James Masucci
Figure 1 legend: Most of us think about beekeeping in two phases. In the Spring, we are thinking about optimizing honey harvests. After that, we think about preparing for Winter. Preparing for Winter requires the colonies to produce healthy Winter bees. In my area, Winter bees are produced late Summer/early Fall when egg laying starts to decline. The bottom graph is the egg laying potential of the queen throughout the year. Because of the limited number of eggs that can give rise to Winter bees, it is important that our management decisions are geared at ensuring these eggs result in sufficient number of healthy Winter bees.
How do you make bee keeping decisions? Is it “WWJHD” (What Would Jerry Hayes Do)? Or…“My friend does it this way, so I do too”. How about, “This is what my bees need?” Do you ever stop to think about the long-term implications of your decisions? What we do today really impacts the colony 6 months from now, perhaps longer. I think we need to keep that in mind as we develop our beekeeping strategies. But what is the correct criteria to use?
I am going to make the argument that if we do what is best for Winter bees, then we are on our way to a successful year. I believe there are two critical time periods for beekeepers. The first is in the Spring when bees transition from Winter bees to Summer bees. The second is in late Summer/early Fall when the colonies are producing Winter bees. You see, Winter bees are special. Unlike Summer bees, which live around 6 weeks, Winter bees live for 4-6 months. These are the bees that live through the Winter and are responsible for getting the colony into the Spring build-up. Any stress that impacts Winter bees will increase the probability the colony won’t make it though the Winter. These stresses are the stresses everyone recognizes as being harmful to the colony: Pests, Pathogens, Poor Nutrition, Pesticides, and Poor Management. Thinking about these special bees when managing our hives will give us some criteria on which to base our management decisions.
I first gained an appreciation for Winter bees form Lloyd Harris, a beekeeper/researcher from Manitoba, Canada. He did his Master’s thesis studying the longevity of honey bees. Every 12 days throughout the year he painted a bunch of newly emerged honey bees and kept track of how long they lived. His results are quite telling. Most bees lived for 4-6 weeks during the beekeeping season, until about the third week of September (in Manitoba). At that point, the bees start living a long time. These are the Winter bees. His take home message was this…all those bees in your August colony will be dead by Christmas. Only the Winter bees will continue until Spring.
I was curious, when do bees in St. Louis, MO (where I am located) start making Winter bees? I had a high school student repeat the experiment in our bee yards. The results were cool…Starting around September 15th, a week before the magic Manitoba date, the bees stopped dying. Winter bees started to arrive mid-September. That means their eggs were laid the last week in August. I had her present to our local bee club and at the end of the presentation someone asked, “What are we supposed to do with this information?” Well, I submit to you that this information allows you to make informed decisions throughout the year. Numerous, healthy Winter bees means Winter survival. So I think of Winter bees when developing my mite control strategy, when setting up nucs, when requeening, when combining hives, and when feeding. Let me explain.
Simplistically, most of us of have two “beekeeping seasons” (see figure 1). In the Spring we are trying to optimize our honey crops. This entails getting the bees into Spring build up, managing swarms, and getting as many foragers as possible for the nectar flow. During this time of year, with maximal egg laying, plenty of food, and general beekeeping bliss, you can get away with a lot. The second season is preparing for Winter. This is where we do our post extraction mite treatments, feeding, and insuring everyone is queenright. During this time, mistakes on our end can easily lead to a dead colony by next Spring. On the bottom of figure 1 is the “egg laying potential” of the hive. These numbers are only directional. I use them in a population model that I built, based on Lloyd Harris’ results, my own experience, and some published bee models. Basically, in the Spring, once pollen starts coming in, the queen has the potential to lay a lot of eggs. Once the nectar flow is over and we head into Fall, she doesn’t lay as many eggs, colony population decreases and, ultimately, egg laying ceases with only winter bees surviving the Winter. It’s important to note that Winter bees are made during the time egg laying is declining. Which means the opportunity for producing these bees is limited. Which means we have to optimize that opportunity.
Even though “time of year” is a big determinant for brood potential, and there is nothing we can do to alter that (short of migratory beekeeping), there are several other factors influencing brood potential that we can manage. Some of these factors are: colony health (specifically, mite treatments), queen quality/health, colony population, and food availability. As we are managing these factors, we should keep in mind Winter bees as we make our decisions. We need to ensure a good crop of healthy Winter bees.
Colony Health:
Healthy bees live longer, including Winter bees. Knowing Winter bees are made late Summer/early Fall, we should focus our efforts to make sure our colonies are healthy at this time. The most meaningful health-related decisions relate to mite management. How many people treat once a year in Fall? I argue this is too late. High mite levels in late Summer mean Winter bee production is more likely occurring with higher viral loads. Higher viral loads mean a shorter life span. You should focus on keeping mite levels low before Winter bees are produced to minimize viral loads in the hive during Winter bee production. I have been able to accomplish this with a Winter OA vaporization. I am altering my strategy with the recent approval of two new mite control products, Norroa and VarroxSan, that give long-term mite control and are safe to use during honey flows. These make perfect options for Spring treatments which would result in low mite levels when we need it. We can then follow up with a Summer/Fall treatment to clean things up for Winter.
Figure 2 Legend: The prediction of my bee population model showing how many Winter bees a colony of a certain size on August 25 is capable of producing. The take-home message is that you can’t expect to have increasing hive populations in late Summer/early Fall. This helps you decide whether you need to add brood, combine hives, or walk away when trying to rescue colonies.
Queen Quality/Health:
Some beekeepers requeen every year, some never requeen. But queen quality can have a major impact on the number of Winter bees you can produce. Compare a spotty pattern, where maybe 60% of the cells produce bees to a great pattern where 90% of the cells produce bees. The good queen can produce 50% more bees than the poor queen. That matters. Remember, Winter bees are produced during a time of diminishing egg laying so every viable egg matters.
When is the right time to requeen? That’s a personal decision. However, thinking about Winter bees allows you to determine when the wrong time is to requeen. If you requeen with a mated queen, conservatively, you will see your first egg in 9 days (4 days in the cage and a few days to get into egg laying mode). If, like me in St. Louis, eggs for Winter bees start being laid around August 25, then the latest you should try to requeen would be August 16. Similarly, if you are going to use a queen cell, then the first egg is in 17 days the latest date would be around August 8. If you are going to let the hive make their own queen, first egg is around 22 days, and the latest date would be August 3. Having these simple guidelines can help you make better decisions. The later you are in the Summer, in the year the riskier the proposition. Perhaps requeening with a nuc is necessary.
Fixing Queen Less Hives/Colony Population
Requeening a queenless hive is not the same as requeening a queen right hive. A queen right hive has the appropriate age distribution of bees with all the castes fully represented and a certain amount of brood. A queenless hive is skewed towards older bees and will have less success raising brood because they won’t have the full complement of nurse bees. This is exacerbated the longer the hive has been queenless. When you realize that it takes 30 days to get your first bee when you requeen with a mated queen, you realize that most of the original bees will be dead by the time those bees emerge. It takes time for a colony to recover from that dynamic which pushes the “latest” dates described above back even further. It will be difficult to rescue a queenless hive in August without at least giving them some brood to help alleviate the old bee disparity.
As a mental exercise, think of a beautiful 20-frame colony. When you make the determination it is queenless, it has no brood, meaning it has been queenless for at least 3 weeks. The lifespan of the bees is about 40 days, and it is 30 days until the first bee from the new queen emerges. That means 75% of the bees die before bee population starts to replenish. At this point, you are down to a 5-frame colony. The size of a nuc (without a good population demographic). Does this colony have enough time to produce enough Winter bees to get through the Winter? It all depends on timing.
Figure 2 shows the results of my population model when I evaluate hive size on August 25 (Winter bee eggs being laid) with the number of Winter bees produced. Again, my model is just a model, and not super accurate. The conclusion is that colonies don’t get bigger late in the season. Usually, you can’t grow colonies late Summer. If you have a small colony, it’s going to stay a small colony. This tracks with my experience in my region. So, if that colony you requeened had about 5 frames of bees in late August, it will produce about 5 frames of Winter bees (10,000 Winter bees). Is that big enough? It depends on your region and your experience. The important thing is you can think about this before you make your decisions. In the Spring, you are fine, in the Summer, adding brood may be important. Always keep in mind the impact of what you do on the number and health of Winter bee production.
Feeding:
If there is no food available, brood production shuts down. If there is too much food available, cells get backfilled with nectar and brood production shuts down. Every Fall, we walk this tight rope trying to ensure our colonies have enough stores for the Winter. Several years ago, friend and Manitoba beekeeper Daryl Wright told me the story of how many Canadian commercial beekeepers shot themselves in the foot preparing for Winter and paid for it with super high colony losses. Many of their workers came in on visas and had to leave the country by Oct 1. Because of the loss of work force, beekeepers prepared their hives for Winter in September. They filled them with syrup and wrapped them up. What would a Winter bee mindset tell you would happen? They filled their hives up too soon which shut down brood production. Not enough Winter bees were made because the queen shut down early. Hence, high colony loss. The goal with feeding is to sustain normal activities in the colony and you want to fill them up in a way that does not negatively impact Winter bee production.
Beekeeping is complicated. There is a reason most new beekeepers give up after 3 years. As a mentor, I get asked a lot of questions about what people should be doing with their bees. My answers are never simple. It usually starts with “that depends”. I usually try to describe all the stuff going on in my mind that leads to the advice I am going to give them. The bottom line is that I have a set of criteria that I use to base my decisions on. Even in their most abstract way, I can trace them back to the simple question, how will this impact the future Winter bee population. I’ve given a few examples here. Rest assured, there are more. Try this exercise. Think of some scenarios in your bee yard and think about how your decision would affect Winter bee production. See if it doesn’t start making sense.
