Posts in category: Scientific_Papers

Authors: Bivek Gautam and Santosh Bhattarai

Paper link: pdf

Authors: Dol Raj Thanet, Saneer Lamichhane, Tirtha Bahadur Kshetri, Madhu Chaudhari, Santosh Rayamajhi, Thakur Silwal

Abstract: Human recreation increasingly influences wildlife behavior, yet spatial and temporal responses
are rarely studied together. We used the COVID-19 lockdown and pre-lockdown survey periods in Bardia National Park, Nepal, as a quasi-experiment to investigate how sudden relaxation in human recreation alters site use and diel activity patterns of predator–prey assemblage. Using camera trapping data, we analyzed camera stations that were in operation during both survey periods within an identical 48-day temporal window [24 March–10 May; pre-lockdown (2019) vs. lockdown (2020)]. Spatial responses were estimated using a two-season, multi-species hierarchical site use model, and temporal responses with kernel density overlap and a probability of diurnality. Site use increased during the lockdown for apex predators and several ungulate prey, especially tiger, wild boar, and nilgai, while chital showed little change, and others showed highly uncertain changes with credible intervals overlapping zero. Prey ungulates broadly reclaimed daylight: chital and barking deer shifted mean activity peaks 2–3 h later, hog deer shifted earlier with a marked reshaping of its activity curve, and sambar moved from nocturnal to
crepuscular peaks. Tiger activity changed little overall, though diurnal activity decreased. Yearspecific
functional responses to greenness (NDVI), elevation, and human disturbance were mostly similar across years but with higher predicted site use in 2020, indicating increased habitat permeability rather than changes in habitat selection. These patterns suggest that spatial and temporal responses are only partly aligned across species, so management strategies that protect both where and when wildlife can operate—for example, zoning away from key corridors and quiet hours around dawn and dusk—may be most effective in maintaining access to critical habitats and activity periods.

Keywords: Human disturbance, Site use, Multi-species occupancy model, Diurnality, Diel activity patterns, Predator-prey interactions

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Authors: Basant Subedi, Sandeep Oli, Chiranjeevi Khanal, Santosh Bhattarai

Abstract: We herein present a checklist of 28 species of snakes in 20 genera and seven families recorded as rescues or opportunistic sightings between July 2018 and December 2024 in Dang District, Lumbini Province, Nepal. Fifteen species are in the family Colubridae, five in the family Elapidae, two each in the families Erycidae, Natricidae, and Viperidae, and one each in the families Pythonidae and Typhlopidae. We provide photographic evidence of the Streaked Kukri Snake (Oligodon taeniolatus) from the Deukhuri Valley as a new record for Nepal and an additional 13 species were new records for Dang District. The major threats observed during the study period were forest fires, forest encroachment, construction activities, and intentional killing of snakes.

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Authors: Bivek Gautam, Santosh Bhattarai

Published in: FrogLog

Link: https://www.iucn-amphibians.org/wp-content/uploads/sites/4/2025/12/FrogLog-127-12th-December-2025.pdf

Authors: Santosh Bhattarai, Bivek Gautam, Chiranjibi Prasad Pokheral, Ram Chandra Kandel

Abstract: An updated checklist of amphibians and reptiles of Chitwan National Park and its buffer zone is presented, which is essential for conservation management decision-making as the area is experiencing frequent stochastic events in recent years. A total of 89 species is listed from Chitwan National Park including—20 frogs & toads, 42 snakes, 14 lizards, 11 turtles, and two crocodile species. The confirmed
record of Dudhwa Reed Frog Chirixalus dudhwaensis in Nepal is provided, and the occurrence of Eastern Bronze-back Tree Snake Dendrelaphis proarchos from Chitwan National Park, representing its westernmost known distribution in Nepal. In addition the presence of Hylarana tytleri and Sitana sivalensis is confirmed from Chitwan National Park. These findings contribute to filling critical knowledge gaps in species richness and offer updated insights into the taxonomy, natural history, and conservation status of herpetofauna in the park. Recent IUCN Red List mentions the geographic range of the Torrent Paha Frog Nanorana ercepeae from Chitwan National Park; based on the absence of verified records, we exclude it from updated checklist. We also suggest integrative taxonomic and ecological studies to uncover hidden diversity, and to inform evidence-based conservation strategies for amphibians and reptiles in Nepal.

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Authors: Santosh Bhattarai, Bivek Gautam, Bishal Prasad Neupane, Akshay Khandekar, Tejas Thackeray, Ishan Agarwal, Ashley R. Olson, Fiona Hogan, Wendy Wright

Journal: Zookeys

Abstract: Two new species of Cyrtodactylus from the khasiensis group are described using morphological characters supported by molecular analyses based on the mitochondrial ND2 gene. Cyrtodactylus makwanpurgadhiensis sp. nov. and C. chure sp. nov. from the Siwalik Mountains in central Nepal are at least 11.2% divergent from other Nepalese congeners and 16.7% from each other and can be distinguished by a combination of morphometric and meristic traits. The description of two new species from the Siwalik Mountains underscores the conservation significance of this region, a relatively young, dry, and geologically unstable range of the Himalayan orogen. Despite serving as a border between the lowland (Terai) and Himalayan range, it remains underrepresented in both biodiversity assessments and conservation planning in Nepal. Our findings suggest the need for a robust and targeted species research program and to prioritise this landscape for conservation actions.

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Authors: Santosh Bhattarai, Bivek Gautam, Bishal Prasad Neupane, Akshay Khandekar, Tejas Thackeray, Ishan Agarwal, Frank Tillack, Ashley R. Olson, Fiona Hogan, Wendy Wright

Abstract: We conduct a review of the known species of Cyrtodactylus from Nepal based on type and topotypical material, resulting in the synonymization of one species and description of three additional species from Central Nepal. The five species of Cyrtodactylus from Nepal are members of the Indo-Burma clade and are at least 11.7 % divergent from known congeners based on the mitochondrial ND2 gene. The results show that C. nepalensis and one of the new species are allied to the C. fasciolatus group while the other two new species and C. martinstolli are members of the mountain subclade within the khasiensis group. The new species can be readily distinguished from congeners in the Himalaya by a combination of body size, meristic characters including number of dorsal tubercle rows and mid ventral scales across the belly, the number and arrangement of pores in males and females, and subcaudal condition.

Journal: Zootaxa

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Authors: H. B. Katuwal, B. P. Bhattarai, S. Regmi, S. Bhandari, A. K. Ram, B. Aryal, K. Tamang, S. Kc, A. Nepali, D. Adhikari, S. Koirala, B. D. Baral, S. Devkota, R. Gautam, D. N. Mandal, J. L. Belant, H. P. Sharma, R.-C. Quan

Abstract: Large carnivores such as leopards (Panthera pardus) experience continuing threats from habitat loss and fragmentation, depletion of prey populations, and retaliatory killing following conflicts with humans. We aimed to identify factors affecting leopard occupancy and temporal overlap between leopards and tigers (P. tigris), their major prey, and human activities in the Parsa-Koshi Complex (PKC), Nepal. We deployed 154 cameras for 21 days each along wildlife trails throughout PKC during December 2022–March 2023. We found low leopard occupancy (0.17 ± 0.04) in PKC, with greater occupancy rates within protected areas, particularly in Parsa National Park and its buffer zone. Human (63.10 ± 23) and livestock (36.46 ± 102) detections were higher across the PKC. Leopard occupancy was positively associated with the presence of tigers and prey. Temporal overlap was moderately high between leopards and tigers, as well as between leopards and their prey. Our research suggests that coexistence between leopards and tigers is likely largely facilitated by higher prey availability, which may reduce competition. Further, we demonstrate that maintaining forest cohesion can improve habitat for leopards. Intensifying use of agricultural areas could reduce forest fragmentation and increase leopard habitat overall, in turn reducing leopard depredation of livestock and improving leopard-human co-existence and conservation.

DOI: https://doi.org/10.1111/jzo.13251

Journal: Journal of Zoology

Paper link: https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/jzo.13251

Authors: Dipendra Adhikari, Jagan Nath Adhikari, Janak Raj Khatiwada, Bishnu Prasad Bhattarai, Subarna Ghimire and Deepak Rijal

Abstract: Wetlands support around 27% of birds in Nepal, however, there is a paucity of information about bird diversity and the wetland habitat of Western Chure Landscape Nepal. The “point count” method along transects was carried out to evaluate the species composition and habitat associations of birds. A total of 2,532 individuals representing 152 species (winter: N = 140 and summer: N = 91) from 19 orders and 51 families were reported from Jhilmila Lake and its surrounding area. The number of birds was reported to be significantly higher during winter than in the summer season. The species diversity was also higher in winter (Shannon’s index (H) = 4.38, Fisher’s alpha = 30.67) than in summer (H = 4.21, Fisher’s alpha = 34.69) as this area is surrounded by old-growth forest that provides available habitats for forest, grassland- and wetland-dwelling birds. This lake is an example of a wetland present in the Chure area that plays an important role in the conservation of biodiversity along with birds. Hence, we recommend its detailed study in terms of biodiversity and water quality.

Journal: Ornis Hungarica

Doi: https://doi.org/10.2478/orhu-2023-0002

Paper link: pdf

Authors: Binod Bhattarai, Dipendra Adhikari, Jagan Nath Adhikari,
and Bishnu Prasad Bhattarai

Abstract: Invasive alien species play a major role in biodiversity decline. We studied the impacts of invasive alien plant species (IAPS) on bird assemblages and their habitats in Jalthal Forest, a biogeographically unique lowland remnant forest in eastern Nepal. We surveyed birds by point counts and quantified environmental variables at 89 sites. Observations of 1,373 individuals of 86 species showed that species richness was the highest in wooded grasslands and floodplains and lowest in sal forests invaded by IAPS, whereas abundance was highest in IAPS invaded forests. Abundance and richness decreased with increasing cover of IAPS, shrub cover and distance to water. The abundance and richness of every feeding guild except omnivores were negatively correlated with IAPS cover. Our results increase our understanding of the impacts of IAPS on birds and clearly indicate the need of controlling IAPS in Jalthal Forest, and thus, are valuable for forest management and biodiversity conservation.

Journal: ORNIS HUNGARICA

Paper link: https://sciendo.com/article/10.2478/orhu-2024-0019