DOI: 10.5061/dryad.40nv6
title: Data from: Fine-scale movement responses of free-ranging harbour porpoises to capture, tagging, and short-term noise pulses from a single airgun

description: Knowledge about the impact of anthropogenic disturbances on the
 behavioural responses of cetaceans is constrained by lack of data on
 fine-scale movements of individuals. We equipped five free-ranging harbour
 porpoises (Phocoena phocoena) with high-resolution location and dive
 loggers and exposed them to a single 10 in3 underwater airgun producing
 high-intensity noise pulses (2−3 second intervals) for one minute. All
 five porpoises responded to capture and tagging with longer, faster and
 more directed movements as well as with shorter, shallower, less wiggly
 dives immediately after release, with natural behaviour resumed in ≤24
 hours. When we exposed porpoises to airgun pulses at ranges of 420−690 m
 with noise level estimates of 135−147 dB re 1µPa2s (SEL), one individual
 displayed rapid and directed movements away from the exposure site and two
 individuals used shorter and shallower dives compared to natural behaviour
 immediately after exposure. Noise-induced movement typically lasted for ≤8
 hours with an additional 24-hour recovery period until natural behaviour
 was resumed. The remaining individuals did not show any quantifiable
 responses to the noise exposure. Changes in natural behaviour following
 anthropogenic disturbances may reduce feeding opportunities and evaluating
 potential population-level consequences should be a priority research
 area.
description: Exposed porpoise GPS
 dataThis is the full dataset
 collected by GPS tags fitted on four harbor porpoise individuals. Large
 positional errors were removed as described in the article. The data also
 contains the calculated horizontal movement parameters and distance
 variables to produce figure 1 in the main article and the figures in the
 Supplementary material. The data contains 10 variables: “id” gives the
 name of the harbor porpoise individual “datetime” gives the date and time
 of the GPS location columns “x” and “y” are the coordinates of the GPS
 location in the projection CRS("+proj=utm +zone=32 +ellps=intl
 +towgs84=-87,-98,-121,0,0,0,0 +units=m +no_defs") “steplength” is the
 Euclidian distance (m) between GPS locations “speed” is the speed (m/sec)
 between GPS locations “turing_angle” is the turning angle (degrees)
 between GPS locations “hour_since_release” is the time (hours) since the
 individual was released into the water after GPS tagging
 “dist_to_exposure_site” is the Euclidian distance (m) of the individual
 porpoise relative to the airgun exposure site “dist_to_release_site” is
 the Euclidian distance (m) of the individual porpoise relative to the GPS
 tagging and release siteraw_data_horizontal_movements_160503.txtExposed porpoise dive dataThis is the full dataset collected by dive-loggers fitted on four harbor porpoise individuals. Impossible values were removed as described in the article. It is the underlying data used to produce figures in the Supplementary material and contains 6 variables: “id” gives the name of the harbor porpoise individual “datetime” gives the date and time of the start of each dive “dive_duration” gives the difference in time (sec) between the start and end of each dive “max_depth” provides the maximum depth (m) reached during each dive “wiggliness” provides the sum of absolute depth differences (m) while at the bottom of each dive; measure of amount of “wiggling” while at bottom “post_dive_duration” provides the time (sec) spent at the surface after each diveraw_data_vertical_movements_160503.txtresidual_data_horizontal_movementsContains the residuals of the GAM analyses on the horizontal movement data, which was used in the piecewise regression analyses. It is the underlying data used to produce figure 3 in the main article and contains 5 variables: “id” gives the name of the harbor porpoise individual “hour_since_release” is the time (hours) since the individual was released into the water after GPS tagging “residuals_steplength” are the residuals of the Euclidian distance (m) between GPS locations “residuals_speed” are the residuals of the speed (m/sec) between GPS locations “residuals_turing_angle” are the residuals of the turning angle (degrees) between GPS locationsresidual_data_vertical_movementsContains the residuals of the GAM analyses on the vertical movement data, which was used in the piecewise regression analyses. It is the underlying data used to produce figure 4 in the main article and contains 6 variables: “id” gives the name of the harbor porpoise individual “hour_since_release” is the time (hours) since the individual was released into the water after GPS tagging “dive_duration” are the residuals of the difference in time (sec) between the start and end of each dive “max_depth” are the residuals of the maximum depth (m) reached during each dive “wiggliness” are the residuals of the sum of absolute depth differences (m) while at the bottom of each dive “post_dive_duration” are the residuals of the time (sec) spent at the surface after each diveR-codeThe file contains the R-code for the piecewise linear regression analyses and model selection used to assess capture/tagging and airgun noise-induced movement responses in harbour porpoises