The 52 Hz call is identified in Navy hydrophone data
William Watkins of the Woods Hole Oceanographic Institution identifies a call at 52 Hz in US Navy hydrophone recordings - far higher than the calls of the great baleen whales around it. The same caller is subsequently tracked seasonally across the North Pacific, from off California toward the Aleutians, over hundreds and sometimes thousands of kilometres between recordings. It is the first demonstration that Cold War submarine-tracking infrastructure could follow an individual large whale across an ocean basin.
Observed — measured or witnessed, with the observation cited.
Subjects
- Passive Acoustic Monitoring Arrays · technology system · Global ocean basins · not located
Evidence
Partly verified — Core facts are sourced; some optional detail is deliberately absent.
SOSUS and its reuse for whale acoustics, including the 52 Hz call
SOSUS was installed by the US Navy from the mid-1950s as a network of seafloor hydrophone arrays across the Atlantic and Pacific, exploiting the deep sound channel so that low-frequency sound travels great distances; its mission was declassified in 1991. The 52 Hz call was first identified in 1989 by William Watkins of the Woods Hole Oceanographic Institution from Navy hydrophone data, and the same call was tracked seasonally across the North Pacific over hundreds to thousands of kilometres between recordings. V55 verification basis: retrieved in search summary; neither the Watkins publication nor a Navy declassification record was consulted.
Discovery of Sound in the Sea (University of Rhode Island); with the MIT Press Reader account of the SOSUS whale observatory · accessed 2026-08-08 · Partly verified
https://dosits.org/galleries/technology-gallery/locating-objects-by-listening-to-their-sounds/sound-surveillance-system-sosus/ ; https://thereader.mitpress.mit.edu/the-cold-wars-accidental-whale-observatory/
Recorded on Passive Acoustic Monitoring Arrays
- The 52 Hz call is identified in Navy hydrophone data
- The SOSUS mission is declassified
- Blue whales are found back at South Georgia
Related
Related because they share a subject in the Atlas — never because the text looks similar.