Double Hives

I work with 12-frame divisible Dadant double hives following the method of the first president of ANERCEA, Charles Goetz, with a central division board. In winter, the double hives are arranged on three supers, which allows the colonies to warm one another. In spring, I remove the empty lower super; the central division board then splits the winter brood nest into two parts. I then swap the two remaining supers (see diagram 1). The space between the two brood zones is quickly laid up, which accelerates colony development. When one colony is strong and its neighbour average, it is sufficient to swap their positions to balance the colony strength, while the foragers remain on the same side. In summer, in migratory beekeeping, I place a queen excluder above the second super and add two to three common supers without a central division board for honey storage. The queen is confined to a reduced space, which limits the brood and increases the number of foragers, who are less occupied with brood rearing. In summary, management with divisible hives allows for much more precise colony management, but it requires more time.

My stock consists of:

• 50 production double hives (Carnica F1 with one- or two-year-old queens),
• 3 queen-rearing double hives (starter/finisher),
• 12 hives with pure, selected Carnica queens.

The Queen-Rearing Colonies

 

For queen rearing, I use double hives containing a queenless compartment (see diagram 2). They are constructed as follows: two supers of 12 frames each are placed on a hive floor, separated by a central division board that is completely bee-tight on the sides and against the floor. Between the first and second super there are two half queen excluders, forming four compartments of six super frames each.

The queen is confined in one of the two lower compartments; the other half of the hive is queenless, with the starter section at the top. On the queenless side, a queen excluder prevents a queen returning from her mating flight, attracted by the queenless colony, from entering, which would compromise the acceptance of the queen cells. A third super is placed on top for food storage. Frame rotation is carried out each week according to the following scheme: right side (with queen) — the larval frames without the queen from the first super are moved up into the second super; right side — the brood frames from the second super are moved across to the left side of that same super; left side (queenless) — the sealed brood frames from the second super are moved down into the first super; left side — the empty frames from the first super replace those of the first super on the right side. In this way, the queen always has space to lay, and the queenless compartment always contains emerging brood. These manipulations are carried out with the bees on the frames, which are sprayed with lactic acid to limit the proliferation of the varroa mite. No new queen cells are initiated: on the finisher side, the queen's pheromone prevents this, and on the starter side, the larvae are too old.

The grafting frame for Dadant supers consists of two pairs of metal rods salvaged from old queen excluders (see photo 2). On two bars of a grafting frame I fix 38 cell cups. I trim the edges of the cell cup holders to reduce their width (see photo 3), which decreases the spacing between two cups and more closely resembles natural brood. The cell cup holders bear distinctive markings (1, 2, 3 holes, etc. – see photo 3), making it possible to form series. I record the series, the grafting date, and the breeder queen: in this way, the simple cell cup holder provides all the useful information with minimal record-keeping.

Queen Rearing

The maternal lines consist of breeder queens aged at least two years, of the Carnica race, mated at a mating station and selected over one production season and two winters. From the third year onwards, the parent colonies are maintained as nucleus colonies so as not to exhaust the queens. Larva grafting is carried out using a Chinese grafting tool. The grafting frame is introduced into the second super, left queenless side (starter). A small amount of fondant is placed on the cells to promote larva acceptance. After 24 hours, the frame is moved to the right side, above the queen (finisher). The cells remain in the finisher for only five days, with very little wax construction between them. Five days later, when the cells are sealed, they are transferred to a Swienty incubator hive modified by the addition of metal wires forming channels, to prevent the domino effect in the event of a hair curler falling (see photo 4).

A falling cell can be fatal to it. The capacity of the incubator hive has been increased and handling safety improved. It sometimes happens that a queen emerges as early as day 11; without a small amount of fondant placed at the bottom of the hair curler, she would survive only a few hours. On day 11, the cells are introduced into Apidea nucleus colonies. A check for egg laying is carried out ten days later. Queens are dispatched by priority mail from day 20 onwards. In Switzerland, a letter submitted at the counter before 18:00 is delivered the following morning. Delays are rare and generally due to a dispatch error. It is important to hand in shipments at the counter so that they are sorted manually. Each queen is accompanied by an introduction notice.

Photo 5 shows an Apidea nucleus colony in winter configuration, with one super and a feeder (10 frames in total). This configuration makes it possible to overwinter certain queens and to divide the nucleus colonies in spring in order to rebuild the entire stock.

Stock Renewal

Formation of nucleus colonies in spring: In order to rejuvenate the stock, all colonies that are neither going on summer migration nor dedicated to queen rearing are converted into nucleus colonies during the month of May. These consist of three Dadant super frames and a cage containing a laying queen without attendant bees. The colony is then expanded and fed between May and mid-July. If the queen proves satisfactory (her quality can be assessed after approximately two months), this nucleus colony, then on six super frames, is united with a queenless production colony. A sheet of newspaper between the two colonies allows for a gentle merger. The advantage of spring nucleus colonies is that low-quality colonies do not need to be overwintered. Furthermore, it is possible that May queens are of better quality than those produced at other times, as they follow the natural biological calendar of the bee.

Formation of nucleus colonies in summer: In mid-July, the supers are removed, the colonies fed, and treatment carried out against the varroa mite. Waiting for an August honey flow would carry a significant risk, as the varroa mite multiplies very rapidly at that time and weakens the winter bees. The bees in the supers are surplus and perish quickly. I use them to form artificial swarms. Instead of installing a clearer board and removing the supers, I brush 1.8 kg of these bees into a hive containing ten sheets of foundation (or five brood frames). As the bees are quickly confined, the intervention at the apiary remains calm. It then suffices to treat against the varroa mite (35 ml of 3.5% oxalic acid by trickling method), to feed, and to introduce a queen, whose acceptance rate reaches 99.9%. One month later, after the addition of two further frames and sufficient feeding, the nucleus colonies are ready for overwintering with a low varroa infestation. These colonies serve to offset winter losses or are sold.

 

See also:

• How to introduce queens?
• Creating nucleus colonies and queen rearing
• Practical Guide: 1.3.2. Trickling method