The winter solstice: day one of bee season

Inside: Learn how bees are affected by changes in day length and why the winter solstice marks the start of the new bee season.

Day length affects bee behavior

Here in the northern hemisphere, your calendar may tell you it’s the first day of winter, but from a bee’s perspective, it’s the first day of the new season. Like many plants and animals, bees are affected by changes in day length. Immediately after the winter solstice, when the hours of daily sunlight start to increase, the colony begins to change and bee season begins.

How the bees assess the day length is not clear, after all, they live inside a dark cavity. However, within a few days of the winter solstice, the worker bees slowly begin to raise the temperature of the brood nest from a cool resting temperature of 70-75° F (21-24°C) to the brood rearing temperature of about 95°F (35°C). This increase in warmth spurs the queen to lay eggs. She will build a small brood nest and gradually, over the course of many weeks, increase the size of her nest. If all goes well, the hive population will explode with the first warm days of spring.

Winter is the first of two parts

The stretch from December to June is half of the yearly cycle. In temperate North America, the bee colony is at its smallest in late December. After the winter solstice, it gradually starts to rebuild. The queen lays more eggs, there is more activity in the nursery, and the population slowly increases.

By the end of June, most colonies are as strong as they are likely to get. Basically, the six months from late December through June are times of increase, with the summer solstice marking the apex.

The second part, from late June to mid-December, is the season of decrease. During the months of late June through late December, colonies in the northern hemisphere shrink, growing smaller and smaller until the shortest days of winter.

Bee populations from solstice to solstice

Sure there are variations and fluctuations depending on local climate, weather patterns, and individual colonies, but the trend is six months of increase and six months of decrease. I read recently that the response to photoperiod (increase or decrease of daylight) is much less in honey bees than in some other insects. But regardless of how it works, you can see the yearly fluctuations in your colonies.

Up through June, beekeeping is as easy as breathing. In most cases, the rate of growth in your hive is greater than the growth of most predators and parasites. You wonder, “What’s all the fuss about mites?” You don’t see them anywhere. “Are hive beetles and wax moths really a problem?” You wonder what’s so hard about raising queens, catching swarms, or making honey. Like a rising market, everything looks rosy. The whole beekeeping thing is a piece of cake.

Diving into nectar dearth

By the beginning of July, things start to change. Much of the continent is headed toward a nectar dearth. Almost imperceptibly the ratio of problems to bees shifts. Swarms virtually cease. The swarms that are cast are usually small or weak. Just as the poem says, “A swarm in July is not worth a fly.” Splits take longer to build up. It’s a little harder to raise good queens. Honey production slows to a crawl. Even flowers that are in bloom may have less nectar because rainfall has dropped and temperatures climbed.

New problems arise. Your bees spend all their energy fanning. Robbing honey bees appear out of nowhere. Marauding yellowjackets and hornets case your hives looking for a meal. Your sweet little honey bees suddenly become skittish and would rather you stay away. Your neighbors complain about bees in their pool and hummingbird feeders.

Like yellowjackets and wasps, mite populations continue to grow, even while your honey bee populations are dropping. Suddenly, it seems like there is a handful of mites for every bee. Weaker hives may be overcome with beetles. By August, workers are throwing out the drones in a last-ditch effort to prepare for the coming winter. Foraging continues as long as there is something to collect, but it is harder, consumes more energy, and takes more time.

To manage bees, think about the calendar

New beekeepers often ask why their bees are doing one thing just when they are expecting the opposite. If that happens, stop and think. Look at the calendar. Are your colonies in an increasing phase or a decreasing one? More often than not, a look at the date will help you understand what is going on with your colony.

Just remember that building occurs from the winter solstice to the summer solstice, and contraction occurs from the summer solstice to the winter one.

Also, keep in mind that the solstice is not like a switch. Bees are not one way on the 21^st and a different way on the 22^nd, but the change is sure to come. The seasoned beekeeper knows this intuitively, but a new beekeeper needs to be aware that change is in the wind. Remember: beekeeping doesn’t take much of your time, but your timing is everything. Mark your calendar in red.

Rusty
Honey Bee Suite

About Me

I backed my love of bee science with a bachelor’s degree in Agronomic Crops and a master’s in Environmental Studies. I write extensively about bees, including a current column in American Bee Journal and past columns in Two Million Blossoms and Bee Craft. I’ve endured multiple courses in melittology and made extensive identifications of North American bees for iNaturalist and other organizations. My master beekeeper certificate issued from U Montana. I’m also an English nerd. More here.