Acoustic profiles of cetaceans: frequencies, intensities, ranges

From the subsonic to the ultrasonic

Cetaceans emit across an extraordinary acoustic range: from the song of the blue whale (10 Hz) to the ultrasonic clicks of the porpoise (140 kHz), spanning a breadth the human ear can perceive only in part. This table compares dominant frequencies, the ranges used, maximum intensities and documented detection ranges for 20 species.

Also worth listening to

Acoustics is central to cetaceans: sound library, vocal library by behaviour, senses (hearing) and anthropogenic ocean noise.

Source level and range: the orders of magnitude

The acoustic profile of a vocalisation is characterised by its frequency (in Hz), its intensity or source level (in dB re 1 µPa at 1 m) and its directivity. The sperm whale (Physeter macrocephalus) produces the most powerful clicks in the animal kingdom: up to 236 dB re 1 µPa (Møhl et al. 2003), thanks to its spermaceti organ, which acts as an acoustic lens.

The blue whale sings at 10-40 Hz, below the threshold of the human ear; its sounds can carry more than 1,000 km in the SOFAR channel. The harbour porpoise, conversely, emits at 130 kHz, highly directional ultrasound with a short range (~100 m), a strategy that makes it inaudible to killer whales, its predators.