Slender Mongoose Research Articles

Comparison of the effectiveness and efficiency of the grid and link search methods to recover scattered skeletal remains

The grid and link search methods are used to recover scattered skeletal remains. Neither have not been compared robustly and clear guidelines for the link method have not been sufficiently developed. The study aimed to compare the effectiveness and efficiency of both methods and propose guidelines for the link method. The scattering patterns of two scavengers of forensic relevance—slender mongooses (Galerella sanguinea) and black-backed jackals (Canis mesomelas)—were recreated using four pig skeletons (Sus scrofa domesticus). Two groups (n = 6 each) were assigned a different method to recover the scattered remains. The length of the search and when each bone was located for each scatter pattern was recorded for each group and scatter pattern. A Likert scale questionnaire assessed participants’ perceptions of their assigned method. A paired t-test (p = 0.005) compared the efficiency of each method and the questionnaire answers. Both methods were effective, recovering 100% of all remains. The link method was more efficient for both scatter patterns, despite there being no statistical significance (jackal: p = 0.089; mongoose: p = 0.464). Participants indicated favorable views for both methods; however, the link method scored significantly more favorably (p = 0.01) for efficiency. Specific guidelines were developed for the use of the link method. The link method is suggested for the recovery of scattered remains in forensic contexts, especially when the scavenger, its behavior, and scattering pattern is known or suspected.

An occupancy analysis of the factors affecting the presence of carnivores at the national park‐human community interface in Rwanda

AbstractPeople, livestock and carnivores are constantly interacting especially at the interface between community and protected areas. The carnivore guild category in Volcanoes National Park is important, and if well studied, could lead to additional research opportunities for improved wildlife management. We used single season occupancy models with multi‐species data, to understand the factors affecting species occurrence, detection and distribution among native carnivores of Volcanoes National Park while accounting for imperfect detection and the effects of site variables on the observed trends. Our findings showed that six native carnivores use the park edge, where the side‐striped jackal (Canis adustus) and serval (Leptailurus serval) are the most widespread with ψ = 0.904 (SE 0.051) and ψ = 0.415 (SE 0.086), respectively, followed by African golden cat (Caracal aurata) with ψ = 0.198 (SE 0.066), while the servaline genet (Genetta servalina), slender mongoose (Herpestes sanguineus) and spotted hyaena (Crocuta Crocuta) have very low probability of occupancy with ψ = 0.087 (SE 0.045), ψ = 0.044 (SE 0.032) and ψ = 0.022 (SE 0.022) respectively. In addition, there is high occurrence of feral dogs and human presence in the park edge. Overall, the occupancy of native carnivores increases as distance from settlements increase (β = 0.559 [SE 0.195]) except for hyaena and mongoose which showed a decrease in occupancy as distance to settlements increased. In general, native carnivores preferred sites located close to pasture areas, compared to areas used for agriculture and agroforestry. High overlapping activity between native carnivores and other wildlife varied greatly between species. This study provides the baseline information for the understanding of native carnivores using the park edge and insights on their interactions with other wildlife, livestock and human activities at the interface between the park and local communities. The co‐occurrence of livestock, feral dogs and humans, and native wildlife is a challenge for both wildlife conservation inside the protected area and local communities who might be negatively affected in different ways including interspecific competition, disease exposure and increased conflicts. We anticipate that some of the current livestock keeping are hindered by the challenges of having native carnivores dwelling along the park edge and community interface.

Identifying forensically relevant urban scavengers in Johannesburg, South Africa

Unidentified human remains are frequently recovered in urban environments in South Africa, which undergo forensic (medico-legal) investigations. These remains often exhibit animal scavenging modifications and are frequently scattered by animals. This impacts the collection and forensic analysis of the remains. This study aimed to identify scavenging animals present in two urban environments in Johannesburg, South Africa, and describe their scavenging and scattering behaviours. Six pig carcasses (Sus scrofa domesticus) (30–80 kg) were placed in a veldt in Johannesburg and in an abandoned building complex. Motion-activated cameras recorded the scavenging activities. Scavenger species were identified and their behaviours, scattering pattern, and scavenging bone modifications were described. Slender mongooses (Galerella sanguinea) were the most prolific veldt scavengers. They scattered remains to a maximum distance of 10.5 m in two directions: north and southeast. These mongooses scavenged during the advanced and dry decomposition stages. Gnawing on the angle of the mandible - with multiple parallel scores on the flat surfaces and the angle margin having a stepped appearance - may be a distinguishing scavenging modification feature of the slender mongoose. Hadeda ibis (Bostrychia hagedash) were the only scavengers recorded scavenging on the intestines of a pig carcass in the abandoned building complex. They favoured colonizing insects and created multiple, large holes in the skin and removed the lips to access the insects. The described scavenging behaviours will assist in the reconstruction of postmortem events in forensic cases and the location and collection of scattered remains in Southern Africa.

Small mammal species diversity and distribution in the Selous ecosystem, Tanzania

Threats to ecosystems are ever increasing from different drivers mostly being linked to anthropogenic activities. This has brought about various measures to restore/protect the wildlife in these areas. Considering the background of most protected areas in East Africa, small mammals have been given least attention, compared with large mammals, although they play a fundamental role in maintaining ecosystem health. It is therefore necessary to understand how small mammals are distributed in any given ecosystem as a baseline information to enable holistic and informed management. We investigated the diversity and distribution of small mammals in the Selous ecosystem, Tanzania. Two methods were used; Capture Mark Recapture (CMR) using grids of 70 m x 70 m and random placement of havahart traps in the selected habitats. Between July 2018 and June 2020, a total of 887 individuals belonging to 20 species were captured in 28 224 trap nights with 3% trap success. The small mammal species captured consisted of rodents (91.8%), Macroscelidea (3.9%), Carnivores (2.4%) Eulipotyphla (1.6%), and Primates (0.3%). Acomys ngurni (36%) and Aethomys chrysophilus (17%) were the most captured species, whereas Atilax paludinosus (0.23%), Helogale pervula (0.23%), Rattus rattus (0.23%) and Galerella sanguinea (0.11%) were the least contributing species. Acomys ngurui and Lemniscomys rosalia were the most distributed species occurring in all four habitats, whereas Cricetomys ansorgei, Rattus rattus, Mungos mungo and Genetta genetta had low occurrence. Grammomys selousi is reported for the first time in the northern part of the Rufiji River. Acomys ngurni abundance differed significantly (χ2 = 12, df = 3, p = 0.007) between the four habitats being higher in the seasonal riverine forest and across seasons (χ2 = 6, df = 2, p = 0.049), with more individuals occurring in the wet season. The Sable Forest habitat had the highest species diversity (H' = 2.065) and the lowest diversity (H' = 1.506) was recorded in perennial riverine forest/thickets. The highest species diversity (H' = 1.65) was recorded in the dry season and the lowest diversity in the wet season (H' = 1.445). Most small mammals were associated with seasonal riverine forest than other habitats. Overall, the results from this study show that, the park is rich in small mammal fauna. Therefore, considerations in updating the General Management Plan (GMP) and other plans to include the small mammals in the park management actions is recommended.

The Determinants of Mesocarnivore Activity Patterns in Highveld Grassland and Riparian Habitats

Despite the diversity of mesocarnivores and the broad geographic ranges of these species, our understanding of their behaviour and ecology at multi-species and community levels is limited. Our study was conducted between April and mid-July 2015 and used data collected over 105 days from 39 camera traps to quantify activity patterns of sympatric mesocarnivores in riparian and grassland habitats of Telperion Nature Reserve, South Africa. A total of 13 mesocarnivore species were detected within this relatively small (∼7350 ha) reserve. Sufficient records (≥10 records) were obtained for rusty-spotted genet (Genetta maculata), black-backed jackal (Canis mesomelas), otter species (African clawless otter, Aonyx capensis, and spotted-necked otter, Hydrictis maculicollis), serval (Leptailurus serval ), slender mongoose (Galerella sanguinea), yellow mongoose (Cynictis penicillata) and marsh mongoose (Atilax paludinosus). Generalized linear models were used to investigate whether species ID, temperature, vegetation characteristics or moon phase best predicted temporal activity. To assess which species had the highest potential for competitive interaction, we also quantified the coefficient of activity overlap. Our results show that species ID and temperature were the best predictors of mesocarnivore activity. Slender and yellow mongooses displayed the highest coefficient of activity overlap (0.90), followed by marsh mongoose and rusty-spotted genet (0.80), and serval and rusty-spotted genet (0.79). These species are likely to have the highest potential for competitive interactions, but preferences for different vegetation characteristics and variations in the estimated relative abundance may point to coexistence through spatial and fine-scale temporal partitioning. The other species exhibited lower coefficients of activity overlap with each other, suggesting they may coexist through temporal partitioning of resources.

Spatiotemporal co-occurrence and overlap of two sympatric mongoose species in an urban environment

Abstract Small carnivores are becoming increasingly common in urban areas. What has received less attention is whether and how resource partitioning among sympatric species in urban areas facilitates their coexistence. We examined the spatial, temporal and combined spatiotemporal occurrence and overlap of co-existing yellow mongoose Cynictis penicillata and slender mongoose Galerella sanguinea in an urban estate in South Africa. The reserve comprised two parts, an Eco-Estate where human residential and natural areas are interspersed and wildlife has greater contact with people, and a Nature Estate, where contact is reduced by palisade fencing between people and natural areas. Using photographic data from camera traps collected over 11 consecutive months, we found a moderate level of spatial overlap between the mongoose species. Differences between the species occurred at a finer habitat scale: yellow mongooses were more common in open habitats located near human residents whereas the slender mongooses were more common in covered areas further away from human residents. The detection probability of the yellow mongoose, however, was greater than that of the slender mongoose, and the occupancy probability of the slender mongoose was reduced in the presence of the yellow mongoose. Although both species demonstrated bimodal diurnal peaks in activity, they varied in their active periods, with temporal overlap being greater during colder than warmer months. No complete spatiotemporal overlap (occurrence in the same place at the same time/within a 10-min period) occurred. This may have been as a result of the difference in detection and occupancy probabilities of the two species. Resource availability (food), however, appears to influence the different habitat selection, space use, and activity patterns of yellow and slender mongoose in the study area. Therefore, we conclude that partitioning along the spatial and somewhat on the temporal dimensions aids in the coexistence of these mongoose species in an urban environment.

First videos of endemic Zanzibar Servaline Genet Genetta servalina archeri, African Palm Civet Nandinia binotata (Mammalia: Carnivora: Viverridae) and other small carnivores on Unguja Island, Tanzania

The faunal diversity of the densely populated island of Unguja, Zanzibar archipelago, Tanzania, includes several endemic mammals. Camera-trapping in Jozani-Chwaka Bay National Park and Kiwengwa–Pongwe Forest Reserve in September 2017 captured the first video footage of the Zanzibar Servaline Genet Genetta servalina archeri, an endemic subspecies first formally described in 1998. Other native small carnivores were also recorded on video for the first time during this survey, including the African Palm Civet Nandinia binotata, which was first documented in print as present in Unguja in 2004. Also camera-trapped in 2017 were the Zanzibar Slender Mongoose Herpestes sanguineus rufescens and the Zanzibar Bushy-tailed Mongoose Bdeogale crassicauda tenuis. Follow-up camera-trapping in Jozani-Chwaka Bay National Park in August 2018 captured additional video of the Zanzibar Servaline Genet and the African Palm Civet. No images were obtained of the African Civet Civettictis civetta, or of the two introduced species—the Banded Mongoose Mungos mungo and the Small Indian Civet Viverricula indica—in either year. As the remaining natural habitat in Zanzibar shrinks in size and becomes fragmented, it is increasingly urgent to document the archipelago’s carnivores and other fauna, so that sound conservation measures can be implemented.

Social organization of a solitary carnivore: spatial behaviour, interactions and relatedness in the slender mongoose.

The majority of carnivore species are described as solitary, but little is known about their social organization and interactions with conspecifics. We investigated the spatial organization and social interactions as well as relatedness of slender mongooses (Galerella sanguinea) living in the southern Kalahari. This is a little studied small carnivore previously described as solitary with anecdotal evidence for male associations. In our study population, mongooses arranged in spatial groups consisting of one to three males and up to four females. Male ranges, based on sleeping sites, were large and overlapping, encompassing the smaller and more exclusive female ranges. Spatial groups could be distinguished by their behaviour, communal denning and home range. Within spatial groups animals communally denned in up to 33% of nights, mainly during winter months, presumably to gain thermoregulatory benefits. Associations of related males gained reproductive benefits likely through increased territorial and female defence. Our study supports slender mongooses to be better described as solitary foragers living in a complex system of spatial groups with amicable social interactions between specific individuals. We suggest that the recognition of underlying ‘hidden' complexities in these apparently ‘solitary' organizations needs to be accounted for when investigating group living and social behaviour.

Dietary overlap of two sympatric African mongoose species in an urban environment

Abstract Urbanisation creates challenges and opportunities for wildlife. Globally, small carnivores have colonised urban spaces, but we do not know whether or how sympatric carnivores partition resources in order to co-exist. We studied the diet and degree of dietary overlap of two sympatric herpestid mongooses – yellow, Cynictis penicillata, and slender, Galerella sanguinea mongoose – in a small urban nature area in South Africa. The composition of 2600 yellow and 2000 slender mongoose scats was sampled over a year in an Eco-Estate, where wildlife have contact with humans, and a Nature Estate, where contact is reduced. We analysed the frequency of occurrence of invertebrates, mammals, birds, plants and anthropogenic items in scats. Invertebrates and mammals were most abundant for both species in the Nature Estate and for slender mongoose in the Eco-Estate, while anthropogenic items were more prevalent in yellow mongoose scats in the Eco-Estate. Both species included anthropogenic items in their diet in the Eco-Estate only. Scat components varied seasonally. In summer, invertebrates were more abundant in scats of both species, yet during the colder months, invertebrates decreased and vertebrates (more so in the slender mongoose) and anthropogenic items (more so in the yellow mongoose) increased. Dietary overlap was greatest in summer and lowest in winter. Nonetheless, the specialised slender mongoose diet and a generalist yellow mongoose diet potentially facilitates their co-existence.

Establishing Bayesian priors for natural mortality rate in carnivore populations

ABSTRACTIn managed carnivore populations, natural mortality rate (d) is difficult to estimate directly, and context‐specific data are typically weakly informative about it. Nevertheless, natural mortality is potentially an important component of total mortality, particularly if additive to harvest or culling mortality. The natural mortality rate exhibits allometric or life‐history relationships that are invariant across diverse taxonomic groups, and it is valuable to derive estimates on this basis to serve as priors in later Bayesian models, steering parameter uncertainty towards biologically plausible values, and leading to more reliable model predictions and improved management recommendations. We used Bayesian hierarchical modeling and data from the literature to establish informative priors for instantaneous d as predictions scaled from body mass or maximum age. Posterior mean estimates of the scaling parameters of these models were −0.27 (body mass) and −1.07 (maximum age), respectively, conforming to expected values of −0.25 and −1.00. Direct estimates of d from published studies of coyotes (Canis latrans) in southern Texas, fisher (Pekania pennanti) in Sierra Nevada, and slender mongoose (Galerella sanguinea) in the Kalahari Desert were within the credible intervals of predictions for d using both models. We also compared survivorship curves based on model predictions with observed survivorship of red fox (Vulpes vulpes) from a variety of studies in Britain, among which intensity of culling varied markedly. Across all species, there was better support for the d prediction from maximum age, than from body mass. We thus recommend use of maximum age data to establish informative priors for d where possible. Posterior median predictions of d from maximum age were within 0.01–0.14/year of the direct estimates, whereas the differences between direct estimates and predictions from body mass were 0.04–0.27/year. Sensitivity analysis showed trivial effects of between‐sex differences in body mass, and age‐specific mortality, on predictions of d. Differences between body mass and maximum age model predictions were attributed to the relative importance of intrinsic and extrinsic mortality factors in the 2 approaches (i.e., maximum age predictions allowed for extrinsic factors to affect predicted mortality). © 2018 The Wildlife Society.

Identity of Haemaphysalis (Rhipistoma) muhsamae Santos Dias, 1954 (Acari: Ixodidae) and H. (R.) subterra Hoogstraal, El Kammah & Camicas, 1992, parasites of carnivores and rodents in eastern and southern Africa.

Haemaphysalis (Rhipistoma) muhsamae Santos Dias, 1954 (Acari: Ixodidae) and H. (R.) subterra Hoogstraal, El Kammah & Camicas, 1992, are redescribed based on males and females. Adults of H. muhsamae were mostly collected from various mongooses (Carnivora: Herpestidae) but also from the striped polecat, Ictonyx striatus (Perry) (Carnivora: Mustelidae), serval, Leptailurus serval (Schreber) (Carnivora: Felidae), red veld rat, Aethomys chrysophilus (de Winton) and Selinda veld rat, Aethomys silindensis Roberts (Rodentia: Muridae) in Botswana, Kenya, Mozambique, South Africa, Tanzania and Zimbabwe. Adults of H. subterra were mostly found on various species of African mole rats, Tachyoryctes spp. (Rodentia: Spalacidae) but also on striped polecat, I. striatus and slender mongoose, Galerella sanguinea (Rüppell) (Carnivora: Herpestidae) in Ethiopia and Kenya. Males and females of both species can be differentiated from each other and other H. spinulosa-like ticks by their size, pattern of punctations on conscutum/scutum, shape of genital structures, shape and size of posterodorsal and posteroventral spurs on palpal segment II, hypostome dentition, and shape and size of spurs on coxae. Taxonomic issues of both species and those related to the identity of H. (R.) spinulosa Neumann, 1906 are discussed and a neotype of H. muhsamae has been designated.

Food choice and feeding on carrion in two African mongoose species in an urban environment

Urbanisation negatively affects many species, yet small carnivores may flourish in urban spaces because of accessible resources and a reduction of predators. Food choices of urban carnivores might be influenced by the availability and abundance of anthropogenic food resources and the co-existence of competing species. We studied the food selection and feeding on carrion of the yellow mongoose (Cynictis penicillata) and slender mongoose (Galerella sanguinea) in a small urban reserve in South Africa. In cafeteria-style food choice tests, both species preferred meat and insects over bread, dog kibble, chicken eggs, and plants; however, yellow mongoose in a more urbanised area preferred bread to insects. Yellow mongoose had a shorter latency to approach and consume provided food compared to slender mongoose. At carrion-baited stations, slender mongoose were more prevalent at carcasses and displayed aggression and competitive exclusion of yellow mongoose. Slender mongoose fed more on carcasses during the colder months than warmer months when they fed on available insects around and on carcasses. The greater consumption of anthropogenic items by yellow mongoose and the preference by slender mongoose for feeding on carcasses provide evidence of possible resource partitioning, which may aid in the co-existence of these sympatric herpestids in urban areas.

Staying safe from top predators: patterns of co-occurrence and inter-predator interactions

Top predators often have cascading effects on mesopredator communities by driving behavioural changes. Using camera-trapping surveys, we explored the site-detection probability of sympatric predators and temporal overlap and examined behavioural patterns to explore hypotheses of carnivore guild interactions between and within large and small predators in the presence/absence of lion (Panthera leo) in open and closed habitat cover. We used single-season two-species occupancy models to test inter-predator interactions at 205 camera sites spread across five Protected Areas of the Maputaland Conservation Unit, South Africa. These data showed the respective associations between the presence of large carnivores and smaller carnivores. We observed that leopard (Panthera pardus) and hyena (Crocuta crocuta) tended to avoid interference encounters, as they were less likely co-detected at the same sites. There was a decrease in detection of leopard and hyena as a function of lion presence. Small predators such as the group honey badger (Mellivora capensis)-striped polecat (Ictonyx striatus) and the slender mongoose (Herpestes sanguineus) were detected less often at cameras where leopards were detected. Detection probabilities of the group badger-polecat and slender mongoose were much higher in the closed habitat than in open habitat where leopards were detected. At camera sites where hyenas were detected, badger-polecat and genet (Genetta tigrina) detection probability was much higher in the closed habitat than open habitat. Slender mongoose overlapped less temporally with large predators while others did not. Our study showed that large predator guilds can affect the probability of detecting subordinate mesopredators; therefore, reintroduction of large carnivores can have a cascading effect on subordinate carnivores, and it is necessary to consider this effect when planning recovery programmes for carnivore conservation. We think this study is of importance and interest as top predators often shape mesopredator communities by inducing apparent avoidance behaviour based on associations between the presence of large carnivores and smaller carnivores. As a consequence, smaller predators use closed habitat to minimize the risk of larger predators due to intraguild interference interaction. We explored behavioural patterns of sympatric predators’ site detection probability and temporal overlap and examined hypotheses about carnivore guild interactions between leopard and spotted hyena, these two and small predators with and without lion in open and closed habitat cover. Reintroduction of one carnivore population can have cascading effects on the other, and this nature of consequences needs to be accounted when planning conservation or species recovery programmes. Therefore, we extended our study to explore these important aspects. Our study is novel as there are no studies documenting species interactions between/within large and small predators from co-occurrence patterns in South Africa.

Interspecific responses of wild African carnivores to odour of 3-mercapto-3-methylbutanol, a component of wildcat and leopard urine

The scent of 3-mercapto-3-methylbutanol (3-M-3-MB), a volatile component of leopard (Panthera pardus) and domestic cat (Felis silvestris catus) urine, released at about 10 ng/s from slow-release dispensers, elicited scent-marking from African civet (Civettictis civetta), small-spotted genet (Genetta genetta) and slender mongoose (Galerella sanguinea), as well as African wildcat (F. s. cafra). A female leopard was apparently repelled by the scent. The scent-marking and scent-rubbing by species other than African wildcats and leopards were unexpected and have important implications for the design of studies to investigate chemical communication between wild mammals and the use of camera traps to estimate animal numbers. Videos showing the behaviours referred to in this article are available at; http://www.momo-p.com/showdetail-e.php?movieid=momo161223fs01a; http://www.momo-p.com/showdetail-e.php?movieid=momo161223gs01a; http://www.momo-p.com/showdetail-e.php?movieid=momo161223gg01a.

Life history patterns and biology of the slender mongoose (Galerella sanguinea) in the Kalahari Desert

The mongoose family (Herpestidae) has provided a wealth of data on life history patterns and behavior of its more social species but little is known about the many solitary mongoose species. Here, we provide the 1st long-term data on life history patterns and the biology of the solitary slender mongoose (Galerella sanguinea) in the Kalahari Desert, South Africa. Slender mongooses are strictly diurnal, solitary foragers, opportunistically hunting vertebrates and invertebrates. Life history patterns, such as a prolonged period of offspring dependence, including age at 1st emergence, at 1st foraging, and at weaning, compared to social meerkats (Suricata suricatta), seem to be an adaptation to their mainly solitary life style.

Female-biased dispersal in the solitarily foraging slender mongoose, Galerella sanguinea, in the Kalahari

Sex-biased dispersal is common in most mammals, but a female bias is less so and exceptionally rare in solitary mammals. Here we present genetic and observational evidence for strong female-biased dispersal in a solitary foraging small carnivore, the slender mongoose. We suggest that females benefit from dispersal by avoiding kin competition over local resources and inbreeding, while males can benefit from philopatry through kin cooperation leading to an increased success in female defence. The comparison between our observations and those of a previous study in Tanzania suggest that there is ecologically influenced flexibility in dispersal patterns within this species, influencing sex-specific benefits of dispersal and philopatry. Comparing our results with those on the closely related, more social mongoose species in which both sexes commonly disperse suggests that dispersal patterns are linked to a species' social system by the opportunity, or lack of it, in philopatry to obtain unrelated mating partners and gain indirect fitness benefits.

Modelling large spotted genet (Genetta tigrina) and slender mongoose (Galerella sanguinea) occupancy in a heterogeneous landscape of South Africa

Drivers of distribution patterns of poorly known species are among the most important aspects in conservation biology. We studied the proportion of area occupied by the large spotted genet (Genetta tigrina) and the slender mongoose (Galerella sanguine) in response to land use variables using camera-trapping data in Drakensberg Midlands, South Africa. Average estimated occupancy of large spotted genet and slender mongoose were 0.42±0.10 and 0.41±0.04 respectively using single season occupancy models. Altitudinal variation was found to be significant in the distribution of both species, along with human abundance for genet and availability of bushland for mongoose. Autumn influenced detection probability of both species negatively, while summer influenced slender mongoose positively. Relative human abundance was positively associated with detection probability of slender mongoose, and for large spotted genet, availability of bushland influenced positively while relative abundance of jackal (Canis mesomelas) influenced negatively. Occurrence of both species suggests that high elevations may not provide favourable ecological conditions, and bush cover appeared to be favourable habitats for both species. Either positive occurrence or detection of small carnivores to human abundance indicated their tendency to subsist in low-lying human populated areas. The present study shows the influence of a range of factors on the distribution of lesser known carnivores.

Species boundaries and possible hybridization between the black mongoose (Galerella nigrata) and the slender mongoose (Galerella sanguinea)

Major climatic oscillations since the mid-Miocene climatic optimum are known to have played a key role in promoting speciation events. In this study we use molecular data to elucidate the evolutionary history of Galerella nigrata and link its divergence to known major climatic events. A total of 51 samples from G. nigrata and 17 from Galerella sanguinea were used to provide the first molecular evidence that G. nigrata may be a species in its own right. Both mitochondrial cytochrome b and the nuclear ß-fibrinogen intron seven sequences of G. nigrata form distinct monophyletic clades, separate from its sister species G. sanguinea. We estimate the divergence of these two species to have occurred 3.85–4.27million years ago, coinciding with a period of the Plio-Pleistocene that was characterised by cooling global temperatures and strong aridity in southern Africa. However, evidence for potential hybridization between the two species was documented for ten individuals using phenotypic (pelage colouration) and/or molecular (nuclear and mtDNA sequences and microsatellite loci) data. There appeared to be a bias towards unidirectional hybridization with all potential hybrids showing mtDNA haplotypes from G. nigrata. We suggest that as the desert expanded across Namibia, G. sanguinea likely retreated with the savanna, leaving some mongooses stranded on the granite inselbergs of north-western Namibia. Subsequent adaptation of these mongooses to local conditions on granite inselbergs could have led to ecological speciation. Secondary contact zones would have been re-established with subsequent global warming events. It appears that the two species have not yet undergone complete reproductive isolation.

Topography of the chorda tympani nerve and the tensor tympani muscle in carnivores provides a new synapomorphy for Herpestidae (Carnivora, Mammalia)

The topographical relationship of the chorda tympani nerve (chorda tympani) to the tensor tympani muscle in the middle ear of carnivores provides new phylogenetic information. The examination of histological serial sections of 16 carnivore species representing most families revealed two distinct character states concerning the course of the chorda tympani: a hypotensoric state with the nerve running below the insertion tendon of the tensor tympani muscle, and an epitensoric state with the nerve running above the tendon. The shift from the plesiomorphic hypotensoric chorda tympani to the apomorphic epitensoric condition occurred once in carnivore phylogeny: Only in the herpestid species under study does the chorda tympani cross above the tensor tympani muscle. Therefore, we introduce the epitensoric pattern as a new synapomorphy for herpestids. Within the herpestids we find the following structural distinctions: Herpestes javanicus and Galerella sanguinea have a chorda tympani running in a sulcus directly above the insertion of the tensor tympani muscle, whereas in the eusocial herpestid species Suricata suricatta and Mungos mungo the chorda tympani lies far above the insertion of the muscle.

Shrub encroachment affects mammalian carnivore abundance and species richness in semiarid rangelands

Shrub encroachment due to overgrazing has led to dramatic changes of savanna landscapes and is considered to be one of the most threatening forms of rangeland degradation e.g. via habitat fragmentation. Mammalian carnivores are particularly vulnerable to local extinction in fragmented landscapes. However, our understanding of how shrub encroachment affects mammalian carnivores is poor. Here we investigated the relative sensitivities of ten native carnivores to different levels of shrub cover ranging from low (<5%) to high shrub cover (>25%) in 20 southern Kalahari rangeland sites. Relative abundance of carnivores was monitored along 40 sand transects (5 m × 250 m) for each site. Our results show that increasing shrub cover affects carnivore species differently. African wild cats, striped polecats, cape foxes and suricates were negatively affected, whereas we found hump-shaped responses for yellow mongooses, bat-eared foxes and small-spotted genets with maximum abundance at shrub covers between 10 and 18%. In contrast, black-backed jackals, slender mongooses and small spotted cats were not significantly affected by increasing shrub cover. However, a negative impact of high shrub cover above 18% was congruent for all species. We conclude that intermediate shrub cover (10–18%) in savanna landscapes sustain viable populations of small carnivores.