re: wait... how can this be duck hunter numbers declining......

Just because duck hunter numbers are decreasing doesn't mean that popular hunting areas are becoming less pressured. The advent of social media I think leads to heavily congested public opportunities. And where you used to have a lot of people hunting private land, since the general population has shifted more urban, less people own hunting land and more groups of upper-class individuals are monopolizing the good private land hunting.

ETA: On the flip side, record duck numbers don't mean that everyone is killing a ton of ducks either. If you have large tracts of unhuntable or lightly hunted land that holds tons of birds, you won't see or kill them on the accessible public land. Also, duck migration patterns have shifted. The central flyway is holding a higher percentage than it did historically and on a micro-scale, heavily pressured areas year after year will push birds out to adjacent land if it provides similar rest and feeding opportunities with far less pressure.