Winter is a good time for beekeepers to learn patience. At first, we feel relieved that the bees are finally settled in and don’t need any of our time. Soon, though, we start wishing for a bee fix, and start worrying about our girls. We wonder if they might be struggling with the cold, and concoct ideas to help them stay warm. This is the human in us, and we need to learn to think like a bee. I mean, learning some bee biology will help us understand what the bees are doing, and what they really need. What the bees are doing during winter is staying warm. The bees on the outside of the cluster pack their abdomens tightly together to keep the warmth inside the cluster. They can even control the level of CO2 by allowing only a certain amount of oxygen in. High CO2 levels decrease the metabolisms of the individuals. Heater bees in the center of the cluster shiver their flight muscles without moving their wings. This exercise creates heat, and the exercisers respirate a lot. They collectively breathe as much as a grown man, and put out a lot of moisture, too. This is why our bees are so good at handling the cold, but need a little help with ventilation.
During the fall, the bees propolize the seams between their hive bodies and under the inner cover, and they usually propolize any ventilation holes in the hive bodies. They do need some ventilation so that moisture doesn’t build up inside the hive, but don’t need drafts going through the cluster. I usually open the ventilation holes just a bit, using a piece of wire to make an opening about the size of a matchstick. Our flat inner covers collect condensation above the cluster, unlike the rough and rounded inside of a tree. This condensation can build up and rain back down on the bees. Wet bees are dead bees. Ventilation is the answer. Some inner covers have a notch in the rim. This notch should go toward the front of the hive in winter, so that air goes in the entrance, and is drawn back out at the top front of the hive. Placing the notch at the back of the hive would pull air from the entrance and through the cluster, not a good thing. I like to drill a ¾ inch hole in the front of the uppermost hive body, just below the finger-hold which will take care of the ventilation and also serve as an upper exit in case of wet snow on the landing board that might suffocate my bees. I drill it low like that to allow for a deeper blanket of warm air inside the hive.
Now that it is November, we really should not be moving things around in our hives. If you haven’t yet added a shim to the top so that there is room for sugar, it is possible to add one now. In most parts of the country, it will be very difficult for the bees to propolize the shim to the upper hive body now, so we will need to help them reduce drafts by duct taping the shim to the upper hive body all the way around. Do not use gorilla tape. I have had it kill my bees twice now. (Anecdotal evidence is not science, but I would prefer not to kill any more bees to prove the point).
In future years of beekeeping, plan to add the shim in October so that the bees can propolize it in place. This shim allows us to supplement our bees with dry sugar on newspaper, called the mountain camp method of bee feeding, or with bee candy that you make at home, or with fondant that is available in the baking section of most grocery stores. I have used both the mountain camp and the bee candy methods of winter feeding. It gives me a bit of peace about the early spring, and also ensures that any moisture that rises from the cluster will be absorbed by the sugar or candy. In fact, the bees cannot use dry sugar, so the condensation is required to make the food available for bees. Remember this fact in February when doing the mid-winter check. If you lift the lid and the sugar is dry as a bone, have a spray bottle handy to dampen it a bit.
Another common question of beekeepers is, “Should I insulate my hives?” There are several places to get a good answer to this question. Each climate has its own challenges and best management practices. Good procedure for you is to ask several experienced local beekeepers who have good over-wintering success. Weigh their advice against what you can learn about bee biology and your particular conditions, and figure out what makes sense for what the bees actually need.
Another good place for information is the Bee Informed Partnership (beeinformed.org). This is a group that asks beekeepers questions about their beekeeping practices and success rates, so that we all can learn from what has worked, or not worked, for others. According to their information, those who use tar paper on their hives in winter have a better success rate than those who insulate. This makes sense for my climate in Colorado, where we have many sunny days in winter. The tar paper reduces heat loss to wind, and increases heat absorption on sunny days. Just be sure you don’t ….