We have been having very mild, unseasonably warm weather. This is nice for us, and I am enjoying it, but it has me a bit worried about my hives for one simple reason: robbing. I have checked and as of yesterday morning the commercial hives next to my property are still in place. I also discovered last week another location about a mile and a half as the bee flies from my hives with forty-five or so of his hives. That makes at least 75 hungry Italian commercial beehives within forage distance of my hives. There is very little left to forage on, a little dandelion here or there, a few broccoli plants gone to flower, etc., but not any great abundance of forage. With almost 70 degree temps. and sunny weather, the bees want to fly. It is a great temptation to just rob existing hives rather than try to find scare forage. I have done all I can do at this point, reducing my entrances and just waiting. The hive in the picture above now has an entrance reducer on it. The bees had already propolized the top entrances closed, so they only have to defend the bottom entrance. This have has looked pretty good so far. I rocked it and it still felt heavy. I didn't see excessive activity or fighting at the entrance. The horizontal hive had a lot of activity on the entrance, and some bees trying to get in through the inner cover holes. That worries me, but there is nothing I can do until the commercial hives disappear for the winter. When that happens, I will check all hives for honey stores. If they seem light, I will feed sugar water. I don't like to do that, but it is an extreme situation. There is no point in putting sugar water on now, robbers will just take that.
The two hives on my other property that I suspected had gone queenless did indeed die. The one favor robber bees do for me, is to make it abundantly clear if a hive is dead. But, they also take every drop of honey, so there is nothing left for me. I rocked each hive and determined they were completely empty. On a warm day when the bees from the other hives were flying, there was no activity, even from robbers, also indicating the hives were empty. I took them completely down. There was no honey, at all. They were completely and totally empty. When I got to the bottom boards, I looked for clues. Both hives had old queens - over two years old that had survived two winters each. They had both been productive queens, with good, strong hives. I had taken several successful splits off of each hive and most of what little honey I got this season came from them, so they lived a good and productive life and I don't grudge them a thing. Queens don't live forever, and their decedents do live on, just in different hive bodies. Both hives decreased activity in August, giving me indication that the queens had finally finished their course. I just waited and watched. I noticed robbing activity at the time we put winter wrap on, but wrapped anyway, in the vain hope that the hive might still be alive and that the wrap itself would cover up extra holes the robbers were using for entry. Apparently at least the one hive was dead by then anyway, because I put the entrance reducers on the same day, and when I took the hive down, I found a resident mouse that had attempted to chew its way out from the inside. It had gotten about halfway through the wooden entrance reducer, so I am confident it would not have died in there, it would have gotten out eventually. In my experience mice move in after the bees are gone, or mostly gone.
What interested me most was the bottom board debris. This gives many clues to a hive. Since I am convinced the hives died because the queens died and the bee population dwindled away, I would expect to find some varroa (weak hive = varroa moving in). I would also expect some dead bees, but not a lot because the bee population should have been small by the final demise. I would also expect that if robber bees robbed out the hive there would be some wax debris, but not a whole lot. If yellow jackets robbed out the hive, there would be a deep pile of wax debris and the frames would be chewed up. The foundationless frames would have holes chewed through the whole comb if the robbers were yellow jackets. One hive had a screened bottom board, but was on a concrete pad, so I looked through the debris below the bottom board.I found a small amount of varroa dead, at the very bottom of the piles of debris, but so few I could hardly find them. There was a small amount of wax and a relatively small number of dead bees. The other hive had a solid bottom board, so I brought it back and examined it more closely in better light. I found pretty much the same situation there. I looked very carefully to see if there were lots of dead varroa. I only found a very few. My critics will say those hives died from varroa. I will say, the queens died, the hives dwindled and robbers came in and cleaned out the hives. They were mostly honeybees because there was very little damage to the comb - only one frame I found in both hives was chewed up - and there were very few dead bees in the hive.
The bottom line is that this is a normal situation for bees in my opinion. If I wanted to say a particular hive didn't ever die, I would re-queen, or take out the old queen once a year and let them raise a new queen. I may do that with the horizontal hives because I don't like to leave them empty over a winter, but maybe that isn't so bad, I will decide at a later point on that. Both horizontal hives have new queens this year, so it won't be an issue until at least next fall. It seems that a queen may live two years at the most. She seems unlikely to go through more than two winters. It would probably be wise to replace her in the third season, but I still got a lot of brood and honey out of those hives before they died later in the season, so I don't think that would have been the best idea in this situation.