Can snakes hear you scream?

Sight and taste are the main ways snakes sense their environment, but hearing is a more important element than previously thought.

Snakes can feel sound vibrations through the ground (called tactile sensing) but new research shows that they can also hear sounds through the air, like we can, and different species respond in different ways.

Australia is a country well known for its variety of impressive and mostly lethal snakes so it seems apt that the new research has been published by a team at the University of Queensland.

The team tested 19 different snakes from seven species in a soundproof room where they were able to move freely. Each snake was tested individually and was played three consecutive airborne sounds from frequencies 1–150Hz,150–300Hz and 300–450Hz (the human voice is 100–250Hz).

There were clearly different responses from different species. Woma pythons moved more in response to sound and actually approached the sound source, raising the front third of their body in a manner that suggested curiosity.

Death adders, taipans and brown snakes tended to move away from the sound. Death adders are ambush predators and are unable to move quickly so it makes sense that they might move away from the source of the sound. Brown snakes and taipans are active foragers that rapidly pursue their prey during the day. They may be vulnerable to predators and be more cautious in response to sound.

The study showed that snakes were only able to hear low frequencies, roughly below the 600Hz mark, whereas humans can hear a much wider range. However, it’s likely that they can hear us speaking.

The frequency of the human voice is about 100–250Hz and the study included sounds at these frequencies and at the amplitude of a loud voice.

The snakes responded to these sounds – many quite significantly – so it’s safe to say they can hear people speaking loudly.