Some states, Utah comes to mind, have put in extensive deer fencing and over/under pass animal crossings in high mortality areas. WA did this for sheep on the 97A.
I'd like to see the rate Utah was at before the fences. Driving some of those highways there's a dead deer every hundred yards, then you come to a section with fence and there's nothing laying on the side of the road.
I bet if they did a breakdown for WA most all the deer strikes are in eastern WA and likely most in Okanogan County. Lord knows my car is pretty banged up... most running right into the sides...