Factors affecting the occupancy of Chinese pangolins (Manis pentadactyla) suggest a highly specialized ecological niche

Abstract

The Chinese pangolin is a critically endangered and biologically unique species, yet information on its status, distribution, and habitat preferences is still scarce in Nepal, which limits effective conservation action. This study identified the current burrow density status, distribution pattern, and important habitat parameters associated with Chinese pangolin distribution in Nepal through opportunistic field surveys. Fifty‐four belt transects were examined for the presence of pangolin burrows. For each active burrow (burrow with freshly dug soil, footprints, and scat near the entrance) and old burrow (burrow with compacted soil, presence of dead leaves, and spider web in the entrance), we recorded the geographic coordinates and assessed data on 11 habitat parameters that included elevation, aspect, slope, canopy cover, ground cover, presence or absence of ant and termite colonies, habitat type, soil type, and distances to the nearest water source, road, and settlement. A total of 141 active burrows and 430 old burrows were recorded with an overall clumped distribution {}()S2/a=2.188$$ \left\{\left({S}^2/a\right)=2.188\right\} $$. Active burrow density was estimated to be 1.04 burrows/ha. Of the 11 habitat parameters predicted to influence the probability of encountering pangolin burrows, all parameters were significant except elevation. More than 92% of the burrows were found at elevations between 450 and 750 m and facing either the SE or NW aspect. Similarly, about 90% of the burrows were distributed in areas having slopes between 0% and 30% with moderate to high canopy and ground cover, and located close to water sources, roads, and settlements. Additionally, they strongly preferred forest habitats (with Shorea robusta, Castanopsis indica, Schima wallichii, Clerodendron infortunatum, and Nephrolepis auriculata as the dominant vegetation), areas with red soil, and areas located near ant and termite colonies. Although the study area currently provides suitable habitat for Chinese pangolins, it is slowly being degraded due to increasing rates of forest degradation. Conservation efforts should be increased in order to protect this critically endangered species and their preferred habitats. Finally, our findings reveal the preferred habitat characteristics of Chinese pangolins, which could be instrumental for policy makers and forest managers in making conservation plans for Chinese pangolins.

Habitat preference and distribution of Chinese pangolin and people’s attitude to its conservation in Gorkha District, Nepal

“…This study revealed that pangolins are strongly associated with moderate canopy cover, which is in accordance with the results of Bhandari and Chalise (2014), Dorji et al (2020), andDhami et al (2023). A possible reason for this might be that soils below moderate canopy cover are dry and consist of relatively undecomposed leaf litter and a greater amount of dead twigs and branches (Bhandari and Chalise, 2014), whereas the soil where the crown cover is above 60% is moist with a thick layer of decomposing leaf litter, which is negatively associated with the availability of ants and termites.…”

“…This study revealed that forest is the preferred habitat of pangolin, with burrows mostly recorded in S. robusta followed by S. wallichii forests. This is in accord with other studies, which report burrows mostly in forested areas (Gurung, 1996;Acharya, 2001;Bhandari and Chalise, 2014;Katuwal et al, 2017Dhami et al, 2023). In forests, termites are very abundant (Ackerman et al, 2009), which could account for the high pangolin occurrence (Swart et al, 1999).…”

“…This study revealed that pangolin prefers red soil, which accords with the results of Dhami et al (2023) reported for Gorkha and Shrestha et al (2021) for Chitwan, Nepal. In contrast, various studies indicate that pangolin prefers brown soil (Suwal, 2011;Bhandari and Chalise, 2014;Suwal et al, 2020).…”

“…Based on the distribution of burrows pangolin distribution is not uniform. Similarly, Suwal (2011), Bhandari andChalise (2014), andDhami et al (2023) report non-uniform distribution of burrows on slopes of all aspects. So, all of the data support the idea that the distribution of pangolin burrows, in the absence of a consideration of the ecological parameters associated with their presence, is clumped.…”

Assessing illegal trade networks of two species of pangolins through a questionnaire survey in Nepal

“…Nepal has two of the eight extant species of pangolin found in the world: the Indian Pangolin Manis crassicaudata & Chinese Pangolin Manis pentadactyla (Suwal et al 2020;Dhami et al 2023). The Indian Pangolin is cryptic and has complex biology (Mohapatra et al 2021), i.e., a single one is born in the breeding season and is a diet specialist, which makes it vulnerable.…”