Keeping colonies alive in winter has become more difficult since the advent of Varroa destructor. I also believe that we now have tropical African genetics in all of our bees. These characteristics are recognizable. Some bees are extremely defensive and more prone to swarm or abscond. One thing about these tropical bees, they do not have the best genetics for living through the winter in the U.S. or Canada.
This past winter was a disaster here in the middle of the country for my bees. The winter was as cold as the winters during the 1970’s and 1980’s. Those winters were not as difficult for the bees kept here at that time, but today, the bees are different. We had three hard freezes here when the temperatures dropped into the single digits at night. This is the mid-south-central United States where our snow cover only stays a few days at most. I was able to check on the bees during a warm period after each cold spell. The clusters were noticeably smaller after each deep freeze. All the bees were alive after the second freeze. All colonies had ample food stores. The third freeze killed half the colonies and left the remainder weak. This was the worst winter loss I have had in 30 years keeping bees in
this location.
Overwintering bees has become one of the most difficult tasks for beekeepers throughout the country. At this time, even if everything is done to help bees get through winter, there will be winter losses. All we can do as beekeepers is to minimize the damage. Strong colonies over winter much better than weak colonies; cluster size is critical. This involves keeping colony numbers as high as possible in the fall.
If stimulated by food gathering, queens will continue to lay eggs until December in this area. One strategy I use is to feed bees a 50% solution of sugar in water. I include a pinch of salt. Fall feeding is not a matter of filling a quart jar for the entrance feeder. Think in terms of gallons for each overwintered colony. My bees will receive 3 or 4 gallons of sugar syrup each in the fall as fast as they will take it.
There are several easy methods to feed bees. Entrance feeders work. In fall use two for each colony entrance. That is a half-gallon of feed so fill them 6 times. I have some gallon and half-gallon jars and put those on with a hive cover that has a 2 3/4 inch hole for the jar lid with feeder holes in it. External jar feeders are easy to see and easy to fill. Another method that is easy to use is gallon zip-lock bag feeders. Place the gallon bag full of syrup on the top bars. Cut through the air bubble that comes to the top with a utility knife. Place a shallow super rim around the feeder and put the hive cover over all.
There are also division board feeders, but these take up the space of two frames. Comb honey-producing bees need their frames. Feeding in the open gives the most feed to the strongest colonies, but any form of feeding bees in fall is far superior to not feeding them in preparation for winter.
In the far north, wrapping hives is common. Insulation on the top of the hive is particularly important as heat rises. Some U. S. beekeepers are beginning to adopt the European practice of keeping bees inside over winter. I have seriously considered constructing an indoor apiary. Keeping cold winter wind off the bees is very beneficial. A winter cluster of bees is a warm blooded, endothermic colonial organism; subject to wind chill. Controlling the wind chill factor might have saved my bees last winter.
Successful overwintering is best accomplished with strong colonies. Strong colonies with a lot of bees require a lot of room. Even in the South Central United States, it is more challenging to over-winter colonies in a single hive body. Two are better. We have talked previously in this column about combining colonies for winter. It does require at least one new queen for every colony in the next year. The effect is protection from winter cold. It is a combination of hive pests, shorter bee life due to disease and winter cold that causes colonies to shrink into a cluster too small to survive winter.
I will not exclude pesticide effects from possible winter losses. We must examine the facts more closely. Pesticides, especially insecticides, adversely affect bees. Often the crop oil, detergents and other adjuvants used in or with crop protection chemicals are detrimental to bees. My bees reside in an area where there are literally millions of acres of crops. All are treated with herbicides, insecticides and fungicides. The fact is, that beekeepers in the mountains west of here are hundreds of miles from any pesticide application. However, their winter losses are as bad or worse than mine.
Treating bees with chemicals to control Varroa mites hurts the bees, but is likely better than …