As an undergraduate student pursuing the Department of Entomology honors certificate, the central focus for my honors research project will be investigating what factors may influence wax production efficiency in honey bees. Effective wax production is an extremely critical part of a functioning honey bee colony, making it an important area to study. There have been studies done in the past to examine factors influencing wax production, such as individual bee age and seasonality. However, in my most recent experiments, I have been looking at an entirely different factor that seems to influence wax production: how many individual bees there are in a given volume. Since this is the first semester that I have been working on this project, I do have some preliminary data, but I have mostly been working on finalizing methods. Once I have all my methods and protocols finalized, I will be able to move on to examining how other factors, such as ambient temperature and the type of feed provided, influence wax production.
Before examining what factors affect the efficiency of wax production, it is important first to understand the physical and chemical processes by which beeswax is produced. Beeswax is produced in the wax gland complexes of a honey bee’s abdomen. The wax gland complex consists of three cell types: epithelial cells, adipocytes, and oenocytes (Cassier & Lensky 1995). These three cell types work together to produce and secrete the hydrocarbons, fatty acids, and proteins that are present in beeswax. The adipocytes and oenocytes make up what is known as the fat body, and these cells produce the wax while the epithelial cells are mainly there to provide transport tubules for transporting the wax to the surface of the abdomen to be secreted (Hepburn et al. 1991). Honey is the main ingredient of wax that is digested in the fat bodies. The complex sugars of the honey get broken down into the basic carbon, hydrogen, and oxygen and are put back together as hydrocarbons and fatty acids (Winston 1987). Pollen is also important towards effective wax production because pollen is made up of vitamins, minerals, lipids, and proteins, which are all needed for proper wax gland development, and pollen provides more necessary ingredients for wax production (Winston 1987). According to an experiment done by Goetze and Bessling (1959), a controlled colony fed sugar and pollen produced more than nine times as much wax as a controlled colony that was just fed sugar.
As mentioned before, there have been studies that show certain factors that affect wax production. For example, Hepburn et al. (1991) it was concluded that the amount of wax produced by an individual bee is significantly affected by the age of the bee. In another study done by Pratt in 2004, it was shown that wax production can be influenced by the season and whether the colony needs more wax to accommodate events such as nectar flows or heavily laying queens (Pratt 2004). Hepburn et al. (2014) claim that wax production is also influenced by temperature because the comb-building area has to be warm enough, usually between 30-37°C, in order for the bees to be able to secrete wax scales and use them to build comb. My project aims to expand on the knowledge of factors that influence wax production, which would grant a more complete understanding of how we can better provide for bees to maximize their health and productivity.
The first experiment I did this semester was focused on how having different numbers of bees in individual cage cups affects how many wax scales each bee produced on average, as well as how it affects any comb-building behavior within the cage cup. For my experimental setup, I had one cage cup with 30 bees, one with 60, one with 90, and one with 120. For the cage cups, I used 16 ounce plastic Solo® cups that were modified according to a protocol I wrote to look like figure 2. The cup with 30 bees received one 2-mL feeding tube of 1:1 sugar water, the cup with 60 bees received two, the cup with 90 bees received three, and the cup with 120 bees received four. Each day for seven days I would refill all of the feeders, count and remove any dead bees, and count and remove all the wax scales I saw in the removeable glass container underneath the cup. In order to get a better understanding of total wax production per cup, in addition to counting the wax scales produced each day, I would take note of any drawn comb I saw anywhere around the cup. I found that the bees in cups of 90 and 120, but especially the bees in the cup of 120, liked to build comb on the sugar water feeders, as seen in figure 3.
In my methods for the previous experiment, when quantifying the amount of wax produced, I only took into account the number of wax scales that fell through the bottom of the cup into the glass container. If my goal is to measure the total amount of wax produced in each cup, I need to find a method to quantify not only the wax scales, but the drawn wax as well. Once I have calculated the average weight of a single scale, I could simply weigh the pieces of drawn wax to get an estimate of how many individual wax scales were incorporated into building it. This data would be interesting because it would allow for a more complete measurement of the total wax produced per cup of bees, and it would also show the proportion of how many total wax scales produced were used for drawing wax.
Since this was just my first semester working on this project, I still have a long way to go. I have learned a lot from my past couple experiments, and my current focus is going to be on finalizing the proper method for measuring the total amount of wax produced in a cup. My next couple experiments will be looking at how the incubator temperature in which the bees are kept, along with crowding, may affect wax production. After this, I will investigate how crowding along with feeding either honey or sugar water may have an impact on wax production. Throughout my next few experiments I will also be trying to find a threshold density of the number of bees per unit volume that seems to maximize wax production. I am very much looking forward to continuing my work on this project with the vanEngelsdorp Bee Lab!
Cassier, P., & Lensky, Y. (1995). Ultrastructure of the wax gland complex and secretion of
beeswax in the worker honey bee Apis mellifera L. Apidologie, 26, 17-17.
Goetze, G., & Bessling, B. K. (1959). Die wirkung verschiedener fütterung der honigbiene auf
wachserzeugung und bautätigkeit. Z Bienenforsch, 4, 202-209.
Hepburn, H. R., Bernard, R. T. F., Davidson, B. C., Muller, W. J., Lloyd, P., Kurstjens, S. P., &
Vincent, S. L. (1991). Synthesis and secretion of beeswax in honeybees. Apidologie,
Hepburn, H. R., Pirk, C. W., & Duangphakdee, O. (2014). Honeybee nests: composition,
structure, function. Berlin, Heidelberg: Springer-Verlag.
Pratt, S. (2004). Collective control of the timing and type of comb construction by honey bees
(Apis mellifera). Apidologie, 35(2), 193-205.
Winston, M. L. (1987). The biology of the honey bee. Harvard University Press.