Often, when talking to people about our bees, I get asked what the bees do during the winter. The answer is pretty amazing, really.
A bee born in the spring will generally live for around six weeks, but a bee born in the late fall can live for up to four months. The reason for this is that over the cold months, the bees’ metabolisms slow down, preserving their energy and, as a result, slowing the aging process.
Bees are experts at regulating the temperature in the hive. In the summer, that means bearding and fanning to cool things off. In the winter, that means sealing the hive with propolis (bee glue) and forming a cluster. Bees cluster when the outside air temperature dips below around 57 degrees. (I have sometimes seen the bees out flying when it is slightly cooler than that.) The cluster keeps the queen and any brood present at the proper temperature, between 85 and 93 depending on the status of the brood nest. The cluster needs to maintain contact with the stored food or they can starve to death even if there is plenty of honey in the hive. If it gets really cold outside, the bees may enter torpor, a sort of suspended animation in which their metabolism slows down so much that they require little fuel and look dead. Their are plenty of videos out there of people breathing bees “back to life” by bringing them out of torpor.
Winter Hive Setup
Since temperature isn’t really a problem for bees most of the time, the really issues are 1) mites and 2) moisture.
The Varroa Destructor Mite is the probable cause of many colony collapses because the parasitic mites deplete the nutrition vital to winter bees and also spread disease. It is vital to get the mite situation under control before the queen is rearing the winter bees so that the cluster is as healthy as possible. I treated our bees with Apivar and Formic Pro during the year. Before closing the hive up for the winter, I also did an Oxalic Acid Drip to try to get rid of as many mites as I could. I feared that the extended bit of warm weather we had, which lead the queen to keep laying a decent sized nest, meant the mites would keep breeding too. Having a large cluster is great, but as the bee population starts to decline, the mites could overtake them. So, I hope that worked.
Colorado is a pretty dry climate, so I am not very worried about moisture, but too much moisture in the hive can be disastrous to the bees. When they generate heat for themselves, some condensation is created and some is needed. Bees, like all living things, need water. But if too much builds up, it can drip on the bees and/or lead to mold, both of which are very bad. To control moisture, I put a quilt box on top of the honey super. The quilt box (purple in the picture) has a thick layer of pine shavings from the chicken supplies that will absorb moisture. It also features screened vents to allow ventilation, another form of moisture control. Under the quilt box, I have a feeding shim (blue), which will allow me to add a layer of dry sugar (Mountain Camp Method) later in the winter as emergency feed. The dry sugar will also absorb moisture in the hive. If I put it in too early, though, the bees will just haul it out like trash. Many beekeepers tilt their hives forward about 5 degrees to allow water to run out of the hive, but I cannot figure out how to do that with my hive stand. Given the dry climate and the quilt box, I hope that this setup works.
Finally, there’s a mouse guard and it’s all strapped to gether with a ratchet strap with some heavy rocks on top. This setup held it all together during 85 mph winds yesterday!
It’s our first winter with the bees and I have so enjoyed them this year. I really hope that they make it through the winter. The requeening late in the season made me nervous, but the long stretch of warm weather gave them a leg up, I think. I fed them 2:1 syrup along the way so that they didn’t have to break into their stores. At the last inspection, I estimated that they had about 100 pounds of honey stored, plus plenty of pollen. I’ve seen them out taking “cleansing flights” (to go to the bathroom) and dragging out dead bees on each warm day, and I get a little thrill every time.
Good luck, bees! I hope to see you in the spring. -Kasey
Scientific Beekeeping: Fat Bees Part 1