Effects of human footprint on movement of large carnivores
As human activities increase, the collateral loss of habitat and biodiversity is accompanied by a change in movement of animals through fragmented landscapes (Tucker et al., 2018). Landscape structure affects movement parameters because different cover types in the landscape offer different levels of risk and benefit. It is important to study the movement of animals through these landscapes. Land use types across home ranges of large carnivore species were not significantly different with the single exception of wolves which live primarily in grasslands and human altered landscapes (Fig 3). Historically, wolves adapted to live in human dominated landscapes as they evolved near humans (Anderson, 2018). However, our results indicate that the wolves move faster in human dominated landscapes to negotiate human pressures within large home ranges.
Comparison of land use types within tiger home ranges suggested that proportion of forest cover was not significantly different whereas agriculture outside and inside PAs was significantly different (P forest=0.06;P agriculture=0.03 respectively). It is worth discussing that home ranges of tigers outside PAs were primarily forest areas (72.72%).
However, forest outside PAs is fragmented with high human density and road network which may explain why tigers outside PAs have larger home ranges. To negotiate this landscape, tigers outside PAs also move at higher speeds than inside PAs. We examined the proportion of human population density inside home ranges of the 4 large carnivores in our study areas. As expected, home range of wolves consisted of relatively high human density followed by leopard and tigers outside PAs. In our study area, the leopard is pushed to the fringe areas of the PA due to high density of larger predator, the tiger. Tigers inside PAs (0.29 human/100 km2) and dholes (0.51 human/100 km2) showed the least proportion of human pressure in their home ranges signifying they occur in prime forested areas (Fig 4). Dholes in our study area show higher human population pressure than tigers in their home range as a strategy to avoid large predators. In order to avoid competition, dholes established intensive use areas near PA fringes (Ghaskadbi, P. 2017unpublished data).
Across our study sites, the home range of wolves had the maximum density of roads (56.6) followed by tigers outside PAs (25.7). The home range of dholes showed the least density of roads (5.5) (Fig 5). All carnivores had primary roads passing through their home ranges, but the disturbance caused by them need not be the same. This is because the roads inside PAs in our study site was a non-functioning highway with only tourist activity in limited time windows.