I commute through rural Michigan, going on 3 years now.

If you're bored, it can be a hobby to watch a newly-dead deer decompose down to skeleton over the course of a year or so.

The skunk that got whacked back in December on mile 6 of my commute finally stopped making skunk smell, now it's just rotting which I'm used to.

There are some interesting smells as the snow melts, but usually the carcasses have dehydrated a bit by then and it's not overpowering.

A deer that's about 3 weeks dead is the worst. Hasn't dried out yet, and the stench can be pretty bad out to 100 feet or so.

I rarely see anyone take care of roadkill. If some happens in front of my property I'll go out with a shovel and bury it, otherwise I'll be watching it for months.