The other day, a swarm of angry, hungry honeybees from a neighbor's hives came over and began fighting with our bees, trying to get into our hives. We realized this was happening after they had already been there awhile, as we could see a pile of dead bees in front of our hives as well as the unusual activity of the angry swarm. The bees were coming directly to our hives from the neighbor's property behind our house, where they also have two beehives.
I followed the robbing bees to see for sure where they were going, and sure enough, they headed straight back to his hives. His bees are darker in color and more aggressive than ours. He has told me that he has Italian honeybees, but that is what we have, and his bees look more like Carniolans. I watched his bees go back and forth from our hives to his for several days.
To try to save our bees, we adjusted the entrance reducer to the smallest opening. We also duct taped along the lids and middle of the hives to make sure no bees could enter through any crevice along the edge.
Moving the hive wasn't an option because they would find it again, unless it was moved more than 3 miles away. We didn't have another space for them that far away.
Our efforts didn't prevent our bee colonies from collapsing. Tonight I pulled the hives apart and examined everything. All the honey that our bees had stored up is gone and there are no more bees. There is no brood left. It's all gone. Just empty comb where brood and honey used to be. We are so sad, heartbroken, to see this happen.
As new beekeepers, we had prepared for all the other possibilities, completing varroa mite treatments on the recommended schedule, purchasing nosema treatments in case they were needed, providing sugar water and pollen patties from spring to early summer, completing hive inspections on a recommended schedule, attending beekeeper association trainings, registering our hives with the state, and so on. I still have 25 pounds of sugar in the kitchen for this fall. We never once considered that another person's honeybee hives would be the downfall. Honeybees killing honeybees! I just can't believe it. In the classes on beekeeping that we took, the issue of robbing was barely touched on and when it did come up, it was about other types of bees (wasps, hornets, bumblebees, etc.) robbing the hive.
How do we prevent this from happening again next year? I'm not sure, because I truly believe that a good part of what happened has to do with the way our neighbor is managing his hives. He told us that he lost thousands of bees in late spring because he didn't feed them, and so he refilled his hives with thousands more bees. I think he overfilled his hives with bees. They were hungry because there wasn't enough flowering in the area to support that many bees after the recent heat wave. He planted no flowers in his yard to help feed his bees. The only solution I can think of is to put out a sugar water feeder in the yard somewhere as a decoy to keep his bees happy so that they don't come over here, but knowing how quickly those feeders were depleted in my own hives over the spring, such a solution in the future would be very expensive. Perhaps I can ask about this problem at our next beekeepers' association meeting; other beekeepers there may have some suggestions.