NOAA 96-R128
Contact: Brian Gorman FOR IMMEDIATE RELEASE Scott Smullen 4/3/96
MARINE MAMMAL EXPERT TO MONITOR MIT EXPERIMENT IN PUGET
SOUND
Federal managers have proposed that an independent researcher ensure the safety of marine mammals during a three-week water flow study of Washington's Puget Sound this June, the National Marine Fisheries Service announced today.
Engineers from the Massachusetts Institute of Technology have applied for authorization to potentially disturb some marine mammals by using high frequency sound in a physical oceanography experiment to study tidal flows and the water-mixing process in Puget Soundþs Haro Strait, just south of Stuart Island.
The sounds from the MIT experiment are similar to those made by underwater electronic sonar devices used by commercial and recreational fishermen to locate schools of fish. The sound frequency and decibel level of the experiment may annoy nearby marine mammals, but should not damage any animalþs hearing or hamper its ability to search for food.
A qualified independent marine mammal researcher will monitor the MIT study for any change in animal behavior due to the experimentþs sound. As part of the authorization, the researcher will have the authority to modify or terminate the experiment, if the sound significantly alters the animalsþ normal behavior. An oversight committee consisting of local marine mammal scientists has been established to ensure protection for marine mammals. Harbor porpoise, Dall's porpoise, killer whales and harbor seals, none of which is an endangered or threatened species, normally occupy that area of Puget Sound.
According to the MIT application, the study will generate sound from five sound arrays moored between 10 and 200 meters below the water surface. Sound transmissions will occur for about four hours a day for three weeks. The fisheries service estimates that the MIT experiment will have a "zone of discomfort" of less than 750 feet for harbor porpoise and 1,300 feet for killer whales. In this zone, it may sound to the animals as loud as a rock concert does to humans. If they are uncomfortable, the animals are expected to move away from the area of the experiment.
The MIT Department of Engineering is planning to conduct the experiment between June 10 and July 5, to take advantage of the extreme ebb tides that occur in the area only twice a year. The winter alternative is unacceptable to the engineers, because weather conditions at that time would make operations difficult and marine mammal monitoring virtually impossible.
The fisheries service will accept comments through April 26, on the authorization to incidentally harass marine mammals during the MIT experiment. Comments may be sent to Chief, Marine Mammal Division, Office of Protected Resources, National Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-3225. Copies of the MIT application and programmatic environmental assessment are available by writing the same address.
The Marine Mammal Protection Act directs the fisheries service to allow, upon request, the incidental, but not intentional, harassment of marine mammals by U.S. citizens who engage in a specified activity (other than commercial fishing) within a specified geographical region if certain findings are made and regulations are issued. Permission may be granted if the fisheries service finds that the harassment will have a negligible impact on the species or stock, and monitoring and reporting of the activity are implemented.