Technical interventions for prevention of swarming tendencies

Swarm on tree

 

Let us now look more closely at the pros and cons of some technical solutions which we use to prevent swarming tendencies today.

Technical solutions are all interventions designed to disrupt the existing balance in the colony and cause a situation when due to energetic, thermoregulatory, quantity or other reasons the colony is not able to afford to swarm. The goal is basically to induce a state when the self-preservation instinct outweighs the reproductive instinct and swarming is thus temporarily delayed. However, once the colony recovers from the intervention, they resume preparation for swarming. Swarming is not successful only if the colony fails to establish the normal state until the reproduction period ends. In Central Europe, this happens approximately in the middle of July. After this date due to shortening length of the daylight bees no longer swarm and anti-swarming measures become redundant. Most of these are fairly dramatic interventions, based on weakening bee colonies. The most commonly used techniques are the following:

a) Queen cells The brood chamber is dismantled into individual combs, the individual combs are inspected in order to find queen cells; these are mechanically removed. The method is little effective; it is used mostly by beekeepers with a small number of hives. For farming, this method is totally unsuitable for its laboriousness and low efficiency. Bees usually create new queen cells on the very same day, so it is necessary to repeat this action duly. Despite the fact that the method bars swarming, it does not eliminate the swarming tendency, which lowers the flow activity.

b) Inserting brood combs from other colonies. This method is based on the observation that if the worker bees are busy taking care of open brood, they do not tend to swarm. By inserting the open brood combs, we temporarily employ the nursing bees, and therefore the swarming mood is not triggered. In addition, from so treated colonies we remove the combs with capped brood. Thus we prevent hatching large numbers of house bees, which could become the bees triggering swarming. This method assumes the existence of weaker colonies on the habitat into which we shall insert the capped combs from the stronger hives. The stronger colonies receive open brood combs from the weak colonies. It is a poor method for several reasons. Firstly it supposes that we breed weak colonies at the apiary, which is in itself uneconomical. The method is also very laborious and time-consuming. It assumes that colonies are divided into strong and weak ones, and we need to keep track of their current strength. The third objection is the most serious one. This method is most risky because of the potential spreading of dangerous diseases around the apiary.

c) Inserting large numbers of the foundations. A practice popular with many large-scale farming beekeepers. Some beekeepers insert even 22 foundations in each colony every year. Their number depends on the frame size too. The smaller is the frame area, the more foundations colonies may build. The bees tend to build up the foundations and thereby stabilize the brood nest. Bees busy building feel no urge to swarm. However, foundations that are not built act as a stressor for the colony and hinder the movement of the queen.

This anti-swarming measure is usually combined with other measures, for example with the formation of splits. This method can be temporarily effective, provided that there is a flow. When the flow is over, bees do not build – they do not build during flow gaps, thus they are not fully occupied with the workload. The effect is then lost and nothing prevents swarming. Inserting many foundations (especially in spring) can damage the thermal stability of the colony. Furthermore, preparing many frames with foundations is considerably laborious. The last drawback is the fact that during plentiful flows the foundations are jammed with honey, therefore the queen can not lay them. They do not contain the brood consuming royal jelly and their anti-swarming effect is lost.

d) Splits parting. It is the most promoted anti-swarming measure nowadays. It is a process when a few combs with capped brood and bees are taken from the colony. These are inserted into a separate hive or a nucleus hive. Storage combs with honey and pollen are inserted as a cover, and a queen cell is added. So simply a new colony is created. Empty drawn combs or foundations are inserted into the original colonies instead. The method is widely used in commercial beekeeping. Unfortunately, the disadvantages of this method are obvious. During the whole year beekeepers are trying to have the strongest colonies possible for high yield, but before the flow, they have to weaken the colony by the formation of splits. This is a contradiction in itself. For beekeepers, whose apiary is growing, it is not a problem. It is the best method of colonies multiplication. For the other beekeepers who strive for a stable number of colonies, it means to have one spare hive, a super or a nucleus hive for splits formation for each colony. This is very costly. The resulting splits must be later united with the maternal colonies unless wintered as a backup colony. The method assumes that before its application queens breeding must have been carried out; beekeeper must have a source of queens or queen cells. Splits formation is laborious and time-consuming. It is not only their forming, but adequate follow-up care must also be provided. It needs to be emphasized that strong splits later tend to swarm too. Many beekeepers thus ultimately check the swarming mood not only in the colonies but also in the anti-swarming splits. The positives of this method include the fact that splits formation weaken the Varroa mite population and reduce their numbers both in the original colony and its descendants.

e) Transfer of combs with capped brood from the brood nest into the honey super. The method is based on the assumption that if the combs with capped brood are transferred into the honey super, space is created in the brood nest for insertion of foundations or empty drawn combs. This enables to lay eggs and the open brood employs worker bees so that they do not have a tendency to swarm. In addition, house bees hatch from the capped combs in the honey super; these vacate cells for storing honey. The worker bees utilize the flow and are fully occupied. However, the method is laborious and little efficient. It requires that bees are swept from the transferred honeycombs, and the queen has to be searched, as she must not be transferred into the honey super. In factory farms, it can therefore only be used as a complementary method. Its effect is not permanent either. In honey super combs with brood cumulate, honey cannot be stored in there for some time. This reduces the ability of the colony to accumulate honey. Later, when after partial hatching these combs are used to store honey, they tend to be partially clogged with honey and they are not entirely reared with brood. Such combs cannot be removed from the colony during honey harvesting. This may become a fundamental problem e.g. with rape honey. Next time honey is extracted from these combs, it is likely that floral honey is crystallized and will not get extracted.

f) Creation of artificial swarms. It is a less important method in which colonies are weakened by sweeping bees off the combs. Artificial swarm is better known as one of the methods of extensive multiplication of colonies in full summer or even in late summer. It assumes sweeping bees from a larger number of colonies. Basically, an artificial swarm is created and after the young laying queen is adopted it is a good idea to strengthen it by older This method is very laborious and therefore unusable in large-scale beekeeping. Diseases may easily be spread in the apiary. It is necessary to take the artificial swarm a few kilometres away from the apiary, otherwise, the foraging bees return back to the original hive and the artificial swarm weakens so much that it loses viability. This method is in principle rather similar to the following method of getting rid of old foraging bees.

g) Method of ridding the colony of old foraging bees. This method is based on the recognition that when foraging bees are removed from the colony, swarming does not occur. There are several variants. Lower I describe the variant most commonly used nowadays with hives consisting of supers. First, it is necessary to be close to the supplementary entrances in supers for about 2 days in advance to make the foraging bees fly to entrance solely. Then a lower super with several capped brood combs without bees is placed on the removable bottom, replenished with cover combs. A ceiling film is placed on this super and the other supers are placed above (both the brood and honey supers). Supplementary entrances are opened on these supers. Bees returning from pasture to the entrance accumulate in the bottom on the brood combs. Bees flying to forage from the open loops also return to the entrance as they are used. The upper supers are thus rid of forager bees; swarming mood vanishes. Queen cells with new queen fetus are chewed by worker bees. Queen or a queen cell must be added to the bottom super. The bottom super with the forager bees remains on the site of the original hive. All the other supers which had been placed above must be taken away, provided with a bottom, and treated as a separate colony. Therefore with this method again two colonies are formed from a single one. It is a very effective method that has never disappointed us. It can be used to suppress even very advanced swarming mood. But there are no other benefits. The method can be used only during the full flight of bees. It is extremely labour intensive and its use in large-scale beekeeping farms is, therefore, a utopia. It is used only as a supplementary method. Two colonies are formed from a single one. The colony deprived of forager bees is not self-sufficient in supplying either water or nourishment and is not able to resist attacks. Until the full restoration of flying activity (which takes at least 10 days), the colony is completely unusable for exploiting the flow.

As you can see, today’s methods of swarming prevention are far from easy. The beekeeper must often perform checks to monitor whether new queen cells are formed on the lower edges of the combs. Then the beekeeper must intervene; on time and laboriously. No wonder that many fail to monitor everything and despite all the measures carried out, numerous colonies swarm anyway. Many beekeepers, therefore, a dream of breeding bees that naturally do not tend to swarm, such bees that do not require any anti-swarming actions and do not swarm anyway. Next time we’ll talk about why it is such an impossible goal.