ABSTRACT
Conservation of wide-ranging species and their movement is a major challenge in an increasingly fragmented world. Long-distance movement, such as dispersal, is a key factor for the persistence of population, enabling the movement of animals within and between populations. Here, we describe one of the longest dispersal journeys by a sub-adult male tiger (Panthera tigris) through GPS telemetry in Central India. We analyzed movement metrics, directionality, and space use during three behavioral stages of dispersal. We also used the clustering method to identify resting and kill sites (n = 89). T1-C1 dispersed a straight-line distance of 315 km over 225 days, moving an average of 8.38 km/day and covering a cumulative displacement of ~3000 km. Movement rate during post-dispersal was faster (mean = 0.47 km/h) than during dispersal (mean = 0.38 km/h) and pre-dispersal (mean = 0.13 km/h), respectively. The overall movement rate during the night (0.44 km/h) was significantly faster than during the day (0.21 km/h). Likewise, during dispersal, the movement was faster (mean = 0.52 km/h) at night than day (0.24 km/h). The average size of clusters, signifying resting and kill sites, was 1.68 ha and primarily away from human habitation (mean = 1.89 km). The individual crossed roads faster (mean = 2.00 km/h) than it traveled during other times. During the post-dispersal phase, T1-C1 had a space use of 319.48 km2 (95% dBBMM) in the Dnyanganga Wildlife Sanctuary. The dispersal event highlights the long-distance and multiscale movement behavior in a heterogeneous landscape. Moreover, small forest patches play a key role in maintaining large carnivore connectivity while dispersing through a human-dominated landscape. Our study underlines how documenting the long-distance movement and integrating it with modern technology can improve conservation management decisions.
ABSTRACT
Studies on resource utilisation by carnivores are essential as they aid in assessing their role in a community, by unravelling predator-prey relationships. Globally, prey depletion is one of the primary causes of declining Asiatic wild dog (dhole) populations. Therefore, it is essential to examine their diet across their range. Our study presents insights into dhole feeding ecology across multiple sites from the central Indian landscape of Maharashtra, India, for the first time. We conducted scat analysis using a subset of genetically identified scats and collected additional data from kills observed while tracking radio-collared dholes and other known packs from 2 study sites. We analysed 861 scats, and 191 dhole kills to identify species and age class of prey. We estimated the relative contribution of various prey, utilising non-linear biomass models of prey consumption. Overall, wild ungulates like sambar and chital were the principal prey in terms of biomass (sambar 61.08%; chital 19.08%) and number of prey consumed (sambar 39.28%; chital 13.83%). An analysis of kill data also suggested that dholes strongly preferred the two deer species; and differential selection of age classes was observed at the 2 study sites. Our study can potentially help manage and conserve this important population of an endangered carnivore.
Subject(s)
Canidae , Carnivora , Deer , Animals , Ecology , Forests , India , Predatory BehaviorABSTRACT
In multipredator systems, group sizes of social carnivores are shaped by the asymmetric intraguild interactions. Subordinate social carnivores experience low recruitment rates as an outcome of predation pressure. In South and Southeast Asia, the Tiger (Panthera tigris), Dhole (Cuon alpinus), and Leopard (Panthera pardus) form a widely distributed sympatric guild of large carnivores, wherein tigers are the apex predators followed by dhole and leopard. In this study, we attempted to understand the variation in pack size of a social carnivore, the dhole, at two neighboring sites in the Central Indian landscape. We further evaluated local-scale patterns of variation in pack size at a larger scale by doing a distribution-wide assessment across the dhole ranging countries. At the local scale, we found an inverse relationship between the density of tiger and pack size of dhole while accounting for variability in resources and habitat heterogeneity. Larger dhole packs (16.8 ± 3.1) were observed at the site where the tiger density was low (0.46/100 km2), whereas a smaller pack size (6.4 ± 1.3) was observed in the site with high tiger density (5.36/100 km2). Our results for the distribution-wide assessment were concordant with local-scale results, showing a negative association of pack size with the tiger densities (effect size -0.77) and a positive association with the prey abundance (effect size 0.64). The study advances our understanding to answer the age-old question of "what drives the pack size of social predators in a multipredator system?" This study also highlights the importance of understanding demographic responses of subordinate predator for varying competitor densities, often helpful in making informed decisions for conservation and management strategies such as population recovery and translocation of species.
ABSTRACT
Large carnivores play an important role in the functioning of ecosystems, yet their conservation remains a massive challenge across the world. Owing to wide-ranging habits, they encounter various anthropogenic pressures, affecting their movement in different landscape. Therefore, studying how large carnivores adapt their movement to dynamic landscape conditions is vital for management and conservation policy. A total of 26 individuals across 4 species of large carnivores of different sex and age classes (14 Panthera tigris, 3 Panthera pardus, 5 Cuon alpinus, and 4 Canis lupus pallipes) were GPS collared and monitored from 2014-19. We quantified movement parameters (step length and net squared displacement) of four large carnivores in and outside protected areas in India. We tested the effects of human pressures such as human density, road network, and landuse types on the movement of the species. We also examined the configuration of core areas as a strategy to subsist in a human-dominated landscape using BBMM. Mean displacement of large carnivores varied from 99.35 m/hr for leopards to 637.7 m/hr for wolves. Tigers outside PAs exhibited higher displacement than tigers inside PAs. Moreover, displacement during day-night was significantly different for tigers inside and outside PAs. Similarly, wolf also showed significant difference between day-night movement. However, no difference in day-night movement was found for leopard and dholes. Anthropogenic factors such as road length and proportion of agriculture within the home range of tigers outside PAs were found to be significantly different. All the habitat variables in the home range showed significant difference between the social canids. The core area size for tiger outside PA and wolf was found greater than PAs. The study on movement of large carnivore species across landscapes is crucial for conservation planning. Our findings can be a starting point for interlinking animal movement and landscape management of large carnivore conservation in the current Anthropocene.
ABSTRACT
BACKGROUND: The Asiatic wild dog or dhole (Cuon alpinus) is a highly elusive, monophyletic, forest dwelling, social canid distributed across south and Southeast Asia. Severe pressures from habitat loss, prey depletion, disease, human persecution and interspecific competition resulted in global population decline in dholes. Despite a declining population trend, detailed information on population size, ecology, demography and genetics is lacking. Generating reliable information at landscape level for dholes is challenging due to their secretive behaviour and monomorphic physical features. Recent advances in non-invasive DNA-based tools can be used to monitor populations and individuals across large landscapes. In this paper, we describe standardization and validation of faecal DNA-based methods for individual identification of dholes. We tested this method on 249 field-collected dhole faeces from five protected areas of the central Indian landscape in the state of Maharashtra, India. RESULTS: We tested a total of 18 cross-species markers and developed a panel of 12 markers for unambiguous individual identification of dholes. This marker panel identified 101 unique individuals from faecal samples collected across our pilot field study area. These loci showed varied level of amplification success (57-88%), polymorphism (3-9 alleles), heterozygosity (0.23-0.63) and produced a cumulative misidentification rate or PID(unbiased) and PID(sibs) value of 4.7 × 10-10 and 1.5 × 10-4, respectively, indicating a high statistical power in individual discrimination from poor quality samples. CONCLUSION: Our results demonstrated that the selected panel of 12 microsatellite loci can conclusively identify dholes from poor quality, non-invasive biological samples and help in exploring various population parameters. This genetic approach would be useful in dhole population estimation across its range and will help in assessing population trends and other genetic parameters for this elusive, social carnivore.
ABSTRACT
Asiatic wild dog (Cuon alpinus) or dhole is an endangered canid with fragmented distribution in South, East and Southeast Asia. The remaining populations of this species face severe conservation challenges from anthropogenic interventions, but only limited information is available at population and demography levels. Here, we describe the novel molecular approaches for unambiguous species and sex identification from noninvasively collected dhole samples. We successfully tested these assays on 130 field-collected dhole faecal samples from the Vidarbha part of central Indian tiger landscape that resulted in 97 and 77% successrates in species and sex identification, respectively. These accurate, fast and cheap molecular approaches prove the efficacy of such methods in gathering ecological data from this elusive, endangered canid and show their application in generating population level information from noninvasive samples.