February 18, 2020 — The following was released by NOAA Fisheries:
Two passive acoustic data collection efforts are underway in the Gulf of Maine to gather information on North Atlantic right whales. One will deploy fixed archival-acoustic recorders mounted on the ocean bottom for a specific period of time. The other will use autonomous underwater vehicles called gliders, equipped to record acoustic information and report it back in near real-time.
“Real time monitoring provides the opportunity for direct conservation action through alerting vessels to the presence of endangered whales and to slow down to avoid striking the whales, while archival monitoring helps build a long-term 24/7 picture of their presence,” said Sofie Van Parijs, who leads the Passive Acoustic Research Group at the Northeast Fisheries Science Center.
“These new efforts will support routine passive acoustic monitoring of North Atlantic right whales and other baleen whale species throughout priority areas, and improve our understanding of changes in their movement patterns,” she said.
Right whales have changed their historic migration patterns in recent years, and tracking them is a difficult task.
Like most whales, this species does not spend much time on the ocean surface where they can be seen by researchers during aerial or ship-based surveys. Sound is the whale’s primary means of communicating, so if they are present in an area, they are probably making sounds. Underwater microphones can detect those sounds and even report back to researchers in near real-time.
Passive acoustic monitoring – detecting and recording sounds, in this case underwater – offers scientists another tool for learning about whale behavior and migration patterns. Advanced underwater microphones or hydrophones and autonomous underwater vehicles can detect and record those sounds. Computer programs help differentiate species and indicate time, direction and location.
These instruments can remain in the water continuously for months at a time. Along with visual sightings made from ships and aircraft, the sound recordings are revealing information about where and when whales of various species are present.