From an Associated Press story in The Des Moines Register:
Testing whether deer can be scared off with real or synthetic urine from predators such as wolves, coyotes and bears was just one of several ideas that officials from eight states, including Iowa, plan to consider this week in Arden Hills, Minn., as they look for ways to reduce the number of crashes between deer and vehicles.
The eight states are pooling their money and brain power to reduce the hazard, which kills about 200 people nationwide each year. . . .
The urine would be placed in canisters set far from the road in the hope that the smell will trigger an instinct in deer to flee.
This raises a number of questions. For example, who's to say the deer will flee away from the road. And, as a reader of the above link asks, "Who's gonna hold the cup for the bears to pee in?" But more to the point: What do you think of this idea?