COMPARATIVE REVIEW OF MARINE MAMMAL GUIDANCE IMPLEMENTED DURING NAVAL EXERCISES

摘要

The guidance currently in use by navies to mitigate potential impacts from sonar on marine mammals throughout the world varies in parameters such as the EZ radius, the marine mammal species included in mitigation, and delay/shut-down procedures. Relatively few aspects of current mitigation have a firm scientific basis and proven efficacy in the field, and there remains a total lack of effective mitigation during night and adverse weather. Recent US court cases have been successful in highlighting a number of these inadequacies. This review highlights a number of shortcomings in the existing mitigation guidance and makes recommendations towards improved standards of protection. Marine mammal mitigation measures should be utilised during all naval exercises by all nations. Where a number of nations are exercising together, the highest level of protection should be maintained. Area closures and avoidance of key marine mammal habitat remain the most effective and precautionary measure for active sonar and other intense naval sound sources. Areas of importance for marine mammals should be explicitly identified and such measures implemented. Given the particular sensitivity of beaked whales to mid-frequency active sonar, all navies have a responsibility to conduct their activities in a way that limits potential impacts on those species.