This is my first hive, started in the spring, in Dallas urban area. It is an 8 frame size and now has (I think) 3 full brood supers. (I haven't checked the lower two, though.) I have been feeding with a top feeder a couple of months. Recently, the activity around the hive entrance has been really intense with ?100's of bees going in and out per minute and visable pollen on returning bees. I went out of town for about 5 days and returned to find that the activity is markedly reduced, maybe 20 bees per minute at best during daytime. We have had a bit of a change in weather with a temp drop into the 50's, from the 70's. I removed the top feeder which had run dry and they were making comb all over it. (they normally empty 2 gal of 1:1 sugar water in 4 days). I noted that the top super appeared 'filled up' with capped honey cells visable and 'normal' activity although I did not remove any of the foundation boards. Looking from the bottom through the screen, there are some bees moving around slowly, but hard to say if normal. I completely removed the feeder to clean it out and just replaced it with the top board. I have a couple of questions. My first concern was that someone poisoned my bees. I had started a prior hive in a rural area and I am pretty sure that is what happened as it was full of dead bees and moths at one point and there were some issues with neighbors, so I am a bit paranoid after that incident. It is really not so cold, now in the 60's, but we have had a bout of rain x 2 days and still activity is slow. What I am wondering is this - Does bee activity suddenly drop at some point at a certain temp or time of year? Does it return if we get a brief warm spell? I suspect that I should take off each brood super and inspect and look for the queen as well but I haven't had the time to disassemble the whole thing. Another question - since all supers are (presumably) full, should I add yet another super at this time in the year? If I do, I have a queen excluder grid - should I put it under the new super? And last question - should I continue to top feed over the winter if everything is full at this point? Thanks for reading. I know these are basic questions, but I want to start strong in the spring and make some honey!