Winter Concerns

By Dr. Gordon Wardell, Chairman Project Apis m.  
December 23, 2015

The Holiday Season is a joyous time of year and yet a nervous time for beekeepers. This is the season when all of the efforts since the summer are realized. If not managed correctly earlier in the fall, colonies will begin crashing this time of year for a number of reasons making the Holidays less than festive. Wintering success starts in late summer. The most obvious challenge is mite control. If mites go unchecked too far into the fall, the bees that make up your winter cluster are compromised. The bees' life expectancy will have been shortened by Varroa mites and the viruses they vector, reducing a bee's potential life by as much as half. Summer bees have a life expectancy of approximately 6 weeks - they literally work themselves to death. But healthy bees destined for the winter cluster are different. A winter bee's life expectancy can be as great as four to six months. You can see why mite management in the fall is so critical. Shortening a winter bee's life expectancy by half would predict its demise in December instead of February or March. Early loss of population will make the colony susceptible to chill and even starvation because they can't move to the food when temperatures drop.

The greater longevity of winter bees is largely due to a storage protein sequestered in the bee's abdomen called vitellogenin. This protein, carbohydrate, lipid complex is the currency that keeps the colony going and rearing brood even in the middle of the winter.

This buildup of vitellogenin doesn't happen by accident; it's a delicate balance between colony population, available food stores, the queen's egg production and emerging workers. In the fall, as days begin to shorten, the queen's egg production begins to decrease. Soon the nurse bee-to-brood ratio shifts. There are still numerous workers emerging from brood cells, eating stored pollen (or protein supplement), becoming nurse bees and producing royal jelly as nurse bees do so well. But alas, there aren't enough larvae to accept all the royal jelly being produced because the queen is shutting down egg laying, so the surplus royal jelly is passed around the colony and internalized by the newly emerged bees. They "fatten up" much like a bear preparing for winter, but instead of hibernating, the bees are active, calling on the vitellogenin as added food stores, and it proves an essential resource when the queen resumes egg-laying in January.

Too many times we hear about the doom and gloom of what is wrong with our colonies but no suggestions about what we can do to help remediate the situation. So I'll take a stab at what we can do to help colonies that are sliding backwards this time of year. It's not easy, and there is no guaranteed fix. There are so many factors that could be playing into the colony's drop in population, but we do know a few things that can help.

You can reduce the colony down to a size the remaining bees can manage. Help them conserve heat. Feed them and make the food available to the cluster. A high carbohydrate (sugar) protein supplement patty or candy board placed near the cluster can provide the energy needed to keep the cluster warm, and the small amount of protein in the mix helps extend the life of the bees in the cluster. In bees, as in most animals, protein equals longevity. You can combine colonies as well, if you are worried about their survival. Stacking weak colonies over stronger colonies separated with a double screen can help the weaker colony by sharing heat with the stronger colony. Later in the spring they can be split apart again.

Another thing to watch for this year is starvation. The central and eastern parts of the country are currently experiencing unseasonably warm temperatures. This sounds counter-intuitive but warmer than normal temperatures could lead to colonies consuming their honey stores faster than expected leading to starvation when the cold temperatures do return. The problem is that when it is unseasonably warm bees are out foraging for resources that aren't there, burning up their honey reserves only to be caught short later. Monitor your colonies closely. Practice lifting the back of the colony to judge its weight and stores inside without having to open the colony.

Many experienced beekeepers will say that a colony is weak for a reason, and there is not much you can do to bring them back especially this time of year. However, when we are able to bring that colony back from the brink it makes us feel like the stewards of the bees that we want to be. I hope you all have a great Holiday Season and prosperous colonies in the New Year.