By Renee Seidler
Sign, sign, everywhere a sign… And these ones are meant to preserve the scenery, as opposed to the signs in Les Emmerson’s song (1970).
I know many of you have been long awaiting the fixed radar speed limit sign installations in Wilson. Where are those signs?!
We thank you for your keen interest in this joint project with Jackson Hole Wildlife Foundation, Teton County and WYDOT. All parties are excited to get these installed to help make Highway 22 in Wilson safer for our wildlife and safer for motorists. The company we contracted with to purchase the signs has been hard-hit by COVID-19 and their ability to produce the signs had been limited. However, the County recently received the signs and we expect them to be installed before the end of summer!
On a similar thread, we will also be upgrading the fixed radar signs on Highway 390. You may have noticed that we had to decommission the speed limit part of those signs. The digital speed limit message had lost its ability to synchronize with the WYDOT signs that flash lights during reduced nighttime speed limits. This led to driver confusion about the speed they should be driving. Once we install the Wilson signs, we will continue to partner with the County and WYDOT to address the signs on Highway 390 as well.
The Jackson Hole Wildlife Foundation has a long history of using multiple techniques to address wildlife-vehicle conflict on our roads (note the term: wildlife-vehicle conflict which is more encompassing than saying wildlife-vehicle collision and includes issues with landscape fragmentation and permeability, road noise impact, invasive species encroachment and much more), one of these practices is the deployment of road signs with the intent to slow drivers down and make them more aware of and attentive to their surroundings and the possibility of wildlife on the road. Jackson Hole Wildlife Foundation has built a reputation in Teton County for being the “wildlife sign organization” (but if you’re not in the loop, ask me about our good work in roadkill data collection, our contribution to the Wildlife Crossings Master Plan, our involvement in passing the SPET to provide $10 million in funding for wildlife crossings and our participation in the Wildlife Stakeholder Group for crossings in Teton County) and rightfully so. You will note that we have been very focused on funding and purchasing noticeable signs. This is not by accident of course.
One of the most important parts of a wildlife message sign is that they need to capture motorists’ attention. The classic yellow diamond-shaped wildlife sign, often with a depiction of the animal of concern like a deer, tends to have very little effect on a driver’s speed or attentiveness to the fact that wildlife are more likely to be on the road. How often do you notice the yellow diamond signs?
Signs have the greatest impact on driver behavior if they have a dynamic, novel message, are located unpredictably and have flashing lights (Hardy et al. 2006). To have a higher impact, they need to be placed selectively where the wildlife problem is. So, we write messages on our message boards that will catch a driver’s attention and will be specific to a seasonal issue (like, “young ospreys on highway, drive carefully”), then move the sign to it’s next location where its sudden appearance will catch drivers’ attention once again in a new location. Drivers’ responses to wildlife warning signs are also limited to ~500 meters before and after the sign (Al-Ghamdi and Algadhi 2004). After about a half kilometer past a sign, drivers begin to lose attention to the message. Signs that demonstrate evidence of an issue also tend to be more effective, so sometimes you will see our signs mentioning the number of animals killed to date that year at that location (Blacker and Jones 2013).
Wildlife warning signs and reduced speed limits can only have noticeable effectiveness when the speed limit of a road is already relatively low (Huijser et al. 2018, Riginos et al. 2019). This is because at higher speeds like ~55 mph or more, vehicle stopping distances are much greater and typically the distance at which a driver notices the animal is not far enough away for the vehicle to stop before colliding with the animal (Huijser et al. 2008). You will see our signs are often posted in wildlife-vehicle collision hotspots that have lower speed limits like around the junction of Highways 22 and 390 or just north of town on Highway 191. Occasionally, you will see our signs on highways at higher speed locations as well, when we have heightened concern for wildlife-vehicle collisions or we are hoping to create greater awareness around a seasonal issue, like on Teton Pass or east of Hoback on Highway 191.
Unfortunately, what motorists think they would do and what they actually do may not be congruent and, we road ecologists have a mantra: it’s so much easier to change wildlife behavior than it is to change human behavior. This has been borne out time and again in many sociological and ecological studies and begs that, when finances are not a concern, wildlife crossings are much more effective than wildlife signs at reducing wildlife-vehicle collisions and at getting animals successfully across the road, i.e., addressing landscape permeability concerns (Clevenger and Huijser 2011). But as stop-gap measures or where wildlife crossings are not feasible physically or financially, signs are often the next best thing. The best thing we can do as drivers is to pay attention to our surroundings (for instance, if you are driving next to a river or over a bridge, recognize that these are riparian zones where animals are more likely to be present and crossing the road), look ahead, scan the sides of the road, drive the speed limit or the speed indicated by conditions (slower when visibility is limited!) and remind your friends that it is au courant to be a good driver!