In 2006 between 4 other people and I who hunted regularly together, we harvested 177 roosters that season. This was an hour from the metro in central Minnesota.
After that season, I never thought we'd see or shoot that many birds again. In 2007, we got 207. I can recall seeing well over 100 birds in one spot many times of the course of those two seasons.
All of these birds were taken off private land and my Grandfather shot probably half of them because he had just retired as an insurance agent in a small town and he had permission to hunt in the entire county it seemed like. I can recall hunting with him and my uncle on both of those openers and finishing in less than half an hour on opening day at the first spot. This was before they extended the season all the way through December and raised the bag limit to 3 starting Dec 1, mind you.
Nowadays I primarily hunt solo or with one other person and I'm a long ways from being retired, so its never going to be as good as that because I simply can't hunt as much. Much of the habitat still looks the same as it did back in the mid 2000's though in this area. Big Ag has not taken it over.