Data from: Sperm whales reduce foraging effort during exposure to 1-2 kHz sonar and killer whale sounds

The time and energetic costs of behavioral responses to incidental and
experimental sonar exposures, as well as control stimuli, were quantified
using hidden state analysis of time series of acoustic and movement data
recorded by tags (DTAG) attached to 12 sperm whales (Physeter
macrocephalus) using suction cups. Behavioral state transition modeling
showed that tagged whales switched to a non-foraging, non-resting state
during both experimental transmissions of low-frequency active sonar from
an approaching vessel (LFAS; 1–2 kHz, source level 214 dB re 1 μPa m, four
tag records) and playbacks of potential predator (killer whale, Orcinus
orca) sounds broadcast at naturally occurring sound levels as a positive
control from a drifting boat (five tag records). Time spent in foraging
states and the probability of prey capture attempts were reduced during
these two types of exposures with little change in overall locomotion
activity, suggesting an effect on energy intake with no immediate
compensation. Whales switched to the active non-foraging state over
received sound pressure levels of 131–165 dB re 1 μPa during LFAS
exposure. In contrast, no changes in foraging behavior were detected in
response to experimental negative controls (no-sonar ship approach or
noise control playback) or to experimental medium-frequency active sonar
exposures (MFAS; 6–7 kHz, source level 199 re 1 μPa m, received sound
pressure level [SPL] = 73–158 dB re 1 μPa). Similarly, there was no
reduction in foraging effort for three whales exposed to incidental,
unidentified 4.7–5.1 kHz sonar signals received at lower levels (SPL =
89–133 dB re 1 μPa). These results demonstrate that similar to predation
risk, exposure to sonar can affect functional behaviors, and indicate that
increased perception of risk with higher source level or lower frequency
may modulate how sperm whales respond to anthropogenic sound.