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Detecting rapid changes in mammal composition at large spatial scales requires efficient detection methods. Many studies estimate species composition with a single survey method without asking whether that particular method optimises detection for all occurring species and yields reliable community-level indices. We explore the implications of between-method differences in efficiency, consistency, and sampling effort for the basic characterisation of assemblages of medium to large mammals in a region with three contrasted Mediterranean landscapes. We assessed differences between camera traps, scent stations, scat surveys, and track surveys. Using track surveys, we detected all species present in the regional pool (13) and obtained the most accurate description of local species richness and composition with the lowest sampling effort (16 sampling units and 2 survey sessions at most). Had we chosen camera traps, scent stations, or scat surveys as the only survey method, we would have underestimated species richness (9, 11, and 12 species, respectively) and misrepresented species composition in varying degrees. Preliminary studies of method performance inform whether single or multiple survey methods are needed and eventually which single method might be most appropriate. Without such a formal assessment current practices may produce unreliable and incomplete species inventories, ultimately leading to incorrect conclusions about the impact of human activity on mammal communities.

Monitoring local occupancy and the regional distribution of wild mammals is essential to guide species management and set conservation priorities. However, variables such as weather, substrate hardness, or habitat characteristics may indirectly affect the performance of the methods employed for monitoring mammal occurrence. Little information exists about the influence of spatio-temporal factors on the performance of survey methods and its implications for mammal monitoring. Using data from a heterogeneous region in the Guadiamar River basin, SW Spain, which encompass forest, agricultural, and mosaic landscapes, we (1) explore whether four widely used detection methods, namely camera traps, scent stations, track surveys, and scat surveys, differ in efficiency; (2) test the hypothesis that spatio-temporal factors do not affect method efficiency; and (3) examine the effect of landscape on the replication effort needed to detect target species. After controlling for variation in mammal occurrence across space and over time, the interaction between spatio-temporal factors and detection methods was not significant. Likewise, we found a negligible influence of landscape type on the replication effort needed to detect species actually present. When compared to camera traps, scent stations, and scat surveys, track surveys were the most efficient and fastest methodology for surveying mammals in our study landscapes. Monitoring programs of mammal occurrence are often applied to broad and heterogeneous regions and/or during extended periods. Therefore, survey methods should describe not only spatio-temporal variation in mammal abundance or activity but also maintain high detection efficiency in a variety of environmental conditions. The detection efficiency of each survey method changed little regardless of considerable environmental variation, making more reliable the marked differences between methods in their ability to detect target species. We recommend accounting for the effect of spatio-temporal factors as potential sources of variation in order to test whether our results can be generalized and to increase the quality of large-scale monitoring of mammal occurrence.

Analyzing how similar social perception and ecological field data are might help identify potential biases in identifying and managing human-carnivore conflicts. We analyzed the degree of similarity between the perceived and field-measured relative abundance to unveil whether attitude towards carnivores of two groups of stakeholders, namely hunters and other local people, is underpinned or it is instead biased by alternative factors. Our results indicate that, in general, mesocarnivore perceived abundances were generally different to actual species abundance. We also found that the perceived abundance and attributed damage to small game species were related with respondents’ ability to identify the carnivore species. We underline the existence of bias and the need to increase people knowledge on species distribution and ecological characteristics before adopting decisions when managing human-carnivore conflicts, especially for stakeholders that are directly involved in.