Protecting Marine Resources

The coastal and sea areas of the Gulf of Alaska (GOA) are very important to the people of Alaska. These areas are home to a vast array of marine plants and animals, including whales, dolphins, seals, sea lions, fish, and birds. In addition, these areas are places where people make their living through subsistence or commercial use or for recreation purposes.

The marine areas in the GOA are also important to the U.S. Navy. The Gulf of Alaska is one of the only places in the northeastern Pacific Ocean where Armed Forces service men and women can come together to learn and practice the skills they require to respond to an emergency or threat.

Protecting the marine environment of the GOA is an important goal for the Navy. The Navy follows detailed programs to care for the environment and continues to improve these programs as they learn more about the ocean.

What is Sonar?

SOund NAvigation and Ranging uses underwater sound waves to locate submerged objects, such as submarines and mines. U.S. Navy ships rely on sonar to counter enemy submarines and mines in wartime, and to develop the skills needed to effectively detect and monitor submerged objects during peacetime. The Navy understands that the use of sonar may or may not have a negative effect on marine mammals under certain conditions. The scientific discussion of the impacts of human-generated underwater sound effects is ongoing. The Navy takes proactive protective measures to minimize possible effects to marine mammals and other ocean life.

The Navy’s Ongoing Protective and Conservation Measures

The Navy recognizes that sonar can affect marine mammals. While it is imperative for Navy personnel to train realistically to protect themselves and the nation from hostile threats, the Navy has developed a sophisticated set of procedures and tools to avoid harm to marine species. Every Navy ship and its crew follow these procedures and train thoroughly in their use. The Navy has been using these protective measures during anti-submarine warfare exercises since 2004. In addition, the Navy and National Marine Fisheries Service have developed further measures to protect marine mammals while the Navy trains under the National Defense Exemption from the Marine Mammal Protection Act.

The Navy’s marine mammal protective measures include:

Monitoring for marine species prior to training activities Prior to using active sonar, Navy personnel monitor the ocean area both visually and by using passive sonar to listen for marine mammal and sea turtle activity. (Many marine mammals are very vocal and add to the many sounds of the ocean environment.) During anti-submarine warfare training exercises, the Navy also uses aircraft to conduct continual visual surveys of the area.

Posting highly trained lookouts Qualification as a Navy shipboard lookout includes the completion of a Marine Species Awareness Training program, which is training supported by the National Marine Fisheries Service. This extensive training ensures that lookouts have the necessary skills to detect objects or activity in the water that could potentially be a marine mammal. Lookouts also are required to be knowledgeable in the details of marine species, the laws that govern their protection, and the Navy’s commitments to stewardship. At least five Navy lookouts are posted on each ship during mid-frequency active sonar use.

Establishing safety zones for marine species When engaged in anti-submarine warfare exercises, if a marine mammal is sighted within 1,000 yards of the sonar dome, the vessel will power down sonar, and do so again at 500 yards. If a marine mammal is visually detected to have entered within 200 yards of the sonar dome, the ship shuts down sonar use.

Conducting safe navigation While in transit, Navy vessel operators are alert at all times, use extreme caution, and take proper and effective action if there is a risk of collision with a marine animal.

Reporting sightings The Navy reports results of major exercises, including any marine mammal sightings, and coordinates with National Marine Fisheries Service in the event of a possible stranding.

Funding Research The underwater world of marine mammals is complicated. There is still much to learn about how marine mammals live, travel, and respond to human activities in the ocean. The Navy is the world leader in marine mammal research and provides $10-$14 million every year to universities, research institutions, federal laboratories, private companies, and independent researchers around the world to increase the understanding of marine mammal physiology and behavior. Much of this research is published in peer-reviewed scientific publications leading to independent verification and distribution of this new information. This research also helps the Navy identify issues of importance in determining underwater effects or lack of effects to marine species from Navy activities. The Navy also uses the results of these studies to develop new programs to protect marine mammals while training at sea.

Preventing Marine Mammal Strandings

Reports of marine mammal strandings can be traced back to ancient Greece. Several factors can contribute to the occurrence of stranding events, including both natural causes and human-influenced causes.

To minimize the potential for a stranding event, the Navy takes precautions when scheduling and conducting training activities to avoid the combination of certain factors that could potentially contribute to marine mammal strandings. These factors include:

• Presence of species sensitive to sonar (e.g., beaked whales)
• Rapid change in bathymetry
• Multiple ships simultaneously operating mid-frequency active sonar in close proximity over an extended period of time
• Narrow channel or steep embayment with limited egress for marine mammals
• History of significant surface ducting

Worldwide naval use of active sonar has been correlated with five marine mammal stranding events from 1996 to 2006, with a total of 51 stranded animals and 37 mortalities. This is an average of five marine mammals stranded per year. To put this in perspective, more than 600,000 marine mammals are killed as by-catch each year by commercial fishing interests worldwide. While there have been marine mammal stranging mortalities potentially associated with mid-frequency active sonar, the causes are still unknown and being investigated.

Putting the Latest Science and Technology to Practical Use

The National Environmental Policy Act process gives the Navy an opportunity to review and assess its activities, ensuring that the benefits of recent scientific and technological advances are applied toward analyzing potential environmental effects. As part of this process, scientists will compile and analyze all currently available data and research with a focus on understanding species distribution, abundance, and movement patterns, as well as potential effects from underwater activities. Examples of available information include:

Marine Resource Assessments Comprehensive, compiled reviews of marine species distribution reports, and sighting and survey data, as well as peer-reviewed literature and National Marine Fisheries Service reports, including stock assessments and recovery plans. These assessments are specific to the GOA and vicinity.

Density Estimates Estimates of marine species abundance in the GOA study area based on analysis of shipboard and aerial survey data.

Scientific Literature and Study Results Results of research focused on hearing and diving physiology, behavioral responses to human-generated sound, and understanding the potential effects of sound in the water.

Sound Propagation and Effects Modeling Tools to model how sound propagates (i.e., travels) through water and whether this propagation could lead to any potential effects or lack of effects to different marine species.

For More Information

To learn more about the science of sound in the water, visit the Discovery of Sound in the Sea Web site, developed by the University of Rhode Island, at www.dosits.org.

To learn more about marine mammals and sonar and the Navy’s ocean stewardship programs, visit www.navy.mil/oceans/.