Comparative efficacy of sign surveys, spotlighting and audio playbacks in a landscape-scale carnivore survey

Abstract

Many carnivores are difficult and labour-intensive to detect, often leading to prohibitivelyhigh effort and cost in large-scale surveys.However,such studies provide information that isimportant for effective management and conservation. Here, we evaluate the suitability ofthree survey methods for landscape-scale multi-species monitoring. We compare signsurveys, spotlighting, and audio playbacks in terms of detection efficiency, precision, effort,and cost. Sign surveys out-performed the other methods in all comparison criteria, althoughsupplementary methods were needed for some species and sites. We found that usingestablished analysis techniques, robust landscape-scale abundance estimates wouldrequire unrealistically high effort and cost. Occupancy estimation required considerablylower sample sizes and was therefore more economical. We conclude that sign-basedoccupancy estimates constitute a versatile and efficient option for future large-scale,multi-species carnivore surveys.