A Sound System to Keep Deer Away from Railway Tracks in Japan

In Japan, collisions between trains and deer are a growing concern, causing delays, material damage, and putting both animals and passengers at risk. To address this issue, the Railway Technical Research Institute (RTRI) has developed a clever, wildlife-friendly sound system.

The concept: alert and deter

Deer naturally emit a snort to warn others of imminent danger. Building on this behavior, RTRI researchers created an audio sequence combining:

• a 3-second deer snort;
• followed by 20 seconds of dog barking — a predator deer instinctively fear.

The goal is twofold: first to capture the deer’s attention (alert), then to make them flee (deterrent).

Field testing: onboard device and results

Tests were conducted in winter, especially at night, when deer are most commonly seen near train tracks.

Comparative trials revealed:

• without sound: 90 deer sightings over 660 km (approx. 13.5 sightings per 100 km);
• with sound: 82 sightings over 1,100 km (approx. 7.4 sightings per 100 km).

This indicates a reduction of about 45% in deer sightings in areas where the sound was played.

Why this method works

This approach leverages two key behavioral responses:

• the snort captures attention and triggers alertness among deer;
• dog barking is perceived as a threat, prompting rapid flight.

Using natural sounds — instead of artificial signals like sirens — prevents animals from becoming desensitized, ensuring the system remains effective over time.

Context and deployment

Previous methods such as fences, barriers, ultrasonic repellents or speed adjustments proved insufficient against growing deer populations.

This sound system is designed to be triggered only as the train approaches, to prevent overexposure and habituation among animals.

According to the World Economic Forum (2018), practical deployment was being considered for early 2019.

Conclusion

This innovation developed by the RTRI, tested in real conditions, has shown a significant 45% drop in deer sightings near tracks. It is not a gimmick or speculation, but a credible and promising technology to enhance railway safety while protecting wildlife.

Does this kind of initiative spark your interest? Do you think similar measures could help protect other animals, or should this approach be adapted to local species?