Swarming (honey bee)

Swarming is the natural means of reproduction of honey bee colonies (considering the colony as the organism rather than individual bees which cannot survive alone), including the domesticated Western honey bee. In the process two or more colonies are created in place of the original single colony. It is considered good practice in beekeeping to reduce swarming as much as possible by several techniques, as allowing this form of reproduction often results in the loss of the more vigorous division, and the remaining colony being so depleted that it is unproductive for the season. Beekeepers control reproduction by making nucs (nucleus or starter colonies) or by shaking package bees (usually for sale) from hives in the spring prior to the natural swarm time.

New honey bee colonies are formed when queen bees leave the colony with a large group of worker bees, a process called swarming. The first or "prime swarm" generally goes with the old queen. As soon as the swarm is established as a new colony, the bees raise a new queen, or sometimes a replacement virgin queen is already present in the swarm. "Afterswarms" are usually smaller and are accompanied by one or more virgin queens. Sometimes a beehive will swarm in succession until it is almost totally depleted of workers.

Swarming is mainly a spring phenomenon, usually within a two- or three-week period, the usual period depending on the locale. But occasional swarms can happen throughout the producing season. Old fashioned laissez-faire beekeeping depended upon the capture of swarms to replenish beekeeper colonies and early swarms were especially valued. An old English ditty says::A swarm of bees in May is worth a load of hay;:A swarm of bees in June is worth a silver spoon;:A swarm of bees in July isn't worth a fly.

Swarms of bees sometimes frighten people, though they are usually not aggressive at this stage of their life cycle. This is principally due to the swarming bees' lack of a hive to defend and are more interested in finding a new nesting point for their queen. This does not mean that bee swarms will not attack if they perceive a threat; however, most bees only attack in response to intrusions against their hive. Most swarms will move on and find a suitable nesting location in a day or two. Beekeepers are sometimes called to capture swarms that are cast by feral honey bees or from the hives of inattentive beekeepers.

warm management

During the first year of a queen's life the colony has little incentive to swarm, unless the hive is very crowded. During her second spring, however, she seems to be programmed to swarm. Without beekeeper "swarm management" in the second year, the hive will cast a "prime swarm" and one to five "after swarms." The old queen will go with the prime swarm, and other swarms will be accompanied by virgin queens.

Swarming is to the beekeeper what losing all of his calves is to a cattleman. The hive that cast the swarm is often so badly depleted that it will be unproductive for the entire season. For this reason, beekeepers try to anticipate swarming and assist the bees to reproduce in a more controlled fashion by "splitting hives" or making "nucs." This saves the "calves" and keeps the "cow" in condition to accomplish some work.

Beekeepers that do not wish to increase the number of hives they have may use one or more of the many methods for swarm control. Most methods simulate swarming to extinguish the swarming drive.

warm control methods

* Clipping one wing of the queen.When one wing of the queen is clipped, a swarm may issue but due to the queen's inability to fly, the swarm will gather right outside the original hive, where the swarm can be easily collected. Even though this is not a swarm prevention method it is a method of swarm retrieval.
* In the "Demaree method" a frame of capped brood is removed with the old queen. This frame is put in a hive box with empty drawn frames and foundation at the same location of the old hive. A honey super is added to the top of this hive topped by a crown board. The remaining hive box sans queen is inspected for queen cells. All queen cells are destroyed. This hive box, which has most of the bees, is put on top of the crown board. Foraging bees will return to the lower box depleting the population of the upper box. After a week to ten days both parts are inspected again and any subsequent queen cells destroyed. After another period of separation the swarming drive is extinguished and the hives can be re-combined.

* Simply "keep the brood nest open". In preparation for swarming, bees fill the brood nest with honey. The queen stops laying to be trim enough to fly, and her newly unemployed nurse bees go with her. The concept of this method is to open the brood nest to employ those nurse bees and get the queen laying again and redirect this sequence of events. This is done by any number of slight variations from empty frames in the brood nest, frames of bare foundation in the brood nest or drawn combs in the brood nest, or moving brood combs to the box above to cause more expansion of the brood nest.

* "Checkerboarding". In the late winter, frames are rearranged above the growing brood nest. The frames above the brood nest are alternated between full honey frames and empty drawn out frames or even foundationless frames. It is believed that only colonies that perceive to have enough reserves will attempt to swarm. Checkerboarding frames above the brood nest apparently destroys this sense of having reserves.

warming location

When honey bees swarm from the hive they do not fly far at first. They may gather in a tree or on a branch only a few meters from the hive. There, they cluster about the queen and send scout bees out to find a final location. From this first rest stop, a swarm may fly for a kilometer or more to the scouted out location.

Swarming creates a vulnerable time in the life of honey bees. Cast swarms are provisioned only with the nectar or honey they carry in their stomachs. A swarm will starve if it does not quickly find a home and more nectar stores . This happens most often with early swarms that are cast on a warm day that is followed by cold or rainy weather in spring. The remnant colony after having cast one or more swarms is usually well provisioned with food, but the new queen can be lost or eaten by predators during her mating flight, or poor weather can prevent her mating flight. In this case the hive has no further young brood to raise additional queens, and it will not survive. Good beekeepers who are aware that a colony has swarmed will usually add brood with eggs, so that the bees have additional young bees to care for the queen and a second chance to raise a new queen if the first one fails.

Africanized bees are notable for their propensity to swarm. Being tropical bees, they tend to swarm any time incoming food is scarce, thus making themselves vulnerable in colder locales. Mainly for this reason, they tend to not survive in higher latitudes.

warm capture

There are various methods to capture a swarm. When the swarm first forms a cluster it is relatively easy to capture the swarm in a suitable box or nuc. There are also swarm traps with Nasonov pheromone lures that can be used to attract swarms. One method that can be employed when the swarm is located on a lower branch or small tree is to put an old white bed sheet under the swarm location. A nuc box is put on the bed sheet. The swarm is sprayed from the outside with a sugar solution and then vigurously shaken off the branch preferrably during full sun light. The main cluster, hopefully including the queen, will fall onto the white bed sheet and the bees will quickly go for the first dark space in sight, which is the opening of the nuc. A organized march toward the opening will ensue and after 15 minutes the majority of bees will be inside the nuc. This capture method does not work at night though.

External links

For more information on the bio-chemical factors that govern swarming, see [http://www.beedata.com/apis-uk/newsletters/apis-uk0703.htm apis newsletter July 2003] .
* [http://www.bushfarms.com/beesswarmcontrol.htm Swarm Prevention - Bush Bees] .
* [http://maarec.cas.psu.edu/pdfs/Swarm_Prev_Control_PM.pdf Swarm Prevention - MAAREC] .
* [http://web.aanet.com.au/~Bees/swarm.html Help with bee swarms in Australia] .