Measuring hearing sensitivity of wild Dugongs in Moreton Bay, Australia (PDF)

Lucke, K., J.M. Lanyon, and D.R. Ketten

The Effects of Noise on Aquatic Life (2024)

DOI: 10.1007/978-3-031-10417-6_94-1

A pilot study to measure hearing capabilities in wild dugongs (Dugong dugon) was conducted in Moreton Bay, Australia. To successfully obtain hearing measurements, an approach for measuring auditory responses in wild dugongs using neurophysiological measures was developed. Preparatory to the measurements, basic head anatomy of dugongs was investigated to optimize placements of the acoustic transmitting and receiving neuronal sensors. Three dugongs were selected as suitable candidates for the auditory measurements based on the results of a preliminary health assessment. Following the absence of observable responses by the first animal, click and sinusoidally amplitude modulated signals were used as acoustic stimuli for the second and third animals, eventually resulting in reproduceable and scalable neuronal responses. The recorded neuronal signals represent a proof of concept for the first auditory measurement in wild dugongs. Valuable insights were gathered during the pilot study allowing optimization of the procedure for a planned follow-up study which will test a larger number of wild dugongs.