Challenges and opportunities for bioacoustics in the study of rare species in remote environments

Abstract

For many habitat specialists, data deficiencies are directly attributable to the rugged terrain they inhabit. Based on a recent survey effort for one such species, the threatened Yosemite toad (Anaxyrus canorus), we describe the prospects for acoustic monitoring of rare and declining species in remote areas. Passive acoustic monitoring can be a valuable way of increasing the scale at which vocally active populations are surveyed and the level of detail obtained, particularly in cases where direct observation of the species is impeded by cryptic behavior and inaccessible habitat. Challenges include limitations to hardware, teams' physical and mental constraints, and survey design. Teams must have substantial expertise about the species of interest, bioacoustics, and the terrain to be surveyed, and effective communication at all stages is essential. Particularly for globally endangered taxa like anurans, bioacoustics may be a powerful way to reduce widespread data deficiencies.