A comparative analysis of rocket noise recordings from wildlife acoustic monitoring devices

Abstract

Remote acoustic recorders are used in wildlife passive acoustical monitoring (PAM) and species identification. Such devices are designed to be relatively low-cost, user-friendly, weather-robust, and operate for extended periods with low maintenance. Usually, the precision of these devices is limited because most applications do not require high-fidelity measurements for typical wildlife PAM applications. However, the relatively low cost and flexibility of deployment beg the question if they can accurately record other noise sources, such as rocket launches. Such a situation calls for an evaluation of accuracy and a complete understanding of their capabilities and limitations. As such documentation is limited, this study seeks to characterize the acoustic performance of two commercially available wildlife acoustic monitoring devices: the Wildlife Acoustics SM-4 and the Cornell Ornithology Laboratory SwiftOne. We present acoustical results from a laboratory experiment and a field measurement of an orbital rocket launch. Comparisons to industry standard devices are made in the time and frequency domains and show the spectral characteristics of these devices. Recommendations are made regarding the use of these devices based on their performance.