Ensure public familiarity with animal detection systems by displaying signs so that they are easily understood and by providing basic system information prior to deployment.
Montana and Pennsylvania’s experience with deploying animal detection systems.
Made Public Date


United States


Yellowstone National Park
United States

Animal Vehicle Crash Mitigation Using Advanced Technology Phase I: Review, Design and Implementation


Animal-vehicle collisions affect human safety, property and wildlife. The number of these types of collisions has increased substantially over the last few decades. This report describes the results of a project that explored the prospects for a relatively new mitigation measure to reduce animal-vehicle collisions: animal detection systems. Animal detection systems use ITS to detect large animals when they approach the road and to warn oncoming vehicles of their presence.

The report identifies existing animal detection system technologies and describes the selection of two experimental detection systems and their installation at two field sites:

  • US Highway 191, in Yellowstone National Park, Montana. This site stood out because of its national visibility, representative terrain and vegetation (forested hills and mountains), the abundance of large mammals, and its proximity to the office of the Western Transportation Institute at Montana State University.
  • Highway 22/322, near Thompsontown (northwest of Harrisburg) Pennsylvania (PA). This site ranked high because of the large number of animal-vehicle collisions; controlled access; limited fluctuations of deer populations; relative proximity to the vendor; and the terrain, vegetation and large animals seemed representative for eastern states.

This report documents experiences and lessons learned with planning and design, installation, operation and maintenance, test results on reliability, and user acceptance of animal detection systems.

Lessons Learned

Animal detection systems are relatively new on the traveler information scene and as a result many people have not become accustomed to seeing them on roadsides. It takes time before drivers become familiar with their presence and are able to interpret their message as quickly as they would more common road signs. It is in the best interest of agencies deploying animal detection systems to take every measure possible to develop a certain level of public familiarity.

To increase the public’s familiarity with animal detection systems informational campaigns should be conducted prior to deployment. For people to become familiar with animal detection systems on a wider scale, agencies should coordinate with one another to develop display standards. Last, so drivers stay cautious and alert when message boards are blank, continual caution messages should be displayed at points where the potential for animal crossings is frequent.

  • Inform local media outlets prior to and during initial system deployment. The media are concerned with the number of and increase in animal-vehicle collisions for various reasons: human safety, animal welfare, habitat connectivity, and population viability, especially for large mammal species. Since animal detection systems are located along roads, they are highly visible to the public, including journalists. It is recommended to send out a press release and a project fact sheet just before the installation of an animal detection system and prepare for questions from the media. However, if the animal detection system does not become operational shortly after it has been installed, negative articles may start to appear in the media; if so, appropriate responses should also be prepared for media inquiries resulting from this situation.
  • Develop Standards for displaying warning signs and signals. As more animal detection systems are installed and become operational, the need for standardization of warning signs and signals becomes more important. However, there remains much to be learned about how different signs may contribute to the effectiveness of an animal detection system, and regulations for traffic signs sometimes differ between states.
    • In Montana, graphic warning signs with a black silhouette of an elk or a moose on a yellow background have been stolen in the past. This may be a reason to use text messages only, e.g., "wildlife crossing" on a yellow background. Furthermore, some states may need to modify the regulations regarding ITS signage to allow for signs that stimulate the drivers to use “extra” caution when the warning signs and signals are activated.
  • Display cautionary messages even in the perceived absence of large animals. It should never be assumed that animal detection systems detect all large animals that approach the road. False negatives should be kept to an absolute minimum, but depending on the terrain, weather conditions, location of the sensors, potential equipment failure and weather conditions, the system may have blind spots or may be faced with very challenging conditions at certain times. Therefore the warning signs should inform drivers that they should pay “extra attention” to the potential presence of large animals on or near the road when the flashing warning lights are activated, rather than suggest that there are no large animals present (when the warning lights are not activated).

As the number of deployed animal detection systems increases, the driving public will become more familiar with their presence and the information they provide. Nonetheless, information displayed on message boards needs to be easily understood and pertinent to actual conditions. The way in which information is displayed should differ as little as possible between sites so that the general populace as a whole familiarizes with animal detection systems at the nation scale. Even as animal detection systems become more common, the need for outreach campaigns exists in areas experiencing their first deployment. This guidance helps to address the ITS goal of safety.

Goal Areas