Title: Taking and Importing Marine Mammals: Taking Marine Mammals Incidental to U.S. Navy Operations of Surveillance Towed Array Sensor System Low Frequency Active Sonar
Docket ID: NOAA-HQ-2017-0037
Agency: DOC-NOAA, National Marine Fisheries Service
Comments Close: May 30, 2017
The National Marine Fisheries Service has received a request from the U.S. Navy for authorization to take marine mammals, by harassment, incidental to conducting operations of Surveillance Towed Array Sensor System Low Frequency Active sonar in areas of the world's oceans (with the exception of Arctic and Antarctic waters and certain geographic restrictions), from August 15, 2017, through August 14, 2022. The Navy's activities are considered military readiness activities in accordance with the Marine Mammal Protection Act. In accordance with the Marine Mammal Protection Act, the National Marine Fisheries Service is requesting comments on its proposal to issue regulations to govern the incidental take of marine mammals by Level B harassment during the Navy's activities.
The Marine Mammal Protection Act of 1972 allows, upon request, the incidental take of marine mammals by U.S. citizens if certain findings are made and regulations are issued, or if the taking is limited to harassment. Under the Marine Mammal Protection Act, harassment is defined as "any act of pursuit, torment or annoyance which has the potential to either: a. injure a marine mammal in the wild, or b. disturb a marine mammal by causing disruption of behavioral patterns..." This proposed regulation involves both Level A and Level B harassment; Level A harassment has the potential to injure a marine mammal or marine mammal stock in the wild, whereas Level B harassment has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, but does not have the potential to injure a marine mammal or marine mammal stock in the wild.
This will be the National Marine Fisheries' Service's fourth rule making for the Surveillance Towed Array Sensor System Low Frequency Active sonar operations under the Marine Mammal Protection Act.
For this fourth rule making, the Navy is proposing to conduct the same types of sonar activities in the proposed rulemaking as they have conducted over the past fourteen years in the previous three rule makings with the exceptions of updating the LFA sonar duty cycle from 20 percent to 7.5-10 percent based on historical data. In addition, the Navy is proposing a Preferred Alternative (Alternative 2) in their DSEIS that would transmit a maximum number of 255 hours of LFA sonar per vessel per year, as opposed to the previously authorized 432 hours of LFA sonar per vessel per year.
The Navy states that these training, testing, and routine military activities may expose some of the marine mammals present in the operational areas to sound from low-frequency active sonar sources. Because marine mammals may be harassed due to noise disturbance incidental to the use of Surveillance Towed Array Sensor System Low Frequency Active (SURTASS) Low Frequency Active sonar during training, testing, and routine military operations, the Navy utilized the most recent National Marine Fisheries Service acoustic Technical Guidance (NMFS 2016) to analyze potential takes of marine mammals. The Navy requests authorization to take individuals of 104 species of marine mammals by Level B Harassment. Further, the Navy states that the probability of taking marine mammals by Level A Harassment is less than 0.001 percent. However, because the probability is not zero, the Navy has included a small number of Level A harassment in its authorization request as a precautionary measure.
The Navy will also be including a suite of proposed mitigation measures for marine mammal take that could potentially be affected during SURTASS Low Frequency Active sonar operations.
Contributor: PhD Candidate, Aquatic and Fishery Sciences