Bees & Beekeeping: Present & Past
Queen Introduction: Part 2, The Effect of Attendant Bees
The attendant bees accompany the queen during shipping. In this article we begin a detailed investigation of their effects during queen introduction.
From a behavioral perspective, queen introduction involves confronting queenless bees with a foreign queen. In the presence of a foreign queen, workers typically display aggressive behaviors toward her. This aggression usually culminates in a small compact ball of bees forming around the unfamiliar queen, a condition termed balling (see Figures 1 and 2). During introduction with the queen confined to a protective cage, the bees cannot ball her directly. A partial ball forms on the screen of the introduction cage, usually as a single layer of aggressive bees.
In this situation, bees frequently bite the screen wire (see Figure 3). Other bees may arch their abdomens as if stinging through the screen mesh (see Figure 4). Bees in both positions remain motionless for some time. For brevity, bees exhibiting these behaviors will be termed ballers. Should the queen be released while aggressive ballers are on the queen cage, she would probably be killed, though she may survive unharmed or be maimed (personal observations).
Although initially the bees typically display hostility towards the new queen by balling the cage, the usual scenario has the number of ballers decreasing over time. None should remain hostile when the queen is released (a condition I regard as provisional acceptance because the bees might ball the queen or cage again if they are badly disturbed). Bees displaying queen-accepting behavior walk on the screen of the cage and briefly probe between the wires (see Figure 5).
From mainly anecdotal experience, several situations are thought to decrease queen acceptance. Some of these factors include inclement weather, lack of nectar, occurrence of robbing, and introducing queens into large colonies or colonies composed largely of older bees.
Another factor thought to reduce queen acceptance is the presence of the attendant bees during the introduction period (McCutcheon, 2001). However, recommendations on removing attendant bees before queen introduction have varied in the beekeeping literature.
The first goal of the following experimental research was to ascertain if the presence of attendant bees increases the duration of balling. Persistent balling is expected to increase the likelihood of the new queen encountering hostile bees upon her release after the bees have removed enough candy from the third compartment of a standard 3-hole shipping cage (the candy release method). The second research goal was to record the number of ballers as a function of time and observe aggression patterns in the (time series) data.
To understand research results and their limitations, one needs to be familiar with the conditions of the experiments: the foraging environment, the condition of new queens, the hive design, and the procedure for counting the bees balling the cages.
The experiments took place in Eastern Virginia (approximate latitude and longitude N3758´, W7716´). During the experimental period, a nectar flow was either not apparent or occasionally the bees collected nectar and pollen from sumac (Rhus spp.) and goldenrod (Solidago spp.). Together these plants constitute only a minor floral resource in this area. These environmental conditions would be regarded as poor for queen acceptance. I chose this dearth time because during intense nectar flows, queen acceptance can increase dramatically. Such an environmental effect could mask the deleterious effects of the attendant bees by decreasing the duration of balling.
The queens for introduction were shipped from various domestic commercial producers, but only one queen source was used for a particular experiment (to reduce the variation among queens). Upon arrival, the queens were active and small (non-physogastric). They were held in a common environment at room temperature at approximately 72 F (22 C) for 5-24 hours before introduction. The queens were shipped in and were introduced in standard 3-hole Benton cages constructed of wood and covered by screen wire typically used by queen producers in the United States. One end compartment was filled with queen candy. The other two compartments held the queen and her attendant bees.
Six to eight attendant bees accompanied each queen. Given this variability, the number of attendants was adjusted only by removing attendants so only six or seven remained. (The exact number of attendants per cage depended on the cage with the minimum number that survived shipping so that all cages with attendant bees had the same number for a particular experiment.) Whatever the attendant effect, it should be detected at these numbers (other unpublished data had verified this assumption).
Some attendants typically died during the course of the experiments and no attempt was made to replace them, especially given the difficulty of seeing inside the cage during the experimental period. Since the experimental duration extended past the typical introduction period of about three days, where the queen’s release is governed by the speed of candy removal, the cork in the passageway leading to the candy was not removed.
Provided the experimental period was long enough, on the 8th to the 10th day following queen cage installation, I briefly inspected the colonies for queen cells to prevent the appearance of virgin queens. Also on these inspections, I observed the cork blocking the candy compartment. By this time, the bees could have dismantled the granular bits comprising the body of the cork. Some corks were virtually chewed apart, but the bees never removed any corks completely.
At the conclusion of the experiments, colonies that still balled the queen cages were inspected for the presence of a second queen. If second queens were found, those colonies were excluded from the data analysis. For the two main experiments, occurring over two summers, three colonies with second queens were removed from a total of 22 colonies; a couple other colonies became too weak for data collection.
I used top-bar hives to conduct the experiments. This hive design allowed opening the hive with a bare minimum of bee disturbance, a property considered necessary to count the bees balling the queen cage without interrupting their behavior. Hive vibrations cause bees displaying balling, but only mildly, to stop and walk on the cage screen, giving the false indication of bees ready to accept the queen. They would not be counted as ballers. If that miscounting occurred systematically through the experiments, the data would be badly biased, underestimating the duration of balling.
These top-bar hives contained 14 combs with a total comb area approximately equal to 10 Langstroth deep super frames (brood frames) plus five shallow super frames, both of standard U.S. dimensions. Additional construction details of ….
