The Hum of the Houseboats
People on houseboats in California were kept awake by a deep humming from the water, and suspected a secret military project.
What was reported
In the mid-1980s, people living on houseboats in Richardson Bay, Sausalito, began hearing a loud, low hum at night in summer, strong enough to make their hulls vibrate. Theories ranged from sewage pumps to secret military tests to visitors from space.
Scientists traced it to a fish: the plainfin midshipman, which comes into shallow water to breed in summer.
Explanations offered
Males hum to attract females by vibrating muscles against their swim bladders, and a chorus of them can drone loudly all night. Sausalito celebrated the discovery with a humming fish festival.
- When
- Mid-1980s
- Where
- Sausalito, California, USA
- Witnesses
- Houseboat residents
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.