We emphasize that there is no “best” bat detector. Each of the three basic types of detector systems available today
– heterodyne, frequency division, and time expansion – has different capabilities and limitations. We review these
capabilities and limitations within the context of the goals of different research and/or monitoring projects, the bat
fauna being investigated, and our own experience. We summarize the practical and technical features of different
detector systems in relation to 1) sensitivity, 2) ability to record and process ultrasound, and 3) ability to describe
the parameters necessary for the identification of bats to species. We also categorize a range of possible applications
of detector types to field research with regard to scale and resolution in space and time. On the basis of the relationship
between research questions and the resulting research design, we discuss the