Ocean Noise and Marine Mammals

• ISBN13: 9780309085366
• ISBN10: 0309085365
• Format: Paperback
• Copyright: 2003-05-01
• Publisher: Natl Academy Pr

Summary

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 the long- and short-term impacts of ocean noise on marine mammals.

Table of Contents

Executive Summary	1	(12)
Introduction	12	(15)
Statement of Task	16	(3)
Applications of the Sonar Equation to Biological Receivers	19	(7)
Structure of the Report	26	(1)
Sources of Sound in the Ocean and Long-Term Trends in Ocean Noise	27	(56)
Introduction	27	(2)
Natural Sources of Ocean Noise	29	(19)
Anthropogenic Contributions to Marine Noise	48	(26)
Long-Term Trends in Ocean Noise	74	(9)
Effects of Noise on Marine Mammals	83	(26)
Introduction	83	(1)
Hearing Capabilities of Marine Organisms	83	(6)
Acoustic Trauma in Marine Mammals	89	(1)
Effects of Marine Noise on Mammal Behavior	90	(6)
Masking of Acoustic Cues by Marine Noise	96	(6)
Habituation, Sensitization, and Tolerance of Marine Mammals to Marine Noise	102	(2)
Acoustically Induced Stress	104	(1)
New Research Tools to Understand Marine Mammal Behavior	105	(1)
Marine Ecosystem Impacts of Noise	106	(3)
Modeling and Databases of Noise in the Marine Environment	109	(18)
Introduction	109	(1)
Acoustic Modeling of the Marine Environment	109	(9)
Modeling the Effects of Noise on Marine Mammals	118	(4)
Databases	122	(4)
Summary	126	(1)
Findings and Recommendations	127	(8)
Sources of Noise in the Marine Environment	127	(2)
Marine Mammals and Ocean Noise	129	(2)
Ocean Noise Models	131	(1)
Overarching Recommendations	132	(3)
REFERENCES	135	(20)
APPENDIXES
A Committee and Staff Biographies	155	(4)
B Acronym List	159	(2)
C Examples of Underwater Acoustics Noise Models	161	(2)
D Research Recommendations from Previous NRC Reports (1994, 2000)	163	(10)
E Glossary of Terms	173	(16)
F Biological Terms	189