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Mating Biology of Honey Bees a Colony When a New Queen Must Be Pro- the Former Head of the German Bee Research (Apis Mellifera), a Book We Coauthored with Duced

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Mating Biology of Honey Bees a Colony When a New Queen Must Be Pro- the Former Head of the German Bee Research (Apis Mellifera), a Book We Coauthored with Duced few years ago, I had the distinct plea- about producing a revised English version bility is to produce offspring (Ellis, 2015c). sure of meeting Drs. Niko and Gud- of their German book. Thus, work com- There are times in the normal lifecycle of A run Koeniger. Dr. Niko Koeniger is menced on Mating Biology of Honey Bees a colony when a new queen must be pro- the former head of the German bee research (Apis mellifera), a book we coauthored with duced. This occurs when a colony swarms institute in Oberursel, Germany and profes- Dr. Larry Connor of Wicwas Press. Much (Ellis, 2015a) or when a queen is lost for sor of biology at the Goethe University in of what I share in this article is taken from whatever reason (death, maimed, etc.). I will Frankfurt. Dr. Gudrun Koeniger worked as our joint book. (Caution: shameless self- not spend any time in this section discussing a research scientist and editor of the inter- promotion follows.) Feel free to read the what leads to a colony’s decision to make a national bee journal Apidologie. Both have book to discover more information on the new queen, but rather I will discuss queen devoted a lifetime to the study of honey bee mating biology of honey bees if this topic development from egg to sexual maturity. diversity and biology. Among other things, is of interest to you. The full citation for the Queen honey bees result from fertilized they worked tirelessly to decipher the intri- book can be found in the reference section eggs that are destined to become female, but cacies of honey bee mating biology. Their at the end of the article. not otherwise predetermined to be either a work culminated in a book on the topic writ- queen or a worker. The decision to make a ten for German beekeepers. The book is en- Rearing and sexual maturation of queen female larvae a queen or worker lies with a titled (English translation) Mating Biology honey bees colony’s worker bees. Worker honey bees and Mating Control. Typically, honey bee colonies are headed in the nest take a female larva that emerges In 2014, Niko and Gudrun approached me by a single queen whose primary responsi- from a fertilized egg and direct her to roy- (l) Figure 1. A queen larva floating in a pool of royal jelly. The queen cell remains open (uncapped) as the immature queen develops to adulthood in her cell. This photograph was taken from the bottom of the queen cell. In nature, the cell would be turned such that the opening would face down, with the queen developing suspended from the royal jelly above her. Photograph provided by Niko and Gudrun Koeniger. (r) Figure 2. A queen bee emerging from a queen cell. This photograph is oriented correctly, showing the queen emerging upside down from her royal chamber. Photograph provided by Niko and Gudrun Koeniger. December 2015 1293 ABJ_December_2015.indb 1293 11/2/2015 2:28:07 PM The first emerging queen has hit the jack- pot, of sorts. She is first in line to inherit the nest and the colony of bees it contains. If she is successful, she will be fed, groomed, and otherwise pampered daily as she progresses through a life that is many times longer than those of her sister workers and eventual off- spring. However, she has some work to do before she can receive her inheritance. Newly emerged queens seek out and eat the food necessary to power their upcoming activities, the first of which involves getting rid of the competition. As you might imag- ine, a colony does not usually attempt to rear only one queen when they intend to swarm or otherwise need a queen. Instead, they in- vest in the production of dozens of queens, all of which are developing alongside the first queen to emerge. The first queen to emerge, consequently, becomes a stealthy assassin who searches for her developing sister queens so that she can eliminate the Figure 3. Queen cells on the bottom of a brood comb. A queen emerged nor- threat they pose to her impending assenta- tion to the throne. mally from the cell on the left, this evident by the fact that the cell is opened A newly emerged queen will begin check- at its tip. The newly emerged queen then proceeded to bite holes in the neigh- ing all of the brood combs in the nest, doing boring queen cells, insert her abdomen in the cells, and sting her competition this at a high rate of speed. She is search- to death. Worker bees further widened the holes in the cells and removed the ing for two things: (1) already emerged lifeless contents. Photograph by Keith S. Delaplane. queens and (2) queen cells containing yet- to-emerge queens. When she encounters alty by feeding her more and better quality 600-fold during their first six days of life. the first threat, she begins to fight the queen food (royal jelly – Figure 1) than that fed Queen honey bees develop in peanut hull- until one of them is stung, dies, and is re- to her sisters who are to become workers. shaped cells that hang vertically from the moved from the nest by undertaker workers. This they can do because the female larvae face or periphery of the brood comb. This During intermittent battles with any adult remain bipotent (can become either queens means that the developing queens hang up- queens she may find, the new queen turns or workers) up to 48 hours after emerging side down while maturing. It takes a queen her attention to her immature sisters devel- from their eggs. Caste determination of the about 16 days to develop from egg to adult- oping in queen cells. When she finds queen female larvae becomes final on the larvae’s hood, this likely because of the large vol- cells, she will bite a small hole in the side of third day after emergence, at which time ume of good food she receives while young. the cells, insert her abdomen, and sting her the workers begin to offer the developing When she is ready to emerge, the queen will helpless sisters to death. These cells, then, monarchs copious amounts of royal jelly. use her powerful mandibles to cut through are opened from the sides and the lifeless This rich food ensures rapid growth of the the cell capping, and emerge upside down contents removed by the colony’s workers. developing larvae, whose weights increase into the colony (Figure 2). You can always tell when a queen cell has been attacked by a new queen because it will contain a large hole in its side (Figure 3). Virgin queens will repeat these behaviors until all of their competition is eliminated and only one queen remains in the nest. The surviving queen remains in the hive over the next few days. During this time, she surveys the combs, eats, and continues to mature. She even enjoys long periods of rest and food on demand, provided to her by her ever growing retinue of attendant workers. This time of rest and development is neces- sary given that she is not sexually mature at emergence. She needs more time for her flight muscles, ovaries and spermatheca to develop. The latter play an important role in queen reproductive biology and were re- viewed in my September 2015 ABJ article (Ellis, 2015b). It will be useful to refer back to this article once I begin to discuss mating biology below because some of the discus- sion of what happens inside the queen after mating will get a bit technical. The newly emerged queen is quite ac- Figure 4. The everted drone endophallus. A drone’s endophallus is the equiva- tive. She will run through the nest, a be- lent to the mammal penis. The endophallus is stored, inside-out, in the drone’s havior that may even be encouraged by the abdomen until use. At this time, much of the drone’s hemolymph (blood), workers who are increasingly aggressive rushes into the endophallus to force it out of the drone’s body and into the toward her around the second or third day. queen’s sting chamber. Photograph provided by Niko and Gudrun Koeniger. Around this time, worker bees nip (bite) 1294 American Bee Journal ABJ_December_2015.indb 1294 11/2/2015 2:28:09 PM at the young queen, thus encouraging her to run throughout the colony. Also during this time, the queen is likely to encounter any queen cells or emerged queens that she failed to find during her first colony search. The queen reaches sexual maturation around 22 days after being laid as an egg (6 or so days after emerging from a queen cell). A queen’s behaviors change considerably once she reaches maturity. Rearing and sexual maturation of drone honey bees Drones are the other reproductives in the honey bee colony. They are not participants in the social activities undertaken in the nest. Rather, their sole purpose is to mate with a young queen. Consequently, they are valued during the reproductive season, but are otherwise viewed as useless during the fall/winter when no new queens are being produced. This truth is best demonstrated by the late season phenomenon that occurs when worker bees force drones out of the nest so as not to waste resources to maintain Figure 5. An illustrative view of the male-biased ratio in honey bee reproduc- a group of bees that will not help the colony tives.
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