermediary episodic long-distance colonization and restricted, recurrent gene flow have played an predominant role in shaping the extent of maternal genetic diversity (10.4%) and population structure. An extensive (average rate of admixture = 20.0%), but geographically circumscribed and unidirectional hybridization event in the past was inferred, resulting in an extreme (the highest discovered so far in mammals) intraspecific difference of 18.2% among morphologically monotypic sable antelopes from West Tanzania. The results are used to provide an evolutionary framework within which taxonomic implications and conservation decisions can be evaluated. [ABSTRACT FROM AUTHOR]

Read the Feature Paper: Does trophy hunting matter to long‐term population trends in African herbivores of different dietary guilds?; other Commentaries on this paper: Monitoring required for effective sustainable use of wildlife and the Response from the authors: The assessment of the role of trophy hunting in wildlife conservation [ABSTRACT FROM AUTHOR]

Attempts to study the role of female flehmen behavior in maintaining reproductive synchrony in female sable antelope, Hippotragus niger. Methods; Results; Discussion.

Investigates the karyotype of the sable antelope by RBG- and GTG-banding techniques. Materials and methods; Results and discussion.

Presents a study which looked at the relationship between timing of birth in relation to the other births in the social group, and the subsequent rate of spatial integration into the herd in infant sable antelope, Hippotragus niger. Details on birth synchrony; In-depth look at a behavioral observation; Temporal distribution of births; Results of the study.