200 kHz Commercial Sonar Systems Generate Lower Frequency Side Lobes Audible to Some Marine Mammals

Journal Article

Title: 200 kHz Commercial Sonar Systems Generate Lower Frequency Side Lobes Audible to Some Marine Mammals
Publication Date:
April 15, 2014
Journal: Plos One
Volume: 9
Issue: 4
Pages: 1-6
Publisher: Plos One
Stressor:

Document Access

Website: External Link
Attachment: Access File
(317 KB)

Citation

Deng, Z.; Southall, B.; Carlson, T.; Xu, J.; Martinez, J.; Weiland, M.; Ingraham, J. (2014). 200 kHz Commercial Sonar Systems Generate Lower Frequency Side Lobes Audible to Some Marine Mammals. Plos One, 9(4), 1-6.
Abstract: 

The spectral properties of pulses transmitted by three commercially available 200 kHz echo sounders were measured to assess the possibility that marine mammals might hear sound energy below the center (carrier) frequency that may be generated by transmitting short rectangular pulses. All three sounders were found to generate sound at frequencies below the center frequency and within the hearing range of some marine mammals, e.g. killer whales, false killer whales, beluga whales, Atlantic bottlenose dolphins, harbor porpoises, and others. The frequencies of these sub-harmonic sounds ranged from 90 to 130 kHz. These sounds were likely detectable by the animals over distances up to several hundred meters but were well below potentially harmful levels. The sounds generated by the sounders could potentially affect the behavior of marine mammals within fairly close proximity to the sources and therefore the exclusion of echo sounders from environmental impact analysis based solely on the center frequency output in relation to the range of marine mammal hearing should be reconsidered.

Find Tethys on InstagramFind Tethys on FacebookFind Tethys on Twitter
 
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.