Electronic Supplementary Material
Exposure to seismic operations alters blue whale acoustic
communication
Biology Letters
Lucia Di Iorio1* & Christopher W. Clark2
1
Zoologisches Institut, Universität Zürich, Winterthurerstrasse 190, 8004 Zürich, Switzerland.
2
Bioacoustics Research Program, Laboratory of Ornithology, Cornell University, 159
Sapsucker Woods Rd., Ithaca, NY 14850, USA.
*
Correspondence: lucia.diiorio@zool.uzh.ch
Supplementary Materials and Methods
ESM_Fig. 1. Map of the St Lawrence estuary. Dark grey surface indicates the approximate area where the seismic
operations took place. Black circle indicates the position of the MARU recording area (distance between recording
units: 2km). The size of the circle does not represent the size of the MARU area. Abscissa numbers denote eastern
longitude and ordinate numbers denote northern latitude. Insertion represents the map of Canada.
ESM_Table 1. Summary of the sparker noise impinging on the recording units during the seismic
survey and of the resulting days selected for the analyses (‘seismic’, ‘no-seismic’).
Survey day
1
2
3
4
5
6
7
8
9
10
11
Sparker
pulses
n
y
y
y
y/n
n
n
n
y/n
y
n
Analyses
no-seismic
seismic
seismic
seismic
no-seismic
no-seismic
no-seismic
seismic
-
y= sparker pulses clearly recorded on all MARUs; n=no or only barely detectable sparker noise; y/n: sparker noise
not detectable on all recording units; dash indicating days not included in the analyses: on day 11 no visual
observations were conducted necessary to determine the number of whales present
Supplementary Results
ESM_Table 2. Results from the Wald-Wolfowitz Runs tests performed to test for the
independence of the daily 10min samples (N) used for call production analysis.
Survey day
N
Z
P
1
2
3
4
6
7
8
10
36
18
25
31
34
24
35
43
-1.44
-1.05
0.29
-0.98
-0.47
-1.74
-0.60
-1.55
0.15
0.3
0.8
0.33
0.64
0.08
0.55
0.12