Contractors are rolling out eight miles of fencing along U.S. Highway 97 near Lava Butte, the final step in a multiyear effort to protect deer migration routes and minimize collisions between motorists and wildlife.

A small portion of the money the Oregon Department of Transportation has spent to expand the highway south of Bend has been dedicated to deer-related efforts, including the fencing, two migratory passages beneath the roadway and pads that will deliver an electric shock to a deer’s feet should it try to wander up an offramp and into traffic.

Spokesman Peter Murphy said ODOT has previously built passages for frogs and other small amphibians, but the Lava Butte project is the agency’s first attempt to provide crossings for large wildlife beneath a highway.

Deer making the seasonal migration between the Cascades and the area near Fort Rock must cross the highway, and a gap in the Newberry Crater lava flow guides many of them toward Lava Butte, said Sandra Jacobson, a wildlife biologist with the Forest Service who consulted with ODOT on the project. Though many do cross the highway near Lava Butte, Jacobson said many others are apparently intimidated by the traffic and will travel parallel to the highway south of La Pine to make the crossing.

Soon, deer approaching the area from either side of the highway will encounter four miles of fence. As the deer move along the fence in search of an opening, they’ll find two underpasses — one at Lava Lands, where a passage has been built alongside the access road to the visitors center, and one deer-dedicated underpass about a mile south of Cottonwood Road, the northern entrance to Sunriver.

Murphy said ODOT would not have built the deer passages had it not already been planning to rebuild the highway, and if not for studies identifying the area as a hot spot for collisions between vehicles and animals. Between 2004 and 2006, ODOT recorded 42 instances in which vehicles struck and killed deer. No one knows how many deer may have been hit and merely injured by vehicles over this period.

Jacobson said deer have such a strong biological drive to migrate that they will typically take the first opportunity they have to cross an obstacle safely, though they’re still somewhat wary of underpasses. One study of an unfenced highway outfitted with underpasses showed that elk preferred to cross above ground, she said, but the animals readily switched to the underpasses when fences went up.

The underpasses near Lava Butte have been designed to mimic the surrounding terrain in order to make deer comfortable. Thus, they feature logs, boulders and other features. The underpass at the Lava Lands visitors center is a bit of an experiment in that animals and vehicles will use the same route. However, said Jacobson, the hours of the visitors center and the animals’ preference for early morning and dusk travel should minimize conflicts.

“These will work. They will work better over time as animals find them, and the fence is key to making it work,” she said.

Although ODOT does not expect deer strikes to cease entirely in the fenced area, the crossings are expected to pay for themselves through reduced damage to vehicles.

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