The hear and now of Canadian redfish: response thresholds of <i>Sebastes fasciatus</i> to sound stimuli

Historical fishery collapses highlight the need to study life history traits and behaviours of commercially important species, and understanding the auditory capabilities of fish species is essential for assessing ecological interactions and responses to anthropogenic noise. The current study investigated neural and behavioural responses of Sebastes fasciatus (Acadian redfish) to tone bursts between 50 and 1000 Hz and complex sounds (boat noise, white noise, and broadband), presented at increasing decibel levels. Auditory evoked potential recordings revealed peak sensitivity to frequencies below 400 Hz, with the lowest threshold of 95 dB re 1uPa at 100 Hz. Lower frequencies of 50 to 500 Hz produced lower behavioural thresholds than 1000 Hz and complex sounds, but behavioural response typically occurred at higher intensities than AEP thresholds. These findings suggest selective auditory processing, showing S. fasciatus can detect lower frequencies before they elicit behavioural responses. Such findings provide valuable insights into the acoustic ecology of S. fasciatus and will help inform conservation efforts amid rising anthropogenic noise in marine environments.