Swarming

The process of swarming represents the natural method of colony reproduction. Under certain conditions, often associated with the seasonal growth cycle of the colony, workers begin to raise additional queens in the colony. At some point before the virgin queens emerge from their cells, the old queen will depart from the nest with approximately half of the workers and drones and attempt to establish a colony at a new home site. The propensity for swarming and the conditions leading up to this behavior vary within and among races of honey bees. Sometimes one or more of the newly emerged virgin queens will also depart with a group of workers and drones in an "after swarm," also attempting to establish a new colony.

DISEASES AND PESTS Larval Diseases

Like all living animals, the honey bee is subject to the ravages of diseases and pests. The diseases range from viral to fungal in origin. One troublesome brood disease is called

American foulbrood disease. This disease brought about the establishment of many state bee inspection programs (6). American foulbrood disease is caused by Paenibacillus larvae larvae (formerly Bacillus larvae). Only the spore stage of this bacterium is infective and only in honey bee larvae less than three days of age. Another important brood disease is European foulbrood disease, caused by Melissococcus pluton. In both cases, beekeepers sometimes use an antibiotic (oxytetracycline) for disease prevention and treatment. Another bacterial disease of minor importance is powdery scale disease, which is caused by Paenibacillus larvae pulvifaciens.

All the known fungal diseases that affect the brood are of minor significance except for chalkbrood disease, which is caused by Ascosphaera apis. Until 1968, no chalkbrood disease had been found in the United States. Currently, chalkbrood is reported present in most of the states, and many beekeepers report reductions in their honey crop due to this disease. There is no effective chemical control for chalkbrood.

A number of viruses affect honey bees. Most virus diseases of bees are considered of minor importance and no treatment is necessary. Two brood diseases of viral origin are sacbrood and filamentous virus disease (formerly believed to be of rickettsial origin).

Adult Diseases

Nosema disease is caused by the microsporidian Nosema apis. This protozoan shortens the life span of adult bees and reduces their production of royal jelly. Consequently, brood and honey production are reduced by 30 to 40%. The subtle effects of this disease are difficult to recognize and most beekeepers do not realize that their honey bees are infected. Fumagillin is used by some beekeepers to treat this disease.

Chronic bee paralysis is a virus-induced disease that is occasionally seen in honey bee colonies. This disease mimics the effects of pesticide kills, and many beekeepers may misdiagnose the condition. Fortunately, the disease is not serious. It is generally believed that requeening can abate the disease.

Other minor diseases affect the health of honey bees but are of little economic significance. Noninfectious conditions caused by pesticides and poisonous plants, such as California buckeye (Aesculus californica), cornlily (Veratrum califonicum), death camas (Zygadenus venenosus), and some locoweeds (.Astragalus spp) can be serious problems in some years. A more detailed discussion of this subject has been published (7).

Parasitic Mites

The first of two problematic, then "exotic," parasitic mites of honey bees was detected in the United States in 1984 (8,9). Acarapis woodi, the tracheal mite, lives and reproduces in the thoracic tracheae (breathing tubes) of adult honey bees. During warmer times of the year, mites remain in young worker hosts only during the three weeks that they perform chores in the hive. When the workers begin to forage, the mites leave their original hosts at night, when the bees are relatively motionless, and seek newly emerged bees to infest. All castes of bees are susceptible, and the mites tend to remain in drones and queens. Tracheal mites feed by pushing their mouthparts through membranous areas of the tracheal tubes and sucking he-molymph (bee blood). Mite feeding causes hemolymph chemistry changes, destruction of flight muscles, darkening (healing?) of tracheal tubes, transmission of diseases, and reduced life expectancy. Colony losses are common in areas of colder climates, where new bees are not reared for months during the winter.

Menthol fumigation inside the beehive currently is the only registered and legal means of reducing the mite population. Treatments are temperature sensitive, with high heat driving bees from the boxes resulting in some queen losses. Once mite populations are reduced, they often can be prohibited from increasing by placing thin patties, made of two parts sugar to one part vegetable shortening, in contact with the bees in the hive.

The second important mite to be detected in the United States was the varroa mite, Varroa jacobsoni, found in 1987 (10,11). Varroa is an ectoparasite that feeds through membranous portions of the exoskeleton of adult and larval bees. Reproduction takes place only in capped cells containing worker or drone pupae. All developmental stages of the mite feed on the pupa. Physiologically immature male offspring mate with their sisters, delivering sperm that complete maturation in their sisters. When the bee emerges from its cell, the mites are liberated.

As with tracheal mites, Varroa feeding reduces protein content in the host's hemolymph and reduces its life span. As mite populations increase, two or more Varroa infest the same cell. The host pupa is apt to shrink and have malformed wings and legs. Such individuals are carried out of their cells by worker bees and discarded outside the hive. Without replacement workers, the colony perishes. Varroa also are disease vectors. In 1995 and 1996 there were so many Varroa in the country that we lost nearly 90% of our feral (unmanaged) colonies. Gardeners and commercial growers realized these losses when they noticed a total lack of honey bees on crops requiring pollination.

Introduction of plastic strips containing a time-release acaricide is the only currently registered, legal chemical control for Varroa mites. The selective acaricide kills the mites on contact without killing the bees. In a number of locations around the world, scientists are searching for new and different chemistries to control the mite. Other researchers are screening U.S. and foreign bee stocks for populations demonstrating tolerance or resistance to Varroa and the tracheal mite. Results look much better for the tracheal mite than for Varroa, which is an interspecific transplant from its original bee host, A. cerana (12).

How To Become A Bee Keeping Pro

How To Become A Bee Keeping Pro

Companies that have beekeeping stuff deal with all the equipment that is required for this business, like attire for bee keeping which is essential from head to torso, full body suits and just head gear. Along with this equipment they also sell journals and books on beekeeping to help people to understand this field better. Some of the better known beekeeping companies have been in the business for more than a hundred years.

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