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The article discusses a study that observed two felid species including the leopard cat Prionailurus bengalensis and clouded leopard Neofelis nebulosa. Topics covered include the use of camera traps to produce the 2013 photographic evidence of the two species at the Intaki National Park in Nagaland tribal region of India where hunting are prevalent in the moist deciduos forest area. Conclusions indicated loss of many species due to tribal hunting for food consumption.

The dhole (Cuon alpinus) is an endangered social canid that inhabits the forests of southern and southeastern Asia. A scarcity of field studies and inconsistent findings have led to a poor understanding of their ecology and conservation status. We compiled an ethogram of dhole behavior based on analysis of 395.35 min of video recordings. We recorded 3,394 behavioral events in 1,654 video clips lasting 10 s each. We classified behavioral events into 6 categories: Locomotion, Resting, Social Behavior, Feeding, Scent Marking, and Miscellaneous. Behavioral events associated with Locomotion were most frequent (40.95%), as was the proportion of time spent on such behaviors (41.89%). Dholes spent the least time exhibiting Miscellaneous and Scent Marking behaviors (1.45% and 2.64%, respectively), as well as the lowest frequency (0.74% and 4.01%, respectively). Although scent marking was relatively rare, we observed unique scent-marking behaviors in this study, including "hind bounce" and "hind scrub." The time spent on different categories of behaviors differed significantly among males, females, and subadults. We also used camera traps and opportunistic observations to investigate the activity patterns of dholes in dry deciduous forest of Tadoba-Andhari Tiger Reserve in central India, where they are sympatric with other large predators including tigers (Panthera tigris) and leopards (P. pardus). Our findings suggested that dholes were primarily crepuscular. Fundamental knowledge about behavioral ecology is crucial for the conservation of any species, and our findings provide a new foundation for future behavioral research on this endangered social canid. [ABSTRACT FROM AUTHOR]

The global decline of large carnivore populations warrants scientific insights into intraguild relationships. Patterns of co-occurrence among sympatric predators are governed by their density, distribution, diet, activity overlaps, and behavioural strategies. Tigers are sympatric with leopards across their distribution range, overlap substantially in their diet, and are both nocturnal. The subdominant leopard is believed to coexist with tigers via several mechanisms like spatial segregation, temporal avoidance, and differential prey selection. Investigation of spatio-temporal patterns of co-occurrence of tigers and leopards can provide insights on mechanisms that permit coexistence. We used camera trap-based photo captures of tigers and leopards in prey-rich (58.15±10.61 ungulates per km2) Pench Tiger Reserve to determine their spatio-temporal patterns of co-occurrence. Spatially explicit density estimates of tigers were approximately 5 per 100 km2 and leopards were approximately 4.5 per 100 km2 and remained stable over the years. This implies that both these co-predators are likely to attain carrying capacity within the study area. Areas with high tiger density had lower leopard density. Quantile regression analysis between tiger and leopard density at 2×2 km grid showed that leopard density had a parabolic relationship with tiger density, initially increasing with tigers (β=0.393 ; p=0.001), stable at medium tiger density (β=0.13 and p=0.15), and declining at high tiger densities (β=-0.37 and p<0.001). Both tigers and leopards were crepuscular in nature with no temporal segregation (Δ=89 %). Time lag of consecutive leopard photograph after a tiger capture ranged between 0.002 to 36.29 d. Leopard use of trails was not related to use by tigers. Our results suggest that leopards adjust their usage of space at fine scales to avoid confrontations with tigers. We also observed high temporal overlap and no spatio-temporal segregation between tigers and leopards, despite the two predators being nocturnal and having similar prey choices. The availability of ample prey within the study area is likely to be the driving factor of the co-occurrence of tigers and leopards within this dry deciduous habitat of central India. [ABSTRACT FROM AUTHOR]

How similar species co-exist in nature is a fundamental question in community ecology. Resource partitioning has been studied in desert lizard communities across four continents, but data from South Asia is lacking. We used area-constrained visual encounter surveys to study community composition and spatial and temporal resource partitioning in a lizard community during summer in the Thar Desert, western India, addressing an important biogeographic gap in knowledge. Twelve one-hectare grids divided into 25 m × 25 m plots were placed across four habitats – barren dunes, stabilized dunes, grassland, and rocky hills. We recorded 1039 sightings of 12 species during 84 sampling sessions. Lizard abundance decreased in the order stabilized dunes > grassland > barren dunes > rocky hills; richness was in roughly the opposite order. Resource partitioning was examined for the seven commonest species. Overall spatial overlap was low (<0.6) between species pairs. Overlap was higher within habitats, but species showed finer separation through use of different microhabitat categories and specific spatial resources, as well as by positioning at different distances to vegetation. Diurnal species were also separated by peak time of activity. Space appears to be an important resource dimension facilitating co-existence in this desert lizard community. [ABSTRACT FROM AUTHOR]

Ganges River dolphins echolocate, but this mechanism is inadequate for poor sonar-echoing objects such as the monofilament gillnets, causing considerable net entanglement related mortalities. Net entanglement related deaths are one of the major causes of cetacean population decline around the world. Experiments were carried out to understand the use of pingers—an acoustic deterrent, in aiding the deterrence of dolphins from fishing nets. Based on the dolphin clicks recorded, in an experimental setup spanning 36 days, a 90% deterrence was found; 22.87 ± 0.71 SE dolphin detection positive minutes per hour near non-pingered nets versus 2.20 ± 0.33 SE per hour near pingered net. Within 30 m radii of nets, visual encounters of non-calf reduced by 52% and calf by 9%, in the presence of pingers. No evidence of habituation to pingers, habitat avoidance in dolphins after pinger removal or a change in fish catch in nets because of pingers was found during the study. While the effectiveness of pingers on calves and fish catch needs further experimentation, the use of pingers to minimize net entanglement mortalities in the Ganges River dolphins seems to be the most promising solution currently available. These results have critical implications for the conservation of other species of river dolphins around the world. [ABSTRACT FROM AUTHOR]

The article focuses on the camera-trapping records of Indian pangolins in the Shergarh Wildlife Sanctuary, emphasizing the importance of conserving these forest fragments. Topics discussed include the Indian pangolin's myrmecophagy feeding habit, the Sanctuary's diverse mammalian assemblage, and the need for stringent protection measures to safeguard pangolin populations and their habitats in the face of threats such as poaching and human disturbances.

In felids, mortality caused by dominant males can affect life history characteristics, demography and reproductive success. When a dominant male is removed, an incoming male may kill offspring sired by the previous male to induce the resident female into oestrus. We had the opportunity to observe the infanticide avoidance responses of female tigers (Panthera tigris) to incoming males in the core area of Ranthambhore Tiger Reserve (RTR), Rajasthan, during 2008-2010. In one case, following the disappearance of a dominant male tiger (TM-12) from the established territory of a female tiger (TF-13), the female tiger, accompanied by two cubs, immediately moved approximately 20 km away into riverine areas outside the protected area of RTR. In another case, a female (TF-04) died from a battle with a male while defending her cubs. These observations reveal the attempts of female tigers to avoid infanticide. Observations and results from behavioural decisions made by tigers are important to understand the species and the factors that facilitate their conservation. [ABSTRACT FROM AUTHOR]

The connectivity between landscapes is an important aspect of the conservation of small and isolated populations of carnivores. We studied the natal dispersal pattern of Bengal tigers (Panthera tigris tigris) using motion-sensitive cameras and intensive searches from April 2005 to June 2011 in Ranthambhore Tiger Reserve (RTR), western India. We tracked 29 tiger cubs (18 males, 11 females) born during the study until they established independent territories. All the females and 72.2% of the males attained maturity. The males had a greater probability (92.3%) of dispersal compared with the females (36.4%). Males dispersed an average distance of 27.0 ± 12.7 (SE) km (range = 4.5–148 km), while females dispersed an average distance of 5.7 ± 3.03 km (range = 4.6–25.8 km) from their natal area to establish their independent territories. The average age of dispersal was 38.6 ± 2.6 months (range = 24–44 months) for the males and 27.7 ± 2.7 months (range = 25–33 months) for the females. Seven of the 11 females bred at >48 months' age, after establishing independent territories. Of the other females, three were translocated to another protected area, and one died after the dispersal. This study adds to the baseline information about the dispersal patterns of tigers, which is important in making conservation and management decisions for restoration of tiger populations. • We tracked 29 tiger cubs (18 male and 11 females) born during the study until they established independent territories. • Males had a greater probability (92.3%) of dispersal than females (36.4%). • Out of 11 females, 7 breed at >48 months after establishing independent territories. • This study provides base line information for conservation and management decisions for tiger restoration. [ABSTRACT FROM AUTHOR]

India, a megadiverse tropical country is grappling with the issue of biological invasions. As a signatory to the Convention on Biological Diversity, India is committed for managing its major biological invasions by 2020. Lack of prioritization of invasive species for control and management is the biggest hurdle for achieving this commitment. We reviewed 21 High Concern Invasive Species (HiCIS) across four major ecosystems (terrestrial mainland, island, freshwater, and marine) in India, utilizing the prioritization framework for understanding the existing knowledge and gaps. We reviewed the existing peer-reviewed and grey literature on HiCIS for information on their ecology, impacts, and management. Prioritization framework provided "priority scores" and "confidence scores" to each HiCIS, where priority score comprised of the species' ecology and its management lacunae. Confidence score represented the reliability of the priority score. We found that invasions on terrestrial mainland ecosystem in India are the most studied invasions followed by freshwater, island, and marine ecosystem. Priority score of a given HiCIS was positively correlated with its impacts on biodiversity (R = 0.63), physical environment (R = 0.70), and ecosystem services (R = 0.60). This correlation supports scientific focus on deleterious species. The study also indicates policies and guidelines in place for management of invasions as a part of a larger scheme or Legal Act, resulting in their obscurity to the managers, and hindering management of HiCIS. This quantitative synthesis provides a model framework for countries struggling with channelizing management efforts to an overwhelmingly large number of invasive species. [ABSTRACT FROM AUTHOR]

Human socio-cultural factors are recognized as fundamental drivers of urban ecological processes, but their effect on wildlife is still poorly known. In particular, human cultural aspects may differ substantially between the extensively studied urban settings of temperate regions and the poorly studied cities of the tropics, which may offer profoundly different niches for urban wildlife. Here, we report how the population levels of a scavenging raptor which breeds in the megacity of Delhi, the black kite Milvus migrans, depend on spatial variation in human subsidies, mainly in the form of philanthropic offerings of meat given for religious purposes. This tight connection with human culture, which generated the largest raptor concentration in the world, was modulated further by breeding-site availability. The latter constrained the level of resource-tracking by the kites and their potential ecosystem service, and could be used as a density-management tool. Similar ties between animal population densities, key anthropogenic resources and human beliefs may occur in thousands of cities all over the globe and may fit poorly with our current understanding of urban ecosystem functioning. For many urban animals, key resources are inextricably linked with human culture, an aspect that has been largely overlooked. [ABSTRACT FROM AUTHOR]

Increasing rate of bear-human conflict and declining black bear population remains a conservation paradox throughout its distributional range. Sound information on the patterns and dynamics of bear occurrence seems prerequisite towards addressing this issue, particularly in sub-tropical and temperate ecosystems. We aimed to understand the patterns of space-use and distribution of Asiatic black bears Ursus thibetanus in the Khangchendzonga Biosphere Reserve (BR) of Eastern Himalaya, and the factors influencing the same. We also modelled the distribution and extent of suitable habitats for bears in the Khangchendzonga landscape. We used sign surveys, trail monitorings, camera trapping, occupancy based space-use modelling and presence-only habitat suitability modelling using Ecological Niche Factor Analysis (ENFA). Almost all the black bear evidences (98%) were recorded from temperate and subalpine habitats. Broadleaved and coniferous forests were the best predictors for bear occurrence, and the percentage of acorn producing trees in temperate zone was the most important factor positively influencing the proportion of site utilization by bears during pre-hibernation periods. ENFA results indicate black bear as a ‘habitat specialist species’ and delineated only a small portion of the Biosphere Reserve (5.35%) as highly suitable for its occurrence. These highly suitable patches mostly occurred in the buffer zone outside the National Park boundary and were therefore, found as more susceptible to conflicts. Such patterns in habitat preference highlight the importance of local landscapes and demand for site specific conservation and management strategies for black bears in Khangchendzonga. [ABSTRACT FROM AUTHOR]

A thorough understanding of mechanisms of prey consumption by carnivores and the constraints on predation help us in evaluating the role of carnivores in an ecosystem. This is crucial in developing appropriate management strategies for their conservation and mitigating human-carnivore conflict. Current models on optimal foraging suggest that mammalian carnivores would profit most from killing the largest prey that they can subdue with minimal risk of injury to themselves., Wild carnivore diets are primarily estimated through analysis of their scats. Using extensive feeding experiments ( n = 68) on a wide size range (4·5-130 kg) of obligate carnivores - lion, leopard, jungle cat and domestic cat, we parameterize biomass models that best relate consumption to scat production. We evaluate additional constraints of gut fill, prey digestibility and carcass utilization on carnivory that were hereto not considered in optimal foraging studies., Our results show that patterns of consumption to scat production against prey size are similar and asymptotic, contrary to established linear models, across these carnivores after accounting for the effect of carnivore size. This asymptotic, allometric relationship allowed us to develop a generalized model: biomass consumed per collectable scat/predator weight = 0·033-0·025exp−4·284(prey weight/predator weight), which is applicable to all obligate carnivores to compute prey biomass consumed from scats. Our results also depict a relationship for prey digestibility which saturates at about 90% for prey larger than predator size. Carcass utilization declines exponentially with prey size. These mechanisms result in digestible biomass saturating at prey weights approximately equal to predator weight., Published literature on consumption by tropical carnivores that has relied on linear biomass models is substantially biased. We demonstrate the nature of these biases by correcting diets of tiger, lion and leopard in recent publications. Our analysis suggests that consumption of medium-sized prey was significantly underestimated, while large prey consumption was grossly overestimated in large carnivore diets to date. We highlight that additional constraints of prey digestibility and utilization combined with escalating handling time and risks of killing large prey make prey larger than the predator size unprofitable for obligate carnivores. [ABSTRACT FROM AUTHOR]

Antler cycles are convenient external signs indicating internal changes in reproductive status of male deer. Antler phenology of chital ( Axis axis) and sambar ( Rusa unicolor) were studied in a deciduous habitat of Mudumalai Tiger Reserve, Western Ghats, using vehicle transects for 2 successive years. Apparent breeding seasonality occurred with the majority of adult stags in hard antlers from May to mid October in chital (>87 %), and October to May in sambar (>68 %). Adult hard antler in chital correlated with mean group size, while sambar showed a weak correlation between adult hard antler and group size. Chitals prefer forming large groups at forest edges and open habitats while sambars prefer dense vegetation cover. Adult hard antlers in chital and sambar showed a weak relation to fawning since most adult females were in oestrus during the peak rutting season. Adult hard antlers in chital associated positively with rainfall and day length while sambar responded weakly to rainfall. We conclude that environmental variables determined species-specific mating strategies in the two deer species. [ABSTRACT FROM AUTHOR]

To understand the home range and resource selection of trans-located leopards, two male leopards were cap-tured from conflict areas and released in the Sariska Tiger Reserve, western India (March 2009-August 2010). Both the leopards were fitted with VHF radio-collar, and 148 locations were collected from the first leopard (SP1) and 268 locations from the second (SP2). Third-order resource selection function (resource selection of the individual animal within its home range) was estimated from trans-located leop-ards using generalized linear mixed effect model with data on vegetation types, elevation, encounter rate of prey species and presence of tiger. With 100% minimum convex polygon (MCP), the estimated home range of SP1 and SP2 was 84.3 and 63.2 km² respecti-vely. Both the leopards established their home ranges in and around the Sariska Tiger Reserve. The resource use of these trans-located leopards increased with increasing area of Zizyphus mixed forest and Acacia mixed forest, and decreased with increasing area of Anogeissus-dominated forest. Similarly, they selected habitats with higher encounter rate of wild pig and nilgai, and used less the habitats with high encounter rate of chital and common langur. Finally, it was obser-ved that the 'problem' leopards in this study showed significant positive selectivity to the available natural vegetation types and wild-prey abundance, rather than degraded habitats and domestic prey species. [ABSTRACT FROM AUTHOR]

Remote technologies are producing leapfrog advances in identifying the routes and connectivity of migratory species, which are still unknown for hundreds of taxa, especially Asian ones. Here, we used GPS-telemetry to uncover the migration routes and breeding areas of the massive population of migratory Black-eared kites wintering around the megacity of Delhi-India, which hosts the largest raptor concentration of the world. Kites migrated for 3300–4800 km along a narrow corridor, crossing the Himalayas at extremely high elevations (up to > 6500 m a.s.l.) by the K2 of the Karakoram Range and travelled long periods at elevations above 3500 m. They then crossed/circumvented the Taklamakan Desert and Tian Shan Range to reach their unknown breeding quarters at the intersection between Kazakhstan, Russia, China and Mongolia. Route configuration seemed to be shaped by dominant wind support and barrier avoidance. Wintering ranges were smaller than breeding ranges and concentrated around Delhi, likely in response to massive human food-subsidies. Our results illustrate that high-elevation crossings by soaring migrants may be more common than previously appreciated and suggest the delineation of a hitherto poorly-appreciated "Central Asian Flyway", which must funnel hundreds of thousands of migrants from central Asia into the Indian subcontinent via multiple modes of the Himalayan crossing. [ABSTRACT FROM AUTHOR]

Satellite imagery has been used to provide global and regional estimates of forest cover. Despite increased availability and accessibility of satellite data, approaches for detecting forest degradation have been limited. We produce a very-high resolution 3-meter (m) land cover dataset and develop a normalized index, the Bare Ground Index (BGI), to detect and map exposed bare ground within forests at 90 m resolution in central India. Tree cover and bare ground was identified from Planet Labs Very High-Resolution satellite data using a Random Forest classifier, resulting in a thematic land cover map with 83.00% overall accuracy (95% confidence interval: 61.25%-90.29%). The BGI is a ratio of bare ground to tree cover and was derived by aggregating the land cover. Results from field data indicate that the BGI serves as a proxy for intensity of forest use although open areas occur naturally. The BGI is an indicator of forest health and a baseline to monitor future changes to a tropical dry forest landscape at an unprecedented spatial scale., (© 2023. Springer Nature Limited.)

While human-driven biological invasions are rapidly spreading, finding scalable and effective control methods poses an unresolved challenge. Here, we assess whether megaherbivores-herbivores reaching ≥1,000 kg of body mass-offer a nature-based solution to plant invasions. Invasive plants are generally adapted to maximize vegetative growth. Megaherbivores, with broad dietary tolerances, could remove large biomass of established plants, facilitating new plant growth. We used a massive dataset obtained from 26,838 camera stations and 158,979 vegetation plots to assess the relationships between megaherbivores, native plants and alien plants across India (~121,330 km 2 ). We found a positive relationship between megaherbivore abundance and native plant richness and abundance, and a concomitant reduction in alien plant abundance. This relationship was strongest in protected areas with midproductive ecosystem and high megaherbivore density but it was lost in areas where thicket-forming alien plants predominated (>40% cover). By incorporating the role of ecosystem productivity, plants traits and densities of megaherbivores on megaherbivore-vegetation relationships, our study highlights a function of megaherbivores in controlling alien plant proliferation and facilitating diverse native plants in invaded ecosystems. The study shows great potential for megafauna-based trophic rewilding as a nature-based solution to counteract dominance of plant invasions., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Reintroduction of endangered species is an effective and increasingly important conservation strategy once threats have been addressed. The greater one-horned rhinoceros and swamp buffalo have declined through historic hunting and habitat loss. We identify and evaluate available habitat across their historic range (India, Nepal, and Bhutan) for reintroducing viable populations. We used Species Distribution Models in Maxent to identify potential habitats and evaluated model-identified sites through field visits, interviews of wildlife managers, literature, and population-habitat viability analysis. We prioritize sites based on size, quality, protection, management effectiveness, biotic pressures, and potential of conflict with communities. Our results suggest that populations greater than 50 for rhinoceros and 100 for buffalo were less susceptible to extinction, and could withstand some poaching, especially if supplemented or managed as a metapopulation. We note some reluctance by managers to reintroduce rhinoceros due to high costs associated with subsequent protection. Our analysis subsequently prioritised Corbett and Valmiki, for rhino reintroduction and transboundary complexes of Chitwan-Parsa-Valmiki and Dudhwa-Pilibhit-Shuklaphanta-Bardia for buffalo reintroductions. Establishing new safety-nets and supplementing existing populations of these megaherbivores would ensure their continued survival and harness their beneficial effect on ecosystems and conspecifics like pygmy hog, hispid hare, swamp deer, hog deer, and Bengal florican.

Populations of the Ganges river dolphin ( Platanista gangetica gangetica ) are endangered, with ~3500 individuals estimated worldwide. Threats to this precarious population is exacerbated by accidental entanglement and illegal hunting for oil, which is used in bait fisheries and traditional medicine. Alternatives to dolphin oil have been proposed and extensively promoted in India, to curb the immediate threat to dolphin populations. However, it is not known whether dolphins are still being poached for oil, despite the proposal of aforementioned alternatives. Herein, a molecular protocol to monitor the presence of Dolphin DNA, using species identification of DNA extracted from bait oils obtained from fishermen is presented. This is coupled with information from social surveys to understand the current status of use of dolphin oil. Results indicate that molecular tools provide an accurate technique for detecting the presence of dolphin DNA, and can be used by enforcement agencies to monitor and identify points of threat to dolphins. Social survey results indicate the preference of fishermen to continue the use of dolphin oil for bait, despite knowing the legal implications. It is found that alternate oils do not provide an effective solution to curb dolphin oil use, and only shifts the threats of endangerment from one species to another, in the long run. The ban of bait fishing, effective enforcement combined with monitoring through molecular tools, continued community engagement and livelihood skill development are the most viable solutions for a holistic conservation approach., (© 2020 The Author(s).)