# A Collection of Best Practices for the Collection and Analysis of Bioacoustic Data
###### Abstract
More broadly, acoustic methods can be used to investigate topics related to population structure such as distribution and speciation across habitats or regions [12; 36; 37; 38; 39; 40], and population densities [41; 42; 43; 44]. A second major realm of recent interest in acoustics concerns the coordination of cooperative and competitive behavior, including feeding, aggression, and mating [1; 3; 15; 45]. In these contexts, acoustic data can be used to investigate cognition [46; 47], vocal learning [48; 49; 50; 51],  
Figure 1: Number of studies performed each year using passive acoustic data. Data were obtained by searching Google Scholar using “bioacoustics” + “category description” and then filtered per year. and the role of communication patterns and environmental pressures in shaping vocal signals and repertoires over evolutionary timescales [52; 53; 54; 55]. Yet, another major area of interest concerns acoustic interactions in the context of ecosystem biodiversity, which can be studied via passive acoustic monitoring [56; 57; 58; 59; 42]. Recently, inter-species variation in the structure of acoustic signals has been used to create biodiversity indices representing species richness [60; 61; 62; 20; 63], with one goal being to assess the impacts of environmental degradation on biodiversity [64]. As we develop the capacity to use acoustic data to monitor multiple species at once, sometimes combining passive and active acoustic methodologies, researchers have begun to use acoustic data to examine predator-prey interactions, both at broad and fine scales [65; 66; 67]. Our main aim in this paper is to bring together ideas and perspectives regarding the value and application of bioacoustic data and analysis for studies in population biology, ecology, and animal behavior. The authors represent a diverse group of bioacousticians in fields within the life and statistical sciences, and convened for a 2018 workshop on Bioacoustic Structure devised by [PERSON] and [PERSON], sponsored by the National Institute for Mathematical and Biological Synthesis (NIMBioS). Of the many topics addressed in our working group, a point that emerged was that the field of bioacoustics is sprawling, cutting across many areas and taxa, and that even though we all work in bioacoustics, there are sub-areas of which each of us was unaware or at least unfamiliar. Commonalities emerged, however, as we discussed challenges inherent to bioacoustic research, and considered best practices for addressing these challenges. This set forth to us the challenge of generating a single document to capture our excitement regarding the possibilities of bioacoustics, writ large. Towards this end, in this paper we will review a diverse set of case studies that we find particularly compelling, from six representative topics commonly addressed using bioacoustic data. Our overarching goal is to demonstrate the utility of, and suggest some best practices for, using bioacoustic approaches in studying topics broadly regarding the ecology, evolution, and behavior of vocalizing species. The first three topics address the use of passive acoustic data to describe and quantify vocal species diversity at scales ranging from subpopulation to ecosystem: species identification [58], population structure [68], and ecosystem biodiversity [69]. The next two topics relate to the evolution of signal structure, addressing ecological [70; 71] and cultural [52] factors affecting the evolution of acoustic signal structure. The final topic covers the use of acoustic data to examine broad-scale predator-prey interactions [72]. Within each topic, we identify best practices for collecting, analyzing, and interpreting acoustic data, and discuss methods to avoid common pitfalls that can hamper acoustic data interpretation.