Abishek Harihar | Panthera Colombia (original) (raw)

Papers by Abishek Harihar

Note: Model rankings are based on Akaike’s Information Criterion (AIC).a<p&... more Note: Model rankings are based on Akaike’s Information Criterion (AIC).aCovariates used to model detection probability were Block (B), Wild prey index (WildP), Principal prey index (PrincipP), Disturbance (Dist) and proportional habitat per cell (Hab).bIn all models the probability of detection () was modelled as ‘B + Substrate’ based on model selection results presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0040105#pone-0040105-t001" target="_blank">Table 1</a>. Segment-level occupancy parameters ( and ) were modelled on ‘B’ (Block). ‘×’ denotes covariates were modelled as an interaction.</p

Environment and Natural Resources Journal

Tigers (Panthera tigris) have disappeared from over 90% of their historical range, and extant pop... more Tigers (Panthera tigris) have disappeared from over 90% of their historical range, and extant populations face habitat loss, direct poaching, and prey depletion in otherwise suitable habitats. In Thailand, tiger numbers continue to decline due to prey depletion, yet a few strongholds remain. Recently, tigers have been detected in the Southern Western Forest Complex (sWEFCOM), following intensification of conservation efforts. However, there is still a lack of primary data on the status of tigers and their prey in the sWEFCOM. To fill this knowledge gap, we conducted camera trapping surveys between 2019 and 2020 in Khuean Srinagarindra National Park (KSR) and Salakphra Wildlife Sanctuary (SLP). Located near a tiger source population in Thungyai Naresuan and Huai Kha Khaeng, these areas are potential areas for tiger recovery. In particular, our study assessed the status of prey, a prerequisite to the persistence and recovery of tigers. Based on relative abundance indices, time overlap...

Frontiers in Ecology and Evolution

Unplanned land-use change surrounding protected areas (PAs) can lead to degradation and fragmenta... more Unplanned land-use change surrounding protected areas (PAs) can lead to degradation and fragmentation of wildlife habitats, thereby placing tremendous pressure on PAs especially in tropical countries. Incentivizing the expansion of habitats beyond PAs will not only benefit wildlife but also has the potential to create livelihood opportunities for marginalized communities living adjacent to PAs. Our study explored landowners’ willingness to participate in an incentive-based, wildlife-friendly land-use program using a discrete choice modeling approach. We surveyed 699 landowners living in 287 villages within a five-kilometer buffer around Nagarahole and Bandipur National Parks in India. We found that landowners preferred wildlife-friendly land-use over their ongoing farming practices. Landowners preferred short-term programs, requiring enrolling smaller parcels of land for wildlife-friendly land-use, and offering higher payment amounts. Landowners with larger landholdings, a longer hi...

Interview data on human-tiger interactions in the Sumatran study landscape used in publication of... more Interview data on human-tiger interactions in the Sumatran study landscape used in publication of McKay et. al in Plos 1.

Herpetological Journal, 2010

Melanochelys tricarinata is a poorly known terrestrial South Asian geoemydid turtle with a small ... more Melanochelys tricarinata is a poorly known terrestrial South Asian geoemydid turtle with a small distributional range. From 2002 to 2008, we monitored a population of the species in the Doon valley of northern India, and obtained information on its population characteristics, general activity pattern and diet. In total, 120 individual turtles were captured (47 males, 37 females and 36 unsexedjuveniles and hatchlings). Turtles were captured mainly during the rainy months (94.4%), and captures were significantly correlated with periods of high rainfall. The overall adult sex ratio was unbiased. The larger body size was, however, biased towards males. With an average carapace length of 154 mm (range 127-175 mm) and a weight of 461.5 g (range 280.0―621.1 g), males were larger than females, who had an average carapace length of 138 mm (range 117-151 mm) and an average weight of 382.5 g (range 240.0―511.1 g). No increase in carapace length in either male or female turtles was observed aft...

Early naturalists recorded descriptive accounts of tigers in tropical Asia during the past two to... more Early naturalists recorded descriptive accounts of tigers in tropical Asia during the past two to three centuries (Karanth 2001).

Conservation and management planning of tigers and prey species requires basic information on the... more Conservation and management planning of tigers and prey species requires basic information on the spatial distribution at regional and landscape levels, at an appropriate scale (Karanth and Nichols 2000).

Conservation Letters, 2021

Armed conflicts are a pervasive global threat, but their implications for wildlife conservation r... more Armed conflicts are a pervasive global threat, but their implications for wildlife conservation remain unclear. Using a 30-year spatial dataset of armed conflicts in conjunction with species range maps, we found that conflicts during 1989-2018 occurred within at least 4291 (78%) and 9056 (85%) terrestrial mammal and bird species ranges, respectively. For 4% overall and 5-7% of threatened species, conflicts within ranges have been both widespread (≥50% of range) and frequent (≥15 years). Further, an examination of International Union for Conservation of Nature Red List assessments revealed that ranges overlap with armed conflicts is associated with declining population trends of threatened species and distinct species threat portfolios in which hunting and habitat loss and degradation are more prominent. Our findings call for greater recognition and understanding of direct and indirect threats from armed conflicts in species conservation assessments and underscore the importance of addressing conflict resiliency in conservation plans for a wide suite of species.

Animal Conservation, 2020

Inferring the mechanisms that facilitate sympatry amongst large mammalian carnivores in anthropog... more Inferring the mechanisms that facilitate sympatry amongst large mammalian carnivores in anthropogenically altered habitats is critical if conservation initiatives aimed to recover populations are to be effective. In this study, we assessed the utilization of space, time and prey resources by tigers Panthera tigris, leopards P. pardus and dholes Cuon alpinus in Manas National Park (MNP), Indiaa site where prey densities are not limiting, yet anthropogenic influences alter the spatial and temporal behaviour of prey. We use photographic capture data and predator scats collected over three sampling years (2014-15, 2015-16 and 2016-17) to assess patterns of (a) spatial use using a multispecies species occupancy framework, (b) time-activity patterns and overlap between predators and prey using nonparametric circular kernel-density functions, (c) fine-scale spatio-temporal behaviour by comparing time-to-encounters of subsequent events and (d) predator diets by analysing prey remains in predator scats. Our results highlight that the predators segregate through fine-scale spatio-temporal avoidance rather than displaying population-level changes in space-use, activity patterns or food habits. Overlap in space-use between tigers and leopards was high and time-activity patterns of the predators closely matched those of prey, suggesting that predators likely maximize resource acquisition in this prey-rich environment. Ungulate prey dominated the diet of predators, resulting in the high dietary overlap. From our results, we infer patterns of sympatry among large carnivores in the face of anthropogenic influences and highlight the need to understand interspecific interactions within a community before initiating conservation actions aimed at recovering these endangered species.

Biological Conservation, 2020

Background: Right hepatectomy (RH) is the most common type of major hepatectomy and can be achiev... more Background: Right hepatectomy (RH) is the most common type of major hepatectomy and can be achieved without portal triad clamping (PTC) in non-cirrhotic liver. The present study reviews our standardized policy of performing RH without systematic PTC. Methods: One hundred and eighty-one consecutive RH were performed in non-cirrhotic patients, with division of the right afferent and efferent blood vessels prior to transection, without systematically using PTC. Prospectively collected data were analysed, focusing on the following endpoints: need for salvage PTC, ischaemic time, blood loss and post-operative outcome. Results: Extra-hepatic division of the right hepatic vessels was feasible in all patients, but was ineffective in 48 patients (26.5%) who required salvage PTC during transection. In those patients, the median ischaemic time was 20 min. The median blood loss was 500 ml (50-3000). Six patients (3.3%) experienced post-operative liver failure. Overall morbidity, severe morbidity and mortality were 42%, 12.1% and 1.6%, respectively, with peri-operative transfusion rate (16.6%) being the only factor associated with morbidity. Discussion: By performing RH with extra-hepatic vascular division prior to transection, PTC can be safely avoided in the majority of patients.

Melanism is a form of pigmentation polymorphism where individuals have darker colouration than wh... more Melanism is a form of pigmentation polymorphism where individuals have darker colouration than what is considered the “wild” phenotype. In the case of leopards, Panthera pardus, melanism occurs at higher frequencies amongst populations in tropical and subtropical moist forests of south and southeast Asia, presenting a unique challenge in estimating and monitoring these populations. Unlike the wild phenotype that is readily recognizable by its rosette patterns, melanism results in individuals being unidentifiable or ‘unmarked’ through photographic captures obtained using white flash cameras. Spatial mark-resight (SMR) models that require only a subset of the population to be ‘marked’ offer the opportunity to estimate population density. In this study, we present an application of SMR models to estimate leopard densities using camera trap survey data from three sampling years at Manas National Park (MNP), India. By using an SMR model that allowed us to include captures of unidentified...

Biological Conservation, 2020

Large carnivores have experienced significant global range contractions and recovering their popu... more Large carnivores have experienced significant global range contractions and recovering their populations is often contingent on increasing prey abundances. In Manas National Park (MNP), following nearly two decades of ethnopolitical conflict, studies document that populations of both prey and predators were depressed. Here we assess the status of wild ungulates in a section of MNP (Bansbari-Bhuyanpara) that has remained conflict-free for over a decade. For seven ungulate species, we estimate species-specific densities using distance-based sampling, assess species-specific space-use patterns in relation to habitat variables within an occupancy framework and examine patterns of temporal activity in relation to times when people access the park for resources. Further, by comparing temporal activity patterns of ungulates between MNP, a site where local communities access the park for resources, and Kaziranga National Park, where human use of the park is minimal, we examine if species activity is altered in response to human presence. We estimate that currently Bansbari-Bhuyanpara ranges of MNP support 42.66 (34.16-51.16) individual ungulates/km 2. Our results highlight that current patterns of human access within the park affect both spatial and temporal behaviour of these species. Although we estimate a relatively high recovery potential for tigers in MNP given current prey densities, we suggest that further ungulate population recoveries could be supported in the park. With several ungulate species experiencing range-wide declines, efforts to minimize non-lethal human disturbances on these species also need to be considered to ensure that predator-prey systems remain intact.

Biological Conservation, 2020

Spatially explicit capture-recapture analysis is widely utilized for estimating densities of tige... more Spatially explicit capture-recapture analysis is widely utilized for estimating densities of tigers (Panthera tigris). However, developing a robust study design capable of meeting assumptions and achieving study objectives may be difficult, particularly for low-density populations. Study design decisions for such fieldwork can be aided by simulations. Our goal was to (1) use simulations to investigate and evaluate study design and (2) generate a reliable estimate of density for a population of tigers in Thailand's Dong Phayayen-Khao Yai forest complex. Scenarios were parameterized with a range of potential density estimates (D) and detection function parameters (g 0 and σ). We designed a field-based trap configuration identified and compared it with simulated performance of a regular trapping array, over 45-day and 60-day sampling occasions. We compared simulation results (i.e. number of individuals [n], detections [ndet], relative standard error [RSE] and relative bias [RB]) and identified that the non-regular trapping array deployed for 60 sampling days would generate reliable density estimates. Our survey produced a density estimate of 0.63 ± SE0.22; (0.32-1.21) tigers per 100 km 2 , from a model incorporating variation in sex for g 0 and σ, and a population estimate of 20 (14-33). Simulations closely reflected actual results under the null model. Our survey design performed reasonably well, generating a sufficient number of detections and individuals to estimate density of a globally important tiger population. Our results suggest simulations and use of non-regular trap arrays may be beneficial for areas with low species density in which generating sufficient detections is particularly challenging.

Journal of Threatened Taxa, 2018

Information on the presence and distribution of species is crucial for conservation planning and... more Information on the presence and distribution of species is crucial for conservation planning and management within a region. Documentation of species assemblages in Manas National Park (MNP) in the aftermath of conflict is critical for informed conservation interventions. For nearly two decades (1990–2010), conservation efforts in MNP were compromised by ethno−political conflict. We conducted camera trapping surveys of terrestrial mammals across three administrative forest ranges (Panbari, Bansbari and Bhuyanpara) of MNP in 2017. A systematic survey with 118 trap locations accumulated data over 6,173 trap-days. We obtained 21,926 photographs of mammals belonging to 13 families and 25 species, of which 13 are threatened. We calculated photographic capture rate index (PCRI) using independent events. Trap specific PCRI’s were used to map the spatial variation in capture rates. We observed variation in capture rate between Bansbari-Bhuyanpara where conflict ended in 2003 and ha...

PLOS ONE, 2018

Religious beliefs and spiritual connections to biodiversity have the potential to reduce animosit... more Religious beliefs and spiritual connections to biodiversity have the potential to reduce animosity towards wildlife that might otherwise present a real or perceived threat to local people. Understanding this social dynamic can therefore be important for formulating locally-appropriate species-specific conservation strategies. Using semi-structured interviews which incorporated human-tiger conflict scenarios, we investigated how beliefs towards tigers varied between ethnic groups living around a large protected area that is home to the largest tiger population in Sumatra. We gathered this information to determine the degree to which cultural tolerance may contribute to the survival of the tiger in the Kerinci Seblat landscape, Indonesia. From 154 interviewees, 133 respondents came from three main ethnic groups, Minangkabau, Kerincinese and Melayu. The majority (73.5%) of Minangkabau interviewees cited that their ethnic group had customary laws regarding tigers, as did 52% of Melayu and 44% of Kerincinese. Irrespective of ethnicity, most participants did not perceive there to be a connection between Islam and tigers. All participants acknowledged the existence of zoological tigers and two groups (Minangkabau and Kerincinese) held a strong common belief that different types of spirit tigers also existed. From presenting different human-tiger conflict scenarios, with varying levels of severity towards livestock or human life, an unprovoked tiger attack in the village elicited the most calls for the tiger to be killed. Yet, if a village or family member was killed by a tiger whilst hunting in the forest then most respondents across all ethnic groups said to do nothing. The frequency of this response increased if a tiger killed someone in the village who had committed adultery, reflecting beliefs associated with the role of the tiger as an enforcer of moral rule. Our study highlights the importance of consulting with local communities who live in close proximity to large and potentially dangerous carnivores when developing conflict mitigation strategies, which hitherto has not been the case in Sumatra.

Biological Conservation, 2018

Illegal wildlife trade represents a major threat to biodiversity. Recent wildlife consumption tre... more Illegal wildlife trade represents a major threat to biodiversity. Recent wildlife consumption trends across Asia have shown shifts in preference towards new species, such as Sunda pangolin, and increased volumes of consumption for longer-traded species, such as tiger. These trends are widely thought to be a result of the higher levels of wealth generated from the impressive economic growth experienced across Asia. This raises important questions regarding the role that economic growth plays as a driver of poaching on source populations of highlyprized species. As a first step to answering these, we investigate trade dynamics related to the poaching of tigers and their principal prey using a long-term biological and economic data set. The fluctuating poaching patterns recorded for tiger prey, which are locally consumed for their meat, showed no association with rising domestic beef prices, the most likely substitutable protein source. However for tiger, annual poaching rates were positively and significantly correlated with changes in local tiger skin prices that, in turn, were closely correlated with annual GDP changes in the key consumer countries. Our preliminary analysis raises further questions around the causal pathways through which rising affluence and extinction risk are linked; a question that should be posed for a wide set of species. Thus, the strong regional leadership that has enabled high economic growth across Asia and lifted hundreds of millions of people out of poverty should now be urgently directed to tackling illegal wildlife trade and, as a priority, to closing domestic and international trafficking routes.

Environment and Natural Resources Journal

Frontiers in Ecology and Evolution

Herpetological Journal, 2010

Conservation Letters, 2021

Animal Conservation, 2020

Biological Conservation, 2020

Journal of Threatened Taxa, 2018

PLOS ONE, 2018

Biological Conservation, 2018