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The article offers information about a study which explores the abundance of lion, or Panthera leo, and spotted hyaena, or Crocuta crocuta in Bouba Ndjida National Park in Cameroon. Other information about the low carnivore densities and poor infrastructure in Central Africa as well as the materials and methods used in the study is presented.

Comprehensive studies of Palaeolithic sites and the application of modern analytical techniques are still incredibly rare in coastal central Italy. In this paper, we present the Middle-Upper Palaeolithic cave deposits excavated in the travertine quarry of Cava Muracci (Cisterna di Latina, central Italy) and summary describe the multidisciplinary approach carried out on findings discovered therein. A large faunal assemblage, fossil faeces (coprolites) and a small lithic collection have been examined along with reliable dating analyses for the interpretation of the context. The site proved to be extensively frequented by cave hyena (Crocuta crocuta spelaea) between 34-44 ka BP, with a marginal human presence also attested. This study demonstrates that a holistic approach is crucial for enhancing our understanding of the archaeological context of the area, previously interpreted using studies of fauna or lithic industries alone. The evidence gathered from Cava Muracci and the results from their study provide a valuable reference database from which to draw upon for future investigations. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The internal cranial morphology of the bone-cracking hyena Pliocrocuta perrieri (Carnivora, Hyaenidae) is described based on three crania from the late Pliocene and early Pleistocene of the Iberian Peninsula. The shape and size of the inner cranial cavities (with emphasis on encephalization and relative regional brain volumes) are compared with those of extant hyaenids with the aid of computed tomography techniques-which had not been previously used to study the brain morphology of any extinct bone-cracking hyena. Our results indicate that the frontal sinuses of P. perrieri are caudally extended and overlap the brain cavity, as in other extinct and extant bone-cracking hyaenids. In turn, the brain morphology and sulcal pattern of P. perrieri are more similar to those of Hyaena hyaena and Parahyaena brunnea than to those of Crocuta crocuta among extant bone-cracking hyaenids. Our results further indicate that Pliocrocuta is clearly less encephalized than the highly-social Crocuta, and displays an anterior cerebrum relatively smaller than in all extant bone-cracking hyenas (indicating the possession of a poorly-developed frontal cortex). These facts might suggest that P. perrieri possessed less developed cognitive abilities than Crocuta for processing the information associated with complex social behaviors. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the presence of Echinococcus spp. in wild mammals of Kenya, 832 faecal samples from wild carnivores (lions, leopards, spotted hyenas, wild dogs and silver-backed jackals) were collected in six different conservation areas of Kenya (Meru, Nairobi, Tsavo West and Tsavo East National Parks, Samburu and Maasai Mara National Reserves). Taeniid eggs were found in 120 samples (14.4%). In total, 1160 eggs were isolated and further analysed using RFLP-PCR of the nad1 gene and sequencing. 38 of these samples contained eggs of Echinococcus spp., which were identified as either Echinococcus felidis (n=27) or Echinococcus granulosus sensu stricto (n=12); one sample contained eggs from both taxa. E. felidis was found in faeces from lions (n=20) and hyenas (n=5) while E. granulosus in faeces from lions (n=8), leopards (n=1) and hyenas (n=3). The host species for two samples containing E. felidis could not be identified with certainty. As the majority of isolated eggs could not be analysed with the methods used (no amplification), we do not attempt to give estimates of faecal prevalences. Both taxa of Echinococcus were found in all conservation areas except Meru (only E. felidis) and Tsavo West (only E. granulosus). Host species identification for environmental faecal samples, based on field signs, was found to be unreliable. All samples with taeniid eggs were subjected to a confirmatory host species RLFP-PCR of the cytochrome B gene. 60% had been correctly identified in the field. Frequently, hyena faeces were mistaken for lion and vice versa, and none of the samples from jackals and wild dogs could be confirmed in the tested sub-sample. This is the first molecular study on the distribution of Echinococcus spp. in Kenyan wildlife. The presence of E. felidis is confirmed for lions and newly reported for spotted hyenas. Lions and hyenas are newly recognized hosts for E. granulosus s.s., while the role of leopards remains uncertain. These data provide the basis for further studies on the lifecycles and the possible link between wild and domestic cycles of cystic echinococcosis in eastern Africa. [Copyright &y& Elsevier]

The article presents the findings of a study conducted on examining the taxonomic position of Crocuta sivalensis by restudy of the type specimen. The metric analysis reveals that species of Crocuta and Pliocrocuta are difficult to distinguish on morphology alone. It concludes that taxon is a junior subjective synonym of Pliocrocuta perrieri. It highlights the comparison between the illustrations of fossil studies conducted by W. E. Baker and R. Lydekker and the photographs indicating that the specimens are identical.

The article discusses a study on changing adaptability in the diet of carnivorous animal hyena (Crocuta crocuta) to anthropogenic food sources. It informs that hyenas can digest all part of their prey except hair and grooves. It informs that hyenas are completely dependent on human related sources for food in North Ethiopia due to lack of natural prey base. It mentions wildlife species are adapting changes for their survival in the environment.

Abstract: Animals that hunt and scavenge are often exposed to a broad array of pathogens. Theory predicts the immune systems of animals specialized for scavenging should have been molded by selective pressures associated with surviving microbial assaults from their food. Spotted hyenas (Crocuta crocuta) are capable hunters that have recently descended from carrion feeding ancestors. Hyenas have been documented to survive anthrax and rabies infections, and outbreaks of several other viral diseases that decimated populations of sympatric carnivores. In light of the extreme disease resistance manifested by spotted hyenas, our objective was to identify tools available for studying immune function in spotted hyenas and use these tools to document the hyena antibody response to immunization. Domestic cats (Felis catus) are the closest phylogenetic relatives of hyenas that have been studied in detail immunologically, and we hypothesized that anti-cat isotype-specific antibodies would cross react with hyena immunoglobulin epitopes. We used ELISA and Western blots to test isotype-specific anti-feline antibodies for specific cross-reaction to hyena Ig epitopes. Molecular weights of heavy (IgA, IgG, IgM) and light chains of hyena immunoglobulins were determined by protein electrophoresis, and as expected, they were found to be similar to feline immunoglobulins. In order to further validate the cross-reactivity of the anti-feline antibodies and document the hyena humoral response, eight spotted hyenas were immunized with dinitrophenol conjugated keyhole limpet hemocyanin (DNP-KLH) and serum anti-DNP responses were monitored by enzyme-linked immunosorbent assay (ELISA) for one year. The full array of isotype-specific antibodies identified here will allow veterinarians and other researchers to thoroughly investigate the hyena antibody response, and can be used in future studies to test hypotheses about pathogen exposure and immune function in this species. [Copyright &y& Elsevier]

Risk is a fundamental driver of prey behaviour, but the importance of risk in the decision-making processes of top predators is poorly understood. We investigated the functions of vigilance behaviour in wild spotted hyaenas. These large carnivores have few predators but face frequent threats of attack and food theft by conspecifics. We made repeated observations of vigilance behaviour by hyaenas when they were resting, feeding and nursing, and examined variation due to age, group size, social rank, and factors related to predation risk. We used these observations to test whether vigilance functions in hyaenas to detect prey, mates, conspecific threats or interspecific threats, and whether functions differ between juveniles and adults. We found that adults were more vigilant than juveniles in all contexts. Vigilance by adults was greatest when nursing, but nursing females reduced their vigilance as cubs matured. Among both age groups, vigilance decreased with increasing group size, and hyaenas were less vigilant when feeding on high-quality food than when feeding on low-quality food. Social rank did not affect vigilance in either age group. Individual adults, but not juveniles, showed consistent patterns of vigilance within, but not between, behavioural contexts. Surprisingly, our results indicate that the primary function of vigilance in hyaenas is to detect interspecific threats. Furthermore, vigilance was context specific, and adult hyaenas showed individual variation in vigilance within behavioural contexts. These findings illustrate the relative importance of particular risks in shaping vigilance behaviour of a top carnivore. [Copyright &y& Elsevier]

Abstract: Our aim was to identify natural and anthropogenic influences on the stress physiology of large African carnivores, using wild spotted hyenas (Crocuta crocuta) as model animals. With both longitudinal data from a single social group, and cross-sectional data from multiple groups, we used fecal glucocorticoids (fGC) to examine potential stressors among spotted hyenas. Longitudinal data from adult members of a group living on the edge of the Masai Mara National Reserve, Kenya, revealed that fGC concentrations were elevated during two periods of social upheaval among adults, especially among younger females; however, prey availability, rainfall, and presence of lions did not influence fGC concentrations among hyenas. Our results suggested that anthropogenic disturbance in the form of pastoralist activity, but not tourism, influenced fGC concentrations among adult male hyenas; rising concentrations of fGC among males over 12 years were significantly correlated with increasing human population density along the edge of the group''s home range. As hyenas from this social group were frequently exposed to anthropogenic disturbance, we compared fGC concentrations among these hyenas with those obtained concurrently from hyenas living in three other groups undisturbed by pastoralist activity. We found that fGC concentrations from the undisturbed groups were significantly lower than those in the disturbed group, and we were able to rule out tourism and ecological stressors as sources of variation in fGC among the populations. Thus it appears that both social instability and anthropogenic disturbance, but not the ecological variables examined, elevate fGC concentrations and represent stressors for wild spotted hyenas. Further work will be necessary to determine whether interpopulation variation in stress physiology predicts population decline in groups exposed to intensive anthropogenic disturbance. [Copyright &y& Elsevier]

Abstract: Fecal hormone analysis is a useful tool for frequent, non-invasive sampling of free-living animals. Estrogens fluctuate throughout life among reproductive states in female animals, and intensive repetitive sampling can permit accurate assessment of female reproductive condition. This type of repetitive sampling is difficult in large carnivores, including the spotted hyena (Crocuta crocuta). Patterns of estrogen secretion in captive and free-living hyenas are virtually unknown. Here we present validation of an enzyme-immunoassay to measure fecal estrogen (fE) concentrations in wild and captive spotted hyenas. Results from high-performance liquid chromatography indicate that an antibody specific for estradiol exhibits high immunoreactivity with our extracted samples. Fecal extract displacement curves paralleled our estradiol standard curve within the range of 20–80% antibody binding. Additionally, animals treated with luteinizing hormone-releasing hormone showed a measurable rise in fE concentrations. Finally, once we controlled for effects of time of day of sample collection from wild hyenas, patterns in fE concentrations resembled those in plasma estradiol, including higher levels of fE in mature than immature females, and higher levels of fE during late than early pregnancy. Together, these results suggest that fE concentrations reflect circulating estrogens in spotted hyenas. [Copyright &y& Elsevier]

Integrated field and laboratory studies of long-lived, large-bodied mammals are rare but offer unique opportunities to elucidate the behavioral ecology of these animals. Here, we used this approach to examine whether siblicide in spotted hyenas (Crocuta crocuta) is obligate or facultative. First, we tested predictions of obligate and facultative hypotheses by using ultrasonography to compare litter size before and after parturition and identify potential causes of litter reduction. Second, we compared litter size and composition between wild and captive hyenas to assess variation in offspring sex ratios. Third, we used demographic data to compare survivorship among litters of various sizes and compositions. Fourth, we compared sex ratios within twin litters born in the wild under conditions of high population density and intense feeding competition with those born when population density and intensity of feeding competition were reduced. Our data were inconsistent with the obligate siblicide hypothesis. Litter reduction occurred during roughly one-third of pregnancies in both wild and captive hyenas, and all such reductions among captives were due to fetal resorptions or stillbirths. Litter sizes and compositions differed little between wild and captive hyenas. However, sex ratios in twin litters varied in the wild with intensity of feeding competition. In conjunction with captive data, long-term study of a wild hyena population under varying environmental conditions suggests facultative siblicide is most likely to occur when feeding competition is most intense, thus offering an ecological explanation for earlier conflicting reports on siblicide in this species. [ABSTRACT FROM PUBLISHER]

We describe a miniaturized infrared camera mounted on a remotely operated platform (burrow probe system) that we developed to investigate spotted hyena (Crocuta crocuta) cubs while still in their natal dens. In conjunction with the burrow probe system, we used a hook system to retrieve carcasses from within burrows. To test the utility of these systems, we compared results obtained using the burrow probe and hook to results obtained from intensive above-ground monitoring alone. With the probe, we documented births and litter sizes at significantly younger ages than with above-ground monitoring. The probe was instrumental in detecting cubs that died prior to emergence from the natal den. Retrieval of carcasses allowed collection of genetic samples and data on sex and cause of death. Thus, the burrow probe and hook systems can provide scientists and managers with empirical data on productivity and neonatal mortality of carnivores in the wild; data essential to accurately monitor and model population trends. [ABSTRACT FROM AUTHOR]

Female spotted hyenas (Crocuta crocuta) are larger and more aggressive than males, and their genitalia are heavily 'masculinized'. These odd traits in females pose unusual challenges for males during courtship and copulation. Here our goals were to describe and quantify the behavior patterns involved in courtship and copulation in Crocuta, and determine whether rates of affiliative behavior directed toward females by males vary with female age, social rank, or time to conception. We also inquired whether consort formation with a particular female was necessary for a male to sire that female's cubs. Behavioral observations and paternity data based on 12 microsatellite loci were collected over 11 years from free-ranging hyenas in Kenya. Several of the courtship displays exhibited by male hyenas differed from those found in other carnivores, and appeared to reflect intense motivational conflict between tendencies to approach and flee from females. Most male advances were either ignored by females or elicited aggression from females toward males. Rates of male affiliative behavior toward females peaked around the time of conception. Although males behaved similarly toward young and old females in the highest social rank category, males directed more affiliative behavior toward older than younger females that were mid- and low-ranking. Multiple short mounts usually preceded a long mount, but intromission and ejaculation appeared to occur only during long mounts. Female receptivity was indicated by inhibited aggression toward the male and assumption of a distinctive receptive stance. The only behavior indicative of female proceptivity was following of the male by the female in mating contexts. Some males who sired cubs formed consortships with females whereas others did not, suggesting that individual male hyenas may adopt alternative reproductive tactics to attract and acquire mates. Our results also suggest that low fertility may be an important cost of female virilization in this species. [ABSTRACT FROM AUTHOR]

Large brains and great intelligence are metabolically costly, but the social complexity hypothesis suggests that these traits were favored nonetheless in primates by selection pressures associated with life in complex societies. If so, then cognitive abilities and nervous systems with primatelike attributes should have evolved convergently in nonprimate mammals living in large, elaborate societies in which social dexterity enhances individual fitness. Societies of spotted hyenas (Crocuta crocuta) are remarkably similar to those of cercopithecine primates with respect to size, structure, and patterns of competition and cooperation. These similarities set an ideal stage for comparative analysis of social intelligence and nervous system organization. As in cercopithecine primates, spotted hyenas use multiple sensory modalities to recognize their kin and other conspecifics as individuals, they know that some group-mates are more valuable social partners than others, they recognize 3rd-party kin and rank relationships among their clan-mates, and they use this knowledge adaptively during social decision-making. Examination of the available data strongly suggests convergent evolution of intelligence between spotted hyenas and primates. Evidence that less gregarious members of the family Hyaenidae lack some of the cognitive abilities found in spotted hyenas would provide further support for the idea that social complexity favors enhancement of intelligence in mammals. [ABSTRACT FROM AUTHOR]

It has long been recognized that vocal signals communicate information about the age, sex and affective state of callers. However, the mechanisms by which these types of information are communicated are less well understood. Here we investigated variation in the acoustic properties of the long-distance vocalizations, called 'whoops', emitted by free-living spotted hyenas, Crocuta crocuta. Specifically we investigated whether the fundamental frequency, length and rate of whoops provide information about the caller's age, sex and/or level of arousal. We determined the latter by contrasting whoops emitted spontaneously with whoops emitted during periods of social excitement, when callers typically also exhibited visual signals associated with heightened arousal. We found that the minimum fundamental frequency of a whoop provides reliable information about the caller's general age and, for adult callers, information about sex as well. The vast majority of adult male whoop bouts were emitted spontaneously, but juveniles and adult females produced many of their bouts during periods of social excitement. Although context did not significantly affect the whoop bouts of adult females, juvenile bouts emitted during social excitement had higher maximum fundamental frequencies, greater proportions of asymmetric whoop subtypes, and reduced inter-whoop intervals. By reducing the inter-whoop intervals of bouts, juvenile hyenas significantly increased the likelihood that conspecifics would respond to whoops by approaching the caller or its social companion. Peak fundamental frequency and the relative abundance of whoop subtypes did not appreciably affect response. We discuss the potential functions of whooping by juvenile and adult hyenas in light of these findings. [ABSTRACT FROM AUTHOR]

Spotted hyaenas Crocuta crocuta were once considered mere scavengers; however, detailed research revealed that they are very efficient predators. Information on what spotted hyaenas actually prefer to prey on and what they avoid is lacking, as well as the factors that influence prey selection. Data from 14 published and one unpublished study from six countries throughout the distribution of the spotted hyaena were used to determine which prey species were preferred and which were avoided using Jacobs' index. The mean of these values for each species was used as the dependent variable in multiple regression, with prey abundance and prey body mass as predictive variables. In stark contrast to the rest of Africa's large predator guild, spotted hyaenas do not preferentially prey on any species. Also surprisingly, only buffalo, giraffe and plains zebra are significantly avoided. Spotted hyaena most prefer prey within a body mass range of 56–182 kg, with a mode of 102 kg. The dietary niche breadth of the spotted hyaena is similar to that of the lion Panthera leo, and the two species have a 58.6% actual prey species overlap and a 68.8% preferred prey species overlap. These results highlight the flexible and unselective nature of spotted hyaena predation and are probably a reason for the species' success throughout its range, despite a large degree of dietary overlap with lions. [ABSTRACT FROM AUTHOR]

The spotted hyena (Crocuta crocuta), the most common large carnivore in the highlands and lowlands of Ethiopia, Eritrea, and Somalia, has occupied both a scavenging niche and a predatory position at the top of the food chain. My own field explorations on this animal and the observations of travelers document its long and ambivalent association with people in the Horn of Africa. Spotted hyenas in this region have mostly lived in anthropogenic contexts rather than, as in East Africa, on wildlife. Tolerated as efficient sanitation units, hyenas have removed garbage and carrion from towns. They have also destroyed livestock, killed people, and eaten corpses. Famine, epidemics, and armed conflict have provided opportunities for unbridled anthropophagy. The past and present coming together of human and hyena in this multiethnic region can be viewed as a vestige of a primeval African ecological relationship that dates far back in prehistory. Biological processes offer a deeper framework than culture with which to grasp the inherent contradiction of the hyena/human relationship past and present. [ABSTRACT FROM AUTHOR]

Spotted hyaenas utilize isolated natal dens (NDs) and communal dens (CDs) for rearing their cubs. Here we describe patterns of natal and CD occupation by hyaenas belonging to one well-studied clan in the Maasai Mara National Reserve during a 10-year period. Locations of 98 den sites that were used as natal or CDs by hyaenas in the study clan were digitized in a Geographic Information System, and the duration of use of each den site, frequency of re-use, and distances involved in den moves were quantified. Hyaenas moved their CD monthly on average. Most CD sites were occupied only once during the study, but several sites were used repeatedly. On rare occasions, the movement of hyaenas to a new den site could be attributed to a disturbance event at the CD, but factors regularly prompting hyaenas to move to new CD sites were unclear. High-ranking female hyaenas were more likely to rear their cubs from birth in a CD than low-ranking females. Low-ranking females almost always utilized isolated NDs for the first few weeks of a litter's development, and low-ranking females transferred their cubs over longer distances than did high-ranking females. [ABSTRACT FROM AUTHOR]

Abstract: The four extant species of hyenas (Hyaenidae; Carnivora) form a morphologically and ecologically heterogeneous group of feliform carnivorans that are remnants of a formerly diverse group of mammalian predators. They include the aardwolf (Proteles cristatus), a termite-feeding specialist, and three species with a craniodental morphology adapted to cracking the bones of prey and/or carcasses, the spotted hyena (Crocuta crocuta), brown hyena (Parahyaena brunnea), and striped hyena (Hyaena hyaena). Hyenas have been the subject of a number of systematic studies during the last two centuries, due in large part to the extensive fossil record of the group, with nearly 70 described fossil species. Morphological studies incorporating both fossil and living taxa have yielded different conclusions regarding the evolutionary relationships among living hyenas. We used a molecular supermatrix comprised of seven nuclear gene segments and the complete mitochondrial cytochrome b gene to evaluate phylogenetic relationships among the four extant hyaenid species. We also obtained sequence data from representative species of all the main families of the Feliformia (Felidae, Herpestidae, and Viverridae) to estimate the sister group of the Hyaenidae. Maximum parsimony and maximum likelihood analyses of the supermatrix recovered identical topologies. Furthermore, Bayesian phylogenetic analyses of the supermatrix, with among-site rate variation among data partitions parameterized in three different ways, also yielded the same topology. For each phylogeny reconstruction method, all but two nodes received 100% bootstrap or 1.00 posterior probability nodal support. Within the monophyletic Hyaenidae, Parahyaena and Hyaena were joined together, with Crocuta as the sister to this clade, and Proteles forming the most basal lineage. A clade containing two species of mongoose (core Herpestidae) plus Cryptoprocta ferox (currently classified in Viverridae) was resolved as the sister group of Hyaenidae. The pattern of relationships among the three bone-cracking hyaenids (Crocuta, Hyaena, and Parahyaena) is incongruent with recent cladistic assessments based on morphology and suggests the need to reevaluate some of the morphological characters that have been traditionally used to evaluate relationships among hyenas. Divergence time estimates based on a Bayesian relaxed molecular clock indicates that hyaenids diverged from their feliform sister group 29.2 MYA, in the Middle Oligocene. Molecular clock estimates also suggest that the origin of the aardwolf is much more recent (10.6 MYA) than that implied by a cladistic analysis of morphology (∼20 MYA) and suggests that the aardwolf is possibly derived from a bone and meat eating lineage of hyaenids that were present in the Late Miocene. [Hyaenidae; phylogeny; cytochrome b; nuclear gene segments; Proteles; Crocuta; Hyaena; Parahyaena.] [Copyright &y& Elsevier]

Androgens influence many physiological processes in male vertebrates and have been linked to variation in aggression and reproductive behaviour in many species. This study examined relationships between social behaviour and androgens excreted by adult male spotted hyaenas. In this species, males rarely direct reproductive aggression towards other males, but they actively court females that are socially dominant to them. We tested whether intersexual interactions were associated with elevated androgens in adult males. We combined behavioural data collected over 7 years from one large clan in Kenya with analysis of faecal androgens (fA) to determine which of the following were the best predictors of fA concentrations in males: social rank, tenure in the clan, courtship, association with females in particular reproductive states, reproductive aggression among males or nonreproductive aggression among males. We found no systematic influence of age or social status on fA in either adult natal or immigrant males. Concentrations of fA were greater in immigrants when they courted females than at other times, and greater fA concentrations were also associated with male–male aggression involving defence of a female but not with male–male aggression occurring in other contexts. fA concentrations in immigrants were also positively correlated with degree of association with females near the time of conception, but not with lactating females. These findings suggest that androgen concentrations in immigrant male hyaenas are more related to interactions with attractive females than to competitive male interactions. The most important challenge to adult males may be interacting with attractive females to which males are socially subordinate. [Copyright &y& Elsevier]

Observational and telemetry data were used in a geographic information system database to document the ontogenetic development of sexually dimorphic patterns of space use among free-living spotted hyenas Crocuta crocuta in Kenya. No measures of space use were sexually dimorphic among den-dwelling cubs, nor were sex differences apparent among hyenas that had ceased using dens for shelter until these animals were c. 30 months of age. Significant sex differences emerged late in the third year of life, and persisted throughout the remainder of the life span; males were found farther from the geographic centre of the natal territory than were females, and the mean size of individual 95% utility distributions was larger for males than females. Most dispersal events by radio-collared males were preceded by a series of exploratory excursions outside the natal territory. All collared males dispersed, but no collared females did so. Most dispersing males moved only one or two home ranges away at dispersal, roughly 8–10 km distant from the natal territory, before settling in a new social group. [ABSTRACT FROM AUTHOR]

Abstract: New materials from the middle part of the Bahe formation are described as Dinocrocuta gigantea. Review of the species reveals that it is derived in the evolutionary lineage of Dinocrocuta, and biochronologically later than Vallesian records from Turkey. The only possibly related Vallesian species from China is Crocuta gigantea xizangensis from Biru, Tibet, which may prove to be conspecific with D. senyureki. Based on the mammalian faunal sequence from Lantian, and with reference to Red Clay paleomagnetic data, the duration of D. gigantea in China should be later late Miocene, rather than the previously postulated early late Miocene (Vallesian equivalent) age. [Copyright &y& Elsevier]

The social complexity hypothesis posits that natural selection has favoured the evolution of intelligence in animals living in challenging social environments. Although several primate species have been shown to use information about the social relationships between conspecifics in activities such as recruiting allies or reconciling after fights, this ability to recognize third-party relationships has never been demonstrated in nonprimate mammals. However, the social complexity hypothesis predicts that nonprimates should show some of the same cognitive abilities as primates when many features of their social lives resemble those of primates. Here we tested this prediction with data from a group of free-living spotted hyaenas, Crocuta crocuta, which are gregarious carnivores that live in primate-like societies. First, we examined whether hyaenas consistently supported dominant animals over subordinates when they joined in dyadic fights. The hyaenas overwhelmingly supported the dominant animal in each fight, even when both fighting animals ranked below the supporter, and even when the dominant individual was losing the fight. Next, we examined whether hyaenas preferentially attacked relatives of their opponents after a fight. We found that they were more likely to attack relatives of their opponents after a fight than during a control period, and that they were also more likely to attack relatives of their opponents than to attack low-ranking animals unrelated to their opponents. These results suggest that hyaenas can recognize third-party relationships, and support the idea that social complexity drives the evolution of intelligence in phylogenetically disparate taxa. [Copyright &y& Elsevier]

Spotted hyenas (Crocuta crocuta ) are gregarious carnivores. The females are socially dominant to males, and adult males rarely direct aggression toward adult females. This study analyzed all cases in which adult immigrant males behaved aggressively toward adult females in a large population of free-living hyenas in Kenya, observed for 11 years. Our goals were to describe the conditions under which male attacks on females occur, and address possible adaptive functions. Most aggression directed by adult immigrant males against females occurred when coalitions of two or more males attacked a single adult female, who typically responded by defending herself and fighting back. Male aggression against females frequently occurred at sites of ungulate kills, but males never behaved aggressively toward females over food, and all male attacks on females were unprovoked. Although no mounting or other copulatory behaviors ever occurred during or immediately after an attack, the number of male attacks on females peaked around the time of conception. Daily rates at which males attacked females did not vary with female social rank. However, daily attack rates did vary significantly with female reproductive state, and the highest rates of male attack on females were observed during the two stages of the reproductive cycle during which females were most likely to conceive litters. The adaptive significance of male aggression against females in this species remains unknown, but a tight association between male attacks on females and a female's time of conception provides strong evidence of some role for male aggression in hyena sexual behavior. In particular, our data are consistent with hypotheses suggesting that male aggression toward females in this species either serves to inform females about male fitness or represents sexual harassment. Aggr. Behav. 29:457–474, 2003. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The purpose of this study was to document patterns of reproductive skew among male spotted hyenas (Crocuta crocuta), a species in which many normal mammalian sex roles are reversed. We used paternity determined from 12 microsatellite markers together with demographic and behavioral data collected over 10 years from a free-living population to document relationships among reproductive success (RS), social rank, and dispersal status of male hyenas. Our data suggest that dispersal status and length of residence are the strongest determinants of RS. Natal males comprise over 20% of the adult male population, yet they sire only 3% of cubs, whereas immigrants sire 97%. This reproductive advantage to immigrants accrues despite the fact that immigrants are socially subordinate to all adult natal males, and it provides a compelling ultimate explanation for primary dispersal in this species. High-ranking immigrants do not monopolize reproduction, and tenure accounts for more of the variance in male reproductive success than does social rank. Immigrant male hyenas rarely fight among themselves, so combat between rivals may be a relatively ineffectual mode of sexual selection in this species. Instead, female choice of mates appears to play an important role in determining patterns of paternity in Crocuta. Our data support a “limited control” model of reproductive skew in this species, in which female choice may play a more important role in limiting control by dominant males than do power struggles among males. [ABSTRACT FROM AUTHOR]

A long-term study of immigrant male spotted hyenas (Crocuta crocuta) living in large multimale/multifemale groups (clans) demonstrated that males acquire social status by queuing. Maximum likelihood estimates of parameters of a stochastic queuing model that assessed queuing discipline confirmed that immigrant males respected the convention that their positions in a queue of typically 15 or more individuals was determined by their sequence of arrival. Levels of aggression among males were low; males did not attempt to improve their social status through physical contests. Size and body mass did not influence male social status. The stability of queues was insured by an increase in the rate at which males formed coalitions against other males as they rose in social status and by coalitions between high-ranked males and dominant females. High-ranked, long-tenured males chiefly consorted with (“shadowed”) and focused their affiliative behavior on females of high reproductive value and disrupted attempts by subordinate males to associate with these females. High-ranked males also supported females against lower-ranked males that harassed them. In contrast, lower-ranked, short-tenured males focused their affiliative behavior on young adult females and rarely shadowed or defended females. Males that did not disperse from their natal clan (nondispersers) quickly acquired top rank in the male social hierarchy. Irrespective of the social status acquired from their mother when young, nondisperser adult males submitted to all adult females. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

SummaryThe feeding behaviour of the Talek clan of spotted hyaenas in the Masai Mara National Reserve, Kenya, was monitored continuously for 7 years. Talek hyaenas adapted to large temporal variations in prey abundance by being opportunistic predators. During the first half of the year, the hyaenas fed on resident ungulates, and their diet consisted mainly of topi and Thomson's gazelles. Upon arrival of the migratory herds of wildebeest and zebra from the Serengeti, Talek hyaenas switched to feeding on the wildebeest which provided them with a superabundance of food for about 3 months. After the migratory animals returned to the Serengeti, Talek hyaenas experienced a period of reduced prey abundance due to the temporary dispersion of resident ungulates. At this time hyaenas hunted the few remaining wildebeest, and also increased their use of the remaining resident animals. Although Talek hyaenas were generally opportunistic in their feeding behaviour, they did exhibit clear dietary preference for larger prey species, particularly wildebeest. Finally, carrion comprised only 5% of the biomass consumed by Talek hyaenas, the lowest proportion of carrion in the diet of any Crocuta population studied to date. [ABSTRACT FROM AUTHOR]

The article presents information related to a study on carcasses deposited by spotted hyenas in Lake Macat, at the Ngorongoro Crater in Tanzania. The study, conducted by the author, analyzed the availability and freshness of the tissues of carcasses. There were carcasses of four adult wildebeest and one adult Grant's gazelle found by the author. It is anticipated that carcasses caching behavior found in spotted hyenas is specific to a species which evolved in a long time period. It is informed that hyenas deposited most of the carcasses 10- 20 meters from the lake's edge in shallow water.

The intra-montane Guadix-Baza Basin is one of the few continental basins in Europe that hosts a well-dated set of fossiliferous sites spanning from the latest Miocene to the late Middle Pleistocene. The Cúllar de Baza 1 (CB-1) represents a key site to investigate the effects of the Early-Middle Pleistocene Transition, considered a fundamental transformation in the Earth's climate state. Our review and update of the large mammal assemblage, and particularly equids, is of paramount relevance to understand the systematic affinities and the evolution of the Early and Middle Pleistocene European horses. We confirm the occurrence of two different taxa, the medium sized Equus altidens and the larger E. suessenbornensis. Moreover, we illustrate that CB-1 is essential for the biochronological studies of the latest Early Pleistocene/Middle Pleistocene transition (Epivillafranchian/Galerian ELMA); in particular with regard to the Last Occurrences of the Etruscan rhino Stephanorhinus etruscus and the large deer Megaloceros savini and the First Occurrence of the water-rat Arvicola mosbachensis in the Iberian peninsula. Finally, a development of a mosaic environment characterised the CB-1 site contrasting with the conditions reported for other Iberian late Early and Middle Pleistocene localities. • Cúllar Baza 1 is crucial to investigate the Early-Middle Pleistocene Transition. • Equus altidens and E. suessenbornensis occurred at Cúllar Baza 1. • Last Occurrence of the rhino Stephanorhinus etruscus in the Iberian peninsula. • Last Occurrence of the large deer Megaloceros savini in the Iberian peninsula. • Cúllar Baza 1 was characterised by a mosaic environment. [ABSTRACT FROM AUTHOR]

This paper presents pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves in southern Spain (Granada), with the aim of reconstructing the environmental conditions of these hominin sites. The LV coprolites are radiocarbon dated from c. 37,890 to 6980 cal yr BP, and the Car coprolites from c. 31,063 to 7861 cal yr BP. Overall, the palaeoecological scenario inferred from both coprolite series display similar patterns, with Pinus , Poaceae, and Artemisia as dominant during the full Pleistocene, and an important contribution of Quercus in the most recently dated coprolite samples. While the palynology is consistent with results of former investigations on the past environments in the region as obtained from other deposits (peat bogs, cave infills), the Late Glacial and Holocene chronology of several coprolites in both sites is in conflict with the generally accepted timing of extinction of Crocuta in western Europe. A discussion on the taphonomical processes and potential sources of carbon contamination of the radiocarbon samples is provided. The correlation between pollen from coprolites and from sedimentary records, and the paucity of the fossil bone record suggests nevertheless, that a late survival of Crocuta in southern Spain should not be categorically discarded. • New pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves. • The palaeoecological scenario inferred from both coprolite series display similar patterns. • Timing of extinction of Crocuta in western Europe. • A late survival of Crocuta in southern Spain should not be categorically discarded. [ABSTRACT FROM AUTHOR]

Integrated field and laboratory studies of long-lived, large-bodied mammals are rare but offer unique opportunities to elucidate the behavioral ecology of these animals. Here, we used this approach to examine whether siblicide in spotted hyenas (Crocuta crocuta) is obligate or facultative. First, we tested predictions of obligate and facultative hypotheses by using ultrasonography to compare litter size before and after parturition and identify potential causes of litter reduction. Second, we compared litter size and composition between wild and captive hyenas to assess variation in offspring sex ratios. Third, we used demographic data to compare survivorship among litters of various sizes and compositions. Fourth, we compared sex ratios within twin litters born in the wild under conditions of high population density and intense feeding competition with those born when population density and intensity of feeding competition were reduced. Our data were inconsistent with the obligate siblicide hypothesis. Litter reduction occurred during roughly one-third of pregnancies in both wild and captive hyenas, and all such reductions among captives were due to fetal resorptions or stillbirths. Litter sizes and compositions differed little between wild and captive hyenas. However, sex ratios in twin litters varied in the wild with intensity of feeding competition. In conjunction with captive data, long-term study of a wild hyena population under varying environmental conditions suggests facultative siblicide is most likely to occur when feeding competition is most intense, thus offering an ecological explanation for earlier conflicting reports on siblicide in this species. [ABSTRACT FROM AUTHOR]