Fig. 5

Ship transit event with acoustic presence of narwhals. Canadian Coast Guard Icebreaker, Terry Fox on Oct 4, 2018, traveling at speed over ground 14 knots past the recording location at the eastern entrance to Eclipse Sound. Long-term spectral average (LTSA) plot showing ship distance from the recording location, time with respect to closest point of approach (CPA), and received sound pressure spectrum levels (color bar) for frequencies from 20–20,000 Hz during a 4-h ship transit window.