# At least one of the sounds, most often the Bloop, was made by a large animal, known or unknown.

> Disputed: At least one of the sounds, most often the Bloop, was made by a large animal, known or unknown.

Source: https://mysteriesdept.com/mysteries/noaa-ocean-sounds/answers/ANS0D9C7F024MPX/at-least-one-of-the-sounds-most-often-the-bloop-was-made-by  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Questions](https://mysteriesdept.com/questions)[Bloop and NOAA's unexplained ocean sounds](https://mysteriesdept.com/mysteries/noaa-ocean-sounds)[What made the loud unidentified sounds recorded by NOAA's Pacific hydrophones in the 1990s?](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/questions/QST0D9C7CA41BJB/what-made-the-loud-unidentified-sounds-recorded-by-noaas)Answer

Answer · Bloop and NOAA's unexplained ocean sounds

# At least one of the sounds, most often the Bloop, was made by a large animal, known or unknown.

At least one of the sounds, most often the Bloop, was made by a large animal, known or unknown.

**Disputed** Answers **1** questionPublished0

## Where it stands

**Disputed** One piece of evidence for, two against. It needs two reviews to be accepted.

## What it predicts

- The sound has the harmonic structure and repetition of animal calls.
- Source levels are within the physiological range of a living animal of plausible size.

## What would rule it out

- A source level far beyond any animal, or a match to an ice or volcanic signal recorded with the source observed.

## Evidence 1 for · 2 against

[The Bloop's rising frequency reminded biologists of animal calls.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7F7W7KDX/the-bloops-rising-frequency-reminded-biologists-of-animal)

Speculative

FOR

[Its spectrogram resembles icequakes recorded in the Scotia Sea.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7FQG2BND/its-spectrogram-resembles-icequakes-recorded-in-the-scotia)

Supported

AGAINST

[The Bloop was far louder than any known animal; Lobel doubted cephalopods could make such a sound.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7FFP2MW8/the-bloop-was-far-louder-than-any-known-animal-lobel-doubted)

Supported

AGAINST

## The questions it answers

[What made the loud unidentified sounds recorded by NOAA's Pacific hydrophones in the 1990s?](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/questions/QST0D9C7CA41BJB/what-made-the-loud-unidentified-sounds-recorded-by-noaas)

Most likelyAll of them are natural geophysical or cryogenic sounds (icequakes, grounding icebergs, volcanic eruptions…

## Cite it

```
Mysteries Department. (2026). At least one of the sounds, most often the Bloop, was made by a large animal, known or unknown. [Answer ANS0D9C7F024MPX]. https://mysteriesdept.com/r/ANS0D9C7F024MPX
```

Key

**ANS** 0D9C7F024MPX

Kind

Answer · hypothesis

Origin

Published

Version

1

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