Animal-activated highway crosswalk: long-term impact on elk-vehicle collisions, vehicle speeds, and motorist braking response

Abstract

After reconstruction of a highway section with three wildlife underpasses, but only limited wildlife exclusion fencing, elk (Cervus canadensis)-vehicle collisions (EVC) increased 21%. We retrofitted an existing 1-m right-of-way fence along 4.2 km, raising it to 2.2 −2.4 m in height and tying it into underpasses at the project's east end. With no logical western fence terminus, we installed an animalactivated detection system (AADS) and motorist alert signage at a designated at-grade crosswalk to prevent collisions when animals crossed. Our goal was to achieve modified motorist behavior without long-term habituation while allowing wildlife to cross via the crosswalk, promoting highway safety and landscape connectivity. Beforeproject EVC (9.33/year) declined 97% after the new fencing. Our AADS achieved reduced vehicle speeds (13%) and increased motorist alertness (5.5-fold increase) with signs activated. Average speed reduction and braking response remained significantly higher with sign activation across all 9 years of our evaluation. Thus, our placeand time-specific AADS design successfully modified motorist behavior without habituation.

Green Infrastructure Design for Transport Projects:

“…Wildlife warning signage with flashing lights and variable message boards have the potential to be more effective than static warning signs (Pojar et al 1975, Sullivan et al 2004, Gagnon et al 2018, Huijser et al 2015a. However, signs with flashing lights may elicit motorist habituation if they operate continuously (Lehnert and Bissonette 1997).…”

“…However, continuously operating signage typically results in motorist habituation (Lehnert and Bissonette 1997) that ultimately limits effectiveness of the crosswalk in preventing WvC (Huijser et al 2015a). yet at-grade crossings integrated with animal-activated detection systems (Huijser et al 2015) intended to modify driver behavior, using time-specific flashing signs to warn when animals are adjacent to a roadway, have the potential to avoid motorist habituation (Huijser et al 2015a), as accomplished by Gagnon et al (2018) over a 9-year period in the uS. These technologies are potentially quite expensive and require regular monitoring and maintenance to ensure effectiveness and reliability of operation, which are critical to their success.…”

“…intended to alert motorists to the potential for crossing animals, is warranted. Gagnon et al (2018) successfully employed an animal-activated detection system at a fence terminus that triggered flashing and message signs when animals were present, with only a single deer-vehicle collision at a designated "crosswalk" where over 2,000 deer and elk crossed over 9 years, and without measurable motorist habituation (where motorists ignore signage over time) to alert signage.…”

Developing a correction factor to apply to animal–vehicle collision data for improved road mitigation measures

“…AVC records are often used to locate optimal sites for these measures. For example, AVC data have been used solely, or in conjunction with, wildlife movement data to plan the location of mitigation measures on roads (Lenhert and Bissonette 1998;Van Manen et al 2012;Gagnon et al 2019). AVC data are also analysed together with landscape and road variables to identify where high AVC rates might occur, so as to help inform the underlying mechanisms leading to future AVCs (Ramp et al 2005;Litvaitis and Tash 2008;Ward et al 2011;Clevenger et al 2015).…”

A New Roadway Eventual Obstacle Detection System Based on Computer Vision

“…Huijser et al [ 11 ] and Huijser et al [ 12 ] described, analysed and compared different RADS installed in USA and Europe. Huijser et al [ 13 ], Grace et al [ 14 ], Grace et al [ 15 ] and Gagnon et al [ 16 ], studied the effect of RADS over the driver’s behaviour, concluding that the effect of installing RADS is very positive. However, all authors agree that the accuracy of RADS should be improved.…”