Wildlife Roadkill in Chitwan, Nepal: Identifying Affected Species, Potential Drivers and Hotspots

Roadkill poses a significant threat to species conservation. However, there is scarce information on roadkill of wild animals. Therefore, to address these research gaps, this study aimed to assess roadkill status of vertebrates, including their conservation status and possible drivers such as seasons, structure of road and habitat types, using direct observation methods over four seasons (autumn, winter, summer and spring) in 2024-2025 on two national highways: part of East-West Highway (H01) and Madan Ashrit Highway (H05). The status of road-killed vertebrates was evaluated by using relative frequency and encounter rate. The seasonal difference among the reported road-killed vertebrates were visualized using venn diagram. The generalized linear model was used to show the relationship between total number of roadkill cases of vertebrates with different variables such as seasons, habitat types and condition of road. Similarly, this study also mapped the roadkill hotspots based on data using the Inverse Weighted Distance (IDW) algorithms. A total of 618 cases involving 36 species of wild vertebrates were reported on two highways, comparatively higher in H01. Among the reported species, 36.1% were mammals following 27.78% Aves, 25% reptiles and 11.1% amphibians. This study also recorded two globally Near Threatened (NT), four nationally Vulnerable (VU), and two nationally Near Threatened (NT) roadkill vertebrates. Roadkill risk is closely associated with habitat types. The road sections that cross between forests, forest edges, and residential areas comparatively have higher roadkill cases than croplands. River crossings are critical risk zones for wildlife vehicle encounters. Major roadkill hotspots on both national highways were identified, and recommendations were made for implementing speed limits and constructing underpasses and overpasses during road renovations.