Who makes the squeak – mice or rats? - briefly
Mice emit the characteristic high‑frequency squeak. Rats produce louder, lower‑pitched vocalizations such as chattering.
Who makes the squeak – mice or rats? - in detail
The high‑pitched sound heard in homes and laboratories is produced by rodents that use vocalizations for distress, mating, or territorial displays. Identification depends on anatomy, frequency range, and behavioral context.
Mice (Mus musculus) generate audible squeaks primarily when captured, threatened, or during courtship. Their calls occupy 4–12 kHz, last 30–200 ms, and reach amplitudes of 70–80 dB SPL at a meter. The sound is produced by rapid vibration of the laryngeal muscles, often accompanied by ultrasonic components above 20 kHz that are inaudible to humans.
Rats (Rattus norvegicus) emit two distinct vocal categories. The audible alarm squeal lies between 4–8 kHz, is longer (up to 500 ms), and can exceed 85 dB SPL. In addition, rats produce ultrasonic chirps (20–30 kHz) during social interactions, which humans cannot hear without equipment. The larger larynx and stronger respiratory muscles allow higher sound pressure.
Acoustic comparison
- Frequency range: mice 4–12 kHz; rats audible alarm 4–8 kHz, ultrasonic 20–30 kHz.
- Duration: mice 30–200 ms; rats alarm 100–500 ms.
- Amplitude: mice up to 80 dB SPL; rats up to 85 dB SPL.
- Context: mice – handling, mating; rats – predator threat, social hierarchy.
Field identification
- Use a spectrogram to distinguish the 4–8 kHz band (rat alarm) from the broader 4–12 kHz band (mouse distress).
- Observe behavior: rapid scurrying and freezing often accompany mouse squeaks; rats display aggressive posturing with louder, prolonged calls.
- Measure sound pressure; higher levels suggest rat origin.
In typical domestic settings, the audible squeak most frequently originates from mice, because their distress calls fall squarely within the human hearing range and occur during common disturbances such as trapping. Rat alarm calls are louder but less common in household encounters, as rats tend to avoid direct confrontation and rely more on ultrasonic communication.