How do Bees Survive the Winter?
Bees are so amazing! Winter bees are bigger, stronger, and live longer than the average worker bee. Read more about how them and how they help a bee colony to survive a long, cold winter.
Long Live the Diutinus Bees
Diutinus means “long lived” in Latin. Diutinus bees, or winter bees, play a crucial role in the survival of a bee colony over the winter. In comparison to worker bees, diutinus bees (aka winter bees) have a much longer life span; they can live up to 6 months!
Winter bees are bigger, fatter, and amazing – let me tell you more! But first, you should have a little fun learning how to say “diutinus” – it’s a lovely word! According to Wiktionary, you can say the word one of two ways: /diˈuː.ti.nus/ is the classical way to say the word, but the ecclesiastic /diˈu.ti.nus/ is well accepted. It’s all in the length of the vowel!
As the growing season begins to come to an end (August in New York), the bees are already thinking about winter survival. The nurse bees starts feeing the larva a special low-protein diet that results in the winter bees. Winter bees have many important roles, but foraging is not one of them; their job is to help the hive survive during the extended period when forage is not available to them.
Bees are smart. The trigger for the bees to start producing winter bees is actually not colder temperatures, but the availability of pollen. So, when your flowers stop blooming and the weeds slow down, the nurse bees begin to feed the larva a special diet, and the queen slows down.
Fat Winter Bees and Fat Bodies
Winter bees don’t really appear any different than summer bees, but internally there are a significant higher presence of fat bodies. Fat bodies are essential bee organs packed with nutrients that are crucial for the bees survival, particularly when they cannot get out to find fresh forage. They’re a little similar to the human liver, where we store carbohydrates as glycogen stores for energy when there is no time to refuel, like when someone is running in a marathon.
Vitellogenin
Vitellogenin is a protein synthesized inside the fat bodies of these winter bees (it’s actually found in all bees, and even other animals) that help them live longer and work harder. Because the winter bees have more fat bodies, they also have more vitellogenin than springtime bees.
Vitellogenin is technically a glycolipoprotein– that means it has little bit of sugar (glyco, 2%), fat (lipo, 7%), and protein (91%). Beekeepers want to send the bees into the winter with plentiful stores of honey and pollen in the hive, but vitellogenin is a packed pantry of protein inside the winter bees bodies. That 91% of protein is essential as spring approaches; ‘baby bees’ need protein to grow!
The high levels of vitellogenin (remember: 91% protein content) inside winter bees helps them to raise the brood that will become the first generation of spring bees. As nurse bees, they can draw from their own body stores and secrete protein rich brood food even in the absence of fresh pollen! In this way, the bees are emerging and ready as the very first spring sources of nectar and pollen are beginning to bloom.
Vitellogenin also enhances the immune system, which is important for bees and humans alike, when they are cooped up inside for extended periods of time. Man cannot live by bread alone…nor can bees live on honey alone. Honey is a source of micronutrients for bees but both humans and bees also need some protein and fat to be healthy.
Thermoregulation
Winter bees help to control the temperature inside the hive. Research shows that regardless of the outside temperature, the in-hive optimum temperature needs to be ~ 95 °F for a bee colony to survive. To prepare for winter, the bees will first seal all the cracks and gaps and any forms of opening in the hive.
The bees form a compact cluster and position themselves to keep the heat inside their living area. They generate their own heat using their bodies through forced shivering; they contract the muscles they would typically use for flight. Fanning their wings helps to circulate the warm air.
Fluctuations in the temperature may cause the bees to “break the cluster” which can be fatal to the bees. When this happens, bees can die, even when there is plenty of food available.
Population Decrease
Another way bees survive the winter is to decrease the number of bees living in the hive; the bees have a few ways they accomplish this. . All of the drones (male bees) are ejected from the hive at the end of autumn. They serve no purpose in the winter hive and would only be a drain on the hive resources. In one of those wicked moves of nature, the drones are either killed or sent out into the world to fend for themselves. Either way, they will perish.
The Queen bee also slows down on her egg production and eventually the hive will be broodless. Again, more brood would mean more mouths to feed and a high population of bees would quickly use up the honey supplies. The last eggs of the season will be fed a low -protein diet and become the long lived winter bees that can survive for up to 6 months (September – February). The Queen won’t start laying again until mid-January.
The queen bee is the longest living bee in any beehive. Her lifespan is typically between two and three years, although she can live longer. She will be attended to and treated as royalty by all her worker bee attendants, as long as she is productive. A productive queen lays up to 2,000 eggs a day; without a laying queen, a hive will quickly perish.
In comparison to the queen bee, the average bee has a life span of about 6 weeks. Just like humans, some bees have jobs associated with higher risks. Forager bees that fly out to search for sources of nectar and pollen face the most hazards. They can damage their wings while flying through a brushy area and be unable to make it home. They may get lost. They may get eaten. There are a lot of hazardous working condition as a worker bee.
Summary
Nature is amazing and adapts to the environment in such fascinating ways. When I think of the size of a honey bee, their internal their organs, like fat bodies, and the glycolipoproteins inside those teeny tiny organs, I am in awe! I hope you are too!
Honey stores are crucial and that’s a reason we always leave our Backyard Bees bees with plenty of honey in the winter. But they also need protein. And they also need to be ready to start out in the springtime. The winter bees help with all of these thing, and so much more!