Figure 2
From: Disturbance-specific social responses in long-finned pilot whales, Globicephala melas
Schematic representation of experimental approach (not drawn to scale).
Observation vessel (29 m): aimed to maintain distance of 100–400 m to the focal group, representing a consistent factor in all experiment conditions; Source vessel (55 m): direct approach and signal transmission from 6–8 km at 3–4 ms−1. At 1 km distance, vessel course is locked. Approach and transmission continued until ~5 minutes after passing the focal group (closest approach: 40–560 m; mean = 250 m13;). Sonar: transmission of sonar signals. No-sonar control (ctrl): no transmission; Tagging vessel: consistent close approach aiming to apply a tag; Killer whale playback vessel: stationary, in front and to the side of focal group travel path (2400 ± 943 m27;). KW: transmission of killer whale vocalisations. Noise ctrl: transmission of broadband noise.
