We last inspected the brood 3 weeks ago
And saw a lot less laying. I thought the cold temp has put them towards winter prep early. That said, we caught a swarm last Friday so I wouldn't rule out a drop in bee numbers as a sign of swarming. Indeed, our strongest hive has quite a lot less bees coming and going in the last few days, and my guess with them is they may have swarmed. I'm not going in to check as that would mean a Virgin queen running around. We might do one more brood check in a couple of weeks there, but not sure there is any point as we are just leaving them all alone until spring now and are sure they have heaps of winter stores.
As an aside, I am getting very confused with management practices here in WA. We have diligently checked the brood box every 2 weeks, and checkerboarded etc to manage the swarming urge. We have semi-commercial and commercial beekeeping friends who check the brood box once per year to decide if they should requeen and that is it. Is it because they have so many hives and move them to high yield areas it doesn't matter if a few swarm because they still get massive amounts?
I think next year I may try being a bit less interventional, but I don't have the guts to just do it once!