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Translocations of large carnivores like tiger to restore extirpated populations are increasingly becoming important conservation tools in the face of persistent anthropogenic pressures and relentless habitat loss. Reintroduction success in Panna Tiger Reserve, India was variously attributed to high genetic diversity, less anthropogenic disturbance and stress, efficient execution and technological integrations. Here, we establish parentage relationships and explore the potential of mate choice and appropriate adult sex ratio to explain the successful reintroduction in Panna. We used a combination of radio-telemetry and genetic analyses to understand mating interactions of translocated tigers and their outcomes. Surprisingly, relatedness and parentage analyses of nine cubs born in 2010–2012 suggested that five cubs (55.5%) were not sired by the single translocated male tiger, emphasizing the difficulty of assessing the persistence of tiger presence over a large geographic area. Genotype data of tigers originally from Panna prior to the present reintroduced population revealed that four cubs were sired by an original Panna tiger which possibly ranged transiently within the released tigers’ home ranges. Presence of additional male for mate choice can be a strong factor for successful reintroduction of tigers in Panna. Although number of females released is a good indicator of reintroduction success, the number of males released is also a very important factor for success. We hypothesize that while tigers live in female-dominated population structure within male territories, mate selection strategies operate strongly between sexes. Translocation programs should therefore deliberate on this aspect of mate selection and accordingly consider founder compositions to achieve desirable results. This also reinforces the need for post-release monitoring and thorough investigations into intraspecific interactions and behavior which will facilitate proper management and revival of tiger populations.

Tigers are globally endangered and continue to decline due to poaching, prey depletion and habitat loss. In Nepal, tiger populations are fragmented and found mainly in four protected areas (PAs). To establish the use of standard methods, to assess the importance of prey availability and human disturbance on tiger presence and to assess tiger occupancy both inside and outside PAs, we conducted a tiger occupancy survey throughout the Terai Arc Landscape of Nepal. Our model-average estimate of the probability of tiger site occupancy was 0.366 [standard error (se) = 0.02, a 7% increase from the naive estimate] and the probability of detection estimate was 0.65 (se = 0.08) per 1 km searched. Modeled tiger site occupancy ranged from 0.04 (se = 0.05) in areas with a relatively lower prey base and higher human disturbance to 1 (se = 0 and 0.14) in areas with a higher prey base and lower human disturbance. We estimated tigers occupied just 5049 (se = 3) km2 (36%) of 13 915 km2 potential tiger habitat (forests and grasslands), and we detected sign in four of five key corridors linking PAs across Nepal and India, respectively indicating significant unoccupied areas likely suitable for tigers and substantial potential for tiger dispersal. To increase tiger populations and to promote long-term persistence in Nepal, otherwise suitable areas should be managed to increase prey and minimize human disturbance especially in critical corridors linking core tiger populations.

Wild, solitary felids demonstrate a variety of spacing patterns, with diversity in spatial organization largely attributed to variations in abundance and distribution of important resources, particularly prey. We examined the relationship between territoriality of female Amur tigers Panthera tigris altaica and seasonal movements of a key prey species, Manchurian red deer Cervus canadensis xanthopygus, in the Russian Far East. We predicted that despite considerable seasonal fluctuations in productivity, red deer density does not change seasonally within tigress home ranges. We analyzed radio-telemetry data to identify directional movements of deer as an indicator of relative changes in seasonal red deer abundance and distribution, and we looked for seasonal shifts in home ranges of tigresses that could signify tracking of migratory prey. We failed to detect either seasonal shifts in tigress home ranges or significant differences in seasonal prey abundance. Most red deer were sedentary, while those that migrated demonstrated varying directionality of movements. Relatively low average snow depth likely reduced directional migratory tendencies in prey populations. Despite existing theory that might predict high overlap of Amur tiger home ranges, our results suggest that exclusive spacing patterns in this tiger subspecies are at least partly explained by the absence of major spatial and temporal changes in ungulate abundance and distribution. We submit that the assumption that home-range overlap should increase with increasing home-range size may require further evaluation in cases such as that of Amur tigers.

Spatio-temporal partitioning is a viable mechanism for minimizing resource competition among sympatric species. The occurrence of sympatric large carnivores – tiger Panthera tigris, leopard Panthera pardus and dhole Cuon alpinus – in forests of the Indian subcontinent is complemented with high dietary overlap. We characterized temporal and spatial patterns of large carnivores with major prey species using photo-captures from 50 camera trap stations in Mudumalai Tiger Reserve, Western Ghats during 2008–2010. We tested whether major prey species' activity and spatial use acted as drivers for coexistence among large carnivores. Tiger exhibited cathemeral activity in the night and is spatially correlated with sambar and gaur, supporting hypotheses related to large-sized prey. Leopard was active throughout the day and is spatially correlated with almost all prey species with no active separation from tiger. Dhole exhibited diurnal activity and spatial use in relation to chital and avoided felids to a certain extent. Leopard exhibited spatial correlation with tiger and dhole, while tiger did not correlate with dhole. Leopard exhibited relatively broader temporal and spatial tolerance due to its generalist nature, which permits opportunistic exploitation of resources. This supports the hypothesis that predators actively used areas at the same time as their principal prey species depending upon their body size and morphological adaptation. We conclude that resource partitioning in large carnivores by activity and spatial use of their principal prey governs spatio-temporal separation in large carnivores.

Tigers Panthera tigris continue to decline despite the best efforts of the worldwide scientific and conservation communities. Prey depletion has been linked to this decline, but a clear definition of what constitutes preferred prey and preferred prey weight range does not exist. This is critical information if we are to assess tiger reintroduction potential, monitor unforeseen poaching of predators and prey, and successfully conserve the species. Here we reviewed the available literature on tiger diet and prey availability and calculated Jacobs's electivity index scores from 3187 kills or scats of 32 prey species. We found that wild boar and sambar deer are significantly preferred by tigers, with red deer and barasingha likely to be significantly preferred also with a larger sample size. Prey body mass was the only variable that related to tiger prey preference with species weighing between 60 and 250�kg preferred by tigers yielding a ratio of predator to preferred prey of 1:1, which is similar to other solitary felids. This information can be used to predict tiger diet, carrying capacity and movement patterns, as it has been for Africa's large predator guild, and has important implications for tiger conservation throughout its distribution.

Human,tiger conflict (HTC) fuels tiger population declines through retaliation killing by local people and government,sanctioned removal of problem individuals. This may have significant impacts on population persistence. In tigers and other large felids, broken canines are often assumed to be an infirmity that leads to HTC, but peer,reviewed literature does not support this. Thus, removal of animals with broken canines from the wild may result in unnecessary mortality. We examined data from wild Amur tigers to establish a baseline for degree of canine breakage in wild tigers not involved in conflict (referred to as “research tigers”), test for sex and age,related patterns in canine breakage, and estimate the impacts on survival and reproduction. We further compared canine breakage in research tigers to that in tigers captured or killed in HTC situations (HTC; “conflict tigers”). We detected no difference (P = 0.76) in percent of tigers with broken canines between the two groups (24% in research tigers versus 27% in conflict tigers) and no difference between sexes (P = 0.84), but the proportion of animals with broken canines increased with age class (P < 0.001). We detected no impact of canine breakage on survival or reproduction of research tigers and four research tigresses produced 1,3 litters each, despite 1,3 broken canines. Broken canines were considered a significant health issue in 2 of 17 cases, resulting in depredation in 1 case. Our data support the premise that broken canines do not usually represent a serious health issue and are usually not related to HTC. The assumption that broken canines lead to HTC appears invalid and may result in tigers being unnecessarily removed from the wild by managers. Similar results have been found for lions and the trend may be true for other large cats and carnivores as well.

Little is known about interactions between the critically endangered Sumatran tiger Panthera tigris sumatrae and its prey because of the difficulties associated with detecting these species. In this study, we quantify temporal overlap between the Sumatran tiger and five of its presumed prey species from four study areas comprising disturbed lowland to primary submontane forest. Data from 126 camera traps over 8984 camera days were used to estimate species activity patterns and, in turn, their overlap through the coefficient Δ (ranging from 0 to 1, i.e. no overlap to complete overlap). A newly developed statistical technique was applied to determine confidence intervals associated with respective overlap, which is important, as such measures of precision are usually not estimated in these types of study. Strong temporal overlap was found between tiger and muntjac Muntiacus muntjac (Δ=0.80, 95%CI=0.71–0.84) and tiger and sambar Cervus unicolor (Δ=0.81, 0.55–0.85), with the latter illustrating the importance of measuring precision. According to the foraging theory, Sumatran tigers should focus on expending lower levels of energy searching for and then capturing larger bodied prey that present the least risk. Hence, surprisingly, there was little overlap between the crepuscular tiger and the largest-bodied prey species available, the nocturnal tapir Tapirus indicus (0.52, 0.44–0.60), suggesting that it is not a principal prey species. This study provides the first insights into Sumatran tiger–prey temporal interactions. The ability to estimate overlap statistics with measures of precision has obvious and wide benefits for other predator–prey and interspecific competition studies.

We describe the food habits, niche overlap and prey preferences in a predator guild comprised of tigers Panthera tigris, leopards Panthera pardus and dholes Cuon alpinus in a mountainous region of central Bhutan. Scat analyses revealed that these predators consumed 11 different prey species including livestock and rodents, of which leopards consumed 11. The combined relative occurrence of the three species, sambar Cervus unicolor, muntjac Munticus muntjac and wild pig Sus scrofa, constituted 42.7, 33.7 and 71.1% of the tiger, leopard and dhole diets, respectively, while livestock comprised 44.5, 73.4 and 15.9% of the prey consumed, respectively. Regression equations from earlier feeding trials were used to estimate the relative biomass and the numbers of prey consumed. Results showed that sambar featured more frequently than did muntjac and wild pig in the diets of tiger, leopard and dhole and contributed more relative biomass than did muntjac and wild pig. Sambar, muntjac and wild pig together provided 36.9, 28 and 63.1% of the biomass consumed by tigers, leopards and dholes respectively. All else being equal, there was evidence that all three predators ate livestock less than might have been expected on the basis of the abundance and high biomass of this prey category in the area. There was a high dietary niche overlap between the predators (Pianka's overlap index of 0.58–0.92), with a greater overlap between the two felid species than between the felids and the canid. This study provides evidence of a substantial diet overlap among the three sympatric carnivores, and thus highlights the potential for high intra-guild competition among them, especially given the relatively low density of prey.

We examined causes of mortality and survival rates for Amur tigers on and near the Sikhote-Alin Biosphere Zapovednik. Our objectives were to estimate and compare survival rates among sex and age classes, estimate cause-specific mortality, identify conservation issues related to tiger mortality and provide recommendations for reducing human-caused mortality. We used two separate datasets; one based on radio-tracking tigers from 1992 to 2005 and one based on reports of dead tigers from 1976 to 2000. We examined causes of mortality for both datasets and used a Cox proportional hazards models to estimate survival rates using data from 42 radio-collared tigers. Mortality was predominantly human-caused for both datasets (83% for the telemetry dataset and 78% for the other, n = 24 and 53 mortalities, respectively), and 75% of collared animals were poached. All collared subadult tigers that dispersed were poached (n = 6). Annual survival of adult females (0.81 � 0.10) was greater than that of adult males (0.63 � 0.20) (z = 1.52, P= 0.13) and subadult males (0.41 � 0.46) (z = 2.07, P = 0.04). Survival rates were precariously low on our study area, which included the largest protected area within Amur tiger range. Efforts to reduce human-caused mortality should focus on poaching and reducing deaths from tiger–human conflicts.

We conducted a field study of diets of three sympatric large carnivores, the tiger Panthera tigris, the leopard Panthera pardus and the dhole Cuon alpinus in Bandipur Tiger Reserve, India, based on analyses of 381, 111 and 181 scats, respectively. The frequency of occurrence of prey items in scats was converted to relative biomass and number of prey consumed using regression equations based on earlier feeding trials. The results showed that although these predators kill ?11-15 species of vertebrate prey, relatively abundant ungulate species provide 88-97% of biomass consumed by them. Although the dietary niche overlap among the three species was high (Pianka's index of 0.75-0.93), some specialized predation was observed. The largest ungulates, gaur Bos gaurus and sambar Cervus unicolor, provided 73% of biomass consumed by tigers, whereas medium-sized chital Axis axis and wild pig Sus scrofa formed 65 and 83% of the biomass intake of leopards and dholes, respectively. In terms of the relative numbers of prey animals killed by the three predators, chital, which is the most abundant prey species, dominated their diets (tiger=33%, leopard=39% and dhole=73%). The results of the study, in conjunction with earlier work, support the prediction that abundance of ungulate prey species, as well as their availability in different size classes, are both critical factors that facilitate sympatry among the three predators.

Feeding habits of smooth-coated otters Lutra perspicillata were studied by analysing spraints collected from around the Periyar Lake within the Periyar Tiger Reserve, Kerala, India. Remains were identified by the comparison of body parts with a reference collection of appropriate prey species. Two methods were used to estimate the proportions of different prey consumed: frequency of occurrence and score-bulk estimate. The number of prey types in a spraint varied between one and seven. More prey species were found during low water levels (March–April). Fish was the major prey, followed by frogs, crabs, birds and insects. Throughout the study, the exotic tilapia and European carp constituted the major prey in the diet. The quantity of native Deccan mahsheer and endemic Periyar barb in the diet was insignificant. A higher intake of bottom-dwelling catfish was observed during periods of low water, probably because of the increased efficiency of otters to forage at these levels. By consuming large amounts of exotic species, such as tilapia and European carp, otters might contribute to the control of the rapid expansion of these species in the Periyar Lake and adjacent water bodies in the reserve.

Many small carnivores include rodents in their diet. However, due to varying evolutionary strategies, carnivores differ in their metabolism and energy requirements. Hence, comparisons of diet between carnivores would be more meaningful if the body size and energetics of the predators are considered. The diet of three small carnivores (jungle cat Felis chaus; caracal Caracal caracal; golden jackal Canis aureus) from a semi-arid part of western India was studied through scat analysis, and the importance of rodents in their diet was estimated as a percentage of their daily energy requirement. Although percentage frequency in scats and biomass consumption showed rodents to be equally important to all three carnivores, energy calculations showed that rodents were more important as prey for the felids than the jackal. Up to 70% of the daily metabolizable energy in felids was obtained from rodents, as compared to 45% in the jackal. Rodents are generally viewed as pests, and their importance to the small carnivore community is overlooked. Change in land use over the decades in the arid/semi-arid tract of western India has led to several adverse as well as favourable modifications in rodent assemblages, which could influence the persistence of species like the caracal and jungle cat in this region, that largely depend on rodents for their survival.

The tiger quoll or spotted-tailed quoll Dasyurus maculatus, a nationally threatened species, is the largest surviving carnivorous marsupial on mainland Australia and the sole surviving member of the genus in south-eastern mainland Australia. Live-trapping and radio-tracking studies at three sites in south-eastern Australia found that tiger quolls were solitary, except when mating, and that male and female tiger quolls occupied very large home ranges, both during and after the breeding season. The mean size of the home range of male tiger quolls (minimum convex polygon (MCP) 1755.4 ha, kernel 3761.7 ha) was significantly larger than the mean size of the home range of females (MCP 495.9 ha, kernel 1113.0 ha). Adult female tiger quolls displayed intrasexual territoriality throughout the year, but they seemed to tolerate the presence of female offspring. Male tiger quolls were not territorial and their home ranges overlapped both with other males and with females throughout the year. Males were recorded regularly moving back and forth between a number of female territories during the breeding season. The spatial organization of the tiger quoll recorded in this study differs markedly from that of the eastern quoll Dasyurus viverrinus and the Tasmanian devil Sarcophilus harrisii, but is similar to that of the western quoll D. geoffroii, northern quoll D. hallucatus and brush-tailed phascogale Phascogale tapoatafa. The spatial organization and home-range size of the tiger quoll dictate that conservation of the species requires management across all land tenures at the landscape level.

Food habits of tigers Panthera tigris in terms of prey abundance were studied in the semi-arid deciduous forests of Ranthambhore National Park, western India, between November 2000 and April 2001. Wild prey availability was assessed by line transects (n=8) and prey selection by the tigers was determined from analysis of scats (n=109). Compared to some other parts of the country, prey abundance was found to be high at 96.65 animals km−2. Chital Axis axis was the most abundant wild prey in the study area, followed by common langur Presbytis entellus, sambar Cervus unicolor, nilgai Boselaphus tragocamelus, wild pig Sus scrofa and chinkara Gazella bennetti. Chital (c. 31%) and sambar (c. 47%) constituted the bulk of the tigers' diet and were preferred prey. Nilgai and chinkara contributed minimally to the tigers' diet (c. 5–7% and

Food habits of tigers Panthera tigris and population attributes of prey species (population structure, density and biomass) were studied in the tropical dry deciduous forest of Pench National Park, Central India, from November 1998 to April 1999. Scat analysis and line transect method were used to estimate tiger food habits and density of major prey species, respectively. The 61.1 km2 intensive study area was found to have very high ungulate density (90.3 animals km−2) with chital Axis axis being the most common species (80.7 animals km−2), followed by sambar Cervus unicolor (6.1 animals km−2). Common langur Presbytis entellus was the most abundant (77.2 animals km−2) primate species. When the density figures were multiplied by the average weight of each prey species, a high biomass density of 6013.25 kg km−2 was obtained for the intensive study area. Chital (47.3%) along with sambar (14.5%) and wild pig Sus scrofa (10.9%) constituted the major part of the tiger's diet. If there is food choice, tigers seem to kill medium- and large-sized species more often. Wild pig and sambar were consumed more than their availability, whereas chital were taken in proportion to their availability. Gaur Bos gaurus and nilgai Bosephalus tragocamelus were not represented in the tiger's diet. Common langur was consumed in lesser proportion by tigers than expected by estimates of its density. The average weight of animals consumed by tigers in the intensive study area was 82.1 kg. The analyses revealed that Pench harbours very high prey density and tigers are mostly dependent on the wild ungulates rather than on domestic livestock as is the case in many other areas in the Indian subcontinent. These two factors thus make Pench National Park a potential area for long-term conservation of tigers.

This study examines the behavioural responses to ultrasound in 52 species from the family Cicindelidae using both tethered flight and non-flight assays. Tethered flying tiger beetles respond to trains of bat-like ultrasonic pulses with a short-latency, multi-component behaviour. There was no variation in the nature of the behavioural responses regardless of geographical distribution or phylogenetic position. Lowest mean behavioural thresholds lie predominantly between 30 and 45 kHz. Sensitivity, however, varies widely, and several species do not respond at all in these assays. The lowest thresholds for responders are most often between 70 and 80 dB SPL. Almost all subgenera of North American tiger beetles in the genus Cicindela have at least some species with low-threshold acoustic behaviour. The single exception is the large subgenus Cicindela where all species are completely unresponsive or have very high thresholds. There was little relationship between habitat and responsiveness to ultrasound, but there is a strong correlation with seasonal activity – species with adults active in the spring and autumn (all in the subgenus Cicindela ) do not show ultrasound-triggered behaviour whereas summer-active species generally do. Superimposing these data on a current phylogeny of the North American tiger beetles suggests that acoustic behaviour (and hearing) is a shared primitive trait among the taxa examined here and that there have been at least five independent losses of this character.

Behavioural factors that are likely to contribute to the coexistence of tiger Panthera tigris, leopard P. pardus and dhole Cuon alpinus, were investigated in the tropical forests of Nagarahole, southern India, during 1986–1992. Examination of predator scats and kills were combined with radiotracking of four tigers, three leopards, and visual observations of a pack of dhole. The three predators selectively killed different prey types in terms of species, size and age-sex classes, facilitating their coexistence through ecological separation. There was no temporal separation of predatory activities between tigers and leopards. Hunting activities of dholes were temporally separated from those of the two felids to some extent. Rate of movement per unit time was higher for leopards compared to tigers during day and night. In general, the activity patterns of predators appeared to be largely related to the activities of their principal prey, rather than to mutual avoidance. The three predator species used the same areas and hunted in similar habitats, although tigers attacked their prey in slightly denser cover than leopards. Both cats attacked their prey close to habitat features that attracted ungulates. There was no evidence for inter-specific spatial exclusion among predators, resulting either from habitat specificity or social dominance behaviours. Our results suggest that ecological factors, such as adequate availability of appropriate-sized prey, dense cover and high tree densities may be the primary factors in structuring the predator communities of tropical forests. Behavioural factors such as differential habitat selection or inter-specific social dominance, which are of crucial importance in savanna habitats, might play a relatively minor role in shaping the predator communities of tropical forests.

The European colonists of Tasmania named the thylacine Thylacinus cynocephalus a ‘marsupial wolf’ or the ‘Tasmanian tiger’ or ‘hyena’, in reference to its resemblance to large canids and the bold stripes on its rump. The largest marsupial carnivore in historic times, it was persecuted for alleged sheep killing and became extinct before its ecology was documented. We have reconstructed the likely prey size and the hunting and killing methods of the thylacine by comparing canine tooth strength and limb bone length ratios with those of extant marsupial and placental carnivores. The thylacine was probably a pounce–pursuit predator of fairly open habitats, which killed medium-sized prey (1–5 kg) that were small relative to its body size (15–30 kg), with a crushing, penetrating bite. The trophic niche of the thylacine was similar to that of smaller canids such as the coyote Canis latrans (rather than the wolf C. lupus), but ecomorphological convergence of the thylacine with canids was superficial. Phylogenetic constraint has resulted in unique patterns of tooth eruption, molar tooth and jaw geometry, calcaneum architecture, and perhaps FMT/running speed relationships in the Dasyuroidea.

The results of matings involving white tigers, including those during the last decade, are shown to be in accordance with the hypothesis of a single recessive autosomal gene being responsible for the characteristics “white”.

A pack of Dholes living in the Bandipur Tiger Reserve Karnataka, India was observed between August 1976 and July 1978. The home range of the pack was 40 km2, the average density was 0·35-0·9 Dholes/km2 in the 20 km2 core area. The hunting range of the pack during the denning period was 11 km2 and at other times the range was over 15 km2. Mean number of adults in the pack averaged 8·3 and including pups, the mean pack size was 16. Adult sex ratio consistently favoured ♂♂ with a 2:1 ratio. Preexisting dens were used during this study. Pups left the den when 70 to 80 days old and at seven months of age actively took part in killing prey. Means of communication, types of play, and response to other species are described. Determinants of pack size and features of pack size regulation are discussed and data are compared with those of Canis lupus and Lycaon pictus.

In the Chitawan Valley of Nepal there were estimated to be between 270 and 310 Greater one-horned or Indian rhinoceroses (Rhinoceros unicornis L.). Population densities reached 4.85 rhinos/km2 in the favoured areas of high diversity of early successional vegetation types on the valley floor. The overall population composition was 32.3% adult females, 19.9% adult males, 21.2% sub-adults and 26.6% calves. Females first calved at a mean age of 7.1 years and the median intercalving interval was 2.8 years. Causes of death included poaching, tiger predation on calves and fighting among males. The population was increasing. Rhinos fed from 183 species of plants belonging to 57 botanical families but grass (50 species) made up between 70 and 89% of their diet according to the season. Considerable seasonal variations in food availability resulted in movements of rhinos between vegetation types. Rhinos' ranges were smallest in the areas of greatest vegetational diversity. Rhinos rarely formed groups. The most common type consisted of sub-adults–mainly males. Ten auditory displays were distinguished and visual displays, although less striking, included baring the lower incisor tusks. Scents were carried in the dung, the urine and the pedal scent glands. Squirt urination and foot-dragging displays were performed by breeding males only. There was some degree of range exclusivity among breeding males but no true territoriality. Poor visibility and the relatively unpredictable distribution of resources in time and space have perhaps selected against a territorial mating system. Relationships between ecology and social organization are discussed with reference to other rhino species. Threats to the continued survival of the Indian rhino include poaching, agricultural encroachment and erosion. In order to spread the risk of a catastrophe, reintroductions of rhinos to other protected areas are proposed.