Group behavioral responses of juvenile common carp (Cyprinus carpio) to pulsed tonal stimuli in the presence of masking noise.

Acoustic behavioral deterrent systems are deployed to control range expansion of invasive species, and protect migratory fish from hazardous anthropogenic physical barriers. Installation sites (e.g. dams and weirs) are generally dominated by high-level background acoustic noise, a commonly neglected consideration when testing the effectiveness of acoustic behavioural devices. A laboratory study investigated the group behavioral responses of common carp (Cyrpinus carpio) to tonal stimuli under the presence or absence of a background masking noise. Preliminary data indicates a significant reduction in response under acoustically masked conditions. This has possible implications for future technological developments to ensure they are fit for purpose. Bespoke modifications may be required to ensure deterrents are effective under the background noise levels at proposed sites of interest.