American Bee Journal • October 2019 Vol. 159 No. 10 • Beekeeping, Past and Present: Using Naturally Built Queen Cells

Naturally-built, well-constructed queen cells from good bee breeding stock can be a source of new queens in a beekeeping operation. To use these queen cells, beekeepers should know to how judge good queen cells from poor ones, how to cut queen cells from combs, how to transport queen cells between apiaries, and how to reattach queen cells to the combs of the recipient colonies. With the high cost of queens, these skills would be very beneficial for beekeepers to produce some queens on their own.

As part of our general biology of queen cells, let’s briefly review some basic queen cell biology and beekeeper terminology. Queen cells occur naturally under three conditions: when bees prepare to swarm, to supersede a failing queen, or from emergency queen loss. Queen cells reared under these three conditions are referred to respectively as swarm cells, supersedure cells, and emergency queen cells. When swarming, bees build numerous swarm cells near the edge of the brood comb. There are plenty more swarm cells over the face of the comb, most likely in locations where queen cells will fit between the combs. In contrast, bees superseding their queen typically build a few queen cells near the central region of the combs. The two categories can be nebulous. A colony, typically in the spring, can start out with a few supersedure cells and later on use them to swarm.

Swarm or supersedure cells usually begin from queen cell cups. A queen cell cup is a precursor of a queen cell, consisting only of the cell’s base and about a third of the cell’s wall (see Figure 1). Queen cell cups are usually present in the brood nest for most of the active season; however, they are generally empty except during swarming and supersedure. When containing a fast-growing queen larva, the bees build the queen cell cup into a queen cell (see Figure 2). In contrast, if the queen dies suddenly, the bees are forced to begin the emergency queen cell by enlarging a worker cell containing a young larva. Unlike the queen cell structure in Figure 2, emergency queen cells have cavities extending to the original worker cell floor (the foundation). As we will see later, this deeply rooted cavity presents a difficulty when removing an emergency queen cell from the comb.

From egg to adult, the queen develops in about 16 days. Although the larva is female, the production of an adult queen or worker is determined by the larva’s diet. The diet for queen formation is commonly called royal jelly and differs from the larval diet of the worker bee larvae. When the nurse bees finish provisioning the queen cell with royal jelly, the bees build a wax dome-shaped cap across the cell’s opening. Now the cell is referred to as a “sealed” queen cell (see Figure 3). For about a day after her cell is sealed, the queen larva continues to feed on stored royal jelly, quite unlike the worker and drone larvae who do not have anything like this massive food reserve. Before transforming to a pupa, the queen larva spins a partial cocoon (concurrent with postcapping feeding). A queen cocoon is quite unusual because it does not completely surround the queen pupa. The cocoon extends across the cell’s cap and up the sides, but not across the base of the cell, which would separate the queen larva from her food supply (see Figure 4). Prior to the queen’s emergence, typically the bees will remove most of the wax cap and expose the end of the cocoon (see Figure 5). The presence of an exposed cocoon can be used to distinguish a queen cell that has been sealed for some time from a newly sealed cell (with a wax dome). Besides wanting some indication of when the queen will emerge, newly sealed queen cells should not be handled. Apparently the spinning larva is quite susceptible to temperature fluctuations and physical shocks. When the queen is ready to emerge from her cell, the queen cell is referred to as a “ripe” queen cell.

When learning about queen cells, we see them in one particular way, which is so obvious, it becomes subtle, and then beyond question. We see queen cells in reflected light. To better reveal the structure of queen cells, let’s look at queen cells in transmitted light, where the light comes out of the queen cell (transmitted through the cell). In Figure 6, I have removed the contents from a sealed queen cell, installed a small light source, and photographed the queen cell in the dark. Now the braided pattern becomes more pronounced. The random ridges of wax appear woven around the sides of the queen cell. The pits on the queen cell glow because their bottoms are just the queen’s cocoon and some thin wax. The cap end of the cell glows brightly because it is only the queen’s thin cocoon since the bees removed the wax cap (and my little light source had more light aimed to the cap. Currently, I’m looking for a better light source, subject to several technical parameters.) When the queen emerges, she has only to snip through the cocoon, not chew through a thick layer of capping wax as shown in the next revealing photograph.

Figure 7 shows a sealed queen cell that was recently capped, as indicated by its thick wax cap. Even the wax braids seem thick and heavy with no obvious pattern. In Figure 8, I am comparing my lighting technique on a pair of joined queen cells. The left queen cell is in regular reflected light as we see it in the usual way. On the right, the queen cell is in the same reflected light –– plus it emits transmitted light. The queen-cell pits on the left cell appear inconsequential and unimportant. The lighting of the right queen cell indicates the thinness of the bottoms of these pits. The glow from the pits helps one understand how worker bees and queen bees could put their antennae into the pits to determine if the queen inside is alive, and to perceive maybe even her age. The thin-bottom pits could be like “olfactory windows.”

While seeing the queen cell pits in transmitted light appears to be novel, the idea about bees using them to perceive queen cell contents has been around for a long time. In addition, I know a virgin queen can tell if a queen cell contains a live queen. Many times I have found her with several destroyed sealed queen cells and a couple others intact, appearing ready to emerge. Those queen cells are not viable. She knows it, and my rule is not to use those queen cells. I cannot remember the virgin queen ever being wrong, provided the bees did not interfere with her (so not during after-swarming because then the worker bees regulate queen emergence.) My humble rule is a queen can tell what is in a queen cell better than I can.

Whether the queen cells were built in response to swarming, supersedure, or emergency queen loss, only the best cells should be to produce new queens. The egg-laying capacity of these new queen bees will vary, in part, because of differences in their developmental environments. For example, queen larvae that received generous amounts of royal jelly grow larger, and as queens, are expected to have a larger egg-laying capacity. Some of the differences in the queen’s developmental environment show up in the size and the appearance of her queen cell. Therefore it is important to be able to distinguish good queen cells from others by their appearance.

Queen cells vary in size, and in judging queen cells, size is very important. Larger queen cells generally indicate a better developmental environment of the larva. Therefore, larger queen cells are better than smaller ones. For example, Figure 9 shows a size comparison between a small queen cell reared under emergency queen loss conditions and a large queen cell reared under supersedure conditions. If a queen cell that small is opened and the pupa is removed, very often, little or no excess (old) royal jelly remains in the cell. The lack of excess food can indicate that the former larva may not have been properly fed, and may result in a poor queen. In contrast, the larger queen cells typically during swarming or supersedure contain excess royal jelly, i.e., more royal jelly than the larvae could consume. Most likely these larvae were properly fed. By the time the queens emerge, the previously glistening white royal jelly will appear as a gooey reddish-brown substance at the base of the cell. Seeing that material in an old queen cell still indicates the queen larva was well fed. Now that we know about judging queen cells, the next step is moving them.

Although an entire frame with naturally- built queen cells can be transferred between colonies, usually it is more efficient to cut the queen cells from the combs of the donor colonies and attach them to the combs of the recipient colonies. Eventually this manipulation will be required because the queen cell donor frames will not match the number of receiving colonies. In addition, sometimes I must transport the queen cells to recipient colonies in another apiary. It is easier to move the queen cells in a small padded box near the heat vent of the truck, rather than move several frames and replace the frames in the donor colonies.

To begin, I move only sealed queen cells between colonies, because obviously the bees have finished provisioning a sealed queen cell with royal jelly. As mentioned above, I do not move newly sealed queen cells with spinning larvae. Seeing the fibrous cocoon at the end and sides of the queen cell tells me the queen cell can withstand some reasonable handling as described in the next article.

Unsealed queen cells, containing feeding larvae, should not be moved because the recipient colony is usually weaker, a nuc, or queenless, etc. The weak colony may not finish provisioning the queen cell with a generous amount of royal jelly. In addition, a queen cell with a larva is extremely delicate near its opening. Deform or dent the circular opening to the larva, and the bees may destroy the queen cell.

Removing a queen cell from the comb gets easy with a little practice. I use my pocketknife to cut, being careful not to expose the developing queen or to dent the cell. Queen cells constructed from queen cell cups are usually easier to remove from the comb than are emergency queen cells. As noted above, the cavity of an emergency queen cell originates in the floor of the worker cell (i.e., the foundation). In order to separate the emergency queen cell from the comb without exposing the developing queen, you must cut out a plug of the underlying comb. That is not only messy, but it can be quite difficult if one encounters reinforcing wires or plastic foundation. Therefore, I rarely use emergency queen cells in producing new queens. Of course one could resort to moving the entire frame with the emergency queen cells on it to queen-start a colony, perhaps choosing the best cell by eliminating the others.

In contrast, the cavities of queen cells built from queen cell cups only extend to the former queen cell cups, which are not very deep in the brood comb. In most situations, these queen cells only extend a little into the face of the brood comb, making their removal easy. The cutting also avoids foundation wires, which are deeper in the brood comb. So swarm and supersedure queen cells are usually well constructed and easy to cut from the brood comb as compared to emergency queen cells. I recommend beekeepers practice cutting queen cells from combs that would be otherwise destroyed, even removing unsealed ones, just to increase your skill level.

In the next article I will share more innovative things I do with queen cells that beekeepers should find useful with their apiary work, like transporting queen cells safely and reattaching them to the combs of the recipient colony. I am also going to share something rather novel that I have done for decades.

Dr. Wyatt Mangum, author of Top-Bar Hive Beekeeping: Wisdom and Pleasure Combined, is an internationally known top-bar hive beekeeper, who started keeping bees at age 10. He switched all his colonies to top-bar hives back in 1986, long before it became popular. He is also an apicultural historian, who blends his knowledge of beekeeping history with his study of honey bee behavior. email: wmangum @umw.edu. www.TBHSbyWAM.com