EN
The use of acoustic detectors to investigate differential use of habitat by bats has become increasingly common. However, in many of these studies, authors failed to clearly articulate assumptions a priori. For example, spatial and temporal scales were rarely defined. True replication is rarely reported, suggesting that authors assume that these systems are both spatially and temporally static. In this study, we attempted to clearly identify underlying assumptions of this technique, thereby limiting level of inference to a clearly defined and repeatable degree. We followed strict assumptions beforehand and were able to classify bat calls into guilds based on acoustic data. Lack of experience in acoustic identification by technicians did not affect the outcome, as guilds were based on bat call sequences following strict rules of classification. Individuals in guilds were not randomly distributed across sample locations. However, distribution of guild members did not suggest differential use of habitat, as within habitat variation was often greater than that observed among types of habitat. Explicitly stating assumptions before surveys were conducted ‘protected’ us from making incorrect inferences. We suggest that care be taken when attempting to infer differential use of habitat by bats using acoustic techniques.