Most young people can detect a 20,000 Hz sound. Dogs leave us in the halfpenny place when it comes to sound detection. You might expect that hedgehogs, rummaging for creepy-crawlies in leaf-litter, would have little use for high-pitched noise detection. The main enemy is the motor vehicle; hedgehogs, trying to cross roads, are squashed to death under the wheels of cars. A high-pitched sound-emitting device, attached to a vehicle, might warn hedgehogs of impending danger, without its noise disturbing people.

Source: Irish Examiner March 26, 2026 18:00 UTC