The 52 Hz call is identified in Navy hydrophone data

Assembled from 15 blocks · 1 evidence · 10 related

1. Story
2. 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.
3. Knowledge
4. Passive Acoustic Monitoring Arrays
5. The 52 Hz call is identified in Navy hydrophone data
6. Connections
7. Passive Acoustic Monitoring Arrays
8. Antarctic Summer Feeding Migration
9. IWC Southern Ocean Research Partnership
10. The 52 Hz call is identified in Navy hydrophone data
11. The SOSUS mission is declassified
12. Blue whale song frequencies are observed falling worldwide
13. Blue whales are found back at South Georgia
14. Evidence
15. 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.