Data from: Responses of bottlenose dolphins and harbor porpoises to impact and vibration piling noise during harbor construction

The development of risk assessments for the exposure of protected populations to noise from coastal construction is constrained by uncertainty over the nature and extent of marine mammal responses to man-made noise. Stakeholder concern often focuses on the potential for local displacement caused by impact piling, where piles are hammered into the seabed. To mitigate this threat, use of vibration piling, where piles are shaken into place with a vibratory hammer, is often encouraged due to presumed impact reduction. However, data on comparative responses of cetaceans to these different noise sources are lacking. We studied the responses of bottlenose dolphins and harbor porpoises to both impact and vibration pile driving noise during harbor construction works in northeast Scotland, using passive acoustic monitoring devices to record cetacean activity and noise recorders to measure and predict received noise levels. Local abundance and patterns of occurrence of bottlenose dolphins were also compared with a five-year baseline. The median peak-to-peak source level estimated for impact piling was 240 dB re 1 μPa (single-pulse sound exposure level [SEL] 198 dB re 1 μPa2 s), and the r.m.s. source level for vibration piling was 192 dB re 1 μPa. Predicted received broadband SEL values 812 m from the piling site were markedly lower due to high propagation loss: 133.4 dB re 1 μPa2 s (impact) and 128.9 dB re 1 μPa2 s (vibration). Bottlenose dolphins and harbor porpoises were not excluded from sites in the vicinity of impact piling or vibration piling; nevertheless, some small effects were detected. Bottlenose dolphins spent a reduced period of time in the vicinity of construction works during both impact and vibration piling. The probability of occurrence of both cetacean species was also slightly less during periods of vibration piling. This work provides developers and managers with the first evidence of the comparative effects of vibration and impact piling on small cetaceans, enabling more informed risk assessments, policy frameworks, and mitigation plans. In particular, our results emphasize the need for better understanding of noise levels and behavioral responses to vibration piling before recommending its use to mitigate impact piling.

Data on dolphin occurrence (from CPODs) for analyses of responses of dolphins to piling activity: 1. Data on dolphin occurrence (from CPODs) for analyses of responses of dolphins to piling activity (see Fig. 1, Fig. 4a & Fig. 7a,b,d,e). Filename = “dolphin presence & DPH12 CPOD data 2013-2014.txt” Fourteen columns = Location, Date, Julday, Presence, DPH12, Latitude, Longitude, Line_sight, Dist_impact, Year, Block, Impact, Vibration, Area. Julday is Julian day. Presence is the presence or absence (coded 1 or 0) of dolphins on each day of sampling (from 06:00 to 18:00). DPH12 is the number of hours within the 12-hour period (from 06:00 to 18:00) in which dolphins were detected. Line_sight indicates whether or not a location is within line of sight of the piling location (coded 1 or 0). Dist_impact is the minimum at-sea distance between each location and the piling location in meters. Block is the year concatenated with Julian day, used as the grouping factor for the GEEs (at the larger temporal scale). Impact is coded as two levels: 1 (impact piling), 0 (no impact piling). Vibration is coded as two levels: 1 (vibration piling), 0 (no vibration piling). Area is coded as two levels: 1 (within the Cromarty Firth), 0 (outside the Cromarty Firth).
dolphin presence & DPH12 CPOD data 2013-2014.txt

Data on porpoise occurrence (from CPODs) for analyses of responses of porpoises to piling activity: Data on porpoise occurrence (from CPODs) for analyses of responses of porpoises to piling activity (see Fig. 1, Fig. 4b & Fig. 7g,h,j,k). Filename = “porpoise presence & DPH12 CPOD data 2013-2014.txt” Fourteen columns = Location, Date, Julday, Presence, DPH12, Latitude, Longitude, Line_sight, Dist_impact, Year, Block, Impact, Vibration, Area. Julday is Julian day. Presence is the presence or absence (coded 1 or 0) of porpoises on each day of sampling (from 06:00 to 18:00). DPH12 is the number of hours within the 12-hour period (from 06:00 to 18:00) in which porpoises were detected. Line_sight indicates whether or not a location is within line of sight of the piling location (coded 1 or 0). Dist_impact is the minimum at-sea distance between each location and the piling location in meters. Block is the year concatenated with Julian day, used as the grouping factor for the GEEs (at the larger temporal scale). Impact is coded as two levels: 1 (impact piling), 0 (no impact piling). Vibration is coded as two levels: 1 (vibration piling), 0 (no vibration piling). Area is coded as two levels: 1 (within the Cromarty Firth), 0 (outside the Cromarty Firth).
porpoise presence & DPH12 CPOD data 2013-2014.txt

Data on dolphin encounter durations (from CPODs) for analyses of responses of dolphins to piling activity: Data on dolphin encounter durations (from CPODs) for analyses of responses of dolphins to piling activity (see Fig. 7c,f). Filename = “dolphin encounter durations CPOD data 2013-2014.txt” Fourteen columns = Location, Year, Durations, Date & Time, Hour, Latitude, Longitude, Line_sight, Dist_impact, Julday, Block, Impact, Vibration, Area. Durations is the duration (s) of each dolphin encounter that started between 06:00 to 18:00. Date & Time is the start time of each encounter. Hour is the hour in which each encounter started. Line_sight indicates whether or not a location is within line of sight of the piling location (coded 1 or 0). Dist_impact is the minimum at-sea distance between each location and the piling location in meters. Julday is Julian day. Block is the year concatenated with Julian day, used as the grouping factor for the GEEs (at the larger temporal scale). Impact is coded as two levels: 1 (impact piling), 0 (no impact piling). Vibration is coded as two levels: 1 (vibration piling), 0 (no vibration piling). Area is coded as two levels: 1 (within the Cromarty Firth), 0 (outside the Cromarty Firth).
dolphin encounter durations CPOD data 2013-2014.txt

Data on porpoise encounter durations (from CPODs) for analyses of responses of porpoises to piling activity: Data on porpoise encounter durations (from CPODs) for analyses of responses of porpoises to piling activity (see Fig. 7i,l). Filename = “porpoise encounter durations CPOD data 2013-2014.txt” Fourteen columns = Location, Year, Durations, Date & Time, Hour, Latitude, Longitude, Line_sight, Dist_impact, Julday, Block, Impact, Vibration, Area. Durations is the duration (s) of each porpoise encounter that started between 06:00 to 18:00. Date & Time is the start time of each encounter. Hour is the hour in which each encounter started. Line_sight indicates whether or not a location is within line of sight of the piling location (coded 1 or 0). Dist_impact is the minimum at-sea distance between each location and the piling location in meters. Julday is Julian day. Block is the year concatenated with Julian day, used as the grouping factor for the GEEs (at the larger temporal scale). Impact is coded as two levels: 1 (impact piling), 0 (no impact piling). Vibration is coded as two levels: 1 (vibration piling), 0 (no vibration piling). Area is coded as two levels: 1 (within the Cromarty Firth), 0 (outside the Cromarty Firth).
porpoise encounter durations CPOD data 2013-2014.txt

Data for analysis of daily broadband ambient noise levels at site 1: Data for analysis of daily broadband ambient noise levels at site 1 on days in which piling (impact, vibration, or both piling types) did or did not occur. Filename = “daily broadband noise levels.txt” Three columns = Date, Broadband, Piling Broadband is the averaged broadband (0.1-10 kHz) RMS ambient noise levels (dB re 1 µPa) Piling is coded as four levels: No, Impact, Vibration, Both
daily broadband noise levels.txt

Hourly broadband noise levels at site 1: Hourly broadband noise levels at site 1 during 10-min samples (see Fig. 3). Filename = “hourly broadband noise levels.txt” Three columns = Date & Time, Broadband, Piling Broadband is the averaged broadband (0.1-10 kHz) RMS ambient noise levels (dB re 1 µPa) Piling is coded as three levels: No, Impact, Vibration
hourly broadband noise levels.txt

Data on cetacean occurrence (from CPODs) for long-term monitoring site: Data on cetacean occurrence (from CPODs) for long-term monitoring site at the entrance to the Cromarty Firth during baseline period (2009-2013) and 2014 (see Fig. 5). Filename = “Sutors CPOD data 2009-2014.txt” Three columns = Date, Porpoise_DPH, Dolphin_DPH Porpoise_DPH is the number of hours in each day that porpoises were detected. Dolphin_DPH is the number of hours in each day that dolphins were detected.
Sutors CPOD data 2009-2014.txt

Data on bottlenose dolphin abundance estimates: Data on bottlenose dolphin abundance estimates in the Special Area of Conservation and the Cromarty Firth (see Fig. 6). Filename = “BND Abundance Estimates.txt” Five columns = Year, Area, Abundance_Estimate, Lower_95%CI, Upper_95%CI Area is coded as two levels: SAC, Cromarty Firth.
BND Abundance Estimates.txt

Details of each data package: Readme.txt file for data packages associated with paper on “Responses of bottlenose dolphins and harbor porpoises to impact and vibration piling noise during harbor construction” Data were collected by the University of Aberdeen and collaborators on a project funded through the UK Department of Energy & Climate Change Offshore Energy Strategic Environmental Assessment Programme using equipment previously purchased by DECC, Scottish Government, Oil and Gas UK, COWRIE and Moray Offshore Renewables Ltd.. Contact for queries is Isla Graham, i.graham@abdn.ac.uk

This work is licensed under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication license.