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Abstract Invasive alien plant species (IAPS) pose a serious threat to overall plant biodiversity across the globe. Nepal's national parks and protected areas are not devoid of the impact of IAPS. Unfortunately, there is a substantial gap in knowledge regarding the extent and impact of invasion in protected areas of Nepal. This study assessed the impact of invasive alien plant species on the resident plant species of the Koshi Tapu wildlife reserve. After a preliminary field observation, we selected five major IAPS in the area, Mesosphaerum suaveolens, Chromolaena odorata, Ipomoea carnea, Lantana camara, and Mikania micrantha for this study. Ten pairs of adjacent plots sized 4 m × 4 m were surveyed for each invasive species, comprising diverse vegetation types. Each pair consisted of one “invaded plot” where the invasive species was dominant with cover greater than 50%, and another “uninvaded plot” laid out in an adjacent area with similar site conditions but without the invasive species. We calculated the Sørensen Index of Similarity for each paired plot. Wilcoxon rank‐sum test was employed to compare ecological parameters between invaded and uninvaded plots for various plant species. Similarly, the difference in impact between each of the five invasive species was assessed using the Kruskal–Wallis test. Species richness varied significantly between invaded and uninvaded plots for C. odorata and I. carnea. The most significant impact on species composition of invaded communities (39.6%) was observed for C. odorata. The cover of the other dominant species varied significantly between invaded and uninvaded plots for all five species studied. The Kruskal–Wallis test showed no significant difference in the impact caused by the five studied invasive species on Species richness, Shannon–Wiener diversity index, species evenness, and height of dominant species. However, a significant difference was observed between the impacts of five studied invasive species and the cover of other dominant species. The crown cover of dominant species decreased much more in the invaded plots of L. camara and M. micrantha than in other species. Specialized management efforts are required to control highly invasive species, such as C. odorata and I. carnea, alongside proactive measures to prevent further spread in ecologically sensitive areas.

The Chure region, among the world's youngest mountains, stands out as highly susceptible to natural calamities, particularly forest fires. The region has consistently experienced forest fire incidents, resulting in the degradation of valuable natural and anthropogenic resources. Despite its vulnerability, there have been limited studies to understand the relationship of various causative factors for the recurring fire problem. Hence, to comprehend the influencing factors for the recurring forest fire problem and its extent, we utilized generalized linear modeling under binary logistic regression to combine the dependent variable of satellite detected fire points and various independent variables. We conducted a variance inflation factor (VIF) test and correlation matrix to identify the 14 suitable variables for the study. The analysis revealed that forest fires occurred mostly during the three pre-monsoon periods and had a significant positive relation with the area under forest, rangeland, bare-grounds, and Normalized Difference Vegetation Index (NDVI) (P

Livestock depredation by leopards is a pervasive issue across many Asian and African range countries, particularly in and around protected areas. Developing effective conflict mitigation strategies requires understanding the landscape features influencing livestock depredation. In this study, we investigated predictors associated with livestock depredation by leopards using 274 cases of leopard attacks on livestock that occurred between 2017 and 2020 in the Annapurna Conservation Area, Nepal. We also examined how livestock predation by leopards varied depending on the species, season, and time. A generalized linear model with binary logistic regression was used to test the statistical significance of variables associated with the presence and absence of conflict sites. The results revealed that the area of forest, agricultural land, length of rivers, slope, proximity to settlements and protected areas, and elevation significantly predicted the probability of leopard attacks on livestock. We also observed a significant increase in the incidence of leopard predation on livestock with decreasing slopes and rising elevations. The areas near human settlements and the protected areas faced a higher risk of leopard predation. The incidence of leopard predation on livestock varied significantly depending on the livestock species, season, and time. Goats were the most highly predated livestock, followed by sheep, cow/ox, and buffalo. A total of 289.11 km2 (or around 5% of the research area) was deemed to be at high risk for leopard predation on livestock. This study’s comprehensive understanding of human-leopard conflicts provides valuable insights for planning and implementing measures to reduce damage caused by leopard populations throughout their range.

Endemic to India and Nepal, the swamp deer (Rucervus duvaucelii) is crucial for restoring and sustaining populations of top predators like tigers. Despite recent signs of species recovery in protected areas, the species remains vulnerable to extinction due to increasing anthropogenic activities. Information on factors influencing the occurrence of swamp deer is essential to formulate suitable management plans that can help to maintain their viable population and protect their habitats. We recorded swamp deer presence via direct sightings and indirect signs (pellets and footprints) through line transect surveys. Two ecological drivers i.e., habitat variables and disturbance variables that included eleven predictor variables were measured in the field where swamp deer was present (“used plots”) and absent (“habitat availability plot”). Binary logistic regression was used to analyze the factors associated with the probability of detecting the swamp deer. The model's outcomes showed that an increase in road/path/fireline distance and settlement distance, mixed forest habitat, and depth of leaf litter were positively correlated with the probability of locating swamp deer, while the other significant predictor variables (canopy cover, distance from water source, and presence of predator) had inverse relationships. In summary, our study has provided crucial insights into the factors influencing the presence of swamp deer in their habitat. These findings are useful for local governments and protected area authorities by providing fine-scale field-based scientific information, that can benefit swamp deer and its habitat. We also recommend similar studies in species range locations considering other influencing factors such as season, climate, interaction with other herbivore species, and predators that might affect the habitat use of swamp deer.

The Chure Hills, already vulnerable due to their fragile nature, face increased landslide risk, prompting the need for reliable susceptibility assessment. This study uses Poisson regression modeling to assess landslide susceptibility in two highly susceptible districts of the Chure region. Variance inflation factor (VIF) tests were conducted to ensure robustness, indicating no multicollinearity among the variables. Subsequently, Poisson regression analysis identified eight significant variables, among which geology, lineament density, elevation, relief, slope, rainfall, solar radiance, and land cover types emerged as important factors associated with landslide count. The analysis revealed that higher lineament density and slope were associated with lower landslide counts, indicating potential stabilizing geological and topographical influences. The categorical variable, namely geology, revealed that middle Siwalik, upper Siwalik, and quaternary geological formations were associated with lower landslide counts than lower Siwalik. Land cover types, including areas under forest, shrubland, grassland, agricultural land, water bodies, and bare ground, had a substantial significant positive association with landslide count. The generated susceptibility map that exhibited a substantial portion (23.32% in Dang and 5.22% in Surkhet) of the study area fell within the very-high-susceptibility categories, indicating pronounced landslide susceptibility in the Dang and Surkhet districts of the Chure hills. This study offers valuable insights into landslide vulnerability in the Chure region, serving as a foundation for informed decision-making, disaster risk reduction strategies, and sustainable land-use and developmental policy planning.

Mugger crocodile is found in various locations of Nepal, ranging from Eastern to Western lowlands, and is also a resident crocodilian of the Koshi Tappu Wildlife Reserve (KTWR). Fewer studies have been carried out on the status and distribution of this crocodilian with limited information on its habitat characteristics. This study sets forth to highlight the population status, distribution and habitat use by mugger crocodile in and around KTWR. Detailed surveys were conducted in the rivers, natural and private ponds of the KTWR in December 2020. Every 500 m along the survey transects, habitat characteristics were recorded in each habitat station as part of the habitat survey. The dependent variables were presence or absence of mugger crocodile in each habitat station. Meanwhile, the independent variables included habitat predictors such as; water depth, slope, elevation, distance to roads, distance to settlements, bank substrate, and human disturbance. Generalized Linear Model under binary logistic regression was employed to test variables associated with presence and absence of muggers for statistical significance. The population survey of the muggers was assessed by day counts either using dugout canoe or walking along transects. During the research period, 35 individuals of muggers were recorded. The probability of mugger sighting augmented with increased slope and depth. 34 muggers (97.14 %) were basking, while 1 (2.85%) were seen swimming out of the total muggers detected. In private and public ponds, 22 muggers were sighted, while 13 were sighted in the main Koshi river, its branches, and the Moriya river. Sixteen muggers (45.71 %) were sighted within the reserve, while the remaining 19 muggers (54.28 %) were sighted in the buffer-zone areas. The probability of mugger sighting varied considerably with regard to slope and water depth among the seven habitat predictors examined. In lieu of prevailing fishing pressure in the river systems of the KTWR and easy availability of prey species for muggers in private fishponds; the muggers are likely use private fishponds more frequently. In order to subdue the muggers inside the KTWR, the reserve authority has a vital role for proper habitat management decisions and regulation of fishing activities.

Mugger crocodile is a keystone species of slow flowing fresh water ecosystem. Few studies regarding status and distribution of Vulnerable Mugger have been conducted in Nepal. However, studies on ecology and other aspects of the species are limited. The goal of this study was to determine the Mugger crocodile's population status, habitat occupancy, and conservation threats in the Ghodaghodi lake complex, located in the western lowlands of Nepal. A detailed survey was conducted on 18 lakes of the lake complex in February, 2021. The population status of the Mugger was surveyed by walking along the entire boundary line of each lake. For habitat survey, perimeter of all the lakes of the complex was divided into the number of stations spaced at 500 m intervals. Habitat factors associated with the presence and absence of the Mugger were analyzed using Generalized Linear Model under binary logistic regression and likelihood ratio test was performed to test predictors for statistical significance. During the survey, 26 muggers were recorded. The probability of sighting Mugger in the lake complex was significantly differ by distance to settlement, distance to river, and human disturbances, among the nine habitat variables examined. Similarly, habitat modification and illegal fishing were ranked as most severe threats to Mugger crocodile in the lake complex. The concerned authorities, responsible for managing the lake complex shall pay attention on controlling the major identified threats like habitat modification, illegal fishing, unmanaged infrastructure development, and pollution in the lake complex in order to support future conservation of Vulnerable Mugger population in the area. Furthermore, a detailed and extensive study is suggested to investigate the movement of Muggers between different lakes of the complex as well as from Ghodaghodi lake complex to the nearby rivers during breeding season in order to support effective planning and execution of habitat management activities of this Vulnerable species.