title: Long-term underwater sound measurements in the shipping noise indicator bands 63Hz and 125Hz from the port of Falmouth Bay, UK.
abstract: Chronic low-frequency anthropogenic sound, such as shipping noise, may be negatively affecting marine life. The EU's Marine Strategy Framework Directive (MSFD) includes a specific indicator focused on this noise. This indicator is the yearly average sound level in third-octave bands with centre frequencies at 63Hz and 125Hz. These levels are described for Falmouth Bay, UK, an active port at the entrance to the English Channel. Underwater sound was recorded for 30min h(-1) over the period June 2012 to November 2013 for a total of 435days. Mean third-octave levels were louder in the 125-Hz band (annual mean level of 96.0dB re 1μPa) than in the 63-Hz band (92.6dB re 1 μPa). These levels and variations are assessed as a function of seasons, shipping activity and wave height, providing comparison points for future monitoring activities, including the MSFD and emerging international regulation.
authors.affiliation: College of Engineering, Mathematics and Physical Sciences, University of Exeter, Penryn Campus, TR10 9FE, UK. Electronic address: J.K.Garrett@exeter.ac.uk.
authors.forename: J K
authors.initials: JK
authors.lastname: Garrett
authors.affiliation: Department of Physics, University of Bath, Claverton Down, BA2 7AY, UK. Electronic address: P.Blondel@bath.ac.uk.
authors.forename: Ph
authors.initials: P
authors.lastname: Blondel
authors.affiliation: Centre for Ecology and Conservation, University of Exeter, Penryn Campus, TR10 9FE, UK; Environment and Sustainability Institute, University of Exeter, Penryn Campus, TR10 9FE, UK. Electronic address: B.J.Godley@exeter.ac.uk.
authors.forename: B J
authors.initials: BJ
authors.lastname: Godley
authors.affiliation: Centre for Ecology and Conservation, University of Exeter, Penryn Campus, TR10 9FE, UK. Electronic address: S.K.Pikesley@exeter.ac.uk.
authors.forename: S K
authors.initials: SK
authors.lastname: Pikesley
authors.affiliation: Environment and Sustainability Institute, University of Exeter, Penryn Campus, TR10 9FE, UK. Electronic address: M.J.Witt@exeter.ac.uk.
authors.forename: M J
authors.initials: MJ
authors.lastname: Witt
authors.affiliation: College of Engineering, Mathematics and Physical Sciences, University of Exeter, Penryn Campus, TR10 9FE, UK. Electronic address: L.Johanning@exeter.ac.uk.
authors.forename: L
authors.initials: L
authors.lastname: Johanning
mesh_terms: D000162:Acoustics; D061006:Bays; D004784:Environmental Monitoring / Q000379:methods; D009622:Noise; D012621:Seasons; D012767:Ships / Q000706:statistics & numerical data; D013016:Sound; D013018:Sound Spectrography; D006113:United Kingdom
keywords: Disturbance; MSFD; Marine; Shipping noise; Third-octave levels; Underwater sound