How does a rat scream in a trap? - briefly
Rats produce high‑frequency ultrasonic vocalizations when caught, which manifest to human ears as a sharp squeal. The sound originates from rapid laryngeal muscle contraction and forced airflow through the vocal cords under stress.
How does a rat scream in a trap? - in detail
Rats emit a high‑frequency, broadband squeal when caught, produced by rapid vibration of the vocal folds under intense muscular contraction. The sound originates from the laryngeal muscles, which close the glottis and force air through a narrowed passage, generating pressure that excites the vocal cords. Stress hormones such as adrenaline heighten muscle tension, increasing the amplitude of the emission.
Acoustic characteristics of the distress call include:
- Frequency range: 5 kHz – 30 kHz, with peak energy typically around 10 kHz.
- Duration: 0.2 s – 1.5 s per burst, often repeated in series.
- Amplitude: up to 90 dB SPL at 10 cm distance, sufficient to be detected by human hearing and specialized ultrasonic equipment.
Trap design influences the vocal response. Confinement that restricts movement, sharp edges that cause tissue injury, and sudden pressure changes all amplify the signal. Live‑catch cages produce longer, repeated calls compared with snap traps, where the rapid fatal injury truncates the emission.
Detection of the scream provides a reliable indicator for monitoring rodent activity. Ultrasonic detectors calibrated to the described frequency band can quantify capture events, enabling objective assessment of trap efficacy and population density.