Fat Winter Bees-Why You Need Them
Winter Bees – Fat & Healthy

Winter colonies need a good population of fat Winter Bees.

Your calendar says we have a few more months of Winter. However, inside the bee hive our worker winter bees are producing new brood. And, that’s a very good thing. Our hives need a population of new bees and soon!
Why? Because our Winter Bees are reaching the end of their life cycle.
Different Types of Worker Bees
You see, Winter Bees are different than Summer Bees. The tasks performed by the worker bees during their lives are different as well. Brood rearing is greatly reduced during Winter. Most queen bees will cease egg production for several weeks.
With no bees being produced, the number of adult bees in the colony will slowly drop over Winter. Winter worker bees need to live longer than their Summer sisters. Otherwise, the colony would fail before new bees emerge in February/March.
Tasks of the Summer Worker Bees vs Winter Worker Bees
If you are a worker bee that lives in the warm months of the year, you will enjoy about 6 weeks of life. The first 3 weeks are spent on duties inside the hive, the last 3 are spent foraging for food.
Summer worker bees literally work themselves to death for the benefit of the colony. Wings become tattered and the fuzzy hairs wear off their bodies. Yet they continue to work until death. Honey bees do not repair broken parts through cell repair. Once their body parts fail, they are finished.
The tasks of Winter bees are different. Winter bees spend most of their lives inside the hive. Foraging outside the hive is not important during Winter. Most nectar and pollen sources are unavailable during cold weather. And the cold-blooded bees cannot fly in cold temperatures.
Instead, these bees spend time tending to the queen and helping regulate hive temperatures. Once brood rearing resumes, they care for brood to produce new spring bees. These new bees will carry the colony into the new season.
How Winter Bees are Different
A Winter bee is physiologically different than honey bees produced in Summer. They have enlarged fat bodies in their abdomens and heads. These fat bodies produce vitellogenin. Vitellogenin increases the lifespan of bees and boosts their immune systems.
Bees with high levels of vitellogenin are able to store protein reserves. This enables the colony to begin brooding up without a lot of pollen. The quality of jelly fed to larva is determined by the vitellogenin levels of the nurse bees.
Colony Production of Fat Winter Bees
During Fall, the honey bee colony is very busy foraging for last minute food provisions. Winter is coming and the bees must collect nectar and pollen while they can. Brood rearing slows or stops completely during the winter months. The focus of the honey bee colony changes from growth to survival.
Researchers disagree on the exact trigger for the production of Winter Bees. But the production of healthy winter bees takes place during the last few brood cycles of the year. The exact time will vary somewhat depending on your climate.
As brood rearing slows in the Fall, emerging bees consume an extra quantity of pollen.This protein is stored in their bodies (Fat Bodies). Honey bees store pollen in their comb for use during Winter. In addition, the fat bodies of Winter bees provide protein to aid in the production of brood.

Fat healthy winter bees are able to live through the cold months and produce new young.
Healthy Winter Bees Are Vital
A Winter bee is not an endless supply of resources. Fat bodies located inside the bee will shrink once brood feeding begins. I am sure you can understand the importance of having healthy Winter Bees. The health and lifespan of your winter bees is affected by nutrition deficiencies and heavy varroa infestations.
Studies have found that colonies with varroa mite infestations do not fully develop into typical long-lived Winter bees.Poor quality Winter bees are unable to provide sufficient food to new larva. They will also die sooner and may result in the colony perishing before the end of Winter.
If we have a Winter colony that is low on food stores, we can feed them. However, we can not make the bees live longer. The survival of the honey bee colony depends on having a good population of healthy Winter bees.
This is yet another reason to get varroa mites well under control before Winter bees are produced. In my part of South Carolina, I want to have successful varroa mite treatments completed prior to August 15.
In Conclusion:
Strive to have healthy nurse bees in the hive raising your long lived cold season bees. Good nurses will produce good Winter bees with well-developed fat bodies. If varroa are a problem in your hives, treat early. Waiting until late Fall may kill the varroa on the bees and that is good. However, the damage has already been done and you may be going into Winter with skinny bees.
Beekeeper Charlotte