The Honeybees are truly the gardener's friend and are not the killer beast depicted in the cinema. If not for them and the other species of bees, plant life would be reduced to mainly wind-pollinated grasses and trees, as they pollinate most of the flowering plants. They have been doing this for millions of years, ever since the angiosperm plants appeared and needed a vector to transfer pollen. Their value to food production is priceless as they pollinate so many of the crops grown worldwide.
The native bee Apis mellifera mellifera is one of many species of bee which belong to the insect order Hymenoptera. They have been associated with humans for a long time and cave paintings depict the harvesting of honey 8,000 years ago. Later civilizations domesticated them by providing artificial hives, and breeding has produced the docile Western Honeybee now kept for honey production. This honey was the main sweetener of food until sugar was introduced, also the wax by-product provided the candles for illumination.
Unlike most insects, honeybees remain active throughout the winter so they use the nectar from flowers to produce honey which provides plenty of food when it is unavailable from plants.
One of their less favourable atributes is their sting, a modified ovipositor (egg-laying tube), combined with a venom gland to create a stinger at the end of the abdomen. Because the stinger is modified from a structure found only in females, male bees cannot sting. When threatened, honeybees will swarm out and attack with their stingers to drive the threat away, but generally as they forage around they are quite harmless and only sting if accidently caught in clothing.
Sometimes bees can become a nuisance to neighbours, especially in urban areas. They may be foraging for food or water - a pond can be an attraction, so it is important to have a source of water close to the hive. The Italian Bee Apis mellifera lingustica is said to be a gentler sub-species and may be more suited to these situations, although it is less productive. Bees may also become aggressive if approached with a lawnmower or other noisy equipment.
Bad tempered strains of bees can arise from the crossing of incompatible sub-species. This occurred with A. mellifera scutellata, the Africanized Honeybee, a subspecies imported to Brazil from South Africa to cope with tropical conditions. After escaping to the wild it has spread across South and Central America. It is very aggressive and a number of deaths have resulted from mass stinging leading to the term 'killer bees' which has been exploited by Hollywood. The aggressive behaviour evolved in their native Africa where they are predated by Honey Badgers which excavate their nests for the honey and larvae.
Honeybees are social insects and create elaborate nests, or hives, containing up to 20,000 individuals during the summer months. (Domestic hives may have over 80,000 bees.) Working together in a highly structured social order, each bee belongs to one of three specialized groups called castes - queens, drones and workers.
There is one queen in a hive and her main purpose in life is to make more bees. Until the seventeenth century the queen was thought to be male and was called the 'King Bee' as it was believed that the largest bee had to be male, closer examination showed that the 'King' had only female parts. The workers feed a few selected larvae a special food called "royal jelly" which causes them to become queens. When active she can lay over 1,500 eggs per day and will live for two to eight years. She is larger (up to 20mm) and has a longer abdomen than the workers or drones, which she controls by emitting chemical signals called "pheromones". She has chewing mouthparts and her stinger which is curved with no barbs on it, can be used many times.
The drones are male and have no stinger. They live about eight weeks and only a few hundred are ever present in the hive with the sole function of mating with the queen, if one is produced in a given year. They are bigger than the workers and have bigger eyes than the other castes. At the end of the season they are considered non-essential and are driven out of the hive to die. They also die after mating as their whole blood supply us needed for the effort.
Worker bees are all sterile females making up the vast majority of the colony and do all the different tasks needed to maintain and operate the hive. Young workers are called house bees which work in the hive doing comb construction, brood rearing, tending the queen and drones, cleaning, temperature regulation (by beating their wings) and defending the hive. Older workers are called field bees foraging outside the hive to gather nectar, pollen, water and certain sticky plant resins used in hive construction. Workers born early in the season will live about 6 weeks while those born in the autumn will live until the following spring. Workers are about 12 mm long and highly specialized for what they do, with a structure called a pollen basket (or corbiculum) on each hind leg, an extra stomach for storing and transporting nectar or honey and four pairs of special glands that secrete beeswax on the underside of their abdomen. They have a straight, barbed stinger which can only be used once. It rips out of their abdomen after use and continues to pump venom; this kills the bee.
In the event of being stung, scrape the bee off with a finger-nail or blade; do not pull as gripping the bee or the remaining sting will inject more venom. The venom is acid in nature so it can be neutralised by applying an alkaline solution such as Sodium Bicarbonate.
Bees have a very keen sense of smell to guide them to sources of food. This is being exploited to use them to 'sniff out' certain substances, eg. explosives. The bees are trained by rewarding them with sugar solution when they react to the chosen substance - they stick out their tongue. This training can be in a matter of hours so is much easier than with a dog. When they are trained they can be used to find land mines as on release they congregate around the hidden bomb hoping for their usual reward, without any danger of activating any sensitive mechanisms. They can be installed in a small container which uses a laser beam focused on the tongue that triggers an alarm when broken, so making an effective bomb detector.
The worker bees scout for accommodation and if they find a suitable site, relay the message to the queen when they return to the hive. This can lead to a swarm which moves to the new site which could be in any hollow space. This happened to me a few years ago when a swarm moved into a wall which has an outer skin, unfortunately as it is south facing the space becomes quite hot in summer and they moved on a few days later, so I didn't get any honey. If a colony of bees arrives in your garden there is no need to panic. You should contact a member of your local beekeepers' association and they will advise on the action to take. The easiest way to find them is online, eg. the Ulster Beekeepers Association.
The honeycomb, which is formed at the centre of the hive, consists of flat vertical panels of six-sided cells made of beeswax; it is produced from glands on the underside of the abdomens of young workers between 12 and 15 days old. House bees take the beeswax and form it with their mouths into the honeycomb. The cells within the comb will be used to raise young and to store honey and pollen. The comb is two-sided, with cells on both sides. The nursery area of the hive is called the brood comb, and that is where the queen lays her eggs.
As well as flower nectar, pollen is a food source for the bees. Both are gathered by the field bees as they forage for food. Pollen sticks to the fuzzy hairs which cover their bodies. These hairs acquire an electrostatic charge from the motion of the fast-beating wings which attracts the pollen. Some of this pollen rubs off on the next flower they visit, cross-fertilizing it which results in better fruit production. The pollen provides protein and other essential nutrients for the bees.
Native plants are preferred by the bees to provide nectar. Hawthorn, White Clover, Heather and Blackberry are some of the better providers and Dandelions are in bloom early in the year when the bees are becoming active. Cotoneaster horizontalis is a popular garden shrub for the bees.
Bees have had to adapt to the many changes to the flora of the British Isles as agricultural practices have changed. The introduction of improved pasture which relies on nitrogenous fertilizer with the elimination of white clover is one major loss of a nectar source. Another is the close trimming or complete removal of hawthorn hedges which are said to produce the best honey.
Recently the spread of the Varroa mite among the bee population has threatened their future. It was originally a sucking parasite in Asia, but it arrived in Britain after WW2 and is in North America. As well as debilitating the bees by sucking their blood, the mites also carry various infections. Only Australia is free of the Varroa mite and there is an export market supplying bees to replace the many colonies which have been lost in recent years.
A proven method of treatment to rid a colony of the mite is by using acaricide chemicals such as Bayvarol and Apistan, but some mites have developed a resistance to these products. An older remedy is 50mls of a 3% solution of Oxalic acid in syrup fed to the bees and this makes the mites detach. Other beekeepers sprinkle some icing sugar on the bees and this encourages them to preen themselves, hopefully knocking off the mites in the process. There are Organic-approved powders available which are impregnated with small quantities of thymol which can be placed inside the entrance of the hive where it gets onto their bodies and they carry it inside. The thymol and the grooming that the powder encourages, cause the mites to be dislodged.
A recent claim is that Fleabane,Pulicaria dysenterica can be used to deter the Varroa Mite. In the mediaeval era the dried leaves were burnt to rid a house of fleas and the bruised leaves which have a soapy smell, were applied as an insect repellent - the higher levels of Thymol could be active ingredient producing this effect. In Crete where it is known by its alternative scientific name Inula dysenterica this method has been tried with an extract from the plant. The extract has been used there for many years to treat chicken mites.
It may be possible to breed a resistant strain of bee, as other species such as Apis cerana have developed a defence against the mite and another species attacks the mite, biting it in half. In a colony some of the workers keep the hive clean by removing dead larvae and some strains are better at this than others. It is hoped that selective breeding can produce a more hygienic strain and this should help reduce further deaths due to the spread of diseases which can kill off a colony.
One of these infections is American Foulbrood (AFB), a bacteria which infects the larvae causing them to turn dark brown and die. The bacteria produce persistent spores so there is no cure for an infected colony and it has to be destroyed. A treatment with an antibiotic (Terramycin) in spring and autumn should prevent infection.
The most recent cause of death to a hive is colony collapse disorder (CCD) which has been found throughout North America where a quarter of the bee population has disappeared, and in parts of Europe. Most of the bees leave the hive within the course of a week never to return, and any which remain are overcome by viruses and fungal infections. There is no full explanation for this die-off which threatens the agricultural industry as it has occured in commercial colonies which are used to pollinate crops. It would appear that those kept under organic methods and by individual bee-keepers have not been affected as badly. It is thought that neonicotinoid* insecticides used to prevent Varroa mite and to treat aphid attacks on crops, may be causing the problem as well as the factory conditions the bees are kept under. Other possibilities put forward are that the commercial colonies are transported over great distances causing stress, and the large monoculture crops they are used to pollinate may not be providing the correct diet.
A report from the Australian Pesticides & Veterinary Medicines Authority shows that the numbers of honeybees have not declined since the introduction of the neonicotinoids in 1990. In spring 2013 the EU has placed restrictions on the use of some named neonicotinoids, including Imidacloprid, for two years.
Recent research at Royal Holloway University of London has found that two diseases of domestic bees are spreading to the wild bees. The the single-cell parasite Nosema ceranae and the deformed wing virus are affecting wild bumblebees in England, Scotland and Wales, so are another factor to their decline in numbers.
*The Neonicotinoid insecticides have been implicated as possible causes of the reduction in the numbers of honeybees, their cousins the bumblebees and other pollinating insects. The numbers had begun to decrease before the introduction of these chemicals so the tendency towards monocultures in agriculture has also been suggested. Even if a crop provides pollen and nectar there will be none when it matures. As many weeds and hedgerows cleared away to increase productivity the pollinators can starve.
See also the monographs on the Bumble Bee and Red-tailed Bumblbee
