I wouldn't go that far. Wild birds on private land are still wild birds. They are wary of predators and hunters just like they are on public land based solely on natural instinct to survive. I would definitely say that after the first week of the season, birds on public land are generally more difficult to harvest though.
It's all a matter of pressure. Regardless of which land they live on, the more pressure they see, the "smarter" they become. It's FINDING them, at the right time, that becomes the biggest challenge. They use pressured habitat more & more sparingly, and at very specific times, as the season rolls on. And generally, public land gets exponentially more pressure than most private land.
I hunted private land 3 times last year (all somewhat pressured birds), & 2 of those times, birds did things they'd never, EVER do on the public areas I hunt. Hunting a cattail draw about 3/8-mile long. Birds begin to flush up ahead, but several flew down the draw a couple/few hundred yards & landed again. Hunting a small cattail slough, birds flushing up ahead & flying who knows where to safety. A half hour later, they began to come back. I'd never see either of those things on the public places I hunt. (maybe, MAYBE during the first week of the season)
