Roadside wildlife detection systems use radar and lasers to save wild animals and protect drivers who might cross their paths.
Hitting an unexpected moose with a car can be a fatal encounter. In 2009, the Ontario Ministry of Transportation (MTO) in Canada began installing wildlife sensor and alert systems to reduce the number of animal-vehicle collisions on its highways. The move was more than just a safety measure; these crashes are costly. Collisions with wild animals, which account for about six percent of all collisions in Ontario, cost the province more than $100 million annually in health care, vehicle repair and emergency services costs.
The MTO has installed two types of systems – one uses laser tripwires to detect animals and the other uses radar, an alternative that was found to address some of the challenges posed by laser systems. Neither system has yet been determined to be superior to the other. The ministry will continue testing to determine which method works better. Officials report, however, that both systems slow down traffic, and initial results point to fewer collisions overall.
Similar systems are also being tested around the U.S.
Tripwire systems were installed on Ontario's Highway 17 in 2009 and on Highway 6 in 2012, in areas where wildlife are often encountered on roadways. If the system is triggered, yellow lights flash to alert motorists that wildlife is within approximately one mile of the sensor. In the five years before the first system was installed, that area saw 11 collisions, but in the four years since, only one collision has been reported.
Powered by solar panels and backup batteries, the two tripwire installations cost the province about $766,000 (U.S.). The MTO will continue evaluating the effectiveness of the systems, according to MTO spokesperson Bob Nichols.
Despite the reduction in collisions, project leaders also reported some challenges with the technology. The tripwires can be easily triggered by false alarms, including small animals, rain, or vegetation. While the sensors can be adjusted, operators found it impossible to eliminate false triggers while making sure that large animals are still detected.
Also, because system lights flash for just three minutes upon detection of an animal, any animal that stays still for more than three minutes can go undetected and the lights will not flash. The three-minute alert period can also be triggered by an animal that quickly runs across the highway, and although the animal could be gone, the system would still alert drivers.
In March 2012, the MTO installed a new system, called the Large Animal Warning and Detection System (LAWDS) on Highway 416 that uses radar, instead of lasers, to detect large animals. In early 2013, a second radar system was installed on Highway 138. The system backend provides operators with a map of the road, indicating where the animal was detected. The map is updated once per second. In addition to addressing many of the problems caused by laser tripwires, the system also provides operators with information about traffic, such as speed and volume, or even whether a vehicle is a car or truck.
Initial results from the radar system show that traffic speed is reduced by 15 percent when the system is active.
For both systems, the MTO partnered with the Ontario Provincial Police and though no definite conclusions have been reported by the MTO, police believe the systems are making a difference, Nichols said.
In Florida, it’s the panther, not the moose, that led researchers to install (PDF) the Roadside Animal Detection System (RADS) on a small section of Highway 41. The Florida Department of Transportation installed the solar-powered sensor system in January 2012 and will continue monitoring the system for two years using a $450,000 grant.
While safety was also cited as motivation for RADS, the system was also put in place to help protect the Florida panther, an endangered species whose total population in the U.S. is estimated at as low as 100. The mammal had its numbers reduced in 2010 when three collisions in a three-day period killed three panthers. RADS is also intended to protect Florida's black bear and white-tailed deer populations.
In 2011, the Colorado Department of Transportation installed a wildlife detection system that uses sensors buried nine inches underground alongside a stretch of Highway 160. If the sensors are triggered by footsteps, signs alongside the roads light up. This system was chosen, officials said, because it avoids the false alarms caused by laser systems and minimizes environmental impact.