that's all I go after... I'm at the point where I could care less about killing anything less than the biggest bird on the farm, although I haven't lost a bit of the fire hunting them.
the only way I've been able to kill the boss this time of the year (because they ALWAYS have hens) is to spot them on the ground, and only if they are in the woods or at the very edge of the fields (I don't even bother if they are in the middle of the fields), sneak to within 50-75 yards of them, and just lightly scratch leaves and purr. They'll keep checking each of their hens for receptiveness, and eventually think you are one of his current harem and will drift over to you to check you out as well. But you have to get CLOSE for it to work... and that's a feat in itself with all the hen's eyes.
I have had 3 or 4 occasions where just by blind luck the boss got separated from his harem during the evening and I set up on him in between him and his girls in the dark. If that happens, it's a slam dunk, hunt over by 6:15 every time. But that scenario in unbelievably rare for them to be separated, and you just getting lucky enough to post up between the two groups in the dark.
Once in a blue moon the lead hen in the harem will come straight to your calls pissed off and lead the whole group in... had that work maybe 2% of my setups on the boss and his girls.