An animal detection system with the warning lights activated
resulted in 1.52 mi/h lower vehicle speeds (compared to warning
lights off) for passenger cars and pick-ups. Alerting drivers to
the presence of large animals in the road at Yellowstone
National Park. The study area was on US Highway 191 inside of
the Yellowstone National Park, with a posted speed limit of 55
mi/hour. The data collection period occurred over two weeks in
which there was mostly no precipitation. Researchers installed
three traffic counters and road tubes outside and inside of the
detection area. The counters recorded the date, time, vehicle
type, vehicle speed and gap (in seconds) between vehicles. When
vehicles moved in platoons, only the speed of the first vehicle
in a platoon was used as a data point when the signs were
activated (since the following vehicles may be influenced by the
speed of the first one). A sample size of 2,428 vehicles per 24
hour period was used. The deployment of an animal detection
system at Yellowstone Nat