NOAA’s Fisheries Service has issued regulations and a letter of authorization (LOA) to the U.S. Navy that includes measures to protect marine mammals while conducting research, development, test and evaluation activities and range expansion at the Naval Sea System Command Undersea Warfare Center Keyport Range Complex, in waters off the state of Washington.
The regulations require the Navy to implement protective measures to minimize effects on marine mammals.
The Navy requested authorization for the activities under the Marine Mammal Protection Act because while the high and mid-frequency sound generated by sonar, and other active acoustic sources, are not expected to harm marine mammals, they may affect the behavior of some marine mammals or cause a temporary loss of their hearing sensitivity.
Although they also utilize active sonar, the Navy’s activities conducted at the Keyport Range Complex are very different from the training activities addressed in other Navy rules. The active sonar and active acoustic sources are lower in volume than those used in training activities. The majority of the sound sources used in the Keyport Range Complex activities are high-frequency sonar sources, which have not been associated with marine mammal strandings and do not propagate sound energy as far as mid-frequency sonar.
NOAA’s Fisheries Service does not expect the Navy’s activities to result in injury of marine mammals. NOAA is requiring the Navy to use mitigation measures to minimize behavioral effects on and temporary hearing loss by marine mammals. NOAA’s Fisheries Service has made a determination that these activities would have only a negligible effect on the species or stocks involved.
Under the authorization, the Navy is required to follow mitigation measures to minimize possible effects on marine mammals, including:
– establishing marine mammal safety zones around each vessel using sonar and active acoustic sources and
– using Navy marine observers to spot marine mammals so that operations can be shut down if marine mammals are seen within designated safety zones.
These measures should eliminate the potential for injury, minimize behavioral effects, and significantly reduce the number of marine mammals exposed to levels of sound likely to cause temporary loss of hearing. Additionally, the regulations and authorization include an adaptive management component that requires the Navy and NOAA’s Fisheries Service to meet yearly to discuss new science and Navy research and development.
The Navy has developed a monitoring plan to help better understand how marine mammals respond to various levels of sound and to assess the effectiveness of mitigation measures. Implementation of this monitoring plan is a requirement of the regulations and the authorization, and its results will be reviewed annually as part of the adaptive management component. Additionally, the Navy has developed (with input from NOAA’s Fisheries Service) an integrated comprehensive monitoring plan to better prioritize monitoring goals and standardize data collection methods across all of their U.S. range complexes and study areas.
The Navy has been conducting research, development, test and evaluation activities, including the use of active sonar and active acoustic sources in the Keyport Range Complex for more than 60 years. The Navy provides research, development, test and evaluation activities and in-service support for expeditionary maneuver warfare, operations in extreme environments, and coastal operations.
This regulation, which will remain in effect for five years, governs the incidental take of marine mammals during the Navy’s research, development, test and evaluation activities, and includes required mitigation and monitoring measures. The letters of authorization, which are required for the Navy to legally conduct their activities, are issued annually, provided the Navy abides by the terms and conditions of the letter, submits the required annual reports, and shows their activities do not result in more significant effects to marine mammals than authorized.
Source: noaanews , April 13, 2011