A systematic review of passive acoustic monitoring for anuran conservation

Passive Acoustic Monitoring (PAM) has emerged as a valuable tool for conservation thanks to its capacity to collect data at large spatial and temporal scales. However, analysing vast amount of data can be challenging, and PAM performances compared to traditional methods are largely untested. Here, we review recent research using PAM on anurans (72 peer-reviewed studies). The number of annual publications has risen from two in 2013 to 12 in 2023 with studies in 17 countries across five continents. Analysis showed that Europe and North America were sampled more than expected based on their species richness. In contrast, Africa and Asia were under sampled. At the habitat level, there were differences in forest systems, with temperate forests sampled more than expected. We reviewed study design and analysis techniques to guide researchers in selecting methods depending on study purpose and target species characteristics. Technological developments can assist data analysis and increase application in developing countries. Global funding and international academic cooperation can also enhance research output in neglected regions. Standardisation in study design, data storage and sharing, increased research on threatened and invasive species, and development of real-time monitoring should be areas of research to enhance the scope of PAM.