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Atzeni, L., Cushman, S. A., Bai, D., Wang, J., Chen, P., Shi,
K., Riordan, P. (2020). Meta-replication, sampling bias, and multi-scale model selection:
A case study on snow leopard (Panthera uncia) in western China. Ecology and Evolution, , 1–27.
Abstract: Replicated multiple scale species distribution models (SDMs)
have become increasingly important to identify the correct variables
determining species distribution and their influences on ecological
responses. This study explores multi-scale habitat relationships of the
snow leopard (Panthera uncia) in two study areas on the Qinghai–Tibetan
Plateau of western China. Our primary objectives were to evaluate the
degree to which snow leopard habitat relationships, expressed by
predictors, scales of response, and magnitude of effects, were
consistent across study areas or locally landcape-specific. We coupled
univariate scale optimization and the maximum entropy algorithm to
produce multivariate SDMs, inferring the relative suitability for the
species by ensembling top performing models. We optimized the SDMs based
on average omission rate across the top models and ensembles’ overlap
with a simulated reference model. Comparison of SDMs in the two study
areas highlighted landscape-specific responses to limiting factors.
These were dependent on the effects of the hydrological network,
anthropogenic features, topographic complexity, and the heterogeneity of
the landcover patch mosaic. Overall, even accounting for specific local
differences, we found general landscape attributes associated with snow
leopard ecological requirements, consisting of a positive association
with uplands and ridges, aggregated low-contrast landscapes, and large
extents of grassy and herbaceous vegetation. As a means to evaluate the
performance of two bias correction methods, we explored their effects on
three datasets showing a range of bias intensities. The performance of
corrections depends on the bias intensity; however, density kernels
offered a reliable correction strategy under all circumstances. This
study reveals the multi-scale response of snow leopards to environmental
attributes and confirms the role of meta-replicated study designs for
the identification of spatially varying limiting factors. Furthermore,
this study makes important contributions to the ongoing discussion about
the best approaches for sampling bias correction.
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Filla, M., Lama, R. P., Filla, T., Heurich, M., Balkenhol, N., Waltert, M., Khorozyan, I. (2022). Patterns of livestock depredation by snow leopards and effects of intervention strategies: lessons from the Nepalese Himalaya. Wildlife Research, .
Abstract: Context: Large carnivores are increasingly threatened by anthropogenic activities, and their protection is among the main goals of biodiversity conservation. The snow leopard (Panthera uncia) inhabits high-mountain landscapes where livestock depredation drives it into conflicts with local people and poses an obstacle for its conservation.
Aims: The aim of this study was to identify the livestock groups most vulnerable to depredation, target them in implementation of practical interventions, and assess the effectiveness of intervention strategies for conflict mitigation. We present a novel attempt to evaluate intervention strategies for particularly vulnerable species, age groups, time, and seasons.
Methods: In 2020, we conducted questionnaire surveys in two regions of the Annapurna Conservation Area, Nepal (Manang, n = 146 respondents and Upper Mustang, n = 183). We applied sample comparison testing, Jacobs’ selectivity index, and generalised linear models (GLMs) to assess rates and spatio-temporal heterogeneity of depredation, reveal vulnerable livestock groups, analyse potential effects of applied intervention strategies, and identify husbandry factors relevant to depredation.
Key results: Snow leopard predation was a major cause of livestock mortality in both regions (25.4–39.8%), resulting in an estimated annual loss of 3.2–3.6% of all livestock. The main intervention strategies (e.g. corrals during night-time and herding during daytime) were applied inconsistently and not associated with decreases in reported livestock losses. In contrast, we found some evidence that dogs, deterrents (light, music playing, flapping tape, and dung burning), and the use of multiple interventions were associated with a reduction in reported night-time depredation of yaks.
Conclusions and implications: We suggest conducting controlled randomised experiments for quantitative assessment of the effectiveness of dogs, deterrents, and the use of multiple interventions, and widely applying the most effective ones in local communities. This would benefit the long-term co-existence of snow leopards and humans in the Annapurna region and beyond.
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