Center for Marine Biodiversity and Conservation

Sound propagation models were developed for modally dispersed seismic shots to determine range to a seismic source from two High-frequency Acoustic Recording Packages (HARPs) deployed on the continental slope break north-northwest of Point Barrow, Alaska in the fall of 2007.Received levels at the HARPs had an average received sound level of 112.8 dB rms. These received level measurements coincide with levels that have shown to elicit behavioral responses in bowhead whales, and raise concerns about how seismic activities may potentially impact marine mammals across large spatial scales and international maritime boundaries. Although guidelines have been established to reduce such impacts, current mitigation measures show considerable variation between countries and do not take into account the transboundary nature of sound in the ocean. To provide an international framework for the regulation of seismic surveys in the Arctic, a better understanding of how sound propagates in a changing Arctic environment, in addition to how the cumulative impacts of multiple seismic activities may influence ambient noise levels across large spatial scales is needed. A collaborative approach to management, mitigation, and research is essential to provide effective protection for marine mammals as a result of increased international and multi-industry interest in the Arctic and its natural resources.