The US Navy is deploying an underwater acoustic sensor system to detect and track marine mammals that might be approaching Navy testing ranges, enabling Navy personnel to avoid potentially injuring the animals.
Marine Mammal Monitoring (M3R) is adopted by the Naval Undersea Warfare Center (NUWC) Division, Keyport for use in a testing range in the northwest Salish Sea operated jointly by the US Navy and Canadian Forces Maritime Experimental & Test Ranges (CFMETR).
M3R utilizes a system of hydrophones and computer algorithms to detect, identify, and track marine mammals that might be approaching Navy testing ranges.
This enables the Navy to both protect marine mammals and improve its understanding of the animals’ behavior, said Dr. Dawn Grebner, a bioacoustician at NUWC Keyport.
The hope for the system is two-fold. One is to improve real-time monitoring during range events, and the second is to obtain a long-term understanding of the presence of these species in terms of when they move through our range areas, and how long they remain, in order to ultimately improve our management of the environment,
…he said.
Currently, marine mammal monitoring consists of visual sightings, meaning people are on the lookout for whales, porpoises, etc.
Multiple factors can negatively impact visual monitoring including weather conditions, sea states and whether or not the animals themselves spend enough time on the surface to be spotted in the first place.
Using a sophisticated combination of hydrophones and hyper-fast algorithms, M3R has the potential to negate those limitations and increase detection of marine mammals before they approach a range’s waters, the US Navy explained.
However, challenges may occur with implementing the M3R system due to the Salish Sea environment, because it is shallower than the ranges M3R was originally designed for, explained Grebner.
Some species-specific detection algorithms need to be developed for the animals in our area and added to the M3R’s database. That will allow us to quickly identify the mammals we hear. Also, since the water is shallower, localization accuracy may need to be recalibrated due to the difference sea floor depth can have on sound transmission.
