Road covered in dead snakesThousands of snakes were killed when crossing the highway. Photo Courtesy of Canadian Amphibian and Reptile Conservation NetworkEach year when the red-sided garter snakes return to their dens, many end up crossing a two-mile section of Manitoba Provincial Trunk Highway No. 17. Crossing the highway has always been a dangerous task for these little snakes, as most are not able to move fast enough to avoid the rushing cars. However, within the last 15 to 20 years, it was noticed that more snakes were being killed on the highway. At times, the highway would become completely covered with the bodies of snakes run over by oncoming cars. It was estimated that upward of 25,000 – 35, 000 snakes were being killed each fall on this small section of the highway. The local people and the Manitoba Department of Conservation made the decision to step in and do something to help save the lives of these snakes and to help protect their population.

Sign warning drivers of snakes crossingA sign on the highway reminds motorists to watch for snakes on the road. Photo Courtesy of Canadian Amphibian and Reptile Conservation Network A committee was formed to look at the issue and a University of Manitoba student researched possible solutions for his thesis. After looking at the many ideas presented, it was decided that the best way to save the lives of these snakes would be to install tunnels underneath the highway which would take the snakes safely from one side to the other. There were a few problems with this solution, one of them being the cost of such an endeavor. It was estimated that this project would cost between $250 to $300 thousand dollars. Luckily, a few employees from Manitoba Hydro, an electric energy and natural gas company, had heard about the situation and had an idea that could help. These employees came to the committee and suggested that their horizontal-boring equipment would be quite useful in quickly and efficiently boring the holes for the tunnels underneath the highway, at very little cost. Between 2001 and 2003, Manitoba Hydro donated equipment and manpower to create 12 tunnels underneath the highway.

Tunnel build under the road for snakes to slither throughSnake tunnel under the highway. Photo Courtesy of Canadian Amphibian and Reptile Conservation Network Snakes exhibit natural wall-following behavior, so it was decided that this behavior could be used to make sure that the snakes would enter the tunnels rather than continuing to slither over the road. Low, galvanized-hardware fences were installed which would “funnel” the snakes to the tunnel so that they would naturally go directly underneath the highway. Although some snakes found ways to get around or over the fence, and some are still killed, the total cost of $100,000 for the tunnels has helped to reduce the number of snakes killed each year by approximately 75 percent. This reduction will help to ensure that these snakes will continue to congregate at the Narcisse Snake Dens for many years to come.