Beekeeping: Part 3

Communication in Bees

Bees communicate with one another in a number of ways such as drumming feet, flapping wings like a ‘dance’ and use of pheromones. The dance performed by the scout bees is one way the bees inform each other of the location of food and how far away it is. There are several types of dances performed by the bees, but the main ones are the round dance and the waggle dance. The round dance is performed by bees that forage less than approximately 100 metres from the hive. Waggle dance is performed to locate food source beyond 100 metres from the hive. Other dances include the vibrational dances which are done mostly by pollen foragers, and the transition dances. Vibration is used on the queen to inhibit her activity, prevent her from destroying developing queen cells, slow egg production, and to exercise her. The scout bees also perform a characteristic dance to locate the new found home to which bees intend to swarm.

The queen releases a substance called a pheromone (sometimes called queen substance) which serves different functions. The pheromone enables her to identify members of the colony, to inhibit ovary development in worker bees, to prevent the workers from building queen cells, to help a swarm or colony to move as a cohesive unit, and to attract drones during mating flights. The absence of the queen substance (e.g. when the queen dies) produces opposite responses, i.e. worker bees begin to develop ovaries and to build queen cells, and a swarm searching for accommodation will not cluster but will divide into smaller groups that cannot support the normal life of a bee colony. Colony decisions are taken by the collective behaviour of bees within one colony sharing the same odour, allowing guard bees to detect intruders. The workers who pick up the pheromones to send signals to others know how to detect the age of the queen by the strength of the pheromones she produces. When the queen gets old, the workers start feeding royal jelly to some broods which now starts forming another queens. The cells in which they are found start forming a cup shape. When a new queen is formed, she experiences swarming with most members of the colony. Artificial swarming is necessary after 3-4 years of harvesting honey in order to split your colony.

Mating only takes place during nuptial flight, which is only possible when the newly emerged queen decides to swarm.

Pheromones

Pheromones are “external hormones”—chemicals secreted by one insect that affect another of the same species; it is considered to transfer information. These chemicals are released from the exocrine glands and are more important for the sensing in insects than the visuals and acoustics. In honey bees, 18 (up to 36) compounds or mixtures of compounds act as pheromones. All the known chemicals are ‘releaser’ pheromones that release or elicit a specific behavior. ‘Primer’ pheromones control basic activities, for instance, the queen’s pheromones which affect the worker bees egg laying, queen production and foraging behavior.

Workers: Nasonov (for orientation); footprint pheromone; forage marking pheromone (ethyl oleate) — slows maturity of nursing bees; sting-produced alarm pheromone (Z-11 or isoamyl acetate) – attracts bees to previously stung spot; mandibular produced pheromone (2-heptanone) – repels robbers from the hive; egg marking pheromone – helps the nurses bees differentiate between eggs laid by the queen and those of the workers.

Queen produced pheromones

The queen mandibular pheromone (QMP): these are important sets of pheromones in the bee hives which affects social behaviours, maintenance of the hive, swarming, mating behavior, and inhibition of ovary development in worker bees. They include: (E) 9-oxodec-2-enoic acid (9-ODA) which is “queen substance” inhibits queen rearing as well as ovarian development in worker bees; strong sexual attractant for drones when in nuptial flight and critical to workers recognition of the presence of the queen in the hive; the (R, E) 9-hydroxy-2-enoic acid (9-HDA) which promotes stability of a swarm or a calming influence; (S, E)-(+)-9-HAD; Methylparaben (HOB); 4-Hydroxy-3-methoxy phenylethanol (HVA)

Queen retinue pheromone: these are responsible for the retinue attraction of worker bees around their queen. They include: Methyl oleate; Coniferyl alcohol; Cetyl alcohol; a-linolenic acid.

Drone pheromone: Attracts queen to mating sites and other drones to organize drone congregation areas (DCA) as a site suitable for mating with virgin queens.

Brood recognition pheromone: Emitted by both larvae and pupae and prevents workers from bearing offspring in a colony that still has developing young, stimulate workers to forage, inhibit worker ovary development, and help worker bees distinguish between worker larvae and drone larvae and pupae.

Orientation Flight

On warm days, especially after several days of rain, one often sees bees flying in ever increasing circles round the hive. These are not foragers but young bees carrying out a reconnaissance of their hive and its position. This exercise is called 'orientation'. The house bees are responsible for taking the young bees on orientation flight.

Swarming

This refers to the flying away of a part of the bee colonies to establish a new hive. This is a way of reproducing a new colony in nature. Queen cups are year round foundation for queen cells. Swarming is preceded by:

 Construction of queen cups

 Forcing the queen to lay eggs in these cups (more than 20)

 Colonies seal an average of 15 to 25 queen cells to ensure the parent colony gets re-queened

 Development of the queen cells

 Scout bees may go looking for new sites and workers may become quiescent immediately before swarming.

 Workers engorge their crop with honey (about 36mg as against the normal 10mg in non-swarming colonies) 10 days prior to swarming.

Factors that stimulates swarming

Distal cues for swarming include: time of year; day length; nectar availability (good); and warm weather. Proximal cues that initiate swarm include

 When the hive is small

 Overpopulation

 Worker age distribution (lots of young bees)

 Reduced distribution of pheromones (9ODA - 9-oxodecenoic acid). Each worker needs to receive appropriately 0.1micro gram of 9ODA per day to be inhibited from producing queen cells.

 When the queen is old and lays fewer eggs

 When the hive is located in the sun (causing the hive to overheat)

The swarm

 On day of swarm workers begin running in waves across combs, exciting each other. Queen is chased and bitten. Suddenly a wave rushes out the entrance, taking the queen with them. A “false swarm” may issue and return if the queen is not with them.

 Queen flies off with up to 60% of workers (10-15,000 workers)—prime swarm. They cluster, and QMP helps orient workers to the site. Scouts look for permanent site, and swarm relocates. Scouts recruit the cluster with waggle dances; there may be competing dances going on simultaneously. Scouts “steer” the airborne swarm by performing “streaking” flights through swarm in direction of new nest.

 Younger workers are more prone to go with a swarm. Up to 70% of workers < 10 days old will join the swarm. This is important for the swarm to have a supply of long-lived bees until the first brood emerges 21 days later.

 For a few days the colony is queenless, but workers emerge so population rebounds a bit by the time first daughter emerges.

 Back at parent colony depending on population size, workers either let new daughter kill her rivals in their cells, or guard them (workers imprison new queens in their cells and don’t let them emerge). Queens exchange audible signals called “piping” or “quacking.” Not sure of the function of these signals.

 Brood mortality is high during this phase.

 If a secondary swarm (or after-swarm), workers shake new daughter queen to keep her agitated, then she flies off with the swarm

 Process repeated until colony is too weak to be split any more.

 Workers let last daughter kill rivals

 Colonies spend rest of season rebuilding strength and storing food for winter.

Factors limiting swarming

 Presence of ample space in the hive

 When the queen is young.

 Taking out brood or artificial swarm

 When the hive is placed in a shade

 When young bees are supplied with comb foundation damage caused by swarming

 Losing the bee population

 Loosing honey production.

Adverse Natural Factors and Pests

These problems are grouped into three categories: Natural climatic conditions, man and his activities, and natural pests.

Natural Conditions

Problems are also encountered by the honeybee in the dense equatorial forest:

 Some trees are so tall that worker bees will not visit them for any reason.

 Tall trees in the equatorial forest have few or no flowers, so that nectar and pollen are scarce.

 The sun’s rays cannot reach the forest floor, the thick undergrowth prevents the free flow of air and the temperatures are too low to induce worker bees to fly out to procure the commodities essential for the colony.

 High humidity levels promote serious fungal diseases in the insect.

 High moisture content in the nectar prevents honey from curing well.

 Ants, reptiles, birds and other hive predators are present in the forest in large numbers.

Human Activities

The honey-hunter, bush-burning, bee-burning, the palm-wine tapper, poisoning bees – chemicals and pesticides sprayed on the farm.

Insecticides and pesticides

Pesticides poison bees. A colony can die within 3 hours of exposure to insecticides as they quickly pass it in the nectar to other bees and brood in the hive. A bee spinning on the ground outside the hive is a sign of insecticide poisoning. Also bees often die with their tongues sticking out. Keep in touch with other farmers and know when they are spraying. Ask them to spray at night when the bees are not flying. When spraying is taking place close your colonies using mesh wire to allow ventilation. Never totally block up the holes or the bees may die of suffocation. Feed the bees with sugar syrup whilst they are enclosed.

Bee Pests, Predators And Diseases

A number of bee pests, predators and diseases occur and affect to a significant degree the health and productivity of bee colonies.

Bee pests and predators: They include: Wax moth, Ants including safari ants, Honey badgers, Hawk moths, Man, Cattle, Baboons, Termites, Hive beetles, Birds, Wasps and hornets, the bee pirate (wasp-like insect), Louse, the praying mantis, Spiders, Toads, Snake, Lizards, Mice, Robber bees, Pesticides, Mould and fungus, Acarine (tracheal) Mite, Varroa Mite, Tropaelaelaps, Mite, Cleptoparasitic drone flies (flies that look like bees).

Bee Diseases: Diseases that affect bees include: American Foul Brood, European Foul Brood, Sacbrood, Nosema, Chalkbrood, Chilled brood, Black Queen Virus (BQV) disease, Amoeba and Paralysis.

Bee/Honey Harvesting Equipments

 Smokers: This is modern equipment used for applying smoke to the hive when harvesting honey. Other materials for smoking include: Semi dry grass, Wood shaving, Coffee husks, Maize comb, Bean husks, Millet husks, Dry cactus, Dry pawpaw stem, etc.

A SMOKER

 Bee suit: Consists of an overall and a head veil; the overall is made of white or yellow khaki material with a head veil attached to it. The net of the head veil is made out of strong black nylon material in order to have good vision and ventilation. The hat of the veil consists of the same khaki material of the overall with a round stretching stiff ring of approximate diameter of 42 cm. The veil is attached to the overall with a double zip and can be detached. The overall should cover whole body right from the legs, arms up to the neck with a long jacket zipper from the fry up to the neck. The overall should be fitting loosely (not tight) with provision of pockets; at least 4 pockets - 2 at the chest and 2 around the thighs.

BEE SUITE

 Bee gloves

 Gumboots

 Hive tool set: This consist of bee brush, hive opener and stainless steel knife

 Air-tight buckets

 Food grade drums

 Weighing scale

 Refractometer: It is a machine used to determine the percentage of moisture in honey.

A REFRACTOMETER