Progress report for FNE24-102
Project Information
Create a new queen-rearing process that induces a queen honey bee to lay eggs directly into beekeeper-supplied queen cups. Test successful methods in real-world situations with volunteer beekeepers. Communicate project results through in-person and virtual talks, as well as trade magazine publications (American Bee Journal).
Problem
This project tackles the challenge of inducing a queen to lay eggs in beekeeper-provided queen cups. The beekeeper can then use those queen cups for personal use in the apiary, or commercial use in their farm operation. By avoiding many of the factors that lead to lower reproductive queens (McAffey, 2023) (Tarpy, 2023), this will allow for better quality queen production, stronger resulting colonies from those queens, and also encourage local queen rearing. Colony loss due to queen issues was the dominant cause during the summers of 2021 and 2022 for all beekeepers (Aurell et al., 2023), and the second-most common cause of winter colony loss for commercial beekeepers. With annual colony losses ranging from 40-50% (Aurell et al., 2023), better quality queens could potentially have an oversized impact on survivorship, particularly for hobby beekeepers.
In emergency situations, a honeybee colony has no choice but to raise a new queen from available resources (very young larvae) or the colony will perish. Using this impulse to rear queens has a high success rate. This process, called the Doolittle method, has been the standard practice since the 1880s.
Honey bee colonies also make new queens when they prepare to swarm – a colony-level method of reproduction. Anecdotally, beekeepers often comment that swarm queens make the best queens. However, to my knowledge raising queens based on the swarm impulse (where the queen lays an egg in a queen cup) for commercial or breeding purposes has not been seriously pursued.
Swarm-impulse queen rearing is not a straightforward task. If a beekeeper simply places a frame of empty queen cups into a colony the queen will not successfully lay in them. It is far more likely that the worker bees will create worker-sized cells on the beekeeper’s queen frame instead of queens.
It is not known exactly what induces a queen to lay in queen-sized cups as the colony prepares to swarm. The worker caste most likely controls the entire swarm process, starting with the process of making (“drawing out”) natural queen cups. After the queen lays in the cups, and prior to swarming, workers will create large queen cells (cups now occupied by a developing queen) that hang vertically in the hive (all other cells are oriented horizontally).
These queen cups can exist in a non-swarming colony as well, remaining unoccupied by a queen-destined egg or larva. This suggests that even if the queen lays an egg in a natural queen cup, workers may remove those eggs if there is no need to raise a queen. It is also possible that workers in a swarm-ready hive will corral the queen toward queen cups they have prepared for her so that she is induced to lay in them.
In order to have the queen successfully lay eggs in beekeeper-supplied queen cups, the colony must be manipulated to mimic a swarm condition where the workers will allow (or induce) the queen to lay in these cups. By offering the colony manufactured queen cups, the bees will have a template to suggest a need for swarm cells, and the beekeeper will be able to safely remove ripe queen cells. This reduces the risk of damaging the developing queens, and results in queen cells that can be safely transported between colonies or to other beekeepers.
The methodology will be crafted to bring the process of queen rearing within easier reach of all beekeepers, particularly hobbyists and small-scale producers. By removing the highest perceived (and real) barrier of grafting delicate larvae, beekeepers could raise multiple queens by using techniques they already practice in their apiaries; managing colony population, confining the queen to a restricted area of the hive, and conducting frame manipulations.
Solution
This project will test manipulations of honey bee colonies, queen cups, and queen cell frames to identify steps that will successfully convince the colony to create queens in beekeeper-offered queen cups. A successful process will enumerate steps that smaller beekeepers can use to raise queens to improve the health or genetic strain of their colonies. The ideal result will be one that large-scale breeders could adapt for their own operations in a cost-effective manner.
Once a successful method is identified, additional beekeepers will be recruited to test the methodology in their own apiaries. These beekeepers will have at least three years of overwintering success, and apiaries of varying sizes, with a desire to raise queens for personal use or sale. Additional feedback from these real-world trials will be used to further refine any successful technique.
Shelley Stuart has been beekeeping since 2009, and became a Cornell Master Beekeeper in 2017. The apiary currently has 17 full-sized colonies and three nucleus colonies. After several years of farmers' markets and online brewing kit sales, she is turning toward breeding bees on a small scale. She has used the traditional Doolittle method of queen rearing, has traditional queen rearing equipment, and with this grant endeavors to create an approachable method to raise bigger queens through the natural honey bee swarm process. If successful, the swarm queen method of rearing honey bee queens will allow beekeepers of all skill levels and sizes to successfully breed more robust queens for their apiaries, operations, and local environments. An additional focus is to perfect a method that does not require specialized equipment so that a beekeeper can easily use off-the-shelf supplies.
Cooperators
- - Technical Advisor
Research
Colonies
The experiments used colonies housed in 8 frame Langstroth hives (deep/medium) and 5 frame nuc boxes. Colonies were headed by second year (overwintered) queens with the exception of one nuc that entered the trials in June. That nuc had a first-year, swarm-raised queen.
Bees were kept restricted with regards to space; I deliberately pushed the population to overcrowding, to help trigger swarm instincts. I was prepared to mimic ample resources with pollen subs and sugar syrup (another known swarm trigger), but colonies had ample pollen and nectar coming in during May.
Queen Frames and Cups
I offered bees queen frames with only queen bars and cups, frames with partial brood comb and partial queen cups, and fully drawn brood frames with queen cups pressed into the face. (Figure 1.)
I offered the queens standard JZBZ cups, 3-D printed cups with a larger diameter than JZBZ, and wax-dipped cups pressed onto a 3-D printed base to make them easier to use on a queen bar. (Figure 2.)
Queen Control
In both full-sized hives and nucs, I confined queens in a deep frame queen isolation cage and gave her a frame with queen cups. Additionally, in one nuc colony the queen was allowed to freely roam the colony, where frames prepared with queen cups were available for her to lay.
Education & Outreach Activities and Participation Summary
Participation Summary:
A feature article will be submitted in January to the American Bee Journal. Spring updates were posted at HoneyappleHill.com/sare-grant, and cross-posted to HoneyApple Hill's Facebook page.
Learning Outcomes
Key observations, and factors that inform next year's experimental setup:
Ease of use
- The intent of any successful method is to make swarm queen rearing accessible to hobbyists (as well as more commercial queen rearers). With the original single deep method, once you push the colony to the swarming level the colony is packed with thousands of bees.
- Using this method, having additional equipment at hand to move frames from the active box to a "holding" box helps to keep a queen from wandering from an unsearched frame to one that's already inspected.
- Finding the queen in this mass can be extremely challenging and/or time consuming, particularly for a newer beekeeper.
- Manipulating the queen can be daunting and tricky to accomplish without injury to queen or stings to the beekeeper.
- Since I want to embrace the hobby-level beekeeper in the objective of raising swarm queens, finding a way for them to breed better queens without accidentally damaging their stock through inexperience is important.
- Individuals who feel uncomfortable handling a queen can benefit from using a queen clip or queen catcher at first.
- A similar problem exists when checking a swarm queen frame in an isolation cage. A laying queen with a frame of brood and swarm cells means that the frame may be covered with worker bees feeding the larvae. Pulling the frame out to check the status of the queen cells -- or to remove the queen cells -- risks the queen escaping into the main colony or flying into the grass.
- Having additional equipment at hand to move the isolation cage prior to inspecting allows the beekeeper to maintain the queen's location in a known place, so that is easy to recover her. Using the queen catcher can be helpful in this as well.
- However, depending on how long the queen has been isolated in the cage, the colony may be easing back from swarm pressures, as capped brood hatch out, making space in the main brood nest for a queen to lay in.
- In the nucleus (small) colony experiments, the queen isolation cage was prohibitively large and reduced the colony laying area too much.
- Omitting the isolation cage, and only offering experimental frames, resulted in charged queen cells.
- Increasing the size of a nucleus box is possible, but then it requires custom, not commercially-available, equipment. I would like to take advantage of mass-marketed equipment as it's readily available to any beekeeper.
Bee behavior
- As expected, simply placing a queen bar in an isolation frame (Figure 1 above, top frame) with a queen does not result in charged queen cells within 48 hours (or any short period of time).
- Worker bees have no reason to attend the queen in the cage other than to feed her. Any worker influence on queen cell production is therefore very limited, even when the colony is clearly preparing to swarm.
- The queen may respond to the lack of workers around her, and sense that there are not enough nurse bees to provision queen cells, therefore she does not lay in them.
- If left in the isolation cage long enough (approximately 3 weeks) the queen will lay eggs in the cups, which attracts workers to the isolation cage. The workers will provision queen cells, but also start to build out worker comb for the queen to lay.
- This may be because the queen can no longer not lay eggs; her biology forces her to find a place to start laying.
- Three weeks is not an ideal queen breeding cycle. While a hobbyist may afford a relaxed queen rearing timeframe, a commercial beekeeper needs queens at a more reliable and immediate pace.
- After three weeks, most capped brood in the colony has emerged and the colony is stepping back from a swarm impulse.
- Worker population will start to decrease, and there will be fewer nurse bees to provision any larvae.
- The workers are much more likely to build worker comb in the queen bars instead of encouraging queen rearing.
- After testings the various frame configurations, the most successful one appears to be a frame where the top 3/4 has drawn worker comb, with a single row of queen cups offered at the base of this comb. (Figure 1 above, middle frame)
- This more closely mimics natural swarm cell conditions.
- Based on the other frame configurations, having open worker brood near the offered queen cups makes a difference in the acceptance of the queen cups, and seems to have a strong influence on the queen laying in those cups. This more clearly shows in a 1/3 brood, 2 queen bar frames. The queen cups nearest to the brood comb received the most attention from worker bees.
- When using a nucleus colony, it was not necessary to add the queen isolation cage for a successful outcome.
- The small volume meant that the queen cups were regularly exposed to the workers and the queen. The colony could experience a natural, bee-driven, swarm cycle while at the same time provisioning beekeeper-suppled queen cups, which could then be harvested by the beekeeper.
- Adding multiple experimental frames did not appear to improve outcomes (number of charged queen cells): in a situation with three experimental frames and two brood/honey frames, the number of charged cells at swarming time did not meet the capacity of the queen cups offered.
- Bees can (and will) "uncharge" queen cups, meaning that they will remove queen larvae for undetermined reasons. Regardless of why bees remove queen larvae, the swarm queen breeder must be ready with a cell finisher colony.
- Removing the experimental frame in full would reduce swarm pressure on the breeding colony.
- This keeps the selected breeder queen in your apiary.
- It can slow down the queen rearing process.
- Removing only the queen cups may allow the breeder to generate more queen cells.
- This risks the swarm pressure in the nuc building up too much and the nuc swarming.
- It allows for a more rapid queen breeding cycle.
- Removing the experimental frame in full would reduce swarm pressure on the breeding colony.
Testing objectives for 2025
- Use only nucleus-sized colonies to create swarm queens may be the ideal method, rather than a full-sized colony.
- The bees will push to the swarm status quicker.
- Fewer bees (by 50%) makes it easier to handle/manipulate the colony in general.
- In 2025, offer only one experimental frame per nuc to see if more queen cups are successfully charged.
- Test offering five experimental frames per nuc to see if consistency in the brood nest layout has an impact on the number of cups charged.
Current implications for hobby and commercial queen rearing
Based on the results of 2024's season, the viability of using swarm queen rearing as a direct commercial queen rearing process may not be reasonable. Commercial queen rearers need hundreds of queens available on a known timetable. My initial trials have not convinced me this is possible when trying to work with the natural cycle and impulses of the honey bee.
Indirectly, a commercial breeder may benefit by using the F1 generation of bees originating from the swarm queen. Research has shown that larger queens will create larger workers; by using the larger daughter worker larvae in their commercial grafting, commercial breeders may find their grafted queens are also larger. This could allow queen breeders to "reset" the size of their breeding stock while maintaining a commercial-level production volume. This "reset" could happen with one generation of swarm queen, or you can allow a swarm queen to raise additional swarm queens before selecting graft stock. Theoretically the second generation swarm queen will be larger on average than the first generation swarm queen, which is herself larger on average than a graft-raised queen. Either way, once your swarm queen starts laying, you can then move to mass-production methods with the larvae she generates for you.
Hobbyists generally need fewer queens for their operations. This project still has the potential for greatly benefitting that cohort of beekeeper. Not only does it omit the delicate, commercial-based grafting process, it allows the hobbyist to improve their own bees, embark on a local breeding program for their own purposes (for example, creating larger mite-resistant bees), and to improve the quality of bees in their local areas through queen swaps frequently found in bee club activities.