Combining high-resolution remote sensing and animal tracking data to yield new insights into animal landscape use in a changing world

Background/Question/Methods

The conservation of animal species in their natural habitat is becoming increasingly difficult. Anthropogenic pressures continue to squeeze available habitat and force animals into small, often fenced, protected areas and/or degraded and disturbed landscapes. Ensuring the long-term survival of many animal species requires a well-developed understanding of how animals use these increasingly constrained and novel landscapes, and how their behavior and distributions are affected by land use and climatic changes. To better inform conservation strategies in such areas, large-scale, accurate measurements of both habitat and animal use of such habitat are required, which are difficult to obtain from on-the-ground measurements. Recent advances in Light Detection and Ranging (LiDAR) have enabled high-resolution measurements of animal habitat, and, when combined with animal distributional, abundance or behavioral data, can be a powerful tool for understanding how animals use managed or disturbed landscapes, and how conservation strategies should adapt to these new environments. Here, we demonstrate the applicability of combining animal movement data with LiDAR remote sensing for animal conservation using two contrasting examples: the coexistence of African wild dogs (Lycaon pictus) and lions (Panthera leo) in South African savanna, and Bornean orangutan (Pongo pygmaeus) use of degraded rainforest in Malaysian Borneo.

Results/Conclusions

By combining temporally overlapping telemetry data from dominant lions and subordinate African wild dogs with high-resolution LiDAR data in an integrated step selection analysis, we show how fine-scaled landscape heterogeneity can facilitate carnivore coexistence. The primary wild dog lion-avoidance strategy in our study site was to select landscape features that aid in lion avoidance, instead of previously documented spatial avoidance of lions. These findings suggest that spatial landscape heterogeneity could represent an alternative mechanism for carnivore coexistence, especially as ever-shrinking carnivore ranges force inferior competitors into increased contact with dominant species. To gain insights into how orangutans use human-modified forests, we combined visual observations of orangutan movements with LiDAR data on forest canopy attributes. Structural attributes of the upper forest canopy were the dominant determinant of orangutan movement among all age and sex classes, with orangutans more likely to move in directions of increased canopy closure, tall trees, and uniform height. These results suggest that although orangutans make use of disturbed forest, they select certain canopy attributes within these forests, indicating that not all disturbed forest is of equal value for the long-term sustainability of orangutan populations.