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The Tip-Tugai Cave (52°59'28.6â³ N, 57°00'22.3â³ E) is described as a new site with cave hyena Crocuta spelaea fossils. The bone-bearing layer was dated to marine isotope stage (MIS) 3 based on the species composition of the fauna of large and small mammals. Finds of abundant remains of cave hyenas of different ages and bones of large herbivores with hyena gnaw marks indicated that the Tip-Tugai Cave was used as a hyena den in the Late Pleistocene. This is the first cave hyena den described in the Urals.
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Collective action problems arise when cooperating individuals suffer costs of cooperation, while the benefits of cooperation are received by both cooperators and defectors. We address this problem using data from spotted hyenas fighting with lions. Lions are much larger and kill many hyenas, so these fights require cooperative mobbing by hyenas for them to succeed. We identify factors that predict when hyena groups engage in cooperative fights with lions, which individuals choose to participate and how the benefits of victory are distributed among cooperators and non-cooperators. We find that cooperative mobbing is better predicted by lower costs (no male lions, more hyenas) than higher benefits (need for food). Individual participation is facilitated by social factors, both over the long term (close kin, social bond strength) and the short term (greeting interactions prior to cooperation). Finally, we find some direct benefits of participation: after cooperation, participants were more likely to feed at contested carcasses than non-participants. Overall, these results are consistent with the hypothesis that, when animals face dangerous cooperative dilemmas, selection favours flexible strategies that are sensitive to dynamic factors emerging over multiple time scales.
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Hyaenidae , Leones , Animales , HumanosRESUMEN
Scavenging is widespread in the carnivore guild and can greatly impact food web structures and population dynamics by either facilitation or suppression of sympatric carnivores. Due to habitat loss and fragmentation, carnivores are increasingly forced into close sympatry, possibly resulting in more interactions such as kleptoparasitism and competition. In this paper, we investigate the potential for these interactions when carnivore densities are high. A camera trap survey was conducted in central Tuli, Botswana, to examine leopard Panthera pardus densities and spatiotemporal activity patterns of leopard and its most important competitors' brown hyena Parahyaena brunnea and spotted hyena Crocuta crocuta. Spatial capture-recapture models estimated leopard population density to be 12.7 ± 3.2 leopard/100 km2, which is one of the highest leopard densities in Africa. Time-to-event analyses showed both brown hyena and spotted hyena were observed more frequently before and after a leopard observation than expected by chance. The high spatiotemporal overlap of both hyena species with leopard is possibly explained by leopard providing scavenging opportunities for brown hyena and spotted hyena. Our results suggest that central Tuli is a high-density leopard area, despite possible intense kleptoparasitism and competition.
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Communication relies on signals that can be produced via different sensory modalities to modify receivers' behavior. During social interactions, the possibility to perceive subtle visual cues enhances the use of facial expressions to exchange information. One of the most appropriate fields to explore the specific design features of visual signals is play fighting. Here, we explored the production and potential role of Relaxed Open Mouth (ROM) and Head Bobbing (HB) in regulating play fighting of wild spotted hyenas Crocuta crocuta, a highly hierarchical carnivore species. In accordance with the assumptions of the signal optimization theory, wild hyenas produced ROM and HB almost exclusively when the sender was in direct visual contact with the receiver thus suggesting that senders were attentive to the playmates' face. Contrary to HB, the sequential analysis revealed that ROM often anticipated offensive patterns such as play biting thus supporting the hypothesis that ROM, but not HB, is a metacomunicative signal. Moreover, when the offensive patterns were biased toward one of the 2 players, the session was punctuated by a higher number of ROMs. Our findings support the general hypothesis that these 2 visual signals can play different roles in the management of play fighting in this carnivore species. The complementary use of ROM and HB would suggest that spotted hyenas are highly competent and fast in processing facial displays of different nature to correctly "read others' intentions" and respond with appropriate motor actions to avoid misunderstanding during one of the most multifaceted and risky social interaction.
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Large carnivores increasingly inhabit human-affected landscapes, which exhibit heterogeneity in biotic resources, anthropogenic pressures, and management strategies. Understanding large carnivore habitat use in these systems is critical for their conservation, as is the evaluation of competing management approaches and the impacts of significant land-use changes. We used occupancy modeling to investigate habitat use of an intact eastern African large carnivore guild across the 45,000 km2 Ruaha-Rungwa landscape in south-central Tanzania. We determined the relative impact on five large carnivore species of biotic, anthropogenic, and management factors at the scales of home range selection and short-term use within home ranges. We also specifically tested the effect of abandonment of trophy hunting areas on large carnivore occurrence. Patterns of habitat use differed among species. Lions (Panthera leo) appeared affected by top-down limitation, as their occurrence was significantly negatively associated with illegal human activity (ß = -0.63 [SE 0.28]). African wild dogs (Lycaon pictus), instead, were limited by biotic features; the species was negatively associated with riverine areas of high sympatric predator density (ß = -1.00 [SE 0.43]) and used less-productive habitats. Spotted hyaena (Crocuta crocuta) and leopard (Panthera pardus) persisted in more disturbed areas and across habitat types. Large carnivore occurrence was not affected by whether an area was used for photographic or trophy hunting tourism; regular law enforcement was instead a better predictor of occurrence. All species fared better in actively managed hunting areas than those that had been abandoned by operators. Overall, our findings highlight the divergent habitat requirements within large carnivore guilds and the importance of adopting an integrated approach to large carnivore conservation planning in modern systems. We also identified a novel threat to African conservation areas in the form of decreased management investments associated with the abandonment of trophy hunting areas.
Uso de Hábitat y Amenazas para los Grandes Carnívoros de África en un Paisaje de Uso Mixto Resumen Cada vez más, los grandes carnívoros habitan paisajes afectados por los humanos, los cuales presentan heterogeneidad en los recursos bióticos, las presiones antropogénicas y las estrategias de manejo. El conocimiento sobre cómo usan el hábitat los grandes carnívoros en estos sistemas es crucial para su conservación, como lo es la evaluación de las estrategias competitivas de manejo y los impactos de los cambios significativos en el uso de suelo. Usamos modelos de ocupación para investigar el uso de hábitat por parte de un gremio intacto de grandes carnívoros en el este de África a lo largo de los 45,000 km2 del paisaje Ruaha-Rungwa en el centro-sur de Tanzania. Determinamos el impacto relativo que tienen los factores bióticos, antropogénicos y de manejo sobre cinco especies de grandes carnívoros a escala de selección de extensión doméstica y uso a corto plazo dentro de la extensión doméstica. También analizamos específicamente el efecto que tiene el abandono de las áreas de caza de trofeos sobre la presencia de los grandes carnívoros. Los patrones de uso de hábitat difirieron entre las especies. Los leones (Panthera leo) parecieron estar afectados por la limitación de arriba-abajo ya que su presencia estuvo asociada negativamente de manera importante con la actividad humana ilegal (ß = - 0.63 [SE 0.28]). El perro salvaje africano (Lycaon pictus) estuvo limitado por los elementos bióticos; la especie estuvo asociada negativamente con las áreas de alta densidad simpátrica de depredadores (ß = - 1.00 [SE 0.43]) y utilizó los hábitats menos productivos. La hiena moteada (Crocuta crocuta) y el leopardo (Panthera pardus) persistieron en áreas más perturbadas y en todos los tipos de hábitat. La presencia de los grandes carnívoros no se vio afectada si el área se usaba para caza de trofeos o turismo fotográfico; la aplicación regular de la ley fue un mejor pronóstico de la presencia. A todas las especies les fue mejor en las áreas de caza con gestión activa que en aquellas abandonadas por los operadores. En general, nuestros descubrimientos resaltan los distintos requerimientos de hábitat dentro de los gremios de grandes carnívoros y la importancia de adoptar un enfoque integrado para la planeación de la conservación de estas especies en los sistemas modernos. También identificamos una amenaza nueva para las áreas de conservación africana a manera de inversiones de manejo disminuidas asociadas con el abandono de las áreas de caza de trofeos.
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Carnívoros , Leones , Panthera , Animales , Humanos , Conservación de los Recursos Naturales , Conducta Predatoria , EcosistemaRESUMEN
Robust measures of animal densities are necessary for effective wildlife management. Leopards (Panthera pardus) and spotted hyenas (Crocuta Crocuta) are higher order predators that are data deficient across much of their East African range and in Uganda, excepting for one peer-reviewed study on hyenas, there are presently no credible population estimates for these species. A lack of information on the population status and even baseline densities of these species has ramifications as leopards are drawcards for the photo-tourism industry, and along with hyenas are often responsible for livestock depredations from pastoralist communities. Leopards are also sometimes hunted for sport. Establishing baseline density estimates for these species is urgently needed not only for population monitoring purposes, but in the design of sustainable management offtakes, and in assessing certain conservation interventions like financial compensation for livestock depredation. Accordingly, we ran a single-season survey of these carnivores in the Lake Mburo National Park of south-western Uganda using 60 remote camera traps distributed in a paired format at 30 locations. We analysed hyena and leopard detections under a Bayesian spatially explicit capture-recapture (SECR) modelling framework to estimate their densities. This small national park (370 km2) is surrounded by Bahima pastoralist communities with high densities of cattle on the park edge (with regular park incursions). Leopard densities were estimated at 6.31 individuals/100 km2 (posterior SD = 1.47, 95% CI [3.75-9.20]), and spotted hyena densities were 10.99 individuals/100 km2, but with wide confidence intervals (posterior SD = 3.35, 95% CI [5.63-17.37]). Leopard and spotted hyena abundance within the boundaries of the national park were 24.87 (posterior SD 7.78) and 39.07 individuals (posterior = SD 13.51) respectively. Leopard densities were on the middle end of SECR studies published in the peer-reviewed literature over the last 5 years while spotted hyena densities were some of the first reported in the literature using SECR, and similar to a study in Botswana which reported 11.80 spotted hyenas/100 km2. Densities were not noticeably lower at the park edge, and in the southwest of our study site, despite repeated cattle incursions into these areas. We postulate that the relatively high densities of both species in the region could be owed to impala Aepyceros melampus densities ranging from 16.6-25.6 impala/km2. Another, potential explanatory variable (albeit a speculative one) is the absence of interspecific competition from African lions (Panthera leo), which became functionally extinct (there is only one male lion present) in the park nearly two decades ago. This study provides the first robust population estimate of these species anywhere in Uganda and suggests leopards and spotted hyenas continue to persist in the highly modified landscape of Lake Mburo National Park.
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Antílopes , Carnívoros , Hyaenidae , Leones , Panthera , Masculino , Animales , Bovinos , Lagos , Parques Recreativos , Teorema de Bayes , Uganda , GanadoRESUMEN
Toxoplasma gondii is a common parasite that infects warm-blooded animals and influences host physiology. T. gondii is known to target the host's central nervous system, affecting circulating levels of steroid hormones, fear-related behaviors, and health, although these effects appear to vary among host taxa. Here, we investigated the relationship between T. gondii infection and levels of plasma testosterone and cortisol within a wild population of spotted hyenas (Crocuta crocuta, n = 109). In our analyses, we accounted for age and sex via stratified regression analyses. We detected a negative association between circulating plasma testosterone and T. gondii infection among female cubs and subadults as well as adult male hyenas. We found no associations between T. gondii infection and cortisol in any age class or sex group of hyenas. Our work adds to a growing body of literature by characterizing the relationship between T. gondii infection and physiology in a novel host in its natural habitat. In a broader context, our findings indicate that responses to infection vary with characteristics of the host and point to a clear need for additional studies and priorities for future work that include diverse taxa and ecological settings.
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Salivary hormone analyses provide a useful alternative to fecal and urinary hormone analyses in non-invasive studies of behavioral endocrinology. Here, we use saliva to assess cortisol levels in a wild population of spotted hyenas (Crocuta crocuta), a gregarious carnivore living in complex social groups. We first describe a novel, non-invasive method of collecting saliva from juvenile hyenas and validate a salivary cortisol assay for use in this species. We then analyze over 260 saliva samples collected from nearly 70 juveniles to investigate the relationships between cortisol and temporal and social variables in these animals. We obtain some evidence of a bimodal daily rhythm with salivary cortisol concentrations dropping around dawn and dusk, times at which cub activity levels are changing substantially. We also find that dominant littermates have lower cortisol than singleton juveniles, but that cortisol does not vary with age, sex, or maternal social rank. Finally, we examine how social behaviors such as aggression or play affect salivary cortisol concentrations. We find that inflicting aggression on others was associated with lower cortisol concentrations. We hope that the detailed description of our methods provides wildlife researchers with the tools to measure salivary cortisol in other wild carnivores.
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Carnívoros , Hyaenidae , Animales , Animales Salvajes , Heces , Hidrocortisona , SalivaRESUMEN
The spotted hyena (Crocuta crocuta Erxleben) and the lion (Panthera leo Linnaeus) are two of the most abundant and charismatic large mammalian carnivores in Africa and yet both are experiencing declining populations and significant pressures from environmental change. However, with few exceptions, most studies have focused on influences upon spotted hyena and lion populations within individual sites, rather than synthesizing data from multiple locations. This has impeded the identification of over-arching trends behind the changing biomass of these large predators. Using partial least squares regression models, influences upon population biomass were therefore investigated, focusing upon prey biomass, temperature, precipitation, and vegetation cover. Additionally, as both species are in competition with one other for food, the influence of competition and evidence of environmental partitioning were assessed. Our results indicate that spotted hyena biomass is more strongly influenced by environmental conditions than lion, with larger hyena populations in areas with warmer winters, cooler summers, less drought, and more semi-open vegetation cover. Competition was found to have a negligible influence upon spotted hyena and lion populations, and environmental partitioning is suggested, with spotted hyena population biomass greater in areas with more semi-open vegetation cover. Moreover, spotted hyena is most heavily influenced by the availability of medium-sized prey biomass, whereas lion is influenced more by large size prey biomass. Given the influences identified upon spotted hyena populations in particular, the results of this study could be used to highlight populations potentially at greatest risk of decline, such as in areas with warming summers and increasingly arid conditions.
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We have investigated the relationship between spotted hyaenas in the south Namib Desert and large herbivorous prey and have summarized an updated overview of predator-prey relationships in this resource-limited arid environment. Over the 52-month study, we recorded the densities (#/km-2, ±SE) of the four local large herbivorous prey species: gemsbok (1.229, ±0.50), springbok (1.352, ±0.48), ostrich (0.648, ±0.23), and greater kudu (0.343, ±0.00). A fecal analysis was performed on 146 collected spotted hyaena scats, and prey items were identified and hairs cross-follicle analyzed to the species level. Spotted hyaena diet at the study area remained opportunistic with 240 identified prey items representing eight differing prey species being recorded, ranging from ostrich eggs to large ungulates. The Ivlev's Electivity Index was used to determine which large herbivorous prey was most selected for. Although gemsbok had a higher representation of prey items in the sampled scats, all sampled large herbivorous prey species scored below 0 and are thus generally avoided in relation to their availability in the environment. If any prey preferences are expressed by spotted hyaena in the Namib, it can be presumed to be a nonsampled prey species. We therefore promote further detailed investigations into all other prey species present, and seasonal variations of prey densities and scat sampling, within the study environment.
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Apex predators play important roles in ecosystem functioning and, where they coexist, intraguild interactions can have profound effects on trophic relationships. Interactions between predators range from intraguild predation and competition to facilitation through scavenging opportunities. Despite the increased availability of fine-scale GPS data, the determinants and outcomes of encounters between apex predators remain understudied. We used simultaneous GPS data from collared spotted hyaenas (Crocuta crocuta) and African lions (Panthera leo) in Hwange National Park, Zimbabwe, to determine the environmental conditions of the encounters between the two species, which species provoked the encounter, and which species dominated the encounter. Our results show that encounters between hyaenas and lions are mostly resource-related (over a carcass or around waterholes). In the wet season, encounters mainly occur at a carcass, with lions being dominant over its access. In the dry season, encounters mainly occur in the absence of a carcass and near waterholes. Movements of hyaenas and lions before, during, and after these dry-season encounters suggest two interference scenarios: a passive interference scenario whereby both predators would be attracted to waterholes but lions would leave a waterhole used by hyaenas because of prey disturbance, and an active interference scenario whereby hyaenas would actively chase lions from waterhole areas, which are prime hunting grounds. This study highlights the seasonal dynamics of predator interactions and illustrates how the relative importance of negative interactions (interference competition during the dry season) and positive interactions (scavenging opportunities during the wet season) shifts over the course of the year.
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Ecosistema , Leones , Animales , Conducta Predatoria , Estaciones del AñoRESUMEN
Hunting preferences reveal a great deal about the life of Paleolithic humans, and may reflect changes in human demography, technology, and adaptations to changing environments. However, the effects of hunting preferences and environmental availability are often conflated, stressing the need for comparisons to other predators that exploited the same environment. Manot Cave (Israel), preserved rich Early Upper Paleolithic (46-33 ka) human occupations, along with repeated spotted hyena (Crocuta crocuta) occupations, allowing us to compare anthropogenic and biogenic bone assemblages within the same space and time frame. We focused on the faunal remains retrieved in the middle of the cave (Area D), and conducted detailed taphonomic and zooarchaeological analyses. The Area D archaeofauna was dominated by Mesopotamian fallow deer (Dama mesopotamica) and mountain gazelle (Gazella gazella), which showed high abundance of carnivore damage. This and the carnivore-to-ungulate ratio, the presence of juvenile hyena and numerous coprolites match the criteria of a hyena den, confirming that the bone assemblage was created mainly by hyenas. Manot Area D thus reveals hyena prey choice in the Upper Paleolithic Galilee, which we then compared with human prey choice. Our results showed that hyena prey assemblages in Manot and elsewhere in the Levant were Dama-dominated while human assemblages were dominated by Gazella, demonstrating that hyenas and humans hunted different animal size groups, possibly in different habitats. We interpret this phenomenon as resulting from two possible scenarios: the emergence of projectile technology which may favor hunting in open environments, and niche partitioning derived by human-hyena competition. Hyenas were abundant and hunted unselectively while the anthropogenic record presents population turnovers and some dietary diversification. Whereas both scenarios are difficult to test directly with the available evidence, we argue that either one explains quite well the late Pleistocene archaeofaunal patterns in the Levantine record.
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Carnívoros , Ciervos , Hominidae , Hyaenidae , Animales , Humanos , CazaRESUMEN
How social development in early-life affects fitness remains poorly understood. Though there is growing evidence that early-life relationships can affect fitness, little research has investigated how social positions develop or whether there are particularly important periods for social position development in an animal's life history. In long-lived species in particular, understanding the lasting consequences of early-life social environments requires detailed, long-term datasets. Here we used a 25-year dataset to test whether social positions held during early development predicted adult fitness. Specifically, we quantified social position using three social network metrics: degree, strength and betweenness. We determined the social position of each individual in three types of networks during each of three stages of ontogeny to test whether they predict annual reproductive success (ARS) or longevity among adult female spotted hyenas Crocuta crocuta. The social positions occupied by juvenile hyenas did predict their fitness, but the effects of social position on fitness measures differed between stages of early development. Network metrics when individuals were young adults better predicted ARS, but network metrics for younger animals, particularly when youngsters were confined to the communal den, better predicted longevity than did metrics assessed during other stages of development. Our study shows how multiple types of social bonds formed during multiple stages of social development predict lifetime fitness outcomes. We suggest that social bonds formed during specific phases of development may be more important than others when considering fitness outcomes.
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Hyaenidae , Animales , Femenino , Longevidad , Reproducción , Medio SocialRESUMEN
Wildlife respond to human presence by adjusting their temporal niche, possibly modifying encounter rates among species and trophic dynamics that structure communities. We assessed wildlife diel activity responses to human presence and consequential changes in predator-prey overlap using 11,111 detections of 3 large carnivores and 11 ungulates across 21,430 camera trap-nights in West Africa. Over two-thirds of species exhibited diel responses to mainly diurnal human presence, with ungulate nocturnal activity increasing by 7.1%. Rather than traditional pairwise predator-prey diel comparisons, we considered spatiotemporally explicit predator access to several prey resources to evaluate community-level trophic responses to human presence. Although leopard prey access was not affected by humans, lion and spotted hyena access to three prey species significantly increased when prey increased their nocturnal activity to avoid humans. Human presence considerably influenced the composition of available prey, with implications for prey selection, demonstrating how humans perturb ecological processes via behavioral modifications.
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Artiodáctilos/fisiología , Hyaenidae/fisiología , Leones/fisiología , Panthera/fisiología , Conducta Predatoria , Animales , Burkina Faso , Ecosistema , Actividades Humanas , Humanos , NigerRESUMEN
Both domestic and wild carnivore species are commonly diagnosed with rabies virus (RABV) infection in South Africa. Although the majority of confirmed rabies cases in wild carnivore species are reported from the yellow mongoose (Cynictis penicillata), the rest are from other wild carnivores including the highly endangered wild dog (Lycaon pictus). Lyssavirus infection was confirmed in two wild dogs and a spotted hyaena (Crocuta crocuta) in the Madikwe Game Reserve, North West province in South Africa, in 2014 and 2015, using a direct fluorescent antibody test and immunohistochemistry. There had been no new wild dog introductions to the Madikwe Game Reserve for many years and the wild dogs were last vaccinated against rabies approximately 11 years prior to the incident. The first euthanised wild dog was the last surviving of a break-away pack of 6, and the second was the last of a larger pack of 18, the rest of which died with no carcasses being found or carcasses too decomposed for sampling. Subsequent antigenic typing of the lyssaviruses indicated that they were canid RABVs. The RABVs originating from 22 wild carnivore species, 7 dogs, and a caprine, mostly from the North West province, were genetically characterised by targeting a partial region of the nucleoprotein gene. The nucleotide sequence analyses of these viruses and two previously characterised RABVs confirmed that the outbreak viruses were also canid rabies, phylogenetically clustering with virus isolates originating from black-backed jackals recovered between 2012 and 2015 from the North West province, and domestic dogs from neighbouring communal areas. The source(s) of the mortalities and possible reservoir host(s) for the virus could only be speculated upon from data on specific predator numbers, movements and behaviour, kills, park management and the changing environmental ecology, which were monitored closely in Madikwe over several years. The most likely rabies sources were from boundary fence contacts between wild carnivores within the park, with domestic dogs or cats and/or naturally occurring wild carnivores outside the park. The associated risk of zoonotic infection and threat to important and endangered predators may be mitigated through regional rabies control primarily in domestic dogs and cats, as well as by preventative vaccination of at-risk park employees and their pets. The importance of ongoing prophylactic rabies protection by regular vaccination of highly endangered wildlife carnivores and the submission of carcasses for rabies diagnosis of any wild or domestic animals behaving uncharacteristically or found dead is emphasised.
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Animales Salvajes/virología , Canidae/virología , Hyaenidae/virología , Infecciones por Rhabdoviridae/veterinaria , Animales , Animales de Zoológico , Encéfalo/virología , Brotes de Enfermedades/prevención & control , Perros , Especies en Peligro de Extinción , Humanos , Inmunoquímica , Lyssavirus/aislamiento & purificación , Masculino , Rabia , Vacunas Antirrábicas , Infecciones por Rhabdoviridae/diagnóstico , Infecciones por Rhabdoviridae/epidemiología , Infecciones por Rhabdoviridae/prevención & control , Sudáfrica/epidemiología , Zoonosis/prevención & controlRESUMEN
BACKGROUND: The European bison (Bison bonasus), now found in Europe and the Caucasus, has been proposed to originate either from the extinct steppe/extant American bison lineage or from the extinct Bison schoetensacki lineage. Bison schoetensacki remains are documented in Eurasian Middle Pleistocene sites, but their presence in Upper Pleistocene sites has been questioned. Despite extensive genetic studies carried out on the steppe and European bison, no remains from the fossil record morphologically identified as Bison schoetensacki has been analyzed up to now. RESULTS: In this paper, we analyzed a 36,000-year-old Bison schoetensaki bone sample from the Siréjol cave (France) and a cave hyena coprolite (fossilized feces) found in a nearby cave and containing large amounts of Bovinae DNA. We show that the Bovinae mitochondrial DNA sequences from both samples, including a complete mitochondrial genome sequence, belong to a clade recently reported in the literature. This clade only includes ancient bison specimens without taxonomic identification and displays a sister relationship with the extant European bison. The genetic proximity of Bison schoetensacki with specimens from this clade is corroborated by the analysis of nuclear DNA single nucleotide polymorphisms. CONCLUSIONS: This work provides genetic evidence supporting the continuing presence of Bison schoetensacki up to the Upper Pleistocene. Bison schoetensacki turns out to be a sister species of Bison bonasus, excluding the steppe bison Bison priscus as a direct ancestor of the European bison.
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Bison/genética , Fósiles , Animales , Cuevas , ADN Mitocondrial/genética , Europa (Continente) , Francia , Genoma Mitocondrial , Filogenia , Análisis de Secuencia de ADNRESUMEN
The objective of our study was identification and molecular characterization of piroplasms and rickettsias occurring in brown (Parahyaena brunnea) and spotted hyaenas (Crocuta crocuta) from various localities in Namibia and South Africa. Whole blood (n = 59) and skin (n = 3) specimens from brown (n = 15) and spotted hyaenas (n = 47) were screened for the presence of Babesia, Theileria, Ehrlichia and Anaplasma species using the reverse line blot (RLB) hybridization technique. PCR products of 52/62 (83.9%) of the specimens hybridized only with the Theileria/Babesia genus-specific probes and not with any of the species-specific probes, suggesting the presence of a novel species or variant of a species. No Ehrlichia and/or Anaplasma species DNA could be detected. A parasite 18S ribosomal RNA gene of brown (n = 3) and spotted hyaena (n = 6) specimens was subsequently amplified and cloned, and the recombinants were sequenced. Homologous sequence searches of databases indicated that the obtained sequences were most closely related to Babesia lengau, originally described from cheetahs (Acinonyx jubatus). Observed sequence similarities were subsequently confirmed by phylogenetic analyses which showed that the obtained hyaena sequences formed a monophyletic group with B. lengau, B abesia conradae and sequences previously isolated from humans and wildlife in the western USA. Within the B. lengau clade, the obtained sequences and the published B. lengau sequences were grouped into six distinct groups, of which groups I to V represented novel B. lengau genotypes and/or gene variants. We suggest that these genotypes cannot be classified as new Babesia species, but rather as variants of B. lengau. This is the first report of occurrence of piroplasms in brown hyaenas.
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Anaplasma/clasificación , Babesia/clasificación , Ehrlichia/clasificación , Hyaenidae/parasitología , Theileria/clasificación , Anaplasma/genética , Anaplasma/aislamiento & purificación , Animales , Animales Salvajes/microbiología , Animales Salvajes/parasitología , Babesia/genética , Babesia/aislamiento & purificación , Babesiosis/epidemiología , ADN Bacteriano/genética , ADN Protozoario/genética , Ehrlichia/genética , Ehrlichia/aislamiento & purificación , Genotipo , Namibia , Técnicas de Amplificación de Ácido Nucleico , Hibridación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18S/genética , Homología de Secuencia , Sudáfrica , Theileria/genética , Theileria/aislamiento & purificaciónRESUMEN
Aggression by top predators can create a "landscape of fear" in which subordinate predators restrict their activity to low-risk areas or times of day. At large spatial or temporal scales, this can result in the costly loss of access to resources. However, fine-scale reactive avoidance may minimize the risk of aggressive encounters for subordinate predators while maintaining access to resources, thereby providing a mechanism for coexistence. We investigated fine-scale spatiotemporal avoidance in a guild of African predators characterized by intense interference competition. Vulnerable to food stealing and direct killing, cheetahs are expected to avoid both larger predators; hyenas are expected to avoid lions. We deployed a grid of 225 camera traps across 1,125 km2 in Serengeti National Park, Tanzania, to evaluate concurrent patterns of habitat use by lions, hyenas, cheetahs, and their primary prey. We used hurdle models to evaluate whether smaller species avoided areas preferred by larger species, and we used time-to-event models to evaluate fine-scale temporal avoidance in the hours immediately surrounding top predator activity. We found no evidence of long-term displacement of subordinate species, even at fine spatial scales. Instead, hyenas and cheetahs were positively associated with lions except in areas with exceptionally high lion use. Hyenas and lions appeared to actively track each, while cheetahs appear to maintain long-term access to sites with high lion use by actively avoiding those areas just in the hours immediately following lion activity. Our results suggest that cheetahs are able to use patches of preferred habitat by avoiding lions on a moment-to-moment basis. Such fine-scale temporal avoidance is likely to be less costly than long-term avoidance of preferred areas: This may help explain why cheetahs are able to coexist with lions despite high rates of lion-inflicted mortality, and highlights reactive avoidance as a general mechanism for predator coexistence.
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Increasing human population growth has led to elevated levels of human-carnivore conflict. However, some carnivore populations have adapted to urban environments and the resources they supply. Such associations may influence carnivore ecology, behaviour and life-history. Pockets of urbanisation sometimes occur within protected areas, so that anthropogenic influences on carnivore biology are not necessarily confined to unprotected areas. In this study we evaluated associations between human infrastructure and related activity and space use of spotted hyaenas within one of the largest protected areas in South Africa, the Kruger National Park. Home range size was smaller for the dominant female of a clan living in close proximity to humans than that of the dominant female of a clan without direct access to human infrastructure. The home range including human infrastructure was also used less evenly during the night, presumably when the animals were active. Within this home range, a village area was preferred during the night, when the least modified areas within the village were preferred and administration and highly modified areas were avoided. During the day, however, there were no preference or avoidance of the village area, but all habitats except unmodified habitats within the village area were avoided. We suggest that human infrastructure and associated activity influenced hyaena space use, primarily through alterations in the spatial distribution of food. However, these effects may have been indirectly caused by habitat modification that generated favourable hunting habitat rather than a direct effect caused by access to human food such as garbage. Because of the often pivotal effects of apex predators in terrestrial ecosystems, we encourage further work aimed to quantify how human presence influences large carnivores and associated ecosystem processes within protected areas.
RESUMEN
BACKGROUND: Where apex predators move on the landscape influences ecosystem structure and function and is therefore key to effective landscape-level management and species-specific conservation. However the factors underlying predator distribution patterns within functional ecosystems are poorly understood. Predator movement should be sensitive to the spatial patterns of inter-specific competitors, spatial variation in prey density, and landscape attributes that increase individual prey vulnerability. We investigated the relative role of these fundamental factors on seasonal resource utilization by a globally endangered apex carnivore, the African lion (Panthera leo) in Tanzania's Serengeti National Park. Lion space use was represented by novel landscape-level, modified utilization distributions (termed "localized density distributions") created from telemetry relocations of individual lions from multiple neighbouring prides. Spatial patterns of inter-specific competitors were similarly determined from telemetry re-locations of spotted hyenas (Crocuta crocuta), this system's primary competitor for lions; prey distribution was derived from 18 months of detailed census data; and remote sensing data was used to represent relevant habitat attributes. RESULTS: Lion space use was consistently influenced by landscape attributes that increase individual prey vulnerability to predation. Wet season activity, when available prey were scarce, was concentrated near embankments, which provide ambush opportunities, and dry season activity, when available prey were abundant, near remaining water sources where prey occurrence is predictable. Lion space use patterns were positively associated with areas of high prey biomass, but only in the prey abundant dry season. Finally, at the broad scale of this analysis, lion and hyena space use was positively correlated in the comparatively prey-rich dry season and unrelated in the wet season, suggesting lion movement was unconstrained by the spatial patterns of their main inter-specific competitors. CONCLUSIONS: The availability of potential prey and vulnerability of that prey to predation both motivate lion movement decisions, with their relative importance apparently mediated by overall prey abundance. With practical and theoretical implications, these results suggest that while top carnivores are consistently cognizant of how landscape features influence individual prey vulnerability, they also adopt a flexible approach to range use by adjusting spatial behaviour according to fluctuations in local prey abundance.