Aug 7, 2026 · 36 min
Sweden mistakes herring for Soviet submarines
Red Herring
The story shows how secrecy, fear, and institutional assumptions can turn ambiguous evidence into an apparent act of war.
- 1Swedish forces spent years hunting phantom submarines after repeated sounds and sightings near military bases and coastlines.
- 2Researchers Magnus Wahlberg and Håkan Westerberg traced the Navy’s classified “typical sound” to enormous schools of herring.
- 3Secrecy and hierarchy kept sonar evidence from receiving the open scientific scrutiny that could have resolved the mystery sooner.
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A hydrophone near a fishing trap records thousands of herring producing the Navy’s supposedly mechanical “typical sound.”
The brief
In Cold War Sweden, repeated underwater sounds and sightings near military bases created a national security crisis, with the Soviet Union cast as the likely culprit.
The Navy expanded surveillance, deployed nets, sonar, helicopters, and depth charges, yet the suspected submarines remained elusive as public fear and political pressure grew.
Marine researchers Magnus Wahlberg and Håkan Westerberg were finally allowed to hear the classified “typical sound” and suspected it was biological rather than mechanical.
Experiments showed individual herring did not match the recording, but a hydrophone near a fishing trap captured thousands of stressed fish producing the unmistakable sound.
In 1999, Sweden’s Navy concluded the alarms had been caused by herring, revealing how secrecy, hierarchy, and military assumptions had overwhelmed scientific skepticism.
Ola TunanderMentioned
Boris YeltsinListen to the full episode and explore every guest, topic, and moment on PodLume.