Publication Date:
2022-05-25
Description:
Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 54 (2007): 1421-1444, doi:10.1016/j.dsr.2007.04.020.
Description:
Toothed whales produce short, ultrasonic clicks of high directionality and source level to probe their environment acoustically. This process, termed echolocation, is to a large part governed by the properties of the emitted clicks. Therefore derivation of click source parameters from free-ranging animals is of increasing importance to understand both how toothed whales use echolocation in the wild and how they may be monitored acoustically. This paper addresses how source parameters can be derived from free-ranging toothed whales in the wild using calibrated multi-hydrophone arrays and digital recorders. We outline the properties required of hydrophones, amplifiers and analog to digital converters, and discuss the problems of recording echolocation clicks on the axis of a directional sound beam. For accurate localization the hydrophone array apertures must be adapted and scaled to the behavior of, and the range to, the clicking animal, and precise information on hydrophone locations is critical. We provide examples of localization routines and outline sources of error that lead to uncertainties in localizing clicking animals in time and space. Furthermore we explore approaches to time series analysis of discrete versions of toothed whale clicks that are meaningful in a biosonar context.
Description:
This work was supported by a Steno Fellowship from the Danish National Science Foundation to PTM, a grant from the Carlsberg Foundation to MW with additional support to the authors from Reson, the Novo Nordisk Science Foundation, Aarhus University Research Fund, and the Oticon Foundation.
Keywords:
Toothed whale
;
Ultrasound
;
Recording
;
Click
;
Hydrophone
;
Array
;
Echolocation
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
