Dear MARMAM-readers,

 

We are pleased to inform you that our paper ‘Separating underwater ambient noise from flow noise recorded on stereo acoustic tags attached to marine mammals’,  by A.M. von Benda-Beckmann, P. J. Wensveen, F. I.P. Samara, S. P. Beerens, P. J. O. Miller, is now available online at the Journal of Experimental Biology, 219, 2271-2275, 2016.

 

http://jeb.biologists.org/content/early/2016/05/25/jeb.133116

 

Abstract:

Sound recording acoustic tags attached to marine animals are commonly used in behavioural studies. Measuring ambient noise is of interest to understand responses of marine mammals to anthropogenic underwater sound, or to assess their communication space. Noise of water flowing around the tag reflects the speed of the animal, but hinders ambient noise measurement. Here we describe a correlation-based method for stereo acoustic tags to separate the relative contributions of flow and ambient noise. The uncorrelated part of the noise measured in DTAG recordings related well to animal swim speed of a humpback whale (Megaptera novaeangliae), thus providing a robust measure of flow noise over a wide frequency bandwidth. By removing measurements affected by flow noise, consistent ambient noise estimates were made for two killer whales (Orcinus orca) with DTAGs attached simultaneously. The method is applicable to any multi-channel acoustic tag, enabling application to a wide range of marine species.

 

For any inquiries or requests please contact me at: sander.vonbenda@tno.nl.

 

Kind regards,

 

Sander von Benda-Beckmann

 

Netherlands Organisation for Applied Scientific Research (TNO)

Acoustics & Sonar Department

Oude Waalsdorperweg 63

2597 AK The Hague

The Netherlands