The ability of animals to move across complex landscapes is critical for maintaining viable populations in the landscape. For an apex predator like the tiger (Panthera tigris), which is territorial and requiring large home range, habitat connectivity through biological corridors is vital. In Bhutan, the landscape conservation approach for tiger was initiated since 1999 when biological corridors were first established. Yet, the status of connectivity is not widely known. This study assessed the structural connectivity of biological corridor number 8 (BC8) for the tiger movements between national parks considering the ecological and anthropogenic variables influencing tiger and its prey.
Camera trap datasets were used to assess the single-season occupancy of three principal prey species of tiger, sambar (Rusa unicolor), barking deer (Muntiacus muntjak), and wild boar (Sus scrofa), and to determine the habitat use probability of tiger. A questionnaire survey was administered to assess the current trends of human-tiger conflict, and people’s perception towards conservation.
Barking deer had the highest occupancy estimate (ψ ± SE) 0.52 ± 0.09, followed by sambar (ψ ± SE) 0.49 ± 0.03 and wild boar (ψ ± SE) 0.45 ± 0.07. The influence of ecological and anthropogenic variables like elevation, aspect, slope, distance to river, and distance to settlement varied among the three prey species. Predicted occupancy map showed probable niche partitioning between species, thereby enabling better distribution of principal prey and thus the connectivity. Tiger habitat use probability was influenced positively by elevation and negatively by aspect and slope. Livestock predation was the prevailing human-tiger conflict in the area with tiger accounting 76.49% of the total kill in the past two years. Nomads were more vulnerable than agro-pastoralists, and livestock predation was higher during the winter. Over 80% of the respondents were not aware of biological corridors and over 30% perceived negative attitude towards tiger conservation and corridor management.
The structural connectivity maintained by ecological variables and prey species would enable tiger movements across the BC8, but human-tiger conflict needs to be mitigated, and people should be educated for conservation. Management of the BC8 by developing the management plan remains the most pressing need.