Basic understandings of whale bioacoustics: Potential impacts of man-made sounds from oceanographic research

Abstract

The recent increased public awareness and concern over the potential impact of acoustic sources for oceanographic research, particularly the source for the Acoustic Thermometry of Ocean Climate (ATOC) study, has raised the difficult issue of assessing both short-term and long-term effects. A baseline study in Kauai, HI has been underway for two seasons as part of the Marine Mammal Research Program associated with ATOC. This research specifically addresses the questions related to short-term (<4 months), small scale (<30-km radius zone of influence) issues using traditional visual and acoustic field methods. This includes shore-based and aerial observations, passive hydrophone array tracking, and aerial survey methods. These efforts, conducted prior to any operation of an ATOC source, provide a baseline measure of the level of short-term impact under ‘‘normal’’ conditions off Kauai, where normal includes regular exposure to noise from small craft, ships, helicopters, and airplanes. Potential long-term impact is addressed through statewide aerial surveys and through integration of the inter- and intra-seasonal variability of whale behaviors and distributions. Results of the Kauai research will be presented and discussed in terms of baseline impact and the need for standards.