Bees are insects of the Order Hymenoptera which feed on pollenand nectar. They constitute a group of about 20 000 speciesthroughout the world, known taxonomically as the SuperfamilyApoidea. Honeybees of the genusApis belong to the familyApidae, a sub-group of this superfamily. Although the question ofhow many honeybee species exist is still debated amongtaxonomists, at least four species are commonly recognized: thedwarf, or midget, beeApis florea, the giant, or rock, beeApis dorsata, the oriental (Indian, Chinese, Japanese,etc.) beeApis cerana, and the common (European, African,etc.) honeybeeApis mellifera.The existence of anothergiant tree,Apis laboriosa,has recently been confirmedfrom Nepal, but little is known about its biology.
All honeybee species areeusocialinsects, that is tosay that they engage in favourable social activity. A colony ofhoneybees consists of aqueen, several thousandworkers,and at certain seasons of the year - a few hundreddrones.Among the members of the colony there is division of labour andspecialization in the performance of biological functions.
The architectural design of thecombof all honeybeespecies is essentially similar: it consists of adjoininghexagonalcellsmade of wax secreted by the workers' waxglands. The bees use thesecellsto rear theirbroodandto store their food. The general utilization of comb space isalso similar among the species: honey is stored in the upper partof the comb, with, beneath it, rows of pollen-storage cells,worker-brood cells, and drone-brood cells, in that order. Thegroundnut-shaped queen cells are normally built at the lower edgeof the comb.
As an inheritedbehaviour characteristic, all honeybeecolonies tend to store a certain amount of honey and pollen astheir food reserve. The quantity of food stored depends uponseveral factors, including the seasonal availability offorage,the worker population of the colony and its rate of reproduction,the capacity of the nest, etc. Another important inheritedbehaviour characteristic lies in the colony's natural site ofcomb construction: whereas some Apis species build singlecombnests in the open, others build multiple-comb nests in darkcavities.
The distribution area ofA. floreais generallyconfined to warm climates. In the west, the species is present inthe warmer parts of Oman, Iran and Pakistan, through the Indiansub-continent and Sri Lanka. It is found as far east asIndonesia, but its primary distribution centre is southeast Asia.Rarely found at altitudes above 1500 m, the bee is absent northof the Himalayas. It is frequently found in tropical forests, inwoods and even in farming areas. In southeast Asia it is not rareto find a nest ofA. floreain a village.
As its name implies, the dwarf honeybee is the smallestspecies of honeybee, troth In the body size of its workers and inthe size of its nest. A nest ofA. floreaconsists of asingle comb, whose upper part expands to form a crest thatsurrounds the branch or other object from which the comb issuspended. Dwarf honeybees nest in the open, but not withoutcamouflage: most nests are hung from slender branches of trees orshrubs covered with relatively dense foliage, usually from 1 to 8metres above the ground. In Oman, whereA. floreanestsare frequently found in caves, such combs are without crests.
Combs of the dwarf honeybee are well covered with layers ofworkers clinging to each other' often three or four deep. Aboutthree quarters of the colony's worker population are employed informing this living protective curtain of bees. When disturbed,this curtain shows a "shimmering" movement, theindividual trees shaking their abdomens from side to side in asynchronous manner; at the same time, a hissing sound isreleased. If the colony is further disturbed, the worker treesraise their abdomens and take off from the curtain to attack theintruder.
The section of comb surrounding the support (in Fig. 1/1, asmall tree branch) consists of adjoining honey-storage cells thatform a crest, from whose inroad curved surface the trees take offand on which they land.The communication danceby scouts,announcing the discovery of a food source, also takes place onthis platform. Adjacent to the rows of honey-storage cells is thesection of comb which the workers use for storing pollen. Beneaththis band of pollen-storage cells is the area where the workerbrood is reared. Prior to the swarming season, drone-brood cellsare added, adjoining the lower rows of the worker-brood cells.When a colony loses its queen, emergency queen-cells are builtfrom normal cells containing young worker larvae.
To ward off ant attacks, the workers coat both ends of thenest support with sticky strips of propolis, or "plantgum", from 2.5 to 4 cm wide.A. florea is the onlyhoneybee that uses this defensive technique.
During the season when there is an ample supply of nectar andhoney, populous colonies of the dwarf honeybee send out multiplereproductive swarms. In addition, colonies of this tree have ahigh degree of mobility. Disturbance by natural enemies, exposureto inclement weather and scarcity of forage are among the majorcauses of colonies absconding.
In comparison with other honeybee species, the amount of honeythatA. florea workers will store in their nests is small,usually not exceeding several hundred grams per colony. In someparts of Asla, the rural people have devised a scheme forharvesting this honey. First, nests or the bees are transferredfrom their natural sites to the village, and then, using twineand two short twigs, the nest is clamped and attached to a smallbranch of a tree. The upper part of the comb, containing thehoney, is cut out, and the honey is squeezed out from it. Aperiod of about six to eight weeks is allowed for the bees torepair the comb and replenish it with honey, and then it isharvested again. This method is not always reliable, however,because most colonies will abscond either shortly after theirtransfer to the new site or after the first or second harvest hastaken place.
Where nests ofA. floreaare abundant, several ruralfamilies can subsist on the income generated from beehuntingalone. Although the practice appears ecologically destructive,particularly insofar as it reduces a valuable population ofnatural pollinators, it does not always destroy the colony beinghunted. Workers and laying queens of the dwarf honeybee are ableto respond to nest predation quickly. The entire colony,accompanied by a laying queen, can fly several meters away toregroup, and later abscond. Some absconding colonies are able tosurvive to build their new combs in a nearby area.
The distribution area of the giant honeybee is similar to thatof the dwarf honeybee: it occurs from Pakistan (and, perhaps,parts of southern Afghanistan) in the west, through the Indiansubcontinent and Sri Lanka to Indonesia and parts of thePhilippines in the east. Its north-south distribution ranges fromthe southern part of China to Indonesia; it is found neither inNew Guinea nor in Australia.
The giant honeybees of Nepal and the Himalayas have recentlybeen reclassified as belonging to another species of Apis,A.laboriosa. It is not yet c]ear whether the giant honeybees ofSikkim and Assam in northern India, western Yunan Province inChina, and northern Burma should he classified asA. dorsataor asA. laboriosa, but in the present state of ourknowledge, it is safe to consider that all the giant treesconstitute a single taxonomic identity. Although minor variationsin anatomical, physiological and behavioral characteristics existamong the different geographical races of the giant honeybees,they are essentially similar in all their major biologicalattributes.
The giant honeybees are found predominantly in or nearforests, although at times nests may be observed in towns nearforest areas. The bee shares the openair, single-comb nestinghabits ofApis florea, suspending its nest from the undersurface of its support, such as a tree limb or cliff. In general,A. dorsata tends to nest high in the air, usually from 3to 25 meters above the gound. In tropical forests in Thailand,many nests are suspended inDipterocarpus trees from 12 to25 meters high: this tree is probably preferred as a relativelysafe nesting site because its smooth bark and its trunk risingfor 4 to 5 meters before branching out make it very difficult ofaccess to terrestrial predators. Nonetheless, aboutthree-quarters of the worker population of a colony of gianthoneybees is engaged in colony defence, forming a protectivecurtain three to four trees thick in the same way asApisflorea. While birds are common predators ofA. dorsata,the workers' large body size protects them reasonably wellagainst ant invasion, so that the sticky bands of propolischaracterizing the nests of the dwarf honeybee are not foundsurrounding the nests ofA. dorsata, nor are the nestshidden by dense foliage. Nests ofA. dorsata may occursingly or in groups; it is not uncommon to find 10-20 nests in asingle tall tree, known locally as a "bee tree". InIndia and Thailand, tree trees harbouring more than 100 nests areoccasionally seen in or near the tropical forest.
The single-comb nest, which does not have the crest ofhoney-storage cells typical ofA. florea nests, may attimes be as much as one meter in width. The organization of thecomb is similar to that in the other honeybee species: honeystorage at the top, followed by pollen storage, worker brood anddrone brood. At the lower part of the nest is the colony's activearea, known as the "mouth", where workers take off andland, and where communication dances by scouts, announcing thediscovery of food sources, take place. This dance takes place onthe vertical surface of the comb, and during its progress, thebees must have a clear view of the sky to observe the exactlocation of the sun. Workers ofA. dorsata are howeverable to fly at night, when the light of the moon is adequate.
In many places, the arrival ofA. dorsata colonies isan annual event, occurring at the end of the rainy season or atthe beginning of the dry season, when several species ofnectaryielding plants are in bloom. This phenomenon leads tospeculation thatA. dorsata has a fixed pattern in itsannual migratory route. Most professional bee-hunters know whenand where the trees are to arrive, but they wait patiently untilthe end of the honey-flow period before taking down the nests.Observations in northern Thailand indicate that if the nests areleft undisturbed, the colonies will eventually abscond or migratewhen their food reserves have been depleted, usually at the endof the summer months. By the beginning of the rainy season,A.dorsata colonies are found deep in the lush jungles.
A. dorsata is well known for its viciousness when itsnest is disturbed: the mass of defending workers can pursueattackers over long distances, sometimes more than 100 meters.Notwithstanding its ferocity, however, this tree's honey ishighly prized locally, in some places commanding the best pricesin local markets,
Nests of the giant honeybee have been hunted by man sinceantiquity, and today, organized bee hunting exists in many partsof Asia. In Thailand, bee-hunters must pay fees for permits tohunt the bee in state forests, and landowners possessing beetrees sell annual or biennial rights to hunt nests from suchtrees.
Some professional bee-hunters prefer to work at night. Smokeis used to pacify the bees, which are then scraped from the comb.The nest is cut and placed in a cloth bag, which is lowered to anassistant on the ground. This method does not result in allcolonies being killed: about a fourth of the colonies in a beetree that has been worked over are able to reconstruct theirnests.
The recent intensification of bee hunting has caused an alarmin several Asian countries. There is general concern that thetotal number ofA. dorsata nests all over Asia may be onthe verge of declining, partly due to shrinking forest areas, theuse of toxic pesticides in foraging farm lands, and bee hunting.
For ages, colonies of the oriental honeybeeApis ceranahave provided mankind with honey and beeswax, as well asfurnishing invaluable service in the pollination of agriculturalcrops. This bee's range of distribution is far greater than thoseofA. florea andA. dorsata: it is found throughoutthe tropical, sub-tropical and temperate zones of Asia, occurringin the Indian sub-continent and Sri Lanka in the west, throughsoutheast Asia, to Indonesia and the Philippines in the east.Further north, it is found in the southern USSR and China,through the Korean peninsula, to Japan. This wide range has ledto important variations among the bee's geographical races:particularly between the tropical and temperate races, there arewide differences in workers' body size, nest size, colonypopulation and swarming and absconding behaviour, The temperateand sub-tropical races appear to store greater quantities of foodthan the tropical races, which in turn are more mobile than theformer, tending to swarm, abscond and migrate quite frequently.
In the wild, the oriental honeybees construct theirmultiple-comb nests in dark enclosures such as caves, rockcavities and hollow tree trunks. The normal nesting site is, ingeneral, close to the ground, not more than 4-5 meters high. Thebees' habit of nesting in the dark enables man to keep them inspecially constructed vessels, and for thousands of yearsApiscerana has been kept in various kinds of hives, i.e. claypots, logs, boxes, wall openings, etc. Despite the relativelyrecent introduction of movable-frame hives, colonies ofApiscerana kept in traditional hives are still a common sight inthe villages of most Asian countries. As a result, the feralnests of the oriental honeybee in tropical Asia sustain fewercasualities in being hunted by man than those of the dwarf andgiant honeybees.
The several combs of an A. cerana colony are built parallel toeach other, and a uniform distance known as the "beespace" is respected between them. The body size of theworkers of this tree is much smaller than that of theA.dorsata workers, and its brood comb consists of cells of twosizes: smaller for the worker brood and larger for the dronebrood. The queen cells are built on the lower edge of the comb.As in the other Apis species, honey is stored in the upper partof the combs, but also in the outer combs, adjacent to the hivewalls.
Following the invention of the movable-frame hive for theEuropean honeybee about a century ago, traditional beekeepingwith A. cerana has been partially replaced by this modern methodin several Asian countries, and at the same time attempts havebeen made - with varying degrees of success - to improve hivingtechniques and colony management.
There are many geographical races of the common honeybeeApismellifera, distributed widely throughout Europe, Africa, andparts of western Asia, as well as in the Americas. All theseraces display similarities in their basic biological attributes,e.g. the construction of multiple-comb nests in dark cavities,colony social organization and division of labour, etc,
In the wild, the natural nesting sites of A. mellifera aresimilar to those ofA. cerana: caves, rock cavities andhollow trees. The nests are composed of multiple combs, parallelto each other, with a relatively uniform bee space. The nestusually has a single entrance. The temperate races prefer nestcavities of about 45 Litres in volume and avoid those smallerthan 10, or larger than 100, litres. Colonies of the Europeanraces are composed of relatively large populations, usuallybetween 15 000 and 60 000.
Many feral nests ofA. mellifera in the northeasternforests of the United States have been reported to store 25 to 30kg of honey per colony, and even more, during the nectar-flowspring season, and properly managed, commercially operated,colonies yield much more.
Anthropomorphically speaking, this behaviour of the temperateraces is obviously an evolutionary advantage: without it, thecolony faces starvation during the cold winter months, when foodis not naturally available and the temperature is too low topermit flight activity. The shortage of natural forage and thecold temperatures prevailing from late autumn until early springappear to play an important role in exercising rigidnatural-selection pressures on the colonies. As a result, bothferal and hived colonies of temperate-zoneA. melliferaare less likely to abscond than the tropical races.
The past three centuries have seen the introduction of thecommon honeybee to all the habitable continents. Outside Asia,beekeeping withA. mellifera constitutes an integral partof modern agricultural systems, furnishing crop pollinationservices as well as honey and beeswax. Although this bee is oneof the most studied animals, many aspects of its biology beingfully known, efforts over the past few decades to introduceA.mellifera into Asia have encountered a number of problems,such as the inter-species transmission of bee pests and diseases.
But successes have been reported from several Asian countriesas regards the commercial viability and the likelihood of aprofitable economic return of beekeeping withA. mellifera.It appears that the adaptability of the bees, appropriatebeekeeping technology, better understanding of forage ecology andsocio-economic suitability are among the most important factorsunderlying the further development of beekeeping with the commonhoneybee in Asia.
Among the four commonly-recognized species of Apis, only A.cerana andA. mellifera are kept commercially by man.Behavioural limitations of the dwarf and giant honeybees,particularly their practice of open-air nesting, prevents theirbeing kept in man-made hives for reasonably long periods, whilehiving colonies in specially-constructed containers is essentialin that it enables the colonies to be manipulated.
In many parts of the world, including several countries inAsia, commercial beekeeping depends on moving the honeybeecolonies to places where forage is abundant at certain periods ofthe year. Such migratory beekeeping often calls for the coloniesto be moved several times a year, over distances which may rangefrom a few kilometres to several hundred kilometres from the homebase. This approach is practicable only when the colonies are inmovable-frame hives, which can he transported without danger tothe hives or the colonies. From the practical standpoint,therefore, beekeeping can he A dependable agricultural occupationonly when the beekeeper can determine and control the number ofhives he owns.
Generally speaking, there are two possible approaches to thedevelopment of commercial beekeeping in Asia: the introduction ofmodern beekeeping withA. mellifera or the improvement ofexisting techniques for using A. cerana. Notwithstanding thedifficulties involved in establishing new apiaries of theintroduced colonies and in developing colony managementtechniques suitable to local conditions,A. melliferacolonies are generally more productive than those of A. ceranawhere forage is abundant, and the development of beekeeping withA.mellifera in Japan, the Republic of Korea, China and northernThailand is based on this finding.
On the other hand, where forage is available only marginally,colonies of A. cerana survive better and can produce with lowermanagement inputs than colonies ofA. mellifera. It is theabsconding behaviour of most, if not all, tropical races of A.cerana that creates a major obstacle to the development ofbeekeeping with this bee in rural areas in southern Asia. Sincethis behaviour is apparently triggered, at least to some extent,by an unfavourable hive environment, proper colony management maybe able to provide at least a partial solution to this problem.
Thus, only through systematic research and developmentactivities carried out locally is it possible to judge which ofthe two approaches to apicultural development should be adoptedto suit the socio-economic situation, the vegetation pattern andthe climatic conditions of each locality.