October 15th, 2018
Here in Windsor, Ontario the weather is finally starting to chill out. This means that we, the Ojibway Prairie Massasauga team, have wrapped up certain field projects (like occupancy and gestation site surveys) and are focusing on others (like road mortality and barrier fence surveys). Goodbye warm and sunny walks through the woods looking for snakes and hello cool fall bike rides.
Road mortality and habitat fragmentation due to roads threaten reptile populations throughout Ontario. To monitor the impacts of road mortality on local snake populations and to test the effectiveness of snake barrier fencing that we have installed, we conduct road mortality surveys by bike every other day. During these surveys we travel the main roads of the Ojibway Prairie Complex and Greater Park Ecosystem and record all dead vertebrates observed. These surveys are conducted from May to October, but in the Fall snakes are on the move to hibernacula (overwintering sites). This annual movement, coupled with an increase of young-of-the-year snakes, is associated with a spike in road mortality observations.
Early October is an especially bad time for seeing dead snakes on our study roads. Very quickly we go from seeing fewer than five snakes a survey to over 20 dead snakes in a day! During the last four surveys alone, we recorded 169 dead vertebrates, 116 of those being snakes. Most were common species such as Eastern Gartersnakes and Northern Brownsnakes, however, one quarter were Species at Risk (Butler’s Gartersnakes and Eastern Foxsnakes; Figure 2). Over the years we have found five other SAR dead on roads: Blanding’s Turtle, Eastern Massasauga, Eastern Musk Turtle, Northern Map Turtle, and Snapping Turtle. Thankfully only one Eastern Massasauga was observed dead-on-road in nine years of study.
We see very few live animals during road mortality surveys, but on the rare occasion we are fortunate to move a live snake off the road. When this happens we feel like heroes, saving the world one small snake at a time. Kaitlyn Hall, our Field Technician, had one of those moments while doing a road mortality survey the other night. She was able to intercept an adult Northern Brownsnake alive on the road and after processing it was able to send it on its way.
Catching random snakes crossing the road is not the only way we try to mitigate the threat of road mortality. We also installed snake barrier fences to reduce the number of snakes that end up dead on the road. These snake fences are installed seasonally at road kill “hot spots” that have been identified from previously collected data. Our road mortality surveys are then used to assess the effectiveness of the snake fences. Check out our Working out at Work video to see how we install the snake fence.
So, what can the average person do to reduce the number of snakes and other creatures killed on roads? Well, if you happen to live in Windsor or LaSalle, pay attention to the Wildlife Crossing signs installed in and around the Ojibway Prairie Complex (Figure 3). Slow down while driving in these areas, look out for snakes and turtles on the road, and, if you see one and if it’s safe to do so, help the animal cross the road. Even better, though, is to avoid driving through the Ojibway Prairie Complex altogether! Matchette and Malden roads have high reptile mortality and can be easily avoided by using the Herb-Gray Parkway or the Ojibway Parkway. The less we all drive our cars through the Ojibway Prairie Complex, the lower the negative impact we will collectively have on this endangered ecosystem and the creatures that depend on it for survival.
Jennifer Barden – Lead Field Technician – Ojibway Prairie Reptile Recovery