Ocean Noise and Marine Mammals

For the 119 species of marine mammals, as well as for some other aquatic animals, sound is the primary means of learning about the environment and of communicating, navigating, and foraging. The possibility that human-generated noise could harm marine mammals or significantly interfere with their normal activities is an issue of increasing concern. Noise and its potential impacts have been regulated since the passage of the Marine Mammal Protection Act of 1972. Public awareness of the issue escalated in 1990s when researchers began using high-intensity sound to measure ocean climate changes. More recently, the stranding of beaked whales in proximity to Navy sonar use has again put the issue in the spotlight. Ocean Noise and Marine Mammals reviews sources of noise in the ocean environment, what is known of the responses of marine mammals to acoustic disturbance, and what models exist for describing ocean noise and marine mammal responses. Recommendations are made for future data gathering efforts, studies of marine mammal behavior and physiology, and modeling efforts necessary to determine what the long- and short-term impacts of ocean noise on marine mammals. Table of Contents Front Matter Executive Summary 1. Introduction 2. Sources of Sound in the Ocean and Long-Term Trends in Ocean Noise 3. Effects of Noise on Marine Mammals 4. Modeling and Databases of Noise in the Marine Environment 5. Findings and Recommendations References Appendix A: Committee and Staff Biographies Appendix B: Acronym List Appendix C: Examples of Underwater Acoustic Noise Models Appendix D: Research Recommendations from Previous NRC Reports Appendix E: Glossary of Terms Appendix F: Biological Terms Color Plates