Studies – Acoustic and optical wildlife warning devices

The study conducted by the University of Natural Resources and Life Sciences, Vienna (BOKU)

The study by the University of Natural Resources and Life Sciences, Vienna (BOKU) shows that wildlife warning systems can significantly reduce the number of wildlife collisions on Tyrolean roads. Particularly effective is the combination of reflectors and acoustic wildlife warning devices, which according to the study can reduce wildlife collisions by up to 70%. Proper selection, installation, and maintenance of the systems are crucial for their success.

The objective is to prevent wild animals from crossing roads and thereby reduce accidents, animal suffering, and economic damage.

Key Findings

• Since 2014, the Province of Tyrol, hunting associations, and road maintenance authorities have been working together on the project. Funding is mainly provided by the Province of Tyrol and hunting associations.
• The average economic damage per accident amounts to approximately €2,500.
• Reflectors and acoustic warning systems are used to reduce wildlife collisions.
• The study conducted by Dr. Wolfgang Steiner from University of Natural Resources and Life Sciences, Vienna in the Austrian provinces of Burgenland, Lower Austria, and Styria demonstrated:
  • approx. 40% fewer wildlife collisions when using reflectors
  • up to 70% fewer wildlife collisions when combining reflectors with acoustic warning systems
• Special emphasis was placed on the acoustic warning system from WEGU-GFT, which was preferred because of its superior durability (welded housing and capacitor technology instead of batteries).
• The report highlights that every road section must be individually evaluated according to factors such as topography, vegetation, wildlife crossings, and feeding areas to ensure effectiveness.
• In 2018, the focus was on optimizing existing road sections, maintenance, and evaluating system effectiveness. Some roads showed significant improvements, while others required upgrades or adjustments.
• A guideline was developed for the future to standardize the selection, installation, and inspection of wildlife warning systems.

Along several road sections in Tyrol, the use of reflectors and the combination of reflectors with acoustic wildlife warning devices significantly reduced wildlife collisions.

The WiConNET Study (Canton of Zurich, Switzerland)

The WiConNET study evaluates active wildlife warning systems much more positively than passive wildlife reflectors.

Key Findings Regarding WEGU

• According to several studies, passive wildlife reflectors alone often show no clearly measurable effect on animal behavior or the number of wildlife collisions.
• Active acoustic systems such as the WEGU “Day and Night” wildlife warning devices are described as significantly more effective.
• In a German railway project on the Weiden–Nuremberg line, WEGU systems reportedly reduced wildlife collisions by approximately 75%, according to DB Regio.
• On Austrian test routes examined within the WiConNET study, reductions of up to 80% fewer wildlife fatalities were recorded.
• At the same time, the study emphasizes that effectiveness strongly depends on proper planning, including:
  • site selection
  • vegetation management
  • wildlife crossing patterns
  • maintenance
  • correct installation

Conclusion of the Study

According to WiConNET, active acoustic wildlife warning systems such as WEGU deliver significantly better results than reflector-only solutions and can substantially reduce wildlife collisions — provided that the systems are professionally planned, installed, and maintained.

Advantages of Acoustic Wildlife Warning Systems

1. Overcoming the Habituation Effect

A major problem with many systems is that animals become accustomed to recurring sounds. However, the acoustic wildlife warning device uses variable frequency ranges. Since the sound does not always remain identical, animals continue to perceive it as a potential danger or at least as an unfamiliar disturbance signal requiring caution.

2. Significant Behavioral Changes in Animals

Evaluations, often supported by wildlife cameras, show significant changes in animal behavior:

• Stop reaction: animals stop at the forest edge.
• Avoidance behavior: animals avoid crossing the roadway during active warning phases.
• Statistics: in test areas, wildlife collisions decreased significantly, often by double-digit percentages.

3. Independence from Environmental Factors

Conventional optical warning systems (reflectors) often fail due to dirt, unfavorable angles, or fog. Acoustic signals, however, penetrate dense vegetation and remain effective regardless of weather conditions.