Reducing snake mortality

July 25, 2008

Why did the snake cross the road?

As a youngster, Adam Martinson begged his parents to let him keep snakes as pets. The researcher from the University of Calgary’s Faculty of Environmental Design is still fascinated by them, but now he handles prairie rattlesnakes and bull snakes in southeast Alberta to ensure they thrive for many years to come.

As part of his Master of Environmental Design thesis, Martinson is investigating the affects of temperature and individual physiology on how prairie rattlesnakes and bull snakes cross roads in search of food, mates and safety from predators.

“There are many reasons why snakes and roads don’t mix,” says Martinson, “For one they’re actually pretty slow moving, and because they’re venomous they typically assume defensive posture instead of fleeing a moving car.”

Martinson notes that while this behaviour was a successful strategy for millions of years, it’s one of the many reasons their numbers appear to be on the decline in Alberta.

Just what kind of decline the rattlers face is uncertain. The prairie rattler is designated as “may be at risk” by Alberta Sustainable Resource Development, and listed as “data deficient” by the Alberta Endangered Species Conservation Committee.

“As the energy industry, agriculture and other development build more roads and add to the traffic in this region snakes are going to need a helping hand if we want to keep them around,” Martinson adds, noting a recent U.S. study where similar species suffered an almost 80 percent mortality rate while trying to cross roads that service more than 2,000 cars a day.

The future need not be so bleak for Alberta’s rattlers. Martinson’s research in and around Dinosaur Provincial Park aims to uncover the relationship between temperature and movement across roads.

“We’re using controlled road crossings to develop movement models for these snakes,” says Martinson, “From our findings we hope to offer government, fish and wildlife officials and industry recommendations to help reduce mortality.”

Martinson speculates that these will range from site specific mitigations like culverts to system-based recommendations such altering traffic flow patterns to reduce snake mortality.

To those who scoff at the loss of the Alberta’s poisonous serpents, Martinson offers another view.

“While I think rattlers and other snakes should exist in their own right, there are more practical reasons that should appeal to folks who don't like snakes,” Martinson offers. “You don’t see many gophers where snake populations are high. They play an important role in keeping rodent populations down. This benefits farmers and ranchers as they play their role in the web of life.

“Ultimately, if we want healthy ecosystems in southeast Alberta, we want to keep up healthy populations of rattlers.”


To arrange an interview with Adam Martinson, contact:
Joe Obad
Senior Communications Manager
Faculty of Environmental Design
University of Calgary
jobad@ucalgary.ca
Office   (403) 220-3374
Mobile (403) 585-5826