Space-use patterns of Malay civets (Viverra tangalunga) persisting within a landscape fragmented by oil palm plantations

Context Agricultural land use is expanding and is a major driver of the biodiversity crisis. Land use planning initiatives seeking to optimize wildlife conservation are hindered by a lack of baseline data quantifying species’ tolerance to human-modified landscapes. Objectives We explored the influence of landscape characteristics on the fine-scale space-use patterns of a model generalist carnivore, the Malay civet (Viverra tangalunga), within degraded tropical forests and oil palm plantations. Methods We collected over 20,000 GPS locations from 21 male civets in Sabah, Malaysian Borneo to evaluate the species’ space-use patterns and habitat utilization processes. We used movement-based modeling to determine home ranges, and combined the results with high-resolution remotely sensed habitat characteristics. We developed resource utilization functions to determine individual and population-level functional responses to proximity to plantation edge, distance to water, terrain ruggedness, forest structure, and functional diversity. Results Civets foraged within oil palm plantations, yet all animals utilized forests. Home ranges scaled with proportion of plantation within both total and core ranges. Resource utilization functions reported individualism in the species’ responses to habitat characteristics. At the population-scale, civets consistently and more intensely used habitats closer to plantation edges and taller tree canopies. Conclusions Although plantations did not pose an inhospitable matrix, oil palm agriculture is a less suitable habitat than remnant forests for civets. Proximity measures and forest structure influenced the spatial behaviors of this adaptable generalist, highlighting the importance of protected areas. We recommend land-sparing and -sharing approaches to facilitate carnivore persistence across oil palm degraded landscapes.

Improving studies of resource selection by understanding resource use

SUMMARYUnderstanding the resource needs of animals is critical to their management and conservation. Resource utilization functions (RUFs) provide a framework to investigate animal-resource relationships by characterizing variation in the amount of resource use. In this context a ‘resource’ is any aspect of a species' fundamental niche that can be mapped throughout the area of investigation (such as study area or home range). Extensive global positioning system (GPS) data from 17 cougars (Puma concolor) demonstrate the utility and potential challenges of estimating RUFs within the home range for far-ranging species. Ninety-nine per cent utilization distributions (UDs) estimated using bivariate plug in, univariate least-squares cross-validation and reference bandwidth selection methods were compared. Distance to water, per cent clear-cut and regenerating forest, and slope were used to estimate cougar RUFs. UDs derived from GPS data were more refined, and plug-in UDs were least similar to UDs derived from other bandwidths. RUFs were resilient to variation in the smoothing parameter, with all methods yielding coefficients that largely reflected observations of foraging ecology and behaviour. Cougars were individualistic, but use was generally positively associated with the presence of regenerating forest and inversely associated with steep slopes. Advances in technology allow for greater accuracy and resolution of the UD, but software improvements and spatially explicit information on animal behaviour are needed to better understand resource use.