Deer mating season in October and November is bringing a higher than usual threat of car-deer crashes.State transportation department officials have issued a warning regarding the threat of car-deer crashes. Law enforcement agencies reported about 18,900 crashes last year. The highest number happened in Dane and Shawano counties. David Pabst of the Wisconsin DOT says drivers should slow down whenever they see deer. He says if a collision appears to be unavoidable, it's safe to hit the brakes and hit the deer rather than swerve to try and miss it.