Using local ecological knowledge to improve large terrestrial mammal surveys, build local capacity and increase conservation opportunities

Field information is essential for developing conservation actions, but standard methods for surveying wildlife are often inefficient in large, remote areas. Without efficient methods, surveying is difficult or even impossible. Consequently, some of the most threatened species and regions remain un- or under-surveyed, e.g. South American Chaco. Survey methods based on local ecological knowledge (LEK-methods) could be useful for surveying these areas and species. However, LEK-methods may be inaccurate and are rarely evaluated or compared to standard-methods. This is the first large-scale study evaluating the performance of two LEK-methods, and comparing it with the performance of standard-methods, for detecting three species of large terrestrial mammals. We used a locally-based survey (LBS) and interviews as LEK-methods, and transect and camera trapping as standard survey methods. We estimated the probability of detecting each species with each method, of having false-presences and their cost. We also quantitatively analysed the ability of LBS to build local capacity, focusing on conservation, research and working skills. We found that compared to standard-methods, LEK-methods increase detection probabilities of three species while providing accurate information. LBSs are more expensive than interviews but improve local capacities, raising the chances of successful implementation of community-based conservation programmes. Interviews are optimal for rapid assessments and can be useful for wildlife monitoring. Before using LEK-methods, we recommend pilot studies to determine estimators´ variability. Overall, this study shows that LEK-based methods can be efficient and accurate for detecting large mammals in remote areas. Furthermore, LEK-methods can help develop legitimate conservation initiatives. The probability of detecting a species depends on the species characteristics and on the methods used in the survey. For three species with different biological and ecological characteristics -white-lipped, collared or chacoan peccaries (Tayassu pecari, Pecari tajacu and Parachoerus wagneri)-, locally-based surveys provided the highest detection probabilities. The probability of detecting these species with the locally-based survey and interviews to hunters are higher than with standard-methods. The season (rainy/dry) was differentiated when estimating white-lipped peccary's detection probabilities because this factor had a significant effect on estimations. [Disp