Measurement and characterization of a soundscape of captive southern white rhinoceros (Ceratotherium simum simum) at a wildlife park conservation center.

摘要

Many animals, including the myopic rhinoceros, depend on hearing and smell for navigation and to interpret their environment. For them, the "soundscape" and "scentscape" are equivalent to our landscape. Noise damages humans physiologically, including reproductively, and likely damages other mammals. Rhinos vocalize sonically and infrasonically but audiograms are unavailable. Infrasonic noise tends to be chronic in urban areas, which frequently surround city zoos. Rhinos' biological and social management have been studied but little attention, if any, has been paid to their soundscapes. This project develops a standard by which such soundscapes may be measured, documented, and compared, so that once a wide range of rhino facilities have been similarly investigated, correlations could be sought between their sound metrics and the health and well-being of their animals.;The interests of geographers overlap many disciplines, but the questions raised by, and the approaches of geographers frequently differ from those addressed by the original specialists, so a broader understanding of the soundscape and ways to record it may well add value to acoustic studies while simultaneously deepening geographic knowledge. This research asks: How can a soundscape of captive southern white rhinoceros (Ceratotherium simum simum) be comprehensively measured and characterized? What does doing so inform about their environment of captivity? How can this method be employed to understand the contrasts of the soundscapes of captivity and natural habitats? To begin to answer these questions, the following goals are addressed: 1. To develop a series of procedures to comprehensively record, measure, analyze, and characterize a broadband white rhino soundscape; 2. To note their vocalizations, and to roughly estimate the bandwidth used by these particular animals; 3. By demonstrating that techniques and language not normally used in the discipline of Geography could broaden its scope and expand the tools available to those investigating their environment, to invite geographers and others from non-acoustic backgrounds to become aware of the soundscape and to pose new questions; 4. To demonstrate how the processing and analysis of the data collected at FRWC can be formulated to characterize the soundscape that their rhinos experience.;This study is undertaken at the white rhinoceros enclosure of Fossil Rim Wildlife Center (FRWC), one of nine U.S. facilities to breed this species in recent years. Fossil Rim's white rhino soundscape was recorded continuously throughout a week of normal park activities by five acoustic, infrasonic and seismic acquisition systems to sense frequencies from 0.1 Hz to 22,020 kHz, and the resultant broadband sound metrics were measured. It is not within the scope of this project to publish all the possible results, but a sample is provided to illustrate the use and effectiveness of the system. Friday 18th October, 2014 was subjectively analyzed via a sound event log before recordings were processed using Raven Interactive Sound Analysis Software, and by SongMeter SM2+ Data Logs. Data from three infrasonic channels were averaged and preliminarily processed in Matlab, as were the three geophone seismic channels. For perspective, Friday was compared to a preliminary sonic analysis of Monday 21st October. It was ascertained that the FRWC white rhinoceros enclosure retains many characteristics of a natural environment, despite being exposed to some form of anthrophonic noise much of the time. Once a wide variety of rhino enclosure soundscapes have been measured, if relationships are discovered between certain acoustic parameters and the health and well-being of their animals, the soundscapes of other captive species could be similarly examined and acoustic environments could be modified to better suit the species concerned.