I was able to find some ranch property near water with birds by knocking on doors/phone calls, especially for archery. Took my first Merriam's in 2014 that way, (the rancher had died when I returned last year); then got 2 near the end of the archery season up on The Ridge near an area with lots of birds.
I do a lot of driving around scouting the public land and yes they are in bigger flocks and mostly on private but move a lot. The flocks will start to break especially if the weather is nice, then regroup as it gets nasty, cold and snowy again... from what I have seen. Pattern the birds and move in, DSD jake and hen set up as intruders along with calling help bring the birds to you. Last year I found them in two spots and got one at each, was 22F both mornings to start.