IS PASSIVE ACOUSTIC MONITORING DURING SEISMIC IS PASSIVE ACOUSTIC MONITORING DURING SEISMIC SURVEYS A VALUABLE TOOL FOR MITIGATION? SURVEYS A VALUABLE TOOL FOR MITIGATION?

Marine seismic airgun arrays are known to emit a frequency that overlaps with the vocalisation ranges of several marine mammal species. In the UK, legislation exists to minimise such acoustic disturbance. Gardline Environmental Ltd provides Marine Mammal Observers (MMOs) and Passive Acoustic Monitoring Systems (PAMS) to Oil and Gas companies for use during seismic surveys in the UK and International waters. Results from two case study surveys in areas with high cetacean sensitivity; waters West of Shetland (Figure 1A and 1B) and in the Moray Firth, highlight the strengths and limitations of PAMS. During both surveys the hydrophone array consisted of two related pairs of hydrophones (medium and high frequency) connected to IFAW’s Logger, Porpoise, Click and Whistle software.