Terrestrial Sound Monitoring Systems, A Methodology For Quantitative Calibration

We present a series of practical techniques designed to standardize, quantify and allow comparison of population information obtained from periodic automated terrestrial recordings of acoustic animals. From the experience obtained mainly from anuran monitoring systems, we discuss issues such as establishing comparable recording levels, calibrating the detection space for each station, establishing correlations with population densities and comparison with other acoustical surveys. We emphasize the need to obtain species-specific data on source levels (sound pressure levels).