Beaked whale density estimation from single hydrophones by means of propagation modeling.

Abstract

Passive acoustic sonar systems offer many advantages to the study of marine mammals. For density estimation studies, it is important to evaluate the probability of detecting an animal as a function of its distance from the receiving sensor. In this work, acoustic propagation modeling is used to estimate the transmission loss as a function of depth and range between a source whale and a single‐hydrophone receiver. The computed transmission loss is compared to ambient noise levels and source level distributions to estimate the detection probability as a function of range. Results will be compared to beaked whale data recorded on bottom‐mounted sensors in the Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas, where the location of clicks is relative to one hydrophone. Source level and beam pattern extracted from digital acoustic tags (DTags) applied to a sample of animals at the same location will also be used in the detection model, and beaked whale spatial density will be estimated. The d...