Evaluating wildlife activity and corridor functionality: a study of underpasses in and around Rajaji National Park, India

Habitat fragmentation threatens biodiversity, making wildlife corridors vital for maintaining ecological connectivity. This study evaluated the functionality of three corridors—Chilla-Motichur, Teenpani, and Laltappar—in and around Rajaji National Park, Uttarakhand, India. We deployed camera traps at these corridors and surrounding forest areas for 8,198 trap nights to monitor the wildlife use of the corridors. We recorded 17 species of wild animals in the connected forested area and nine within the corridors. The Wild Pig Sus scrofa and Sambar Rusa unicolor were the most frequently captured species, with the highest Relative Abundance Index (RAI) in the Teenpani corridor. Activity patterns of wild species showed changes in the corridor compared to forest areas. Chital Axis axis exhibited continuous activity in corridors but an early-morning peak in forests (Δ = 0.68). Asiatic Elephant Elephas maximus shifted from daytime activity in forests to nocturnal peaks in corridors, likely avoiding human presence (Δ = 0.48). Sambar avoided daytime activity in the corridor compared to activity in the forest (Δ = 0.55), while Wild Pig maintained nocturnal peaks across both habitats (Δ = 0.71). Human activity, primarily diurnal, overlapped with Chital (Δ = 0.61) and increased potential encounters with Elephants and Leopards during evening hours (Δ = 0.25 and 0.39, respectively). Mitigation measures, such as habitat restoration and managing anthropogenic activities, are crucial for strengthening corridor functionality. The recent reintroduction of tigers in western Rajaji underscores the importance of these corridors for species connectivity and genetic exchange. This study provides valuable insights into managing wildlife corridors in human-dominated landscapes, highlighting their role in biodiversity conservation.