We took yesterday off -- 45 mph winds and falling trees will keep me out of the timber (and without a chain saw, off the back roads). As for the skittishness of grouse, I'm sure there is something to the idea that grouse can learn from past experience. Gary, I also believe that thinning cover can make grouse more wary, but, like you mention, if they have some security of cover, like blowdowns or grapevine tangles, they will often hold tighter, even later in the year. As far as beepers go, it certainly seems plausible that birds can learn to associate that sound with danger, but I know enough science to not let
my empirical observations set a rule for all.
I run my dogs with beepers in the Northwoods to keep a closer watch on them and, like wearing a bell in bear country, to let the wolves know we're in the area (and hopefully, for them to leave it!). We had a wolf come after one of our dogs in a clearcut some years back, and I've been spooked by that encounter ever since. I actually shot at the wolf to stop its advance. A 28 gauge load of 8s through an open choke and the very large wolf did not even slow or blink (this was at about 45 yards). I thought I was up for a close range shot when it just stopped, gave us a dirty look, and casually strolled off. My 70 pound Gordon would have been carried off by that very, very large wolf. I've read all the reports on wolves and dogs in the north country, and I know there is low risk for bird dogs, but when you have a close encounter, you sometimes have a hard time letting that experience go. There's that empirical knowledge thing again.
I'll still say that later in the season, there are a host of circumstances that cause grouse to be more skittish -- hunting pressure, thinning cover, beepers(?), etc. I know that Burton Spiller wrote that birds became more skittish during low periods of the cycle. I guess the idea is that many of the birds encountered then were not birds of the year and had more experience with hunters. Who know?! I do know that they are skittish now, and that the fact that they are is what hunting them is about, and I'm not about to let some skittish birds keep me from enjoying myself...or my dogs to not love what they are doing.
I hope everyone else's birds are not so skittish, and that you all shoot better than I do.
(I'm pretty sure you do anyway.) And, I hope you get as much enjoyment out of the hunt.