More efficient farming machines/practices, Earlier maturing rice and beans, the 0 grade field. On and on in the ag world. Results in less grain left in the fields, what's left re sprouts typically, and fields are worked for next year right after harvest.
Relentless pressure
Weather not cooperating
Rest areas / flooded corn / banking ducks / white oak style operations
Spinning wing decoys slaughtering yearling ducks up north
More traveling hunters
Better hunter technology (guns/ammo/clothing/etc)
Boats / mud boats and machines that go anywhere
Skybusting and general bad practices conditioning ducks
It's a lot of different things hurting Arkansas