DEER CROSSING SIGNING GENERAL March 2018
Deer crashes have been one of the highest crash types on county highways in recent years.
There are a number of factors which may influence deer crash rate, including herd
population, herd migration, herd location, roadside vegetation management, roadway
factors (speed limits, lighting, etc.), driver education, use of deer crossing deterrent
devices (reflectors, scent boxes, vehicle whistles, wildlife underpasses, etc.), active
warning devices such as motion detectors/warning light or static warning signs.
Traditionally, static warning signs have been installed in areas with higher deer-vehicle
crashes (DVCs). There has been much debate over the usage of static deer crossings signs
and their effectiveness. Many transportation professionals recognize the fact that
warning signs are most effective (result in alteration of speed and/or path choice) when
there is an obvious danger ahead (examples: curve or turn). The use of warning signs
that alert drivers to sporadic or general possibilities (examples: deer crossing and slow
children) have been shown to not have a consistent impact on driver behavior. The
widespread use or sign proliferation also reduces the effectiveness of the sign and leads
to drivers disregarding the signs. Several states and agencies have performed studies to
assess the effectiveness of static deer crossing warning signs. The studies have
concluded that the usage of static deer crossing warning signs do not generally reduce
vehicle speeds (one measure of warning sign effectiveness). As a result, the studies
have yielded no reduction in DVCs.
Static sign studies have been performed by the following agencies:
1. Assessing the Effectiveness of Deer Warning Signs. Published by Kansas Department
of Transportation and University of Kansas at Lawrence, April 2006.
2. Wildlife – Vehicle Collision and Crossing Mitigation Measures: A Toolbox for the
Montana Department of Transportation. Published by Montana Department of
Transportation and Montana State University, May 2007.
3. An Ecological Landscape Study of Deer-Vehicle Collisions in Kent County, Michigan.
Published by Kent County Road Commission and White Water Associates, Inc., January
4. Deer Crossing Signs and Technologies. Published by Deer-Vehicle Crash Information
Clearinghouse (DVCIC), Maintained by Texas Transportation Institute,
5. Deer Avoidance: The assessment of real world enhanced deer signage in a virtual
environment. Published by Minnesota Department of Transportation,
Several dynamic types of deer crossing signs are currently being explored as potential
countermeasures and are discussed in the studies listed above. These types of signs have
been designed to activate when deer are detected near the roadway. Studies are taking
place in Indiana, Minnesota, Montana, Pennsylvania, Utah, and Washington. The
development of methods to control car/deer collisions is continuing to evolve, and over
time policies such as this will be subject to change. At present, due to funding
limitations, Fond du Lac County is not utilizing dynamic deer crossing warning sign
systems. Fond du Lac County will consider issuing a permit to an entity to pursue the
usage of dynamic deer crossing signs.
One effective countermeasure pointed out in the Kansas study is the usage of public
awareness techniques to educate the motoring public regarding the seasonal and time of
day characteristics of deer-vehicle crashes. This could be accomplished effectively
through the different types of media outlets.
Based upon the findings of the various studies mentioned above, Fond du Lac County will
implement the following policy for usage of static deer crossing warning signs:
1. No new static deer crossing warning signs will be installed on county highways.
2. Static deer crossing signs that are currently in place will be allowed to remain
until the end of their useful life or when opportunities for removal are available.
These opportunities would include sign knockdowns and improvement projects.
Click here for a PDF version of this document