Updated: Mar 5, 2019
balancing the travel needs of people and wildlife
We’ve grown accustomed to the sight: a dead deer, badger or bird on the side of the road. For many of us a brief moment of sadness and reflection, gone within seconds as we focus again on the road ahead and getting ourselves where we need to go, safely. With highway networks expanding and traffic increasing, it seems we have largely accepted wildlife-vehicle collisions as a sad but unavoidable consequence of our ever-increasing human presence. Unfortunately, the truth of wildlife-vehicle collisions is that they aren’t just a sad sight we see every once in a while but, added up, a huge loss of animal lives that occurs every single day on our roads. There is also the unseen loss: infrastructure systems break up wildlife habitats into smaller and smaller pieces, and this fragmentation is one of the main reasons for the decline of biodiversity. This tragic issue receives little attention considering the economic cost alone, not to mention the suffering and loss of life, human and animal alike. But there is hope: throughout the world, reducing the impact of infrastructure is posing challenges but also sparking creativity, and we continue to find ways to balance the safety of wildlife with the travel needs of people. Over- and underpasses for animals help mitigate the impacts of habitat fragmentation and reduce casualties.
According to an excerpt from Mia Rishel’s paper Considerations when designing large mammal crossing structures and the importance of exclusion fencing, approximately 200 people die every year in the U.S. alone and of course countless animals. Wildlife-vehicle collisions amount to a huge infrastructure problem: at least 1.5 million deer-vehicle collisions — that is, not counting collisions involving other types of wildlife — occurred between the summers of 2011 and 2012; they claimed 200 human lives and cost an estimated total of $4 billion in damage to vehicles alone. The U.S. Department of Transportation reported that between 1990 and 2004, the number of vehicle collisions in general remained fairly stable, but the number of wildlife collisions increased by fifty percent to make up a total of five percent of all reported collisions. This disproportionate growth is believed to have been caused by an increase in both vehicles on the road (and miles traveled) and an increase in deer numbers throughout the country. As the number of people and vehicles on our roads increases, so will wildlife collisions. It’s time to acknowledge the scope of the problem and take measures to solve it. The annual cost for wildlife-vehicle collisions in the U.S. is $8 billion. That’s enough to construct several hundred crossings each year and practically erase this problem within the next few decades. We now have the research to help us design crossings effectively to get people and wildlife where they need to go safely. Wildlife crossings let us enjoy our scenic bywaysbeautiful highways knowing animals are passing safely above or below us. We need to join forces with scientists, wildlife advocates, politicians and stakeholders to design and implement crossings that are constructed in smart and sustainable ways and built where they are most needed to reduce collisions and increase habitat connectivity. TransArc hopes to be part of a movement to help balance the travel needs of people and wildlife, and create smart, esthetic structures that stand the test of time.
You can find the link to Mia's academic paper here.
Considerations when designing large mammal crossing structures, and the importance of exclusion fencing