Dear Colleagues, Those of you interested in the effects of underwater noise pollution on marine mammals may be interested in our recent Open Access publication in Scientific Reports: Underwater noise levels in UK waters (2016) Nathan D. Merchant, Kate L. Brookes, Rebecca C. Faulkner, Anthony W. J. Bicknell, Brendan J. Godley & Matthew J. Witt Scientific Reports 6, Article number: 36942 http://www.nature.com/articles/srep36942 Abstract: Underwater noise from human activities appears to be rising, with ramifications for acoustically sensitive marine organisms and the functioning of marine ecosystems. Policymakers are beginning to address the risk of ecological impact, but are constrained by a lack of data on current and historic noise levels. Here, we present the first nationally coordinated effort to quantify underwater noise levels, in support of UK policy objectives under the EU Marine Strategy Framework Directive (MSFD). Field measurements were made during 2013–2014 at twelve sites around the UK. Median noise levels ranged from 81.5–95.5 dB re 1 μPa for one-third octave bands from 63–500 Hz. Noise exposure varied considerably, with little anthropogenic influence at the Celtic Sea site, to several North Sea sites with persistent vessel noise. Comparison of acoustic metrics found that the RMS level (conventionally used to represent the mean) was highly skewed by outliers, exceeding the 97th percentile at some frequencies. We conclude that environmental indicators of anthropogenic noise should instead use percentiles, to ensure statistical robustness. Power analysis indicated that at least three decades of continuous monitoring would be required to detect trends of similar magnitude to historic rises in noise levels observed in the Northeast Pacific. Kind regards, Nathan Dr Nathan Merchant Principal Scientist, Noise & Bioacoustics Team Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK Tel: +44(0) 1502 527780 | Mob: +44 (0) 7789 651086 Email: nathan.merchant@cefas.co.uk<mailto:nathan.merchant@cefas.co.uk> [cid:image001.jpg@01D2402A.CD1ADEA0] https://scholar.google.co.uk/citations?user=XPctSoUAAAAJ&hl=en https://www.cefas.co.uk/services/research-advice-and-consultancy/underwater-... https://www.cefas.co.uk/media/52916/noise-bioacoustics.pdf Follow us on: [cid:image001.gif@01D09A11.D21ECDA0]<https://twitter.com/CefasGovUK>[cid:image002.gif@01D09A11.D21ECDA0]<http://www.linkedin.com/company/cefas> This email and any attachments are intended for the named recipient only. Its unauthorised use, distribution, disclosure, storage or copying is not permitted. If you have received it in error, please destroy all copies and notify the sender. In messages of a non-business nature, the views and opinions expressed are the author's own and do not necessarily reflect those of Cefas. Communications on Cefas’ computer systems may be monitored and/or recorded to secure the effective operation of the system and for other lawful purposes.
