Geology topics

Chiranjibi Prasad Pokheral

Publications and source records attributed to Chiranjibi Prasad Pokheral.

2 recordsLinked to original sources

USGS2025

If you build it, will they come? Assessing the response of tiger populations to elevated conservation efforts in lowland Nepal

Thirteen countries within the distributional range of tigers adopted the St. Petersburg Declaration in 2010, committing to double their tiger populations by 2022. As a signatory to this document, Nepal elevated its tiger conservation efforts soon after the declaration was adopted. Using capture-mark-recapture (CMR) analyses of tiger survey data (2013–2022), we assessed the response of tiger populations to enhanced conservation measures in Banke and Bardia national parks (NP) in western lowland of Nepal. In Bardia NP, estimated tiger numbers increased from 49 in 2013 to 122 in 2022, and estimated population density increased from 3.39 in 2013 to 8.47 tigers/100 km 2 in 2022). Female survival rate was consistently higher than male, with 87.06 % during 2013–2018 and 89.08 % during 2018–2022, compared to 72.9 % and 76.6 % for males in the respective periods. Additionally, the female population grew at a faster rate (6–7 % per year vs. ∼ 2 % per year for males). In Banke NP, tiger abundance increased from 3 to 22 between 2013 and 2022, and population density increased from 0.34 to 2.42/100 km 2 over the same period. The remarkable 7-fold increase in tiger abundance within the Banke NP was facilitated by high male and female survival rates (≥ 90 % per year), as well as high recruitment rates (0.27 individual −1 year −1 ) from 2013 to 2018, leading to a robust (18–20 %) annual population growth rate. Tigers were recolonizing Banke NP at the beginning of this study, and the area offered ample space and a recovering prey base. This facilitated the recruitment of dispersers from the larger population in Bardia NP and allowed survival to be high by eliminating mortality due to density-dependent intra-specific aggression. Our results not only suggest that Nepal has met or exceeded its commitment to the St. Petersburg Declaration in Banke and Bardia NPs, but they highlight the ability of certain tiger populations to respond quickly and positively to enhanced conservation measures given suitable habitat and a healthy prey base.

Banke National Park, Bardia National Park↗

USGS2017

Using interviews and biological sign surveys to infer seasonal use of forested and agricultural portions of a human-dominated landscape by Asian elephants in Nepal

Understanding how wide-ranging animals use landscapes in which human use is highly heterogeneous is important for determining patterns of human–wildlife conflict and designing mitigation strategies. Here, we show how biological sign surveys in forested components of a human-dominated landscape can be combined with human interviews in agricultural portions of a landscape to provide a full picture of seasonal use of different landscape components by wide-ranging animals and resulting human–wildlife conflict. We selected Asian elephants ( Elephas maximus ) in Nepal to illustrate this approach. Asian elephants are threatened throughout their geographic range, and there are large gaps in our understanding of their landscape-scale habitat use. We identified all potential elephant habitat in Nepal and divided the potential habitat into sampling units based on a 10 km by 10 km grid. Forested areas within grids were surveyed for signs of elephant use, and local villagers were interviewed regarding elephant use of agricultural areas and instances of conflict. Data were analyzed using single-season and multi-season (dynamic) occupancy models. A single-season occupancy model applied to data from 139 partially or wholly forested grid cells estimated that 0.57 of grid cells were used by elephants. Dynamic occupancy models fit to data from interviews across 158 grid cells estimated that monthly use of non-forested, human-dominated areas over the preceding year varied between 0.43 and 0.82 with a minimum in February and maximum in October. Seasonal patterns of crop raiding by elephants coincided with monthly elephant use of human-dominated areas, and serious instances of human–wildlife conflict were common. Efforts to mitigate human–elephant conflict in Nepal are likely to be most effective if they are concentrated during August through December when elephant use of human-dominated landscapes and human–elephant conflict are most common.

Ethology Ecology and Evolution↗